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MG MGA - Black Gunge

Hello,
I have a little problem with my MGA which you might be able to help with.
Black gunge is being spread over the area near the fan belt - the belt itself,
the fan blades, the pullys, the underside of the bonnet etc. If I touch the
belt my fingers come away just covered in black. It is greasy but it doesn't
seem to be oil as such. Obviously the fan belt needs to be changed as everything
is covered in this stuff (I can push the pulley round with one of the fan
blades with just one finger) but I don't want to do it until I know where
this stuff is comming from. Any help would be appreciated.

Phil
P Parmenter

I don't really know, but could it be oil leaking from the front seal onto the belt and causing the belt to deteriorate into the black gunge.

Jeff Schultz

Hi Phil. I agree with Jeff that the front oil seal is likely leaking oil onto the crankshaft pulley. The oil would then make it's way onto the belt, and start deteriorating it. Small chunks of rubber would mix with the oil, and get flung in an outward path from the belt. MGA's originally had felt oil seals that tend to leak if not properly installed. Improved rubber/metal oils seals from early MGB's can be fitted, but you need the MGB timing chain cover and seal to be fitted as a unit. My 1500 engine has a felt oil seal, and was totally leak free for 25 years! If you install another felt oil seal be sure to follow the factory manual installation procedure to the letter. Failure to do so will almost guarantee leakage. Cheers! GLenn
Glenn

Jeff & Glenn,
Thanks for your replies- excuse my ignorance but what and where exactly is this oil seal?
Phil
Phil

It is not really a seal, just a felt ring in the front of the timing cover, just behind the drive pulley.

Jeff Schultz

The seal is located in the timing chain cover, and seals around the crankshaft pulley. The pulley may have a groove worn in it, allowing oil to get past the seal. Another possible problem could be the oil slinger on the crankshaft. If it is not there, or put on backwards (can this be done?) it would allow an excessive amount of oil to the seal area, perhaps allowing some of the oil to get past the seal. I have the felt seal in my engine, and have had no problems with leakage.
Ed Bell

The original felt timing cover seal is like this: http://mgaguru.com/mgtech/engine/cs100.htm

You can switch to a late MGA or early MGB timing cover with rubber seal like this: http://mgaguru.com/mgtech/engine/cs201.htm

If you have a wear mark in the hub of the crankshaft pulley you can fix it with a SpeediSleeve like this: http://mgaguru.com/mgtech/engine/cs201a.htm
Barney Gaylord

Many thanks to you all for your help I have a much better idea about where to look now.
Phil
P Parmenter

I thought an oil seal was an animal washed up on the beach following a shipwreck involving an oil tanker. Am I missing the point? OIL SEAL - device to retain oil, commomnly in an internal combustion engine

Yours

Bob
Bob Greenpeace

This is a little belated, as I think Phil has figured it out already. The black grungy stuff around the fan belt area is most likely debris from a chewed up fan belt due to bent flanges on a belt pulley. Wobbly pulley flanges are instrumental in chewing up a fan belt in short order. See here: http://mgaguru.com/mgtech/cooling/cool_203.htm
Barney Gaylord

I had the same problem. Turned out to be a cracked pully which broke and chewed up the oil seal.
Kris
Kris Sorensen

My 1980 MGB is having a problem that's similar to the one Phil had with his MGA. If I remove the pulley and timing cover to replace the front seal, does that necessitate recalibrating the timing?

Thanks, John
john myers

John,
You will not change any timing unless you remove the timing chain and sprockets. You will need to replace the timing cover gasket.
Ed Bell

This thread was discussed between 22/12/2005 and 08/01/2006

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