My 327 blew up!!!.....or did it?

Bruce Dorsi · September 06, 2004, 02:43:50 AM

Quote from: "Pep"Sounds kinda logical to me as well..Easy to prove. Just take the breather/filler cap off then fire it up. It should fill up fairly quick if its a drain back issue...and quite visible.

I agree, Pep, but at idle the drain-back may be sufficient, as the pump's flow rate is low.

Jack may have to hold the engine at an elevated RPM to simulate road conditions, while watching his oil pressure gauge. ....The increased flow rate of the pump will get more oil up top.

GPster · September 06, 2004, 09:06:14 AM

Just one more idea that I had after chat last night. He mentioned shiwing 2 quarts low on the dipstick one time. It would seem to me that even if the drain-back hole in the heads or miss-placed holes in the head gasket are the problem they might not be all of it. That much oil in the rocker arm area should be high enough to running down the push-rod slots in the heads. There might also be a restriction in the valley of the block keeping some more oil in the area above the cam and lifters. GPster

SKR8PN · September 06, 2004, 12:48:23 PM

Midnight..is it possible you have a combination of problems? If your dipstick/oil pan is "out of calibration" a bit, add the fact that the engine MAY be using oil at speed,AND maybe a quart or two is trapped in the valve covers AFTER your extended run...........
Food for thought

Pep · September 07, 2004, 02:02:12 AM

Quote from: "Bruce Dorsi"
Quote from: "Pep"Sounds kinda logical to me as well..Easy to prove. Just take the breather/filler cap off then fire it up. It should fill up fairly quick if its a drain back issue...and quite visible.

I agree, Pep, but at idle the drain-back may be sufficient, as the pump's flow rate is low.

Jack may have to hold the engine at an elevated RPM to simulate road conditions, while watching his oil pressure gauge. ....The increased flow rate of the pump will get more oil up top.

There are two option then Bruce....do it at a fast idle sitting, or drive it around the block a few time until it happens, then quickly jump out and rip the filler/breather off and shine a torch..hmm

...flashlight in. Thats depending on if there's not a baffle stopping that. Probably is. I'm not familiar with Chevs..now if it was Ford, I'd lift the dizzy out, plonk in oil pump drive , stick it in the drill, in reverse....easy......Now that's on option, throw out the Chev and stick a Ford in it...I did

GPster · September 07, 2004, 09:41:25 AM

Another (dumb) idea. If the "smog control" wasn't plumbed collectly or was malfunctioning, could there be enough pressure build up in the crankcase to keep the oil from draining back down to the pan. I know it seems un-likely but a 327" could have been a "road draft tube" motor or a "smog pump" motor combinations of late/early heads, late/early intakes and factory/after market valve covers may confuse the matter more than I can. GPster

old32 · September 07, 2004, 08:03:14 PM

This seems like my ideal motor.

Down Under its illegal to dirink and drive, with this one you can drive 49 miles, pull over, down a stubby or two while the oil drains back down and then off again for another 49 miles and repeat the performance.

Sounds like the problem is up the top somewhere, nothing to do with oil pump, pump drive or pan. Is it a new engine or used? Obviously to lower the oil level the oil must not be returning to the sump. Is it on the heads or in the valley (run her for a while and pull a rocker cover and watch your feet)?

Dave · September 08, 2004, 06:36:56 PM

he had around 12lbs of oil pressure. He didn't want to run it that way, even though they say a sbc will run on 7lbs,

I ran a 283 with 5lbs and it never gave any trouble and it ran good. It had a lot of bearing clearance but at an idle ya dont need a lot of pressure anyway.
Dave

midnight sun · September 08, 2004, 08:43:22 PM

Quote from: "GPster"Another (dumb) idea. If the "smog control" wasn't plumbed collectly or was malfunctioning, could there be enough pressure build up in the crankcase to keep the oil from draining back down to the pan. I know it seems un-likely but a 327" could have been a "road draft tube" motor or a "smog pump" motor combinations of late/early heads, late/early intakes and factory/after market valve covers may confuse the matter more than I can. GPster

Im doing a little more investigation in that area. The motor is indeed a "Road Draft Tube" motor. I removed the draft tube and plugged the hole. The heads are double humpers. I also did go with after market Billet valve covers. They have oil filler/vented setup on one side and pcv valve on the other. A guy today asked me if I had removed the canister that normally sits in the intake valley. He said if I did, he thought that might be a problem. I told him to be honest I couldnt remember. I think I did remove it but will remove the intake and check it out. The intake is an Edelbrock Performer.

I also removed the #1 rod bearing today. It took quite a beating and scored the crank as well so out comes the motor.

I want to thank everyone for their opinions/thoughts on this.

Later

Land Yacht · September 10, 2004, 05:42:39 AM

I had a 283 I ran low on oil by mystake, at higher rpm the oil pres dropped to zero, valves started rattling, let off and press came back up, my oil was probably sitting in the valve covers then drained back down while at idle, just wasn't enough reserve in the pan to keep the pump fed.