Oil Leak on 2704e

Alpha22

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I have a pair of Thorneycroft marinised Ford 2704e engines. Dorset-Dover-Lehnman --- That kind of thing. 1970's vintage.
108hp non-turbo

One of them has a bit of an oil leak..... well...... it's chucking out about 2 litres a day into the bilge when hard running. Is that a leak or a flow??

As always in a boat, access is difficult..... any clues as to where to start looking???? Any obvious or known weaknesses? It is not comming from the filter or the oil cooler.... that is all easy to check.

It is also loosing a little antifreeze into the bilge, but I can live with that as it is a lot cheaper than oil.
 

aquapower

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I have a pair of Thorneycroft marinised Ford 2704e engines. Dorset-Dover-Lehnman --- That kind of thing. 1970's vintage.
108hp non-turbo

One of them has a bit of an oil leak..... well...... it's chucking out about 2 litres a day into the bilge when hard running. Is that a leak or a flow??

As always in a boat, access is difficult..... any clues as to where to start looking???? Any obvious or known weaknesses? It is not comming from the filter or the oil cooler.... that is all easy to check.

It is also loosing a little antifreeze into the bilge, but I can live with that as it is a lot cheaper than oil.

Give engine a good clean then run up so you can see where oil is coming from, could possibly be from rear main seal.
 

omega2

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Remove the oil filler cap, with the engine running at tick over, place hand over filler neck, if the engine blows your hand off you have crankcase compression, could be worn liners, broken rings, valve stem guides/seals, cracked liner, had all the above symptoms over time, Good luck with it, but they do not cost the earth to completely overhaul. If you have a pipe fitting on top of the rocker cover fit a flexible pipe to it and direct into a 5 litre bottle, that will "catch" the oil, and keep your bilge clean'ish, also you can pour it back into the engine. LOL

Or it could be something as simple as the front or back crankshaft oil seal, check under the bell housing and the front drive pulley.
 
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gordmac

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Old Fords leak oil but yours seems a bit much. Where are you losing coolant from? Crankshaft seals are possible, so are head gaskets (water and or coolant?) rocker cover gaskets.
 

Alpha22

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I can't see any evidence of oil from the rocker cover gasket, or the sides, although the exhaust side has poor access. I have a gut feeling it is either sump or one end of the crank or the other. I have attempted to tighten the sump bolts, but they were all as tight as not to move.

Is it possible to replace the timing cover oil seal and/or the rear crank oil seal with the engine in situ???
 

omega2

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The front oil seal is in the the front cover but it has come out and go in from the inside of the cover, remove the belt pulley by putting a well fitting ring spanner on the nut, work out which way the engine turns over and then jam the spanner with a short length of scaffold pipe, spin over with starter motor and then remove the nut, The pulley can be levered off check the pulley journal do not be surprised to find a groove worn into it, a new seal may remedy the fault, but there are firms that will reface the pulley, or a new one will cost about £300! Undo all the set screws and pull the cover off. The oil seal can now be knocked out from the outside in, and the new one fitted from the inside to out. Before you do this check the front inside of engine compartment if the seal is leaking that badly then I would expect to find lots of oil thrown about. The rear crankshaft seal will require the r&d coupling undoing, the shaft pushed backwards to allow clearance for the gearbox to come off, then the bell housing followed by the flywheel, the seal is in two pieces that slide into grooves one on the sump and one on the block, the sump may need to be dropped to do this, again check for oil spattered in this area as well, remove the starter motor and see if it's wet inside the bell housing. The job can be done in situ but it needs a fit young person to attempt it. Far easier to with the engine out of the boat. Are you sure you are not burning oil? what colour your exhaust?
 
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Forty_Two

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Have a look at the engine mounted fuel lift pump. When I had Lehman's one had a warped flange on the pump. Leaked quite a goodly amount of oil.

If I remember right they only have two bolts holding them on so crucial it's flat.
 

omega2

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Have a look at the engine mounted fuel lift pump. When I had Lehman's one had a warped flange on the pump. Leaked quite a goodly amount of oil.

If I remember right they only have two bolts holding them on so crucial it's flat.

You recall correct

+1
 

Alpha22

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They are 45 years old so both burn a little oil and smoke for an instant when opened up ... but not excessive and it clears quickly. I know the oil is leaking out as I have to suck it out of the bilge at regular intervals. It is not splattered around.... I guess I need to get down and dirty and get it spotlessly clean and then carefully watch for the drips.
The lift pump is a good shout....
 

Alpha22

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