Rebuilt 71 455. Broke it in and had no problems. Probably ran 20-30 minutes. I had it running for a few minutes today to recheck timing and the usual stuff. Intake bolts,hose clamps,water and oil. I noticed a little oil under drivers side. Got it up in the air and the oil is coming down the dipstick boss on the block. Dipstick is original to block. It goes in the block hard but once its in,it seems loose. I pulled the breathers out of the valve covers to check for excessive blow-by. Nothing there. Any ideas?
Well, obviously, that ain't getting the job done. Crankcase pressure is pushing oil out of the dip stick hole. Why not run a PCV valve?
Well, maybe at 2000-2500 RPM, your header system had it under control. Engines don't run that fast all the time. Crankcase pressure is building up. Over time, that will cause oil leaks all over, and increase oil contamination. I agree, can't hurt to run a PCV.
Larry is correct in that depending how the pan-evacuation is plumbed into the header collector, .... the negative pressure needed may not be present until the flow past the draft tube increases. With that being said, I ran my last 464 with 4-Offenhauser breathers on the valve covers and no PCV and no evacuation system (not that I advocate that setup, I also feel some form of crankcase evacuation is recommended). I had the dipstick that does not use a tube, just seats on the deck surface and mine never leaked a drop, ...... until my breather foam deteriorated and plugged the breathers. So that does raise some concern if the oil level is correct and the rings are fully seated. Larry
I have the same dipstick you're talking about. Does yours have anything under the disc that sets on the deck?
I think I had the same dipstick style, it didn't have any type of o-ring or gasket under the disc. Mine seemed a little loose also, but I never had a problem with it either.
TA 1500 series will cure your ills here.. I Had many vehicles with the old style 400/430/early 455 dipstick, some leak, some don't. The TA Performance reproduction later style 455 tube and stick combo will fix you right up. Talk to them to get the correct one, based on your specific combo. JW
Nope, and it never leaked a drop until the breathers foam filter inserts broke down and blocked the ventilation. But then oil hemorrhaged anywhere it could, including up into my Mallory Comp 9000 distributor, ... then it even leaked out its vent hole onto the top of the timing cover. It's no wonder why I'm designing an over the top PVC/Electric Vacuum Crankcase Ventilation System for the current Street/Strip engine I'm building for Bluzilla. Larry
