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MG MGB Technical - MGB, oil pan, no leaks - what's the secret??

What is the secret of getting no leaks from an MGB oil pan gasket? It just defies me! I have tried:

1. Gasket only
2. Gasket with blue silicone sealant.
3. Gasket with black silicone sealant.
4. Gasket with copper silicone sealant.
5. Gasket with Hylomar sealant.
6. Gasket with Permatex sealant.
7. Gasket smeared with grease.
8. Checked oil pan gasket surface and block surface
flatness and any flaws - none.
9. Tightened bolts one.
10. Tightened bolts one, then again about a week
later.

Leaks!!!! >:(

Paul B.
Paul B.

I used blue silicone and the gaskets provided by Victoria (many years ago). No leaks on the pan but I have had problems with the side cover gaskets (cork. I did let the silicone set up till tacky then assembled. I don't know if that is critical or not.
Robert McCoy

I hammer the flange flat, get everything dry w/ lacquer thinner, use Aviation Permatex non-hardening liquid (used to be number 2 but no more), permatex on any bolts that protrude to inside engine as well. NO leaks! The permatex also lets you remove the gasket w/o damage, can use it over when you find you have only the really crappy Victoria ones on hand! Hate silicon seal, found too many engines with gobs of it in oil strainers and passages. Excessive blowby and removal of PCV systems can contribute to leakage, and much of it comes from the side cover or rocker cover, sometimes front and rear plates - runs down the hot engine leaving very little trace.
FRM
http://www.usachoice.net/gofanu
FR Millmore

Try leaving the oil out. =:-)

British cars are designed to leak oil. This ensures that as they are driven airflow disperses a thin mist of oil all over the underside of the car which acts as a primitive but effective rust proofing.

One word of warning though: Just because oil seeps OUT everywhere, do not think that you can top up the oil just by chucking a can of oil randomly over the engine. I have tried this, and it does not work.

James
J Reinhardt

Are you sure its the oil pan . As the lowest point on the engine leaks elswhere will finish up here. The tediuos business of washing the engine with solvent , and then persuading it to run with water in all the ingnition crevices may be needed.
S Best

All the above but don't over tighten the bolts!

I use blue hylomar on both sides of the gasket and make sure the sump flange bolt holes are not dished then just tighten bolts to 4 ft lbs - no more.
Chris at Octarine Services

I have the same problem. I used hylomar and a
decent quality gasket, and the pan was absolutely
oil tight for several weeks. Then started leaking
mainly from the rear.

I'm starting to think that as FR suggests above, I
have too much blowby. I'm using the reverse
breathing arrangement with one-piece side
cover from mgbmga.com, but they warn that
this breathing arrangement may not cope with
excessive blowby. There is a bit of
oil residue in the vicinity of the vented
filler cap.

Check the following thorough discussion of
blowby issues on Triumphs -- note the mention
of oil pan leaks at the beginning.

http://www.teglerizer.com/triumphstuff/emissions/
Ronald

My oil leaks persist from the oil pan no matter what. Next time I take the pan off I'll do as suggested above and make sure the pan bolt holes are not dished and use a whole lotta sealant.

The leak was worse when I had a high output oil pump inst~~~ed :/
Luigi

If the leak is from the back, is it possible that the oil is coming from the rear bearing cap, maybe past that little retangle of cork? Or down from the crank seal, between the rear engine plate and the block?
Mike Polan

To expand on my comments above, locating the source of the leak can be extremely difficult on clean engines. Dirty ones are easy, because the dirt acts as "developer". Engine that are clean and painted with a gloss or semi-gloss paint let the hot oil run off the hot surfaces with nearly zero trace. When it gets to the relatively cool pan it thickens up. I use rustoleum black barbeque paint usually, which is semigloss. Had a Spitfire dripping, and couldn't find it, turned out the rocker gasket had moved (one of those that was shrunk when installed); that was of course the first place I had looked! Use talcum powder or chalk dust to show the oil traces. Ideally, use a "Puffer" like the fingerprint guys on CSI. You may find oil everywhere, in which case, steam or pressure wash and start over, dust again after a good run.
Luigi, DO NOT USE GOBS OF SEALANT!! Especially silicone. It squishes inside and chunks fall off. These can go right through an oil screen and pump, then lodge in some critical oil passage = DEAD engine. The comment re high output pump is one more reason not to use them. If the engine is anywhere close to OK, and the stock pump likewise, it is more than adequate. This is a scam to sell pumps, and pump up parts sellers purses and egos of people who want to think they have "a race car". They are only needed when fools use excessive clearances or on clapped out bearings.
I don't have time to study it now, but the Terglizer piece mentioned appears correct and very sophisticated. It may be a bit much for some. My thoughts on easier and more ordinary options are discussed in some recent threads, "venting gas tank" and "Oil disappearing somewhere"
FRM
http://www.usachoice.net/gofanu
FR Millmore

add an ultraviolet oil dye. You will know for SURE where the oil is coming from. I know you say its the pan, but with the dye it will point you to the specific point on the pan/block. Most shops that do a/c work have a u-v light, if you don't.
Joaquin

I'm surprised no one has commented on the gasket itself. In my limited experience, the paper gasket doesn't fit--until its rehydrated in warm water. After doing much of the above (checking flatness and flattening the bolt holes) I spread a very thin coat of rtv silicone to both sides of the gasket and tighen the bolts in a pattern similar to torqing a head. No leaks, no drips, no errors!

Paul
Paul Hanley

I actually made a proper cork gasket, using the paper one as a template, then used hylomar... so far so good!
Dave Whitehead

Paul, how thick are your gaskets? Some of the gaskets I've bought are amazingly thin and could not possibly seal. I have a complete conversion set from VBrit hanging on the wall of my shop just to show my friends what junk is sometimes sold. They are honestly about the same thickness as a paper grocery bag.
David
David

I was lucky. My tappet cover gaskets were handed to me by Glenn Towery. The cork was twice as thick as supplied with the standard gasket kit.
Paul Hanley

Too funny, thought I was on another thread. Still...
Paul Hanley

The comment re VB gaskets are fun! Someone brought me a set for his B engine - the only one I could use was the head gasket. Every other one had to be cut, trimmed, holes repunched, or was totally beyond hope. And the pan gasket, while not as described, stuck out a half inch all around, looked really amateur. If you guys are using "Paper" pan gaskets, it's no wonder they leak. The originals are about 1/16 or more thick asbestos composition. I also note that VB are especially good at pushing "improved, heavy duty, etc" parts like H-O oil pumps and similar.
FRM
http://www.usachoice.net/gofanu
FR Millmore

Clifton emailed me about something which reminded me of this re gaskets and good parts:
buy everything possible from The Roadster Factory. He only supplies the best possible stuff, he uses it himself, he's picky, and he puts all his profit back into reproducing high quality stuff. Thereby keeping our cars on the road. The majority of the good Triumph stuff available is his doing. Also does MGB - I wish he did more! He has a new version of his main MGB catalog coming out any day, a revised and annotated update of the factory parts book. Call them and ask for one 800- 283-3723 Also, he's the only (major US)one who uses the original part numbers, so that we who know them from old, or have factory books, can look it up that way. His system cross references all original numbers to what is currently available - Triumph, BMC, Lucas, Girling, Lockheed will all go to his current number, which is normally the most universal of the preceding. He started as a librarian.
The last B gasket set I got from TRF was British made by a new company I never heard of - Clough & Wood - it was just like 1966 again, copper cased head gasket and all! And it was about as cheap as the VB trash, less than Moss. I screamed and jumped up and down for joy.
I don't work for them, and they sometimes have supply problems, but they are my first choice on anything they deal with, and it is a real pleasure to get good parts!
FRM
http://www.usachoice.net/gofanu
FR Millmore

Whew Mill- You are an enthusiastic force. Good to hear your zeal! Vic
vem myers

Firstly, buy the best set of gaskets you can get. I use the silicon rubber ones for the oil pan and side covers and there are no leaks, none. I keep my MGB in a garage with a smooth concrete floor and there are no drops under the engine.

Make sure that your pan is flat and level (other than the seal groove) on the gasket mating surface. Lay it on a flat surface and shine a light through the drain hole and see if there are any significant surface irregularities.

Check that the cork seals at the front and rear main bearing cap covers are installed. I had a previous MGB that the DPO had rebuilt the engine on and neglected to install those seals. One pint of oil per every 800 miles was the average. I rebuilt the engine and made sure all the seals were installed and the engine never leaked any measurable amount between oil changes.

Check the crankshaft lip seals on the front and rear covers. It either one is torn or damaged, they can be a major leak source. If they are not the neoprene type, consider replacing them as any other type distorts with age and will leak eventually.

Check that your drain plug has a new gasket on it, especially if it is the crushable copper type. The copper ring type gaskets have to be replaced each time since they cannot be recompressed.

After running the engine for the first 500 miles or so after installing the new gasket, go around all the bolts again and re-tighten them to the torque spec. Make sure you get at those really tough ones that sit just above the front suspension cross piece.

Lastly, check your oil filter mounting plate bolt if you have an adaptor plate installed. If not tightened down hard, it will leak. If you have an early engine with the cannister type filter, make sure there is a new bolt seal on the cannister bolt. This seal hardens with age and doesn't work so well after a while.
Ron Kluwe

It all seems to come back to quality. Quality of materials, parts, and installation. A lot of good info and resources amongst these comments.

My penny's worth is that the composition of the gaskets generally shapes the experience, regardless of sealers and regardless of the absolute flatness of the sealing surfaces. Some gasketing is well made and resistant (impervious) to wicking away oil through its own supporting media (paper, cork, etc). And some is only temporarily resistant, until it becomes saturated.

This is probably one reason why some folks do OK with bonded cork/silicone gaskets vs. paper. Sealers only seal the flange surfaces, but generally do little or nothing about the potential for wicking. As with any part we buy, even gasket materials are not all created equal. It is the reason I no longer use a paper gasket between the thermostat housing and the head ~ only Permatex Ultra Blue silicone. The silicone sealer fills the small gaps and seals the joint, even under modest pressure such that there are no leaks, which is more than I can say for my previous experiences with any number of paper gaskets in this application.

I am NOT advocating that all gaskets can or should be done away with, but I am suggesting that the "quality" of the materials used to create gaskets ought to include what they are made from and even their mechanical construction. In my not so humble opinion, some materials are doomed to failure by the expediency of design (cheapness to produce) and then speeded along by improper installation.
Bob Muenchausen

It's starting to sound like the real problem
is that newer cardboard oil pan gaskets don't
work well (wicking, as Bob M. explains.) FR
says the original pan gaskets were asbestos, which
explains why they're no longer available.

Ron K. recommends "I use the silicon rubber ones for the oil pan " Who carries a silicon rubber oil
pan gasket? Or do you mean just use a silicon
rubber "gasket maker" like Permatex? Thanks,


Ronald

These are solid silicone rubber gaskets, orange in color and I cannot remember the name of the manufacturer (it has been 4 years since the engine build and on a good day I can remember what I had for breakfast).
Ron Kluwe

AFAIK, the only lower end gasket set that includes orange rubber gaskets for the engine side covers are the sets produced by Clough & Wood (CLW).

I just pulled a CLW set from the shelf and the gasket pan is definitely not rubber. It is a very thick paper/cellulose based gasket with a weird black/blue coating on the surface. The gasket itself is a bit thinner than 1/16 of an inch... so quite a bit thicker than the paper ones I have seen and that was commented on above.

CLW's products tend to be of good quality, comparing well to gaskets produced by Payen but for about 30% less the cost of a Payen gasket kit.

Kai @ Wishbone Classics
Kai @ Wishbone Classics

This thread was discussed between 18/05/2004 and 25/05/2004

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