Rear crankshaft seal

[Dudley]

I am puzzled! On stripping my 845cc engine out of a 1972 R4 I found quite a lot of oily grunge in the bell housing. I assumed it must be the rear crank seal. On further stripping I discovered there was no seal, so ordered a new one from De Marco without investigating further. Now putting it all together I note that there is no way a seal can be installed as the crank flange sits proud of the transmission case. There does appear to be an oil thrower alongside the rear main journal. Below are some pics. Any advice please. I am new to Renault restorations I.e. unfamiliar.

 

[Homegrown]

Nice car you have.
It's correct, there is no seals on the crank just French ingenuity.

Homegrown Garage Green One -75

I have some Renaults i will try to make a tread on each. I made tiny presentation on my cars earlier. Green One is supposed to be a daily driver. I used it a lot until engine gave up due to faulty cylinder gaskets with the result of major overheating and sized engine. I from 1975 845cc 800-05...

www.renault4.co.uk

Link to my engine assembly with all torque settings.
Best regards.

 

[JdeW]

A Billancourt engine doesn't have a crankshaft seal. There is a disc with a kind of gear teeth that drives the oil back to the crankcase.

Possible bellhouse oil spill causes are;
1. Oil leakage along the crankshaft in these engines is usually the result of worn piston rings or improperly functioning crankcase ventilation. Too much crankcase pressure or improper suction causes the oil to be pushed out due to the higher crankcase pressure.

2. It could also be that some sediment has collected in the return mechanism in the past and that the blades are full. I take out all the fallen engine and gearbox and investigate. At the engine dismantle the crankcase and inspect the vanes and disc.

3. If it is not the engine oil, you could think of a leaking drive shaft seal. Oil from the gearbox that comes out through that seal leaks through the same hole at the bottom of the clutch housing as any engine oil that leaks past the crankshaft. Remove the sealing plate on the gearbox and replace the seal and gasket.