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'77 B losing oil

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'77 B losing oil
  This topic is about my 1977 MG MGB
ZimCraft Reid Zimmerman
Pine City, MN, USA   USA
1977 MG MGB "Kermit"
Just noticed much more oil under the car than usual and I'm seeing a drip at the joint between the back of the engine and the front of the tranny.
What am I up against?

Edited 1 time(s). Last edit at 2017-10-12 09:51 AM by ZimCraft.

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LENZ Avatar
LENZ Jim Barlow
Leominster, MA, USA   USA
1974 MG MGB GT "Murphy"
either rear seal of engine or front of tranny. positive not coming from somewhere else?
possible engine/tranny removal

HardlySlept Avatar
HardlySlept Chris Gatti
New Berlin, NY, USA   USA
1980 MG MGB "Blythe"
Could be a new leak! Valve cover, side covers, oil cooler line, etc.

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course2kid Jeffrey Johnson
Fountain Valley, CA, USA   USA
1979 MG MGB "Lucy (Lucifer)"
Given that drip location, the source of the leak could be several places since gravity and or wind while driving will push oil toward that location.

The leak(s) could be between valve cover and head, head and block, oil filter base and block, oil filter to oil filter base, pressure sensor fitting to block, pressure sensor hose to pressure sensor fitting, pressure relief valve to block, front or rear side cover to block, around the heads of the side cover fasteners, timing chain cover to front engine plate, front engine plate to block, timing cover crank seal, rear engine plate to block, transmission to rear engine plate, rear engine crank seal, and probably several other spots that I can't think of.

Of the above, I think the most likely culprits are side covers or their fasteners, valve cover, oil filter base to block, oil filter to its base, front crank seal, or rear crank seal.

The best way to find the source is to thoroughly wipe down the engine, add some engine oil UV dye (available at most autoparts stores), and then idle the car for a while (no driving because you don't want the air flow pushing drips around), and then looking for the leak with a black light (black light flashlights are available at most autoparts stores or you can buy a blacklight bulb at Home Depot or many other places).

lewisrn Avatar
lewisrn Gold Member Bob L
Danville, IN, USA   USA
1980 MG MGB "The "B"
As Jim advises above, oil could be coming from elsewhere, such as the top of the engine. Common oil leaks at the valve cover or tappet covers can migrate down the sides of the engine and sometimes appear at the bell housing/engine junction.

Eliminate those easier possible sources before tackling an engine & tranny removal.

In any debate, the side which strays from civil discussion is usually the side that lacks confidence in its debate position or in its ability to win the debate on the merit of their arguments. Making personal attacks on the opponents instead of staying on the subject is also a sign of weakness.

KenAdkison Avatar
KenAdkison Silver Member Ken Adkison
Shelton, WA, USA   USA
1975 MG MGB
Most any leak in the engine compartment gets blown back to this low point.
If your engine is dirty this is a good time to clean it.

I would not condemn the rear seal crankshaft seal until I ruled everything out by climbing underneath with a can of WD-40, a little brush and a roll of shop towels and wiping off everything until the rag comes away clean. It could be as simple as the oil drain seal but at least you will what was dirty and after another drive and jack stand use any leak will be easier to see.

Sometimes piece of mind is worth the trouble.

ZimCraft Reid Zimmerman
Pine City, MN, USA   USA
1977 MG MGB "Kermit"
Thanks much to all of you.....looks like I have some cleaning and sleuthing to do....

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BumbleB74 Avatar
BumbleB74 William Milholen
Tidewater, Tidewater VA, USA   USA
If you can safely jack the car up, check our oil level in the transmission. My philosophy for my driver is that the leak is very slow, and I have never had to top up either the engine or the transmission......mine is either a rear engine seal leak, or transmission leak.

Oil is cheap.....I drive on (but keep eye on things).

1974-1/2 Roadster, "Bumble Bee", Corvette Yellow - in shambles, wire wheels
1976 Roadster, "Virus", Sandglow - "driver" condition (stock + 32/36 Weber DGEV, cast iron header, 25D distributor), bolt on wheels, ON the road!

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