QuestionQUESTION: hey brad!hello let me tickle your brain"i have a 1950 chevrolet styleline deluxe that i personally built it has a 216ci inline six ,..here's the issue: i had the block decked and over size,.when i bought the gasket kit i saw a two piece rope style seal,..well i said to my self this engine does not have much oil pressure so i guess it's o/k so i continue to put together the engine inserted new crank bearing's plasti gauge every journal lifter crank once again and set ,..rear main seal on to block as told by the manual sat crank back down and set lower piece on to rear main cap again as told by manual,..finished job installad my engine two weeks after cause i was also in process in building the manual trans ,..any how here is the thing after installing the engine .two days after driving veh my rear main starts to leak by the third day its pouring so i do my reseach and find that for 1954and up there is a two piece rubber seal with the same journal diameter so i bought it,..next day i installed it and here is how i did it removed oil pan with engine in veh!remouved rear main cap ,pulled the rope seal with pick and just slide the new up dated seal,..after everything back together drove veh every day for 1 hole week and guess what?yeep its starts to leak at this time i'm so frustated i dont known what to do,..i've already checked all oil plugs behind block since then i've installed also another graffite inpregnated rope seal an the same oil leakage ,..OH and not just seepage i mean pouring to the point that all of my hard work and under body paint hasa been ruin! any ideas on what to do?i've spend over $5k to get this dame veh to were is at,..
ANSWER: A couple of things come to mind. First the rear main seal is only to get rid of the little bit of oil left over after the slinger on the crankshaft spins the main part of the oil into the groove in the rear main cap that is between the main and the seal. That great amount of oil then drains out of the hole in the bottom of the cap and back into the pan. Make sure that hole is clear and not blocked. Second, did you check the end play in the shaft? One of the center mains has a flange and the bearing has a flange and it controls the fore and aft movement of the shaft. Standard transmission cars wear this area out due to clutch application. Then make sure that some one doing a regrind on the crank did not machine off the flange on the crank that acts as a slinger.
Brad
---------- FOLLOW-UP ----------
QUESTION: just a thought!would it matter in any source if the rear main cap drain port where to drilled a little over size to help with the drainage?,...OH and the crank has no rear oil slinger.I've found another oil seal from a chevrolet 396ci with the same rear journal diameter with double lip would you recommend to use it.
ANSWER: Do you have a high pressure/volume pump in this engine or have the oil pressure relief spring stretched? have you checked the oil pressure to see that it is about 15 PSI at road speed? Specifically the oil pressure recommended is 14 PSI at 40 miles per hour. Let me know.
Brad
---------- FOLLOW-UP ----------
QUESTION: no brad,no high pressure oil pump I installed the original style and have not checked oil pressure with actual gauge but the gauge in dash shown about 15 to 17 psi when hot while runnig and about 4 or 5 psi at idle when hot ,..yesterday i checked crank play it has .0035 of play on the dial indicator ,..when i pull the engine out anything in mind of what to check?
AnswerEnd play is fine as is the oil pressure. Before you pull the engine check the crankcase venting system. The road draft tube has an oil liquid vapor separator and it dawned on me that back in the day that used to plug up and the crankcase would build pressure. We used to take that tube assembly out of the block, soak it in gasoline, and set fire to it to burn the goop out of it. And yes I am that old that the 1946 Chevrolet was a new car at that time. Other than that we are back to the oil slinger on the rear main journal. Keep me posted at geezer34nh@yahoo.com.
Brad
