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oil leaks

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Donthuis Avatar
Donthuis Don van Riet
Rijswijk, ZH, Netherlands   NLD
Good to know, I once bought a NOS set of those cork MGA gaskets, although my side covers did not leak ever.....
JT is not always right apparently eye rolling smiley

BTW I always wondered why silicone side cover gaskets were first included in a single set together with the (top) valve cover one, but later disappeared from the MOSS offer confused smiley

In reply to # 3889072 by Brightguy When I first pulled my B into the garage last October it proceeded to puke 3 quarts of motor oil onto the floor. The differential axle and pinion seals leaked along with the rear wheel cylinders, as well as the transmission output shaft. Over the last few months I have replaced all the leaking seals and various gaskets. The most troublesome one was the front tappet galley cover. I tried silicone gaskets, set with RTV the night before, used the rear cover to hold the seal in place while the RTV cured, leaked right away. Small MGA cork gasket, couldn't even get it to seat. Finally cut my own out of 1/16" paper gasket, two layers with a thin, but complete layer of RTV on all surfaces. Replaced valve cover mounting bolt grommets, and at this time I have no engine leaks, no differential leaks, only a small tranny leak which I will attend to when the weather warms up.

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ohlord Avatar
ohlord Gold Member Rob C
North of Seattle, N.W., USA   USA
1957 Land Rover Series I "EYEYIYI"
1971 MG MGB
1971 MG MGB "Bedouin 2"
Yes and the overdrive transmission too

"I'm a long way gone down this wild road I'm on
It's gonna take me where I'm bound
It's a long way around"

"These are the days that must happen to you"

RD2 Radar/ Electronic Warfare Technician
Vietnam 1969-1972

MGB engine and overdrive conversion 7-2013 002 (1).JPG    53.7 KB
MGB engine and overdrive conversion  7-2013 002 (1).JPG

Brightguy Avatar
Brightguy David Sippola
Lawrenceburg, IN, USA   USA
In reply to # 3888425 by jseabolt My engine is covered in oil but I think it's due to the valve cover gasket.

I noticed there is a box on the driver's side with a hose coming off of it going straight to the ground. Is this thing an liquid/vapor separator or more like a PVC valve? What is inside it?

Is it worth the effort to remove this box and soak it in gasoline or kerosene to remove any gunk buildup? Assuming the engine is 42+ years old and it's never been cleaned?

I was planning on routing it to the air cleaner. I'm not much on venting oil vapors to the atmosphere. Every car I did this to, my clothing ends up smelling like motor oil after I drive it.

Gasket material:

I realize this is not something that autoparts stock but I work at a chemical plant and have access to GoreTex gasket material. The same stuff used in shoes. If you have an oil leak that you can't seem to seal this stuff will work. Such as a warped oil pan or valve cover or a pitted surface like a thermostat housing.

I made virtually every gasket on my Yugo engine out of this stuff. Everything except for the cambox to head gasket (because it would throw the valve lash off being too thick) and the exhaust manifold gaskets. I think it's only rated to around 600F.

Fiat/Yugos are bad about the oil pan gaskets leaking and one day found a large enough scrape piece to make one out of and now no more leaks.

It's also easy to cut. The other good thing about this stuff is once you make a gasket, you can unbolt it and reuse the gasket over and over. Such as the thermostat housing. If for some reason you wanted to replace the thermostat 50 times, the gasket won't fall apart and can be reused. The reason I know this is we have to replace these filter elements in my my area about once a week and they have been using the same gasket material over and over again for years. And the filter pressure can get as high as 250 lbs.

I'm planning on using this UHF tape for the valve cover, thermostat housing on my differential cover which I did once before on a Ford Explorer. I also used this material for valve covers on lawnmowers. Why factories use this RTV sealant is beyond me. I guess it's quick and dirty. Last time I did a valve adjustment on a B&S engine, it took longer to scrape this crap off than it did to make a new gasket and adjust the valves and get the engine running!

If anybody is interested, you should be able to get this stuff from McMaster Carr.

My turn to learn something.

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Nicecar Avatar
Nicecar Gary (ex "Harv") G
Victoria, BC, Canada   CAN
1980 MG MGB "Red On Red On Red"
James Post #2.
If it helps swell seals, what happened on further oil changes?
Did you add the next time you changed oil? /(though logically you shouldn't need to?)
and if not, can I assume that one-shot solved matters long term?

Bottle has enough for 1.5 changes on MG.

Donthuis Avatar
Donthuis Don van Riet
Rijswijk, ZH, Netherlands   NLD
Take off the oil filler cap and with a running engine put a piece of paper on its valve cover opening. If it is blown away the PCV is hardly working, if it is sucked towards the opening the PCV is OK.
Of course some flapping about of this paper is to be expected on lower revs. Another, more indirect detection can be watching the idle rpm with the cap in place versus taken loose: in most cases a working PCV will get you more air either via the HIF's of in early cars via the PCV valve on the manifold to weaken the mixture and idle will change. But this imethod is less precise... eye rolling smiley

This special seal in the groove of the oil filter pedestal ihas a square profile, fitting tightly into the groove and is sometimes a PITA to remove. Pressing a sharp pin into the material and then lift it upwards often works. Since this ringseal sits so tight and gets so hard, sometimes mechs working on the B think it is not there and mount a second seal on top of the original one eye popping smiley

In reply to # 3888572 by Nicecar "is it possible to make a MG motor oil leak proof?"

I asked this same question here some years ago, and got less than + answers, but I proceeded, and if I have anything now it's truly minor.

Oil filter fits on a housing that attaches to block. The 2" recessed gasket is probably rock hard, and a bitch to get out, but can and should be done.

Side cover gaskets - lots of talk here in past.

Silicone valve cover.

These three things can be done without pulling engine. Another is rear main seal. If you don't have OD (3+4), good idea to source one, and add new seal, and easier to access side covers.

Gerald: How does one ascertain a working PVC?

mgbal Ray D
Adelaide, SA, Australia   AUS
HI : I like to thanks every one that took the time and effort to answer this question.
Some places mentioned about leaks I have never thought of.
The probable out come will be come winter I will take motor and gear box out and do a complete
over haul on both. Give me some thing to do.
Thanks again guys.

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