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Author Topic: Engine Gasket Type  (Read 2317 times)

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Engine Gasket Type
« on: March 21, 2016, 12:43:32 PM »
I have a 1971 MGB, VIN number ending with 243217.  According to the Moss catalog, the VIN numbers for 1971 roadsters should be between 219021 and 232765.  The engine is an 18GK.  The side plates on my engine were leaking, so I looked up in the Moss catalog and found that through engines 18GK, I should use the cork gaskets (296-370), so I ordered these and delivered them to my mechanic.  When he removed the side covers, he noticed that one had a cork gasket and one had a rubber gasket, and it appeared that the correct gaskets were used in each case.

My question is, for a car with a VIN number which falls in between 1971 and 1972, is it possible that the factory might have used one early side plate and one late side plate, on the same engine?  Or is it more likely that someone has changed one of them along the way, and ended up with one of each.

Then, my next question.  If both side covers are supposed to be the same, which ones should my engine take, the ones using the cork gasket, or the ones using the rubber gaskets?

Just for further clarification, the rear side cover on my engine has a groove around the outer edge on the side of the cover which goes up against the engine .  It is obvious that this cover is designed for the rubber gasket, which fits nicely in the groove. The cork gasket will not work with this cover.  Therefore, if my engine is supposed to have cork gaskets on both covers (which is what I ordered originally from Moss), then someone must have changed the rear side cover to a different style.  This is a reasonable assumption, except for the fact that it doesn't seem to agree with your statement that Moss lists a rear cover which could be used with either gasket (for 62 - 77).
Do you have any idea where the rear cover on my engine may have come from?

The front side cover on my engine has a flat surface where the gasket goes (no groove).  While it looks to me like the cork gasket will make a better fit, I would guess that either gasket would work.  This seems to be consistent with Moss part number 460-075 which is listed for both 18GK (cork gaskets), and 18V (rubber gaskets) engines.  It doesn't mention anything about a breather pipe for this part number in the Moss catalog, but my engine has the breather.  Therefore, I assume part number 460-075 has a breather pipe.

Thanks again for any light you can shed on this mystery!

Jack Wheeler
West End, North Carolina


  • chfwrench
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  • MG information: '73 red B roadster
Re: Engine Gasket Type
« Reply #1 on: March 21, 2016, 12:44:33 PM »
It's possible that a previous owners might have used a later cover to replace that was, bent, rusted or lost is not uncommon, but not necessarily in this case.  More likely, just a replacement of a leaking gasket with one that was available.

The Moss catalog lists only one rear cover for 62-77 (P/N 460-050, $9.95) that can use either gasket. The 77-up had a tab on it, but was otherwise the same. It shows as using cork gaskets both for the front and rear covers of the 18GK engine. And, from my experience, that's how the gasket kits come.  I've seen universal kits with a pair of each, but never just one-and-one.

While both major catalogs show to use pairs of either cork or rubber, Moss is the more clearly defined description, being based on engine type rather than year of manufacture, so your car should be using the cork gaskets front and rear.

Moss, Victoria British and the other catalogs produce and carry the most common or universally applicable items or what is readily available in production. In this case, they seem to have gone with what they saw as covering the most MG models. Front covers as well, I only see the later version available.

There is only one rear cover being offered by each of the catalogs.  For Moss, it is the one you have. You might want t check with VB as there's uses the same number for the listings covering 62-64 and 64-70, which would be cork gasket use only.  Call and confirm before ordering.

Finding a used cork gasket rear cover should not be a terrible task either.  If there's no one local to you, try British Miles in Morrisville, PA.  Tom has a full field of parts cars that he should be able to locate what you need from.  His number is (215) 736-900, e-mail: and website .

Let me know if there's anything else I ca do to help you.

Safety Fast!

Art Isaacs

« Last Edit: December 31, 1969, 07:00:00 PM by amgba »
Art Isaacs
AMGBA Tech Staff


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