The Stovebolt Site Forums The Shop Area Engine Shop Lost oil pressure, then coolant

'54 Corvette, Blue Flame Six. Just rebuilt, stock.

Engine builder said to drive it a little and bring it back for a final valve adjustment. Been a little cold, so the first drive was only about 20 miles. Saturday I take it out, everything seems good so I go out on the interstate. About 12 miles into this adventure, I notice oil pressure isn't as high as usual, its just above 30psi at 3000RPM. Keep an eye on oil pressure. It slowly drops over the next few miles. By the time I get off six miles later (having slowed down and prayed pressure wouldn't go away altogether before the next exit), pressure is below 15psi. Get off, drive over the overpass, shut off engine and coast into the gas station. By the time I shut down, pressure is barely showing on the gauge, though it does drop on shutdown. Nice rattle too. Coast into gas station. In the last 10 feet of the coast, coolant starts blowing out the overflow line. Maybe a quart or so blows out. Temp gauge never climbed above 190 or so, but it is a Bourden (sp?) tube type, accuracy unknown. Smoke coming from the vents on the valve cover.

Checked oil before leaving home. Checked oil after disaster. Clean and full both times. No coolant in the oil, still looks new.

Now the thing is sitting in the garage, and still smells really bad two days later. Burned oil smell?

What went wrong?

Did the oil pump fail? If so, do they die slowly over several minutes like that?

The overheating can affect oil pressure, but I doubt that much. A rattle with low oil pressure usually means that there is a bearing gone. Once the bearing has lots of clearance, the oil pressure drops because it is pouring out of the bearing. I would say to you that the rebuilder will probably have a responsibility here. I would get some advice on how to approach it in order to get the best outcome.

It sounds to me like something was left loose. Hopefully not much damage was done. How come you haven't called the rebuilder yet in those two days?

Incident happened Saturday afternoon, he was closed and unavailable. I talked to him this morning, first time he was open since the incident. He is a good guy I've dealt with a long time, and I know he'll make it right. Since I don't drive the car for transportation, he wants to wait and get it back in the shop next week so he can get some other stuff finished he is working on now. I didn't make a fuss about that because he always gives me a good deal and stands behind his work.

howziit guy!

sorry about your misfortune...hope all goes well.

off-topic, but have you considered installing a coolant recovery system?

i know it's not OEM, but your FLAPS has a generic one, selling for under $20(including radiator cap).

it did wonders for my coolant"puking" problem.

Oh, crap. Im so sorry to hear about this!

If the '54 vette engine is like the one in my '54 Bel-Air, the main bearing clearance is set with shimstock between block and caps. If the clearance isnt set right with these shims, the bearings will be too loose or too tight.

What was your oil pressure before this happened? What weight oil are you running?

My bet is bearing failure. If the oil pump was new, and the lines installed right, Im sure it is OK. It is very unusual for a cam bearing to spin or fail, if it was installed properly. A rod would have started to knock like crazy if a rod insert was the culprit.

I'm going to bet that either your #2 or #3 main bearing insert has failed due to improper installation. Drain the oil into a clean pan for inspection. Bearing failure will show up as chips, chunks and ribbons of metal in the drained oil.

Please let us know what happened!!

Chip

54_blue_flame.

Believe it or not, the exact same question was posted on the Inliners message board - word for word. By a user with the exact same user id. Go figure! :confused:

[QUOTE]Originally posted by ftyler:
54_blue_flame.

Believe it or not, the [b]exact same question was posted on the Inliners message board - word for word. By a user with the exact same user id. Go figure! :confused: [/b][/QUOTE

howziit guys!

yup...and at chevytalk.com also.

Hmmmmm, imagine the odds of the exact/same situation!

J/K.

Always good to get more than one opinion . . . I have asked questions on the Inliners site and here - gotten good info from both sites.

No matter who you ask, the same Richard Pryor joke applies:

The motor said F*&@ it and fell out.

chip

Yup, I sure did post the same question multiple spots. Y'all missed the NCRS Technical Discussion Board.

I've gotten some good responses on all. The NCRS Board did come up with something no one else did. A gentleman there told me that there is a 3" freeze plug on the front of a 235 block that should be left out for a Corvette due to the unique water pump (made for the low hood). I know the water pump is unique, 'cause they are $600!

Will let you (and the other groups) know what is found when the pan drops next week. Thanks for the responses.

Blue Flame,
I see you're in FtC, What shop are you working with?

That may address the cooling issue, but the massive loss of oil pressure should not be an effect of pure overheating. Oil pressure won't be that affected by engine temperature unless the engine is REALLY hot to the point of cracking or heat-seizing. This should be especially true in a new (healthy) engine.

Actually, I had two main bearings seize in my '54 sedan engine, due to incorrect adjustment. The engine lost oil pressure and also overheated, due to the bearing failure.

let us know!

chip

I go to Bowers Racing Engines.

Definitely agree that the oil pressure drop was not caused by the overheating. We'll see what shows up when the pan comes off.