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MG MGB Technical - Oil Pan &Timing Chain Cover, Best Way to Seal???

The oil pan and timing chain cover are notorious for oil leaks. What is the best method to prevent the leaks?

1. Use standard paper gaskets without any assist (i.e. as they did in the old days).

2 Use the standard paper gaskets with a gasket sealer/dressing? If yes, which brand and product name.

3. Do not use a gasket at all, instead use a gasket maker such as Permatex's "Right Stuff".

I am interested in knowing the pros and cons, but more importantly, your successes.

Thank you,

Frank Grimaldi
Frank Grimaldi

Frank-
Oil sump gasket leaks develop over time as the gasket deteriorates from both heat and its constant contact with oil, in time becoming a real nuisance. Fortunately, the engineers at Fel-Pro have come up with a solution called the PermaDryPlus® Oil Pan Gasket (Fel-Pro Part # OS20011). Constructed of high temperature resistant, edge-molded silicone rubber on a rigid carrier, it provides a superior fit, as well as both high heat and vacuum resistance, while the included Oil Pan SnapUps speed installation.

Your friendly local speed shop can provide you with gasket material that is superior to any of the waxed paper junk that's commonly available as a ready made gasket. Simply use the timing chain cover as a template and trace around it, then cut it out with sharp scissors. The bolt holes can be made with a puch that you can get at an office suppy store. Coat the timing chain cover gasket with a thin skim coat of Permatex Ultra Black RTV Gasket Maker (not the Permatex Blue RTV or the Permatex Red Ultra RTV). This is possibly the best silicone sealant on the market, able to withstand temperatures of up to 500 degrees Fahrenheit (260 degrees Celsius). Let the gasket cure for several hours before attempting to install it. This will result in a rubberized gasket that will not become saturated with oil and ooze drippings onto your garage floor. Finally, use some Permatex Aviation Form-A-Gasket or Hi-Tack in order to secure it into position on the timing chain cover prior to installation.

By the way, do not be mislead by any product with a term such as “gasket maker” included in its name. This is merely a marketing ploy. There is no reason to feel confident without the structural element of the actual gasket, so never attempt to use any sealant as a substitute for an actual gasket.
Stephen Strange

The most important thing here is to be sure that the area around each bolt hole are not raised or distorted, and are absolutely flat
with the surface of the flange. This goes with both the oil pan
and timing cover.

I use a standard gasket and smear a very thin film of automotive-grade RTV silicone (not household or common
hardware grade) on both sides of the gasket.

Do not over-tighten the bolts or else you'll distort the flange
holes and oil will leak past the area between several bolts.

After a few runs, go back and gently re-torque the bolts a bit.
You may have to do this 2-3 times but it's better to do this in
steps in order to prevent over-tightening.
Daniel Wong

As Daniel implies, overtightening of sump pan bolts is very common and this distorts the flange causing leaks, further tightening simply makes things worse. The flange should have significant flutes pressed in between the holes, and the area aound the holes is also shaped in a particular way. Check the flange is flat, and not bowed. I've used the standard gaskets with a smear of Hermetite red, don't use silicone sealants, especially as gasket replacements, that stuff oozes everwhere. I've seen carb throats lose about 20% of their diameter, and the lumps can break off and circulate.
Paul Hunt 2010

Frank-
I forgot to say that you will need torque settings of 6 Ft-lbs for the 1/4” machine bolts and 14 Ft-lbs for the 5/16” machine bolts. Be sure to not lose the elliptical washers that are peculiar to the timing cover (BMC Part #’s 2K 5197 and 2K 7440). These are necessary for spreading the sealing load evenly across the face of the flange of the timing cover. Keep them paired with their respective timing cover machine bolts as they have become very hard to obtain. Be careful to not exceed the recommended torque values as warpage of the sealing flange of the timing cover is a very possible result.
Stephen Strange

Also, when installing the timing cover don't tighten the retaining bolts down all the way. Leave them about a half turn loose. Install the harmonic dampener to center the cover seal around the dampener. Now, tighten the bolts that you can reach. Next, remove the dampener and tighten all of the bolts. This will prevent the front cover seal from being off center and wearing out prematurely. RAY
rjm RAY

Permatex "Right Stuff".
Oil pan and differential cover.
No gasket, clean surface well, put on a nice bead, snug up all the bolts, wait about a half hour, then tighten everthing up.

No leaks yet!!
William Bourne

I've used hi temp axle grease on all gaskets for the past 40 years and Never once had a leak. Why? Well back in the 1970's, oil rigs off Santa Barbara had diesel mechanics on board, 24/7, and all of the ones I talked to told me they used standard, hi temp axle grease on their gaskets. If an engine went down because of leaks, then it cost big bucks to get it back on line. I figured those ol' boys knew somethin'.

All the above comments are excellent on this subject so you can take your choice as to what to do about the gaskets. They will all work satisfactorily since all of the comments are excellent.
Keep it simple.
R Murray

I'm hardly an expert in the matter, but have plenty of experience with my 80 Limited Edition that leaked from every possible point including the transmission. I'm not a fan of the Permatex or other "form a gasket" products. My car had that red stuff sticking out of everywhere (oil pan, timing cover, rear axle, etc) and getting the mess cleaned up is a lot of work. I've ordered many gaskets from Moss Motors and Victoria British. Some worked fine and others haven't. I'm sure they contract for the gaskets at the best price, so you may not get the best solution for every gasket. I have some old sets of Victor gaskets with Beck Arnley part numbers from rebuilding engines back in the late 70s and early 80s and find them to be of better quality and thickness. Thus you're likely better off to get your gaskets direct from a reputable manufacturer. Second, I thoroughly agree with R. Murray's preference for axle grease to assist when installing and have used it for years. Thorougly clean the parts you're "regasketing" with solvent. Soak the bolts in solvent and wire brush the old grease and rust from them. "Blow" out the bolt holes with WD-40 and air if you have a compressor. Fastener experts insist that you never reuse lock washers, replace them instead, preferably with an automotive grade lock washer. Clean and then sand the mating surfaces with a 600 grade, black sandpaper. Daniel mentions "countering" the bolt holes slightly. It's easily done with a standard ball peen hammer head. "Cross tighten" opposite bolts gradually instead of tightening adjacent bolts. I've never used a torque wrench for covers or oil pans, but rely on "feel" with a 8 inch socket wrench. Hope it helps, but must admit my axle cover will have to come off a 4th time and make my own gasket this time, so I'm not 100% successful with this method.
Rick Penland

X2 Right Stuff snug up a little, don't torque, don't squeeze it out and you'll have no leaks. Circle bolt holes! *Clean surfaces*. No gasket necessary. Good luck.
Samuel Sullivan

This thread was discussed between 20/03/2010 and 20/04/2010

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