New Transmission Mounts

[E Rutherford]

This is a FYI "service bulletin" for the installation of the hoop transmission mounts. I have sold more of these to customers than I have installed, but I have installed my share. They have been coming from the same source for years. This year I have run into a problem with the bell housing studs being to long. The first time this happened it caused the engine installation an extra hour (slow to recognize the issue!). Made a mental note of it and installed a new set this week in another car. Checked it with my little straight edge BEFORE installing the engine, sure enough studs were about 3-4m to long. Fixed the problem by grinding them down. Engine went in like butter.

Not sure why this is occurring this year, but it is now SOP to check them before the engine goes in. Hopefully this info will save someone some grief when they are installation the mounts.

ed
klasse356.com

[Harold Singh]

I just did hoop mounts on my C and they worked fine. No issues. Felt much improved and I used the Stoddard parts. There was a cheaper set available by a significant amount. It was from Sierra Madre but I went with the stoddard version. What mounts are you having issues with normally?

[Doug McDonnell]

Thanks for the alert. Now if someone would make the trans mount the same thickness as they were originally. Lots of old threads discuss that the currently available ones are not the same size as originals.

[E Rutherford]

Harold,
I buy from the same vendor that Stoddard buys from. This issue has not always been the case, just recently. Could be just a bad run?

The point of "FYI" was for anyone, regardless of where the parts came from, to "evaluate" first, then install. Makes for good habits and a lot less grief when working on our beloved cars.

ed
klasse356

[Harold Singh]

Harold,
I buy from the same vendor that Stoddard buys from. This issue has not always been the case, just recently. Could be just a bad run?

The point of "FYI" was for anyone, regardless of where the parts came from, to "evaluate" first, then install. Makes for good habits and a lot less grief when working on our beloved cars.

ed
klasse356

Ed, good point. About how much are you normally having to take off? By that, I wonder if you have before and after measurements. 3-4mm or more seems like a lot! Although in the photos it looks like a good chunk is being ground away.

Thanks for the heads up,

Harold

[Wil Mittelbach]

Now if someone would make the trans mount the same thickness as they were originally. Lots of old threads discuss that the currently available ones are not the same size as originals.

Quite right! Had purchased new (supposedly proper) replacement mounts, only to find they were thinner than the 50+ year old originals in my C car. To minimize engine sag, I reinstalled the originals and discarded the replacements.

[Ron LaDow]

Now if someone would make the trans mount the same thickness as they were originally. Lots of old threads discuss that the currently available ones are not the same size as originals.

Quite right! Had purchased new (supposedly proper) replacement mounts, only to find they were thinner than the 50+ year old originals in my C car. To minimize engine sag, I reinstalled the originals and discarded the replacements.

Wil, got an image of the rear engine tin/surround?

[Wil Mittelbach]

Now if someone would make the trans mount the same thickness as they were originally. Lots of old threads discuss that the currently available ones are not the same size as originals.

Quite right! Had purchased new (supposedly proper) replacement mounts, only to find they were thinner than the 50+ year old originals in my C car. To minimize engine sag, I reinstalled the originals and discarded the replacements.

Wil, got an image of the rear engine tin/surround?

Ron, herewith are photos:-
Again using the original 50+ yr-old original age-compressed mounts (still thicker than the current German sourced replacements) which results in some engine sag. As an accommodation, I used the depicted wider rubber seal alternative between engine tin and engine compartment floor.
Had considered shimming the mounts, which would require modification of the mount's side transmission bolt location.
Sure wish there were original thickness replacement mounts available.
- Wil

[Mike Wilson]

Very tidy, Wil!

Mike

[Jim Liberty]

Brad R. Any comment.

[Brad Ripley]

Jim,

Thanks for tossing this one my way. Below is a drawing of the steel part of the trans mount with the length of the stud noted by the arrow. If you have an original mount, it will be marked with words GIMETALL - GETEFO. Please measure the length of the stud (proud of the metal back plate) -- post your findings.

Ed, out of your endeavors, what should be the ideal length of that stud?

Foot note: GIMETALL was a trademark of Metzeler, the German tire maker. GETEFO was a name of a prior German company specializing in rubber-to-metal bonding.

[E Rutherford]

I'll post the length tomorrow.

[DonCichocki]

How much discrepancy are we talking about between rubber thicknesses from original to the new repros?

[Brad Ripley]

The mounts as I describe above should be considered as Original Equipment (OE) and come from the original German manufacturer direct to Stoddard NLA. I know of no reproductions being made.

As for the thickness (width) of the rubber, in the past some guys have suggested that the Karmann bodies were slightly different and that engine on those bodies "hanged down" more, creating a gap. Anyone have that theory?

[Jon Bunin]

This year I have run into a problem with the bell housing studs being to long. The first time this happened it caused the engine installation an extra hour (slow to recognize the issue!). Made a mental note of it and installed a new set this week in another car. Checked it with my little straight edge BEFORE installing the engine, sure enough studs were about 3-4m to long. Fixed the problem by grinding them down.

The studs should be 20mm long. That was the original dimension.
I measured about a dozen old mounts that I have here- the majority are 20mm, a few are 21mm. None extend into the path of the flywheel.