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Triumph TR3 - Oil: Cleaning up the Exxon Valdez

Ok...let's talk about oil...a lot of oil...

My '61 TR3A deposits more than its fair share of crude after each run, and I'm considering recycling. It doesn't just mark its spot, it completely dominates its territory.

Having owned two Triumph Bonneville motorcycles, I understand the propensity of British engines to leak a bit of oil. But what can be expected for the TR? How tight can I reasonably expect to make things down there, or at least stem the heavier flows and prevent having the Environmental Protection Agency come knocking at my door? Short of pulling the engine and reassembling everything, are there other measures that can be taken? What are the more notoriously offending sources of leaks?

Putting down a clean piece of cardboard will usually reveal about 8 different drip points distributed along an 18" line from roughly under the radiator on back.

On the other hand, the undercarriage is completely rust free thanks to the constant application of oil.

From the deck of the Valdez,

Bill Stagg, Captain
1961 TR3A
Bill Stagg

Some Ideas How to Reduce Oil Leaks on a Triumph Engine

by Don Elliott

There have been many technical articles written on this subject, notably by Ken Gillanders of the Triumph Register of Southern California.. Some of his suggestions may be repeated here.

Check the gasket where the fuel pump is mounted to the block and verify that it is not leaking.

Check that all the fittings for the oil line that feeds the oil pressure to the gauge on the dashboard are really tight.

Check the up and down oil breather pipe coming out the block near the fuel pump. It must be sealed leak-proof. So they wouldnt fall out, Standard-Triumph sawed across the tubular end that fits into the hole in the block. That was to make them "tight" but it makes them leak. I took my MIG welder and welded the saw-cuts closed and filed off the excess till the O.D. was smooth and round. Then I used red Loctite 515 Gasket Eliminator sealant on it before putting it back in. If you don't, oil can leak out between the block and the pipe.

Have you a leaky oil seal at the rear of the block where the crankshaft comes out where the flywheel is attached ? Take off the clutch slave cylinder and remove the half round cover at the bottom front of the bellhousing. See if the rear of the block is dripping. If the back of the flywheel facing the block is oily, you definitely need to put in a new rear seal.

Consider one of the new modern technology rear seals. I had my crank re-ground in the spring of 2000 and put in the new technology rear crankshaft seal. The crank has to be removed from the engine to be ground at the rear end for the new seal. There are several stories about the wrong diameter. There are at least two suppliers and one increased the seal size but forgot to up-date the instruction sheet so the had no sealing effect on the crank because the seal was not sealing tightly enough on the crank for that diameter. At one time, the other supplier had the seal too tight for the new crank diameter. The gap where the "endless" spring holds it together would not close because the re-grind diameter was too large and oil would flood out the gap. Make sure you get the re-grind diameter right.

I found that my oil pan bolts were always loose. It always leaked oil. I put in new Grade 8 lock washers and the oil pan bolts still got loose. I filed the flange flat. A good idea, but the flange got even thinner and flexed between the bolts and the gasket leaked more. So in the spring of 2001, I took off the pan (and the oil pump body for clearance) and traced out the oil pan outline onto a piece of 14 gauge (0.078 " thick) mild steel sheet metal plate I bought for about $5.00. I jig sawed all around the outside. Then I cut four large holes for the curves for the four inside corners using a round saw-cutter on my drill (like they use to cut out holes in wooden doors when installing door handles). Next, I jig sawed the inside to give me a steel thing that looked like an oil pan gasket. But I made it 1/4" wider (all on the outside) than an original gasket. Make sure the inside is exactly like the inside contour of a regular gasket not to cause interference with the oil pump body and elsewhere.

After matchmarking and drilling the holes for the pan bolts, I bolted this new piece onto the old flange of the oil pan. Then I took my MIG welder and welded short sections of the new piece to the old flange on the oil pan. The new flat piece makes a nice triangular fillet area that can be filled with welding material all around the inner edge of the oil pan. Do the welding in short sections not to warp the work. And let it cool a bit between sections. Then I ground off all the excess "overhang" weld material inside not to hit the oil pump body, etc. After hand filing the surface of the new flange so it was flat and removing all the burrs, I now had a really rigid flange that would not warp and which was 1/4" wider than before on the outside and flat all over all the way to the inside not shaped and curved away like the original flange.

For about $20.00, I bought a roll of gasket material for oil pans at a NAPA store and cut out a new gasket 1/4" wider to match the new wider flange.

Before fitting it, I reinstalled the oil pump body and checked the pan with the new flange and gasket for clearance around the pump housing and also around the area for the rear oil seal pieces. I stuffed new felt packing, heavily loaded with dark brown liquid gasket goop (Permatex Aviation Form-A-Gasket Part No. 3H), as described in the workshop manual into the square gaps around the rear seal housing.

I used red Loctite 515 Gasket Eliminator on both sides of the new wider oil pan gasket and bolted it all together. So far, it hasn't leaked.

If the plug at the rear of the block at the back end of the cam-shaft has been out or replaced, the cap for this could be leaking.

Wrap flat white teflon tape around the tapered pipe threads on the drain plug and screw it back in securely.

Another reason for a leak at the rear of an engine block is if the front gearbox seal is leaking. Oil will get all over the inside of the bellhousing and drip off the bottom of the cover and off the slave cylinder bracket. Gearbox oil stays fairly new looking while leaking engine oil is black. Another way of finding out if this is the reason is when you check the oil level in the gearbox (hopefully you do), the oil level will be low. If you dont check it, you risk serious damage to the gearbox if your are losing oil. Another way of finding out if this is the problem is when enough oil from the front gearbox seal has seeped into the clutch lining and your clutch starts to slip.

Check that the vertical pipes where the pushrods pass through on the head next to the spark plugs are not leaking.

Check that the seals for the oil filter body are not leaking at the top or at the bottom.

If you have an oil leak at the front end of the block, check out the bolts that hold the bracket for the generator. One or more of these are drilled and tapped right through to an inner oil passage and oil may leak out here if the bolts are not sealed and kept tight.

Also at the front end, check around the gasket for the timing chain cover and the seal at the front end of the crankshaft where the fan assembly is attached.

As Ken Gillanders says, a TR that doesnt leak doesnt have any more oil left in it. He also told me that he has seen classic cars at shows that dont drip oil. Its because the owners trailer them everywhere and after the restoration, they left the engine, gearbox, steering box and the differential empty so they could never leak.

Don Elliott

Bill-Sounds like your car came with the optional road oiling&under carriage rust prevention kit. Since the leaks start at the front, the most likely sources are the timing cover seal&gasket. Usually the seal track develops a groove which can be cured with a speedisleeve or polishing in a lathe.Also, inspect the timing cover as the chain or tensioner can wear through it. Other contributors are leaking vave cover gaskets, bent pan flanges,or the ineffective rear seal. Of course the supersoaker of oil leaks is the oil filter housing, if the seal improperly installed. Some club games include a "dirty diaper contest" in which a sheet of paper is placed under the car and the car with the largest oil spots win. At one time Moss sold a large foam pad with magnets that attatched to the pan to deal with the incontinence problem. A lip type seal is available to help with the rear main leak, but it involves removing and machining the crank.

Berry and Don,

On behalf of myself and the rest of the Cartel, thanks for your suggestions and information. You provide a ray of hope for the environmentalists among us.

Time to tighten up!

Bill Stagg
1961 TR3A
Bill Stagg

My wife has the best line on this subject:
"Why don't you just bypass the middle man and pour that oil right on the floor?"
My friendly mechanic has suggested that since I have about six different small leaks, he won't even bother to fix the one at the oil filter adapter. I use about 1.5 litres per month (daily driver) and don't make much of a mess at the company parking building. But I now control the damage at home by having an old, galvanized, dog kennel bottom under the car's offending areas, while in the garage.

Dennis Nelson

This thread was discussed between 13/11/2002 and 24/12/2002

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