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MGB MGB Side Cover Gaskets

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DentonPerry

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Posted this over on the MGE forum with mixed results- I have a 69 B roadster with engine 18 GH WE H xxxxx whis is correct for the car. As far as I know it is the original engine. Ordered the "uprated" silicone gasket set (VC + SC x 2). The old cork gaskets I have (oooolld but unused) fit the front gasket quite snugly but do not go to the edge and the cork fits the groove of the rear cover perfectly. The new silicone side gaskets are both the same size (6 3/8” x 2 7/8” OD, 5 7/8” x 2 9/32” ID) and will fit the front fine if glued in place but will absolutely not fit the groove of the rear. Vendor say they have never had a complaint for fit on these. So, do I have the incorrect gasket for the rear or has a PO replaced my rear cover with one from a different motor?
 
Denton, If your able, post some photos of the covers and gaskets. As they say, pictures are worth a thousand words!

PS, Who did you buy the gaskets from? I use cork gaskets and never had a problem. I clean the surfaces very well, spray the gaskets on both sides with High Tack, wait a few minutes, then assemble. PJ
 
Tried to post photos but forum kept timing out. I had an old set of corks that did fit. Thay're on their now. Purchased silicones from Moss. They're researching.
 
DentonPerry said:
Tried to post photos but forum kept timing out. I had an old set of corks that did fit. Thay're on their now. Purchased silicones from Moss. They're researching.
Click to expand...

You'll probably have to reduce the size of your photos by at least 50%. PJ
 
Denton, this may be "the long way 'round" to get a non-cork proper seal but if you get a Payen gasket set (likely you'll have to get the entire conversion set) the red rubber seals for the covers have been in there and I've never had an issue with those. The cork ones and RTV would be my second choice. Maybe I'd use the silicone ones, but my jaundiced eye would likely cause me to go back to the first or second choice if the fit is as you describe.
 
Got a correct red rubber gasket from Gordon/B-Hive today. All is now right with world. It is smaller than the one included in the set no matter what anybody else says. Rear Side Cover.JPG
 
The problem, or leaker is normally the rear lifter cover, it being nothing more than stamped thin sheet metal, tends to get over tightened, and warps over time, lending itself to not seal very well. The front factory cover with the crankcase breather in it is much more rigid and tends to be less of a problem. I like to use the flat cork gasket on the front cover. Another source of leak for the lifter cover is the retaining bolt, it is designed to use a rubber grommet and cup washer which captures the grommet, often the cup washer are lost, and not used. Any type of crush sealing washer used on the rear cover has to have a small enough OD to fit the flat section of the rear cover around the bolt hole, if not, it's not going to seal, I have use smaller OD copper crush washers on the rear covers. Hope this helps
 
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Thanks Hap. I appear to be one of the lucky ones in that my cup washers are in place and I have a good selection of o-rings for the bolt/cup washer. This started out with my receiving 2 identically sized gaskets it a kit where my covers are NOT the same size. I didn't know if I received incorrect gaskets or if a PO had swapped out to an incorrect rear cover. After all the postings and speaking with 'Those That Know" I'm fairly confident I have the correct cover and just received the worng gasket.
 
Yes the cover pretty much stay Continent in size over the entire production run, there were a few changes in the lifter covers, but the sizes stay consistent,and the gasket should never have changed. I Only use Payen gasket sets,and they have the correct tow gasket in the set, the flat cork one for the front cover, and the rubber one for the rear,and they come with extra rubber one, so i accumulated quite a few spares over the years. Who knows maybe I have something lying around in my spares that can help you out, if so you can have them for flat rate shipping cost, just give me a call, if I can help
 
Thanks Hap. I'm good on Gaskets now. Supplier says they rarely, if ever have had a complaint regarding the silicone gasket set. Unless I just got one that had the incorrect gasket in it I find that hard to believe. Anyway, I just picked up a pickup truck full of parts from a former MG owner. Had a Silicone front and two rear corks in the pile. With the rubber gasket for the rear I picked up from Gordon on Monday I think I'm good to go.
 
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