Austin Healey 100 #174 Heatshields

The drivers footwell heatshields on  #174 were original and somewhat different from those that I have seen on later cars.  These heat shields are installed on all “Big” Healeys to limit the amount of heat that is radiated onto the driver’s footwell from the exhaust manifold and down pipe.

The Original Heatshield on the Front of the Footwell

Footwell Heatshield Around Pedal Apertures

Footwell Side Heatshield

These heatshields are all made of the same asbestos material, with a pressed pattern on one side, that was used throughout later Healey production. Later 100s used a different material which is called “millboard”. Millboard is softer, a little more flexible and of layered construction. All 6 cylinder Healeys used the same material as was used on #174.

As is the case on Healeys that I have seen the material was not fitted with the pattern consistently inward, against the footwell, or outward.  In fact on #174 of the two panels fitted around the pedals one was “pattern in” and the other was “pattern out”.

The heatshields on later cars were much more carefully shaped so as to  cover the exposed areas of the footwell more completely.

Also of note, and peculiar to 100’s I believe, is the fact that no spacers were fitted between the material and the footwell to produce an air gap as was the case in the later cars.

#174, being a very early car, has some interesting differences in the types of fasteners used throughout the car. This was the period when many BSF threaded fasteners were still in use and quite a number of slot head screws.

Heatshield Fasteners

As can be seen in the photographs taken before the heatshields were removed the fasteners were all installed with the nuts outward so the slotted “pan” heads of the screws were all under the carpet in the footwell.

Also of particular interest is the way that the panel around the clutch pedal and around the dip “dimmer” switch has been broken away, probably during assembly at Longbridge,  to provide adequate clearance.

I intend to reinstall these heatshields after painting them all over with latex paint to prevent their “shedding” asbestos fibers.

Posted in Healey Concours Information, Restoration Techniques, The Restoration of Healey #174 | 3 Comments

Brake Pipe Flare TSB

Technical Bulletin About Brake Flares

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Austin Healey BJ8 Water Pump Rebuild

Because the only available reproduction pumps are such c**p I have been selling a bunch of Austin Healey 3000 MkIII water pump rebuild kits and many people have asked me how difficult is it to rebuild one of these pumps?

The kits cost $US68.65 which includes domestic or international shipping.

The following is a step by step procedure for this job. It really isn’t that difficult.


The Later Style BJ8 Pump

The identifying feature for the BJ8 style pump is the lack of a hex nut in the center of the pulley because they use a “press on” pulley. A puller is  required to remove these pulleys.


I Have Used This “Home Made” Puller For Years

The puller uses a 7/16 UNF forcing screw and the mounting bolts are on a 1.375″  pitch circle diameter. It is installed to the pulley using four 5/16″  x 1 ” UNF bolts.

Once the pulley has been removed the bearing locking wire needs to be located and removed.

Using a suitable tool remove the locking wire. The wire is usually made of brass or copper.

A Spike Tool Can Be Used To Remove The Wire

If the wire cannot be located and removed this step may be skipped although the force required to press the bearing out will be much higher and  there is a significant risk that the pump body will be damaged.

Once the wire is out the bearing and impeller can be pressed out of the body.

Be Careful to Provide Clearance For The Impeller

While pressing out the bearing and impeller assembly be careful to provide clearance for the impeller and DON’T let it drop to the floor!!

The Bearing, Seal and Impeller are Removed as an Assembly

Once this assembly has been pressed from the body the impeller must be pressed off to replace the bearing and seal. The impeller casting is easily broken so care must be taken when pressing it off the bearing shaft.


Use a Small Bearing Spreader Installed Below the Seal Face

Carefully press the bearing shaft out of the impeller.

The Impeller Must Be Supported On the Seal Face

Once the impeller has been removed the bearing and seal can be discarded.

Dis-assembly Completed

Careful examination of the seal from this recently rebuilt pump reveals that is is badly cracked.

I Suspect That This Seal Was Cracked During Pump Assembly



After cleaning and inspecting all the parts reassembly begins by inserting the seal back into the pump BY HAND!!

Be Sure to Clean The Seal Seating Position

I always spread a very small amount of silicone sealant on the area of the seal that seats in the pump body.

I use a large socket to press the seal BY HAND securely into its seat in the pump body.

The Seal Must Be Well Seated and Straight

Next the bearing is pressed into the pump body from the outer end of the body. The shorter end of the bearing shaft accommodates the pulley.

NEW NOTE: When talking with a company that rebuilds lots of heavy equipment water pumps they recommended using a a few drops of Loctite (or similar) bearing retainer at this stage just to ensure that the bearing stays put in the housing. They have found that age and normal manufacturing tolerances can result in the fit being a little loose.

Bearing orientation Press the bearing in using a tool which prevents load being applied to the bearing shaft.

Avoid Pressing on The Bearing Shaft

Press the bearing in until the groove in the bearing is aligned with the internal  groove inthe pump body. Don’t go too far.

Stop Pressing When The Grooves Are Aligned

Now install the wire retaining clip into the grooves. This can be a pain to achieve as some of the bearing grooves are smaller or larger than the originals. For replacement wire try 12, 14 or 16 gauge household copper wire.

Use Pliers to Push The Retaining Wire Into The Grooves

Check the sealing face of the impeller for excessive grooves.

Deep Grooves in The Impeller Seal Face Should be Removed

If the grooves are not too deep you can face the impeller off by rubbing it on sand paper on a flat surface.

Glass Makes a Great Flat Surface

If the grooves are really deep you can can face the impeller off in your lathe…you do have a lathe don’t you? Use fine sandpaper to produce a smooth surface.

There is Nothing Like a Lathe For This Job

Once the seal face is prepared the impeller can be pressed into position. Note that the shaft is on the base of the press which prevents the bearing from taking the pressing load.

NEW NOTE: I have occasionally encountered problems with leakage between the bearing shaft and the impeller. Using Loctite (or similar) here prevents this from becoming an issue.

Pressing impeller 2

Sockets Make The Best of Press Tools

When the end of the shaft is level with the face of the impeller STOP..  The impeller to body gap should be something like this.

Stop When The Impeller Gap is About This Big

If you rotate the pump at this stage your should hear the distinct “hissing” sound of the carbon seal.

Now press the pump down into the pulley.

Press The Pump Down Into The Pulley

Again STOP when the end of the shaft is level with the end of the hole in the pulley.

This Pulley is Pressed on to The Correct Position



BTW I have rebuild kits for all 6 cylinder Austin Healeys

$US68.65ea which includes intentional shipping.


Posted in New British Sports Car Parts, Restoration Techniques | 15 Comments

Austin Healey Steering Lever Removal

One of the difficult jobs when repairing or restoring the steering box or steering idler on an Austin Healey 100 – MkIII is the removal of the steering levers. These levers are fitted on to a tapered spline and without the correct tool can be very hard to release without damaging the steering box, steering box lid or shaft.

The Steering Lever Can Be Very Difficult To Remove

Using this simple step by step process should prepare you for rebuilding the steering box or steering idler without damage.

First remove the cotter (split) pin. Sometimes you need to turn the nut a little to allow the pin to be removed.

Remove The Cotter Pin

The BN1/2 nut is 1″ AF, as I recall the 6 cylinder cars use a larger nut. This can be very tight but it is usually not seized, just tight.

Loosen The Nut

Next remove the nut and the large washer that is under the nut.

Once the washer is removed reinstall the nut and turn it down until the top of the shaft is level with the bottom of the castellation slots in the nut.

Castellation Cuts Level With The Top Of The Shaft

This is the secret weapon!

These Pitman Arm Pullers are readily available at Harbor Freight,  Princess Auto and similar discount tool suppliers or on eBay for about $20.

With A Small Modification This Is THE Tool For The Job

The trick is to use a disc grinder to slightly enlarge and “round” the gap between the jaws so that the puller fits under the puller lugs on the steering lever.

The “Secret” Modification

Again … The 6 cylinder component is slightly larger and will require a little more grinding on the jaws of the puller. Remove just enough material to permit the puller to fit on snugly.

Put a little grease on the threads of the forcing screw as these tools are usually shipped “dry”.

The Modified Puller Ready For Use

Tightening the forcing screw will exert the necessary pressure to release the steering lever.  I take it in small increments and check that the castellated nut still turns freely on the shaft between tightenings.

I have had cases where the lever was forced so tightly on the taper that the end of the shaft started to crush down on the split pin holes before the lever pulled off.  If you find that the castellated nut is starting to bind on the threads before the lever is released this could be happening. Try pressing a short piece of tightly fitting steel rod through the split pin hole and start over again. The piece of rod will prevent the end of the shaft from collapsing down on the split pin hole although you may have to use a pin punch to remove the piece of rod once you are done and possibly have to dress up the threads a little.



Posted in Restoration Techniques | 20 Comments

Healey #174..Original Dash Paint…A Real Mindbender

In my continuing efforts to accurately archive as many details of this very early Austin Healey 100  as I can I have spent time gently sanding through the paint on the dash in an attempt to determine its original colour.

I want to emphasize that all I am doing here is cataloging what I’m finding as I disassemble this particular car and I am in no way suggesting that  this information will be accurate for other Austin Healey 100s of this era.

The dash consists of 2 aluminium pressings. One I call the Dash and the other, which is attached to the Dash I call the Instrument Pod.

The Dash

The Instrument Pod

The Instrument Pod is mounted onto the surface of the Dash and attached using screws inserted from the rear.

Here are some background points:

1. The back of the Dash is a dark brown with some small areas at  the ends having been over sprayed with black (The reverse of the front of  the Dash oddly. More about that here ).

2. The Dash has been apart. i.e. the Instrument Pod has at some time  been separated from the Dash and the rubber strip which is meant to act as a seal between them is missing. (I’m  absolutely confident that the safety gauge has never been removed from the  car and pretty sure that the  Dash itself has never been removed from the car. Because the safety gauge has a liquid filled capillary tube running from it to the radiator the Instrument Pod almost certainly has never been moved more than a few inches from its installed position).

3. As every part of the front of the Dash has  black primer which  has been sprayed over with a brown paint (primer?) which is consistent with the rest of the paint on the inner body,  I think it is fairly safe to conclude that the Dash has never been stripped to bare metal. (The outer surfaces of the body have been stripped bare and on them light grey primer has  been used).

4. The last paint applied to the Dash was a silver/blue colour which was very poorly done in that there is no paint up over the top of the Dash where it is hidden from view by the rear lip of the front shroud.

The Dash appears to have been painted red originally as can be determined by studying the image below of an area adjacent to the grab handle on the right side of the Dash

Close up of of the paint layers on the Dash.

The next image is from the area of the Dash at the top of  where the Instrument Pod is installed.

Paint layers at the Dash to Instrument Pod transition area.

Of particular note is the gloss black which was the top surface of the  Dash under the Instrument Pod.

When Peter Svilans and I first looked at that black we thought it may be a dark blue, but we have concluded that it is definitely black.

There is no sign of red  under the part of the Dash originally covered by the Instrument Pod or anywhere on the Instrument Pod itself.

Paint layers on the Instrument Pod

The grey on the instrument pod  (1st coat on top of the medium brown primer) is very similar, if not identical to the blue/grey (Healey Grey?) that I have concluded was the original colour of this car.

Although most of the original interior was missing from the car some remnants remained and they appear to confirm that the interior was trimmed in dark blue.

This one really has me scratching my head as the conclusions that I have come to are completely out of line with what is “accepted” as the usual.

Anyone who hasn’t fallen asleep so far and would care to comment your thoughts are very welcome. Please comment using the button at the top of this post.

I’m particularly interested if anyone can suggest a sequence of painting events which may have created this combination of colour coats.

Posted in Healey Concours Information, The Restoration of Healey #174 | 7 Comments

Austin Healey #174…What colour was the frame?

One of the things I tried to take particular care to record as I took this car apart was any evidence of original paint.

There has been much discussion about what colour the frame and inner body of these early cars was originally.  Many owners have reported finding that the frame and inner body, and for that matter the insides of the outer panels, were painted a “chocolate brown”.

There is no question about that on this car.   It was black!!

I am aware that the colours do not display well in all of these photos but ‘m pretty sure you will get the idea.


This is what the inside of the rear shroud looked like. Black!!

This is what was under the asbestos heatshields. Black!!

I have discussed this subject with one expert and I believe he has an good  explanation. “The factory, probably Jensens,  painted everything with a cheap black paint that probably faded to a dark brown colour over the years. ”

I  found that chocolate brown paint on parts which could be described as “sub-panels”, namely the dash and the gravel guard.

This is the inside of the dash. Chocolate Brown!!   (some repair required here)


But, here is the interesting part.

This is of the corner of the inside of the dash…Black over Chocolate Brown!!

 This definitely poses a bit of a problem for the “faded to dark brown” theory!!!!

P.S.  I would like to make the intent of these posts absolutely clear.

All I’m doing here is trying to document and publish my findings on THIS PARTICULAR CAR which I want to restore to as close to original delivery condition as possible.  In no way is this intended to upset the concours “applecart”.

I am not trying to imply that any or all other early Austin Healeys should have the same characteristics…This is what I found on #174 and that is all.

I have disassembled a lot of Healeys, starting way back in 1976, and I’m pretty experienced at determining what is original and what has been monkeyed with.

To prevent any confusion if I’m not sure that the characteristic I’m describing was on this car when delivered I won’t post it here.

Michael S

Posted in Healey Concours Information, The Restoration of Healey #174 | 1 Comment

Austin Healey #174….Unusual Front Fenders

Now that I have had the body panels for this car chemically cleaned I am able to see some details on the front fenders which are rather unusual and not evident on later versions.


First is the strange way that the vent holes have been manufactured (that’s if you do actually  “manufacture” a hole).

This is how they looked before cleaning.

The first thing that is odd are the little cuts at either end of the vent hole. This is what one looks like close up from the inside.

My first thought was that there had been cracks at the ends of the cutouts and someone had run a small saw down the crack and “stop drilled”  it but that just does not make sense.

  1. I have never seen cracks appear at the cutouts on a BN1 or BN2 fender and considering that this is a low mileage car that’s pretty unlikely.
  2. The cuts are almost the same on both fenders and only one, the rear one in both cases is “stop drilled”.
  3. On one of the cuts, unfortunately the photo is not good enough to show, the cut runs for about 1/2″ then does an abrupt 30 degree turn before continuing another 1/2″. Try doing that with a hacksaw!!
  4. As can be seen in the detail picture the cut edge of the cuts, and for that matter the entire cutout, is quite rough with shards remaining in many spots.

It is almost as though the holes were cut out using a primitive water jet system….but in 1953!!! And, if they were using some sort of cutting tool,  it looks as though they started at a drilled hole and then moved in to the area to be cut….why not start inside the line?

Anyone got any idea of the tooling or technique used to make these cutouts?


The other oddity is the construction of the fenders themselves.  Each has been made from 3 separate pressings.

There is a weld running vertically at the top of the wheel well.

and another, also running radially near the bottom of the headlight.

These welds are some of the finest production ‘”butt hammer welds I have ever seen!!

I surmise that the manufacturers were still developing their manufacturing techniques and, although rather labour intensive, this is one system that they considered using.

Anyone else come across BN1 fenders made this way?

Added 3 July 2012

Since the original posting of this article we have had the opportunity to study these fenders in more detail and found yet another interesting feature.

Unlike all other Healey fenders that I have ever seen the very bottom of the fender where the metal is bent in to meet up with the inner sill these fenders have a separate piece of metal. This metal is attached with a spot welded lap joint…a real rust trap!!

The Lap is About 1/2″


Although the bottom of the right front fender was rusted and and badly repaired the original lap joint was still evident.

The photo below shows a detail of the rear of the lap joint as viewed from the inside.

The Round Hole Appears to be a Later Addition But the Elliptical Looks to be Original

The next interesting item is a part of a photograph that I received of Healey 100 #384.

The Vent Cutouts in Car #384

You have to look closely but it has the same odd cuts that #174 has at the ends of the vent cutouts!!

And, while we are on the subject of fenders, this photo is of the dog leg area of the right rear fender from #174.

The Cardboard is an Accurate Rear Dogleg Template

The left fender’s dog leg area is exactly the same shape as the template.. The right must have been a Friday Fender.


Posted in Healey Concours Information, The Restoration of Healey #174 | 5 Comments

Austin Healey #174 Healey Grey??….Paint History

When I received the Heritage Certificate for this car I was surprised to note that the original colour was noted as “Healey Grey”.  I have not been a close follower of all the work that people have done on these very interesting “early” cars so was not aware of the discussion that had gone on among those “in the know ” about this colour.

When I broached the subject with one expert whose opinions I respect greatly, he was pretty sure that the reason that the name “Healey Grey” has been listed on Heritage Certificates is the source of information for those certificates. He gave the following as the reasoning:

1. I have record in the Hundred Registry of quite a few early cars logged as being painted in “Healey Grey”, and others in “ Healey Blue”. They seem to have used the two terms back and forth to mean the same thing, though some we know had no metallic content, while others had.

2. The naming of the paint on the build cards as Healey Blue or Healey Grey goes well into November of ’53 (with Body numbers into the 700’s) with a few of them specifying non metallic while most do not make the determination. So it definitely wasn’t a case of sequential evolution of the paint, but seemed to be randomly making use of metallic or non metallic and not stating the difference on the build cards.

I think that reasoning is very sound and was prepared to accept that this car was painted Healey Blue aka “Ice Blue Metallic” until I started looking a little more closely.  I carefully sanded through the paint layers on the rear shut face of one of the doors and this is what I found.

I believe I was very lucky that no one had taken the time to strip this area of the car down to bare metal  and that what was revealed is indeed a true history of the paint jobs over the last 59 years.

Here is what I think happened with this car:

The panels, like the chassis from John Thompson Motor Pressings, were painted in black chassis paint probably by Dowty Bolton Paul before shipping to Jensens.  (On this car the frame colour is definitely black not “chocolate brown” as others have described theirs. Chocolate brown however is indeed evident on the back of the dash and under the gravel guard).

Jensens did the assembly and once that was finished they blew in the areas where the black had been damaged with red oxide primer before applying the finish colour to all the outer surfaces, the door shuts and presumably the inside of the boot and bonnet.

My bet is that this car was sent to a dealer and didn’t sell, possibly because it looked a bit dowdy next to the Healey Blue ones,  so the dealer gave it a quick Healey Blue paint job to move it off the lot. That is just conjecture on my part but having worked in dealerships in the ’60s I know that in New Zealand they weren’t above painting a new car completely when the customer wanted one in a different colour!!
Some time later someone decided that they wanted the car in white so it got a total exterior grey primer then white paint job, over what was there,  including blowing in the wheel wells over the previously unpainted black frame paint. The white extends right up the door face so it is unlikely it was a “add white coves” job.
Next someone decided to do a Healey Blue with red interior so they stripped the outer surfaces completely down to bare steel applied a grey primer then a coat of Healey Blue which is why Ice Blue Metallic over grey primer is all I was able to find on those surfaces.

I took the door to a guy in the paint business I have known  for years  and he picked it right away!! He said it is the same as an old  Ford colour Spinnaker Blue. He mixed some up and it is absolutely identical to that non metallic blue/grey so, unless someone can convince me that this car was not that colour originally,  that is the colour it will be when I finish it.

Any comments would be more than welcome.


The question of whether or not “Healey Grey” was a official colour for the early 100s has been discussed at length since I first posted this article. After several phone calls and emails on the subject Roger Moment was good enough to send me following which, although somewhat bizarre, sounds  as though it may be a reasonable explanation for the confusion on the subject:

“I have build sheet data for many early 100s.  much of it came form John Wheatley who copied the records when he worked at Longbridge in the 1950s.  Some I researched at Gaydon years ago.  Of some 300+ entries covering bodies up to B. 400, six list “Blue”, 47 are colors other than blue, primer, or no color is shown (my data source didn’t list the color), and the remaining 247 ALL list Healey Grey!!!! Besides, I know of B. 691 that has the color listed as Healey Ice Blue and this is a non-metallic blue paint. so, B. 133 is listed as Healey Grey and it IS a metallic blue.
The BMC Service Paint Scheme pamphlet shows for the Austin-Healey 100 (BN1, BN2) Ice Blue (Straight), Code BUL.18 (See BN.2 Ice Blue Metalli-chrome)
    and for the Austin-Healey 100 (BN1, BN2); 100-Six (BN4, BN6), 3000, and 3000 Convertible (BJ7) Ice Blue (Metalli-chrome), Code BU.2 (See BU.18 Ice Blue (Straight).
There is NO mention of “Healey Grey”, nor for the various colors (grouped as Greens, Blues, Reds, etc.) under Greys there is no ?Healey Grey.
I believe that “Healey Grey” was a term that was used on the assembly line when filling out the cards, but there is NO ICI color code for it. It only shows up for blue cars among the first 400 or so Healey 100s, and never shows up again after that (and admittedly my records are incomplete).  B. 691, which is done in non-metallic Blue, is probably but one of some number of such cars.
We also know that there were LOTS of metallic Blue Healeys in the first few hundred.  I have a B&W photo taken by BMC of the Healey 100 production line on Sept 28th, 1953.  During this week cars with body numbers in the 300s were being built, and you can see from the appearance of the paint in the photo that ALL of the cars in the two assembly lines have metallic paint.Therefore, I cannot agree that “Healey Grey” is either a special color OR the non-metallic blue used on Healey 100s.”


So although this does not really do much to explain the unusual original colour on #174 it sheds some light on why the colour is denoted as “Healey Grey” on the Heritage Certificate.

Posted in Healey Concours Information, The Restoration of Healey #174 | 11 Comments

The Story and Disassembly of Austin Healey 100 Number 174

This very early Austin Healey 100 has the serial number is 142618 making it the 150th production car (the first production car as body #24) and it left Longbridge on 25 August 1953.

I know almost nothing about the history of the car other than it was sold on eBay to the person from whom Blair Harber purchased it in 2006.

Based upon the type of rust damage it would seem that the car has not spent any road time in the Northeast.

Upon close examination it turned out to be a very solid car for one that is almost 60 years old!!

Unfortunately the main floors and trunk floors are rusted through, probably as a result of water being trapped in the carpets and under the fuel tank and the seats and  most of the trim, many of the electrical components, the boot lid and the gearbox and overdrive are missing.

The odometer indicates 15636 miles so I figured it has probably done 115K miles or maybe even 215K miles but, as I disassembled the car, it became quite evident that it had probably not done 100K miles as for one thing,  the pedal rubbers had a relatively small amount of wear.

Some other things that I came across that have me doubting that the car has done 100K miles are:

  1. Very little wear on the shackle pins for the rear springs
  2. No play in the king pins and no indication that they had ever been rebushed.
  3. All original tie rod and side rod ball joints none of which exhibit any wear or signs of ever having been adjusted.
  4. All the original bolts mounting the original front shocks and very little indentation under the mounting bolts on the shock bodies.
  5. All the original washers and special nuts on the front anti roll bar and for that matter all of the rest of the parts I removed.
  6. No play at all on the clutch or brake pedal pivot shaft.
  7. Virtually no body damage and certainly no signs of collision damage that had been repaired.
  8. Very little wear on the door latch slides or the door hinges.
  9. Differential backlash within original specifications.
  10. Very little wear on the wire wheel splines.
  11. All the original bolts in the engine mounts indicating that it had probably never been removed.

I will know more when I start stripping the engine as that is the real indicator.

Some of the things that make me suspicious that the car has done more than 15636 miles are:

  1. The angle adapter for the speedo cable has a  broken cable section in it so the odometer has not been working for at least some time.
  2. The battery cables had all been replaced with huge gauge cables and the battery had apparently be relocated to the trunk.
  3. The heater had been taken out and re-mounted on an aluminum plate. I can only imagine that this was done because someone could not access the lower heater mounting nut with the engine in place.
  4. The car appears to have been painted 3 times over the original paint. (More on that later)
  5. A cracked right rear shock ear that had been repaired using a reinforcing plate.
  6. One rear spring has been replaced.
  7. Some natty stainless steel washers under the 4 screws attaching the shroud to the frame at the front of the hood opening.

The dis-assembly of the car is now complete and the body shell is back from Techno-Strip ready for the reconstruction to begin.

During the diss-assembly I encountered a number of interesting “features” which I intend to highlight in upcoming posts.

Among these are:

  • An interesting history of the paint on the car dating back to its original colour.
  • A wonderful record of what I believe are the original fasteners used to assemble this particular car.
  • Front fenders which are different in several ways to any I have come across before.



Posted in Healey Concours Information, The Restoration of Healey #174 | 2 Comments

Austin Healey Roadster Windshield Post Repair

The windshield frame on the pre-1963 6 cylinder Healeys is secured to the windshield posts with four 10/24 chromed Phillips head steel screws. The 100 posts used 10/32 threads.

The Red Part is the Post

If the windshield has been fitted to a car that has been winter driven in areas where road salt is used it is very unlikely that you will be able to remove the screws without at least some of them breaking off. I have never had much luck removing steel threaded fasteners from aluminium when corrosion of this type has occurred. It seems that the aluminum forms aluminium oxide which swells into the space between the steel and the aluminum and jams the fastener completely. Heating usually works when you have a steel in steel situation but it is seldom successful when aluminium is involved. Try as you may the end result is usually something like this:

A Typical Broken Off Screw

This presents a serious problem. These screws are right in front of your eyes when seated in the car and any type of repair which alters their installed appearance becomes very obvious.

One option is to drill and tap a new hole either just above or just below the broken off screw and then drill a new mounting hole in the windshield frame to suit, easy, practical but UGLY!!

For many years we seemed to have enough spare windshield posts from which we had managed to remove all the screws to just fit a replacement, unfortunately, those days are long gone and now we have to resort to a repair.

I have tried to very carefully drill out the steel screw with progressively larger drills until, hopefully, the root diameter of the screw is reached, with the drill right on center, and the thread can be pulled out like a spring. This just doesn’t work. Even if you manage to get to the correct diameter on center when you try to pull out the remaining thread it is very brittle and will not come out. Usually you don’t even get to that point before breaking off a drill bit inside the screw as the drill breaks through the bottom of it.

After many attempts I finally came up with what has proved to be a satisfactory if somewhat labour intensive method of saving the day!! this takes patience and a steady hand but, with windshield posts becoming harder and harder to find, it is worth the trouble.

You start by drilling small (1/16″ dia) holes around the entire perimeter of the broken off screw to a depth of about 5/8 “. Try to avoid drilling right through and definitely avoid breaking off drill bits as you do this.

You Can Get Aboult 8 Small Holes Around the Broken Off Screw

Once they are all drilled use a slightly larger bit to increase the size of the holes until they start to run into each other. Again proceed carefully and be careful not to break off any drill bits.

Enlarged Holes Will Start to Run Into Each Other

Once this stage has been reached use a small pin punch to tap the broken off screw sideways back and forth until it becomes loose in the hole and can be lifted out with needle nose pliers.

A Little Patience and The Broken Screw Can Be Removed

Once this is done you need to find a flanged 10/18 Rivnut. These are usually used to install a threaded nut into sheet metal and are available at most good hardware stores. To be absolutely correct for the 100’s 10/32 Rivnuts will be required which are harder to find.

A Flanged 10/18 Rivnut. (This one as a 10/18 screw in it.)

The outside diameter of the flange on these is usually about 7/16″. This is too big for our purposes so I usually mount one in my drill press on a piece of threaded bolt and with the drill press running run a file on the edge of the flange to decrease its diameter to almost nothing resulting in a flange of just under 5/16″ outside diameter. At this stage I often roughen up the outside of the Rivnut barrel to assist with adhesion of J B Weld used in the next stage.

Rivnut Drill Ready for Filing Down

Once I’m happy with this I drill out the ragged hole in the windshield post to  5/16″  diameter.

Done correctly this will leave just a thin wall of post on either side of the hole.  Next slide the Rivnut, flange first, into the hole.

The Flange Has to be Small Enough To Fit Into The 5/16″ Hole

The hole has to be deep enough to entirely accommodate the modified Rivenut.

When The Hole is Deep Enough The Top of The Rivnut Will be Flush With The Post Surface

The next part is easy.  Remove the Rivnut and mix up a small batch of J B Weld and put a little into the hole taking care to ensure that it coats the sides and the bottom.

Smear a little grease on a  long 10/18 screw and thread it into the modified Rivnut, be careful to ensure that no grease remains on the outside surfaces of the Rivnut  (The ones your roughened up).

Smear J B Weld on the outside and bottom of the Rivnut and push it into the hole then, using a small screwdriver as a spachelor, squeeze as much J B Weld into the hole around the Rivnut as you can get in.

As a precaution, to ensure correct positioning, you can install the side section of the windshield frame at this stage but make sure you put a smear of grease on the surface where it will contact the J B Weld.

A few hours later, after the J B Weld has hardened, you can use a file to remove any excess adhesive. The J B Weld is an excellent surface for painting and, if you have been careful not to break through the wall of the post, you can even get away with polishing the post and nothing of your repair will show.

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