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Michael Charalambous

351c oil leak

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hey boys i have a 351 cleveland in my 85 xf  which recently had a rear main seal leak on. I replaced the rear main put it all back together took it for a 20min thrash yestreday all was well with no leaks. Then tonight i took it for a steady hour just cruising along to check everything was ok. When i got home checked under the car there was an oil drip from the front of the bellhousing guard plate (same a rear main) and another was from passenger side extractor (something ontop dripping on the extractor). They were both dripping roughly a drip a minute. The car was still hot and i was slightly pissed off to jack her up to investigate. Tomorrow when i jack her up to have a look do you have any suggestions as to where the leaks are coming from? any help would be greatly appreciated

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You may need to speedy sleeve the crank.

If the rubber edge of a rear main seal has gone really hard, it can cut a small groove into rear crank rotating surface,
this will stop any new rear main seal from sealing correctly - especially as the oil thins out.

Speedy Sleeves are a way to correct the problem.

 

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what kind of oil pressure switch has it got? one for the base model light or a guage? the light ones are common to leak, dont think its a rear main just because oil is at the bottom

could also be the inlet manifold valley cover seal leaking or rocker covers or even sump.. 

if it's leaking so quickly, it should be easy to find if you wash everything, and run it for a few minutes

if it is a rear main seal, try an engine stop leak additive, STP brand one is awesome for rear main seals.

STP_Engine_Stop_Leak_1.2.3_0.png

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I found the rocker cover seals are pain in the fucking arse, specially if you have the cheapy chrome rocker covers.

I replaced the covers with alloy ones and siliconed the neoprene gaskets to them prior to fitting to the heads. Siliconed them, to the heads and put a dab of silicon on each rocker cover stud thread to stop the leak.

It finally worked and no annoying leak from the covers.

 

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Hey guys inspected the car today, the leak has stopped and oil is still full so not to major of a leak. Following the leak up its coming from the passenger side rocker cover so i will replace the gaskets  try get rubber ones and silcone them to stop the leak. If it continues to leak ill jack the car up while the leak is happening to trace it in the act. Thanks for all your help boys much appreciated.

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Is the oil pink or brown.?  Could be the front seal on the trans,  need to drop the gearbox to fix. Depends how much you hate the oil leak.......

Can buy a Trans 'stop leak' fluid, (like the stuff Dean posted above, for engines.) 

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On 1/17/2018 at 8:48 PM, bear351c said:

Is the oil pink or brown.?  Could be the front seal on the trans,  need to drop the gearbox to fix. Depends how much you hate the oil leak.......

Can buy a Trans 'stop leak' fluid, (like the stuff Dean posted above, for engines.) 

hey boys sorry taking long time to do all this just not enough hours in the day between work and the race car 😂😂 the oil is brown i recently got the box all new gaskets put on and front and rear seals fixed so whatever is leaking must be engine unfortunately i put in stop leak but i done my diff worst luck how long does the stop leak take to kick in? 

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