I have replace rear seal twice using felpro # 40520 this last time I thought I wuold try a new housing also.Fired the motor and after a1/2 hr run time it starts to drip.I have checked everything pcv, breather,crank case pressure and vacuum and cam plugs. And no its not the valve covers,intake, or distributor.I need help
usually those engines use a one piece oil pan gasket. I had a job on an 89 Suburban where, after the owner tried all else, he had me do the pan gasket, and in his case the problem was solved.
I've had the 331 Ford motor in my 27 out 3 times to fix a rear seal leak and it still sits there and drips ! I even bought a duper duty Ford Racing rear seal and it didn't do a thing. I think what I did wrong, and you may have too, is that they tell me you are supposed to put some sealant on the parting lines of the rear bearing cap, and I may have forgotten that step. At some point I am going to pull the motor apart and see what is going on. I only mention that in case your problem is similar. Don
Another thing to consider is the seal surface on the crank. Does it have a groove worn in it? Is it clean? I always clean this surface with some emery cloth and some wd-40 when I'm building an engine. Its also very important to make sure you don't ham-fist the seal when you install it. It needs to be in straight and you have to take great care not to damage the metal body of the seal - sometimes if you bend or dent it when you're driving it in place it can distort the seal lip and cause it to leak. I have been a mechanic and a millwright all my adult life. I have worked on just about every kind of equipment there is and with just as many different types of people as well. Other 'good' mechanics would be surprised (or maybe not) how many people out there that claim to be good mechanics will absolutely destroy a typical lip seal during installation...and think they've done nothing wrong. I had to fix one on a large gearbox on a giant pump in a power plant one time that was just installed a week prior by a reputable gearbox company. When I finally got to the seal they just installed it literally looked like it had been pounded in with a rock. I still have a hard time believing it. lol
First thing its a brand new Gm engine, after the first seal went bad I bought the Gm seal install tool so I knew that it would go in straight and not be damaged.
Did you use that real thin sleeve that you put in the inside of the seal during install? It allows it to slip over the crank without damaging the seal....
no I didn't get a sleeve with felpro seal, is that a seperate part # becouse I havn't seen one with a sleeve.Or is another brand seal?
Did your take off the housing to replace the seal? Did you put some sealer on the outside of the seal. Most of the time it is a leak from the housing gasket or the oil pan^.
Mine came with my felpro kit but didnt come with the seal alone See it here: http://www.store.partsdinosaur.com/product2856.html
Perhaps the seal holder is not concentric with the crank journal that the seal rides on.....is this a typical small block OR is it an LS motor? The seal needs to be concentric with the crank.... Of course, you're sure it is a seal?....right? could it be the seal holder?
Maybe check crankshaft end play. Problem with end play might be allowing crank movement and seepage. Might have been set up wrong with builder.
The motor is a Lt. The end play is .006,I have pics and specs of every step of this build. Next we will try a Gm factory seal,I have had quite a few people say they have had problems with the felpro seal I have done these before with out any problems,this one has us stumped.
Not to be a smart ass but you obviously have not tried "everything". Besides the distributor does not exist on an "LS" Take it apart one more time and DIAGNOSE the leak. Run it with no trans and just an automatic flywheel installed. Clean it completely dry with brake clean then cover the back of the engine with baby powder top to bottom. Start it up and watch for a leak. Once it starts, you can reapply the baby powder to confirm where the leak originates. Clean oil is hard to see on an engine. Oil dye and a black light is even better but the baby powder trick is cheaper.
The Jalopy Journal
