Need input ..big troubles

[cmegga]

Having a major problem. I need some help trying to locate what the damage is.

I recently rebuild the top half of the engine, edelbrock rpm heads, carne com cam, roller rockers and a bit more. Have had the car back only for about 30 days now. I was a bit hard on her this weeked, and broke something I am guessing is pretty seriuos.

This is what shes doing. I can only get it about 3-4 miles after start up before the oil temp shoots straight up and into the red. Once it gets hot the engiine starts to drownd itself out. It makes no power at all once it hot. Unfortunitally I had to drive it about 6 miles to get it home and by that time it was making some very strange squeeking and squeeling. The oil presure has dropped down very low only up to 40 or so on the guage. The odd thing is the oil heats up very fast but the overall engine temp is only about 215-220 , noramally it has been consistant at 195. It is higher then norm, but not near where the oil temp is going.

I can only guess it is something in the bottom half since the entire top half is new. Any guess on what I have done to her, how bad it is or what I can expect to be blown up ???

Any thoughs would be apreachiated as this one is stressing me pretty bad.

 

[Rowdy1]

BUMMER!

Something doesn't make sense, when you say it's drowning itself out, do you mean just losing all power? Did you make sure you used all the right gaskets and such? I have to think about this one for a bit. I would definitely NOT run it anymore until I did some tear downs and inspections.

 

[cmegga]

Yes it just loses power. All gaskets are exactly what edelbrock called for (the Prof-Fel Falttened steel). I am not planning on running it any longer, she going out on a flatbed some time this week.

 

[Rowdy1]

Who Did It?

Did you do the work or did you have someone do it? Did it do it right from the initial start up or did you drive it for a while? If I read your first post right, you were driving it and got a little rough with it correct? First thing I'd do is drain the oil through a chesse cloth and look for metal, if you say it was making squealing noise, you probably scored a rod or main bearing. Then again, you put a new cam in it, very possible it's a restriction in a cam bearing seeing as how you only touched the top end. You did put new cam bearings in right?

 

[sscam69]

If you are going to do the work, this is what I would do.

I would put the car up on stands, drop the oil pan and have a look see on the bottom end. Look for scoring on the walls of the block. I am guessing thats the problem, that sqeaking could be a piston. Thats worst case.

Then I would take off the intake manifold to see of everything is ok on the top.

I seriously think its the bottom end!!

Frank

 

[cmegga]

Rowdy

I had the work done at a speed shop. It ran great when I got it back, I have been fdriving its 3-4 days a week for the last 3 weeks. It has been great until this. I did a complete top rebuild including the cam & lifters .. I am not positive If we swapped the cam bearing or not.

 

[cmegga]

oooch.. hes not going to be able to get her in the shop for a weeks or so.....

Anyone else have an idea of what may have hppened here ??

 

[barrier5]

Have you looked at the oil yet,( if you drain it save it for the shop to see ).If you pull it apart will the shop still backup their work? I'd look at the mains and the oil pump and drive. Good Luck

 

[cmegga]

The oil is clean and full. My first though was the head gasket so I check the oil and coolant. They both look fine.

Oil pump is definitly a good thought as the oil temp seamed to cool down a bit at idle.

It will start a seam to run ok for a few minets before the oil temp start to rocket up. If it was the main bearing woulnt it be maiking some loud noises ???

 

[Jack]

Have you looked at the oil yet,( if you drain it save it for the shop to see ).If you pull it apart will the shop still backup their work? I'd look at the mains and the oil pump and drive. Good Luck

;stupid

Sorry for ya! Sadly, I agree w/ all the others ... I'm leaning toward bottom end. Once pan is off, pull front main brg cap (#1) and rod caps off 1'st crank-throw (cyl 1 & 2) ... look for damage there first ... follow up with remaining caps. Also w/ pan off, roll crank through and as each piston reaches tdc, look at its cyl wall for scoring & at piston skirts when at bdc. Disassemble oil pump ... there should be NO trash nor scoring/galling inside. Save the oil & filter for later inspection.
JACK:gap

 

[barrier5]

Not always,if the bearings pile up they can stay very quite and cause all kinds of havoc.I agree with Jack start at the # 1 bearing and work back,try tapping them with a hammer and see if the sound changes,crude but it works.Myself I'd start with the oil pump,maybe that you dropped the pickup,that would explain the oil cooling at idle(none of it would be sitting up in the top and the pump could draw).Just another shot in the dark.

 

[Stingray72]

I would also look at the oil pump first. The pickup will collect large debris. When I first got my vette, the oil pressure was a little low. We pulled the pickup off and removed a whole bunch of stuff that greatly resembled oil-dry (little pebbles). I'm having a difficult time remembering exactly how we discovered this, but I think we did it when we pulled the engine to get it rebuilt, just out of curiosity. To this day, I have no idea what that stuff was, but I've heard that it could have been pieces of a shattered timing chain that may have been replaced before I obtained the car (I got it with a little over 60,000 miles on it).

Good luck.

 

[Jack]

/Stingray72 ... To this day, I have no idea what that stuff was, but I've heard that it could have been pieces of a shattered timing chain that may have been replaced before I obtained the car

Stingray72:
You probably heard right ... I've experienced it myself ... many factory cam gears' teeth were "jacketed" in plastic. BTW, what happened with your distributor?
JACK:gap

 

[Jack]

/barrier5 ... Myself I'd start with the oil pump,maybe that you dropped the pickup,that would explain the oil cooling at idle(none of it would be sitting up in the top and the pump could draw)

;stupid
I mean this in the most kindly way .... let's hope it is a dropped pickup ... if so, the builder should definately be on the hook for your woes! BTW, after the op pickup tube has been firmly seated (driven home) into the op body, it's good insurance to tack-weld the pickup tube to the op body.
JACK:gap

 

[cmegga]

Thanks for all the feed back , I guess Ill just have to keep my fingers crossed and hope its the oil pump pickup!! Not sure Im in a position right now to throw too much more money into this thing.

 

[mmvette80]

I hate to tell ya this but last year I had a new cam and lifters installed. About 5000 miles later BOOM. I guess the new lift is too much. I drained the oil and it came out silvery. :cry

 

[Stingray72]

Jack, now that you remind me, that was exactly what I was told. The pieces in the pick-up were plastic, which bothered me to no end until I learned about the use of plastics on timing gears to keep them quiet.

About the distributor: I got the replacement a couple weeks ago with no problem. I've put about 100 miles on it so far and I've had it on the highway once for just a few miles. I didn't want to post about it for fear of jinxing myself. Before I installed it, I pumped some extra grease in the tach drive. It took one and a half pumps. They come pre-lubed, but when I removed the seized tach drive on the first distributor, I saw that there was quite a bit of open space around the drive gear. Maybe that's why it failed.

I've been driving around like a paranoid grandmother with a distributor wrench in one of the rear compartments. The first distributor seized when I had put a little over 100 miles on it, so if this one makes it to 150, I'll start relaxing. The car sure does run great with this system. I also have to give MSD credit for designing the tach drive to fail in the manner that mine did, because I was able to get out, re-adjust the initial timing to the approximate correct location, and drive it home with no damage to the engine, tach, or anything else.

 

[69MyWay]

Let's think this through. The bottom end was untouched. That means that either a cam bearing has bit the dust, or there is some kind of debris in the engine causing you problems. It is highly posssible that the pre-assembly lube he used on the new cam and rockers has worked its way down into the oil filter, or oil bypass valving, and or on the pick up of the pump.

I have had the pick up fall off before on my 85 383 stroker motor. The difference is, from the start up, it would loose oil pressure when you hit the brakes hard (sloshed oil forward in the pan), turned corners, or accelerated hard. When you drove nice and easy, it ran fine and had plenty of pressure, or would return to normal as soon as I pulled off the side of the road to a parked an idle position.

When the pressure drops, the lifters pump down, make an aweful racket, and the engine will feel as if it has lost power.

Now, I have also had an old Pontiac 350 that got some debris into the oil filter adapter. You don't have that on the Vette, but the same concept applies. This car would run great for as many as 30 miles, or sometimes 30 feet, then it would lose oil pressure, make a huge noise, and lose power. The debris was from some upper end mods on the engine I had done, and it got trapped down there and would work up into the oil channel and clog the main feed. After shutting it down and letting it sit for a second, it would fire back up normal and run for an unpredictable amount of time before doing it again.


Now a bad cam bearing could typically cause your oil pressure to spike off the chart. That is because if the bearing spins, the oil hole is no longer lined up and the pressure dead heads. So, if you are seeing hard as a rock oil pressure, and all the other symptoms then that could be your problem.

However, at this point I am with the others. Drop the pan (thank God it can be done in the car on a C3), and clean it out, as well as replace the oil pump and screen. Change the oil and make sure all the preassembly lube is out of there.

You might turn out to be okay.

Also, make sure you use a steel sleeved oil pump drive shaft. It is possible you just have the plastic one in there now. It is even possible that your oil pump drive has slipped, and is grinding and chewing itself to pieces. This could be if the preassembly lube got in the pump and caused it to pull harder than usual adding pressure to the shaft, and causing it to twist. Thus, loss in oil pressure, bad noise, and loss in power due to the loss in oil at RPM.

The one thing that really bothers me is the oil temp. This could be a bad sender, possibly a pinched wire that makes ground when it gets hot. If it is reading accurate however, you may have a spun bearing and the excessive friction is heating it up. Let's hope it is just one of the other above items including a clogged pump causing the oil that does get through to heat up extra due to the limited volume available to the engine.

 

[77-4speed]

5:32 am ?

Geez Chris, you get going early!

Russ

 

[cmegga]

The shop said they used a steel pick up and he welded it into place. I have a feeling thats going to be the problem here. As far as something clogging the pump I ll have to invesitgate that further, that is definitly a good though and I hope its that simple.

I just had it towed in this morning so I should here something back this afternoon. Hopefully it wont be that I need a bottom half rebuild.

If infact that turns out to be the case .. bottom half rebuild. What would you think about rebuilding what I have, opposed to trying to locate a moderatly priced new block ?? I now am kicking myself for not just going with a create motor for what I have invested in it now and dont want to make the same mistake twice.