marko Posted August 25, 2005 Report Share Posted August 25, 2005 Hi All, I know most TR3A's leak a bit of oil, but how much is acceptable? I've just completed the bare-metal respray and complete re-trim of a cracking TR3A that has been laid up for a few years but seems to have a leak from the rear of the engine - from talking to various people it seems it may be the rear crank seal?? This is an engine out job I suspect or shall I try and sell the car as is obviously letting any potential owners see the wet patch before deciding!! .........anyone interested??? Comments? Quote Link to post Share on other sites
jonlar Posted August 25, 2005 Report Share Posted August 25, 2005 Hi Marko, I don't know the 2, 3 or 3A engine intimately so don't know if it's a seal as on the 6 or if it's the rope type (or even reverse scroll?), but if it's the rope/fibre/leather type, I'd suggest it may re-seal once it's been warmed thoroughly and soaked up some fresh oil and expanded a bit. Quote Link to post Share on other sites
Andrew Smith Posted August 26, 2005 Report Share Posted August 26, 2005 ...........from talking to various people it seems it may be the rear crank seal?? Hi Marko No need go to wobbly and sell up. It's easy to check whether it is leaking from the rear of the block e.g. crankseal: 1. Remove the thin clutch cover plate on the underside of the bellhousing and look to see if the flywheel is covered in oil; you could also remove the starter motor to be doubly sure, but that’s real pain in the arse! 2. If there is oil on the flywheel, it could be one of two things; firstly the crankseal as you suspect or secondly the camshaft core plug (it was this little bugger on TRK recently). If the latter, it's a simple job but you have to whip out the gearbox and remove the flywheel to replace the plate; but you will have to do this to inspect the crankseal anyway 3. If it is the crankseal, this is more time consuming but I believe you do not need to take out the engine but can just drop the sump and crankshaft - Argos (aka Moss) do an uprated crankseal (TT1032/S) and one is fitted to TRK without problems But before going down either of these routes I would advise checking the easy to see/fix things first. It could simply be blowing back when driving from say a leaking filter head/oil filter (you didn't say whether you were using your 3A?) or other simple to fix area(s) such as a new felt seal on the dipstick, or even just a loose oil breather pipe – are the stay brackets fitted? Also check it is not dripping down from the rear of the rocker cover due to a leaking gasket. Good luck and let us know what the solution was. Regards Andrew Quote Link to post Share on other sites
rudi Posted August 26, 2005 Report Share Posted August 26, 2005 Marco, in case you are driving the car the oil leak may as well come from the front of the engine (as already mentioned by Andrew). I had a leak at the timing chain cover/crackshaft seal. When driving the oil was pushed under the car from the sump to the clutch cover plate over the exhaust up to the diff. Although the amount of oil lost was not that big, after a drive the oil was dripping all over the garage. Hence, I would start to check for oil on the chassis from the front of the engine to the back to really see where the leak starts. I do not know if it was your intention to sell the car after restoration, but in case you feel you should sell her because of the leak, that would be a pitty as most oil leaks can easely be cured. Maybe adding a botlle of "leekstop" in the engine oil might cure the evil as well as this will "expand" old gaskets. Good luck, Rudi. Quote Link to post Share on other sites
marko Posted August 26, 2005 Author Report Share Posted August 26, 2005 Gents, thanks for the replys up to now The car hasn't been run up the road only ticking over in the garage. The oil drip is definately coming from the rear of the block above the sump gasket, although the flywheel is completely clean of oil!! So it somewhere at the back..... Quote Link to post Share on other sites
Andrew Smith Posted August 26, 2005 Report Share Posted August 26, 2005 ....... coming from the rear of the block above the sump gasket, although the flywheel is completely clean of oil!! So it somewhere at the back..... Then it is definitely not the crankseal, cam cover plate or the clutch oil seal. Check the rocker cover gasket as suggested above and also have a look at the rear of the cylinder head gasket - although if the latter, you would probably have traces of water in the oil; have you checked for this? Not too many palces left at the rear. Quote Link to post Share on other sites
rudi Posted August 26, 2005 Report Share Posted August 26, 2005 Marco, an important question: Did the engine run in some point in time without loosing oil? If so what did you do to the engine since? Is the cranck case breather pipe fitted properly? Other things to check: - are all bolts that go in the oil galleries in the block fitted and fastened. - Is the oil pressure pipe that goes to the gauge properly fitted? Clean (degrease) the engine and run it. If oil comes out of the block you should be able to trace the exact spot I guess. Again good luck and let us know the results. Rudi Quote Link to post Share on other sites
Trevor S Posted August 26, 2005 Report Share Posted August 26, 2005 On the TR4 engine (assume 3a is the same) there is a bolt on the back of the cylinder head opposite to the battery slightly to the near side. Some use it for an oil feed tube to the rockers. If this bolt is loose or missing oil would run down the back of the engine when engine is running, so suggest this is checked also. Good luck. Trevor. Quote Link to post Share on other sites
Don Elliott Posted August 29, 2005 Report Share Posted August 29, 2005 The breather pipe which comes out near the petrol pump has two slots cut in it with a hack-saw. This was done at the factory to keep it from falling out. But the slots will let oil leak out. I suggest you take it out, clean it up and use silicone caulking to seal it all back into place. Up front there is at least one of the bolts holding the generator bracket to the block that is drilled and tapped right into an oil passage. Make sure they are tight or they will leak oil. If possible caulk these also when you re-install them. As for oil or no oil on the back side of the flywheel, I suggest that there will never be any oil on the back of the flywheel because the centifugal force will spin it off. When I restored my 1958 TR3A from 1987 to 1990, I put in new seals for the rear bearing as per the original design. It leaked oil so when I did the lead-free petrol conversion 43,000 miles later, I took the crankshaft out, had it ground and put in a new modern rear main bearing seal. It still leaks. I never saw any oil on the back of my flywheel. So I assumed it may come from the front bearing seal for the input shaft of the gearbox. I have replaced this and it still leaks. A TR3A friend from Texas told me that if you compare several dip sticks, they will all be different so he keeps his at, or just above, the bottom line. Now I do the same. I've done this for 3 years. But it still leaks. But I don't worry about it. I add about a liter of 20W50 Castrol every 600 miles or so. I just drove "TRusty" 730 miles over the last 5 days and that's what I had to add when I got home. My TR doesn't leak oil. It's just marking its territory. Don Elliott, Original Owner, 1958 TR3A, Montreal, Canada http://www.britishcarforum.com/ubbthre....ortdir= Quote Link to post Share on other sites
Tr4Tony Posted August 29, 2005 Report Share Posted August 29, 2005 Mark Also check the three bolts along the oil gallery on the distributer side of the block. The middle one is often used as a tap in / replaced by an oil pressure switch - similarly the take off for the oil pressure pipe or on the joint by the fuel pump - these often leak if damaged. Lastly if the gearbox has been out and the engine left in, the rocker cover often bears on the battery box and therefore either gets bent or just mullers the gasket - this causes a leak down the back of the engine. Regards Tony Quote Link to post Share on other sites
rudi Posted August 29, 2005 Report Share Posted August 29, 2005 Marco, you said that the leak comes from above the sump gasket. Neverteless, I once again would check the seal between sump and block. I remember having an oil leak at the front and at the back of the sump were the flywheel coverplate sits. The amount of oil that can leak from here can be significant. Quote Link to post Share on other sites
jonlar Posted September 9, 2005 Report Share Posted September 9, 2005 Hi Marko, have you resolved the oil leak issue, if so - how and what did you find amiss? Quote Link to post Share on other sites
rudi Posted September 13, 2005 Report Share Posted September 13, 2005 Yes Marko, let us know what happened meanwhile. I am curious to know. Cheers, Rudi Quote Link to post Share on other sites
marko Posted September 30, 2005 Author Report Share Posted September 30, 2005 Hi Gents, Well the car has gone in today to pull the engine out and have an unleaded conversion and rear crank seal (still not totally convinced it is causing the problem) - one thing to note is the car is running at 75+psi oil pressure when warm - this seems way to high and I wonder if the pressure is too much and pushing the oil out of the back seal - anyway I've bit the bullet!! Quote Link to post Share on other sites
unclepete Posted September 30, 2005 Report Share Posted September 30, 2005 Marko If the Oil pressure is too high just adjust it! On top of the Oil Filter assembly is a screw with a lock nut. Loosen the lock nut and turn the screw anti clockwise to reduce pressure, easy and you can do it while the engine is running. Unc Quote Link to post Share on other sites
marko Posted October 5, 2005 Author Report Share Posted October 5, 2005 The engine is in pieces and it looks as if a core plug was causing the leak - it was weaping and dripping an oil slick onto the deck!!! The head has been sent off for "unleading" and the crank is being ground to enable the rear seal conversion to be done...it also has a lightened flywheel and fast road components fitted (cam etc) - so it should fly once it is rebuilt.... Regards Mark Quote Link to post Share on other sites
Andrew Smith Posted October 6, 2005 Report Share Posted October 6, 2005 ......it also has a lightened flywheel and fast road components fitted (cam etc) - so it should fly once it is rebuilt.... Regards Mark Hi Marko If you going that far and lightening your flywheel etc, you may as well fit a diaphragm clutch conversion - I did, and it makes a world of difference. Regards Andrew Quote Link to post Share on other sites
marvmul Posted October 7, 2005 Report Share Posted October 7, 2005 MarkoIf the Oil pressure is too high just adjust it! On top of the Oil Filter assembly is a screw with a lock nut. Loosen the lock nut and turn the screw anti clockwise to reduce pressure, easy and you can do it while the engine is running. Unc This screw with lock nut is a by pass valve that is always shut when the engine is warm : don't change it to alter the oil pressure of the warm engine. The by pass valve (ball with spring), is only there to protect the oil pump drive when the engine is cold. Without it the oil pressure would be much too high when starting a cold engine. The opening pressure of this valve is about 70 psi, it is set in the factory. I once was told that these valves were originally filled with resine or other stuff to prevent that someone would change the factory setting afterwards. Someone know about this? Quote Link to post Share on other sites
unclepete Posted October 7, 2005 Report Share Posted October 7, 2005 This screw with lock nut is a by pass valve that is always shut when the engine is warm : don't change it to alter the oil pressure of the warm engine. The by pass valve (ball with spring), is only there to protect the oil pump drive when the engine is cold. Without it the oil pressure would be much too high when starting a cold engine. Marvul To expect anything to be still 'factory set' on a 50 year old car is a bit hopeful! The item in question is a pressure relief valve, without adjusting it after, say, dismantling it, putting in a new oil pump, or cleaning out a blockage under the ball bearing, is like not adjusting your timing from new. Different oils have different viscosities, worn engines, worn but still serviceable oil pumps, will all have an effect on oil pressure. As long as it is set at 70psi when hot it will still control at 70 psi when cold, it is only a spring loaded ball bearing after all! It dosn't stop working when the engine gets warm! If it ever was painted with resin it was only to stop people playing with it who don't know what they are doing. Unc Quote Link to post Share on other sites
marvmul Posted October 7, 2005 Report Share Posted October 7, 2005 Unc, I agree that it is possible that on Marko's engine the bypass valve is screwed in too far and should be unscrewed a bit. But otherwise, this by pass valve isn't intended to adjust the oilpressure of a hot engine and it wouldn't be a reassuring idea to know that some of the oil that is coming out of the oil pump is by-passed to the sump instead of entering the oil circulation when the engine is hot. Quote Link to post Share on other sites
unclepete Posted October 7, 2005 Report Share Posted October 7, 2005 this by pass valve isn't intended to adjust the oilpressure of a hot engine and it wouldn't be a reassuring idea to know that some of the oil that is coming out of the oil pump is by-passed to the sump instead of entering the oil circulation when the engine is hot. Better than coming out all over the garage! Seriously though, The setting point for the Oil Pressure relief valve is 'engine at running temperature adjust pressure to 70psi at 2000 rpm'. The valve works all the time, Hot or Cold, especially at high revs its just that you don't notice it. Unc Quote Link to post Share on other sites
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