Reed Jensen

Thanks for the info.... I guess on the ford engines the return area was restricted by the manifold gasket. Those engines to my recollection , had the oil piped up to the rocker shafts. On the chev engines the oil is pumped up the rods... Most of the restriction for oil flow to the upper part of the chev is through the lifters. On the crane roller hydraulic lifters there is so little oil passing that if you run anything thicker than 10-40 they don't lubricate the rocker well enough. But there are "passages" between the lifter areas and the lower crankcase that can collect lots of oil from what is flung off the crankshaft. It may be possible that oil is pooling there, but I'm still skeptical that 10 qts can collect in the rocker covers.

robyw1

it sure sounds a lot like your pump bypass is sticking open. Make sure the pickup is 1/2 inch from bottom of the pan to avoid cavitation and foam

Roby

jhnrckr

Is it possible that the lifter valley can be holding oil under high pressure too? I know that when I switch to a standard volume pump all my problems went away, solid pressure from idle to 5600+ RPMs.

rmbuilder

Washedaway,
When you added the kick-outs did you re baffle the pan, add any diverters or trapdoors?
Bob

Washed Away

Rmbuilder,

No I didn't add any other trap doors or baffles. I did deburr all the oil drain back holes and slots in the block.

I don't know wher this will end in the spring, but some spring time testing is due with oil levels ( a 1/2 to a quart lower on stick), maybe a quick shut down and watching the level rise on the stick. The pressure never seemed to flucuate at crusing rpms (3500-4000). Maybe a return to a stock type pump is worth a try.

Strip Poker 388

iTrader: (6)

On the oil filter bypass we hallway's plugged it. made all the oil run thru the filter ,just careful not to rev motor when oil was cold .I always run the Moroso pumps with the anti cavitation grooves in it. I think mellings new design pumps have this ,they do require a deferent pick up.on my boat blower engine it had 90 psi and never sucked the pan dry even at 7250 Rpm. My Chevelle small block it has 80 psi on the Moroso pump in a 10-12 sec.pass down the track at 7800rpm it does not suck the pan dry.contradiction?Smokey Yunic allway"s said for every 1000RPM all you need is 10psi so 6000 is 60 psi.

On Oil level sounds like might want to run a quart low.see if the crank is picking up the oil .On My Chevelle it has a 7 quart Canton oil pan on it and testing it on the bench with 7 quarts in it it was above the windage tray.even with the oil filter consideration capacity, It might be that close on yours?remember it does not sit level in a boat.

What about the oil pump matting to the rear main cap ,could some be spraying (leaking) out?

I have seen rod side clearance do it. you did say you had to do some work to the rods?

It has to be windage which would make aeration, but what is causing it?

You said it goes down when you let out of it .I don't think this is it but.
On my Camaro drag car it had a Moroso T sump pan on it and when on the breaks hard the oil pressure would go down to 20 psi. so the oil was moving forward in the pan oil pump sucking some air. I bought a Jeff Johnston Billet fabrication oil pan with full kick out ,flat bottom .It looks like a 14 quart pan its so big . I only run 7 quarts in the pan and no problems any more.even with the oil level that low.

TwoKs

Iwas wondering how lifter preload might cause this problem. I owned a 24' panther that had the same problem.Just started it had 65psi warmed up 55psi after a run than idle 10to 15 psi. let idle for 10 to 15 mins and back up to 55 TRIED EVERYTHING MENTIONED in this thread except lifter preload. I always adj 1/2 turn maybe it was never enough. Can anyone explain how that would cause this problem. Never did cure that problem just ran it that way for 3 years than sold boat and that guy ran it for a few more. But it did always make me worry and not enjoy the boat totally

blue thunder

I have had windage problems in the past and they showed as a drop in oil pressure at elevated rpm. Also, when I had windage problem I could smell oil burning as it hit the underside of the hot pistons. It was an unpleasant situation. Well, I have fixed the windage problem, studied the bypass valve plugging option and decided to leave bypass in, buy larger coolers and replumb oil lines to eliminate 90* elbows. I have been having the same problem with oil temps.

Lifter pre-load will not cause oil pressure problems.

Dave

PatriYacht

What windage tray is the best? I presently have Dooley 8 qt. pans with a sheet metal tray. I am considering going to a Milodon screen type with a crank scraper. While this may work well in cars, I'm worried the screen won't control the oil in rough water.

Washed Away

Ya gotta love engines. I've seen stock rebuilds blow up in a week and buddies beaters drive for years without anything but gas and a quart of cheap oil every other fill up. Its gotta be some sort of addiction that makes a person tear into a perfectly good running motor and try to make it better (faster, stronger, quicker). I'll give ya some more background on the engine (block really). The boat has 350 hrs on it. The guy I bought it from bought it at a repo auction with a blown 365 mag. He bought a 330 long block and had it installed. (At appox. 75-100 hrs I believe). I bought the boat and threw a cam and intake on it and ran it for a year. This last spring I pulled the motor and rebuilt to a 496 (cam and intake looked good but did nothing for performance). The 330 ran solid with no problems what so ever. I ran it from the Maumee River to Mienkes West flat out one day, feeling guilty the whole time, but that lo-po motor would only rev to 4600 and never even hurt it (probably a 1/2 hr run).


Oh, on the rod side clearences they were checked and I don't remember the specs but they don't stick out as a problem.