Michael Charalambous 12 Posted December 16, 2017 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 Share this post Link to post Share on other sites
SPArKy_Dave 8,826 Posted December 16, 2017 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. Share this post Link to post Share on other sites
deankxf 20,231 Posted December 16, 2017 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. 1 CHESTNUTXE reacted to this Share this post Link to post Share on other sites
CHESTNUTXE 7,259 Posted December 17, 2017 was the new main seal lubricated before start up ? sometimes they can burn out. Share this post Link to post Share on other sites
hendrixhc 10,918 Posted December 17, 2017 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. 1 deankxf reacted to this Share this post Link to post Share on other sites
Michael Charalambous 12 Posted December 18, 2017 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. 3 SLO247, deankxf and hendrixhc reacted to this Share this post Link to post Share on other sites
bear351c 10,260 Posted December 19, 2017 Silastic wont stick to oil, so use thinners/prepsol to clean heads and rocker covers. Must be squeaky clean. Is the oil coming from the front of the trans.? 2 Michael Charalambous and stockesp reacted to this Share this post Link to post Share on other sites
Michael Charalambous 12 Posted January 17, 2018 yeah the oils coming from the front of the trans fixed the rocker cover leak but still has a slight drip when car is warm any ideas could it be the box? Share this post Link to post Share on other sites
bear351c 10,260 Posted January 17, 2018 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.) Share this post Link to post Share on other sites
Michael Charalambous 12 Posted January 27, 2018 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? Share this post Link to post Share on other sites
deankxf 20,231 Posted January 27, 2018 Stop leak usually starts working in about 30mins of running time in my experience Share this post Link to post Share on other sites