sbc inneed of medical attention 911
Hello all. Thanks for yalls time.
Sorry for any bad spelling and or misprints - its late here and im tired + dealing with my 14mth old son.
Iv got a 66 c10 with a sbc 400.
First of let me say Im not trying to half az this or cheap out on this but money is so tight right now....
To make a long story short - When I got the truck I was told it had a oil change and was pretty much ready to go expt for wiring issues.
After addressing the wiring issues I checked the oil (Overfilled but thought nothing of it because the oil was clear as could be)
I fired her up and she had a slight miss. After a few adjustment I could not clear up the miss. I checked the oil and it looked milkish
So I ran compression checks. cylinders 3 and 5 had 75ish psi and the rest all had a even 125.
I pulled the head with the low compression issues - ran it to the shop and had it checked. (Woulden u know - cracked head)
The shop built me a new head for 200$ with all new parts. Durning the time waiting for the head *I dropped the pan to installed a new high volume oil pump* This is when I found antifreeze in the oil.
(I talked with the shop and they said I should go ahead and drop on the new head on and see how the oil pressure does) Since I never heard the engine knock or such.
Got the head home re-installed.
Fired her up and had 50ish psi on cold start- (I have a cheap after market gauge) after running 10 mins I had no oil pressure- I went ahead and changed the oil thinking maybe it had picked up some of the bad old oil/antifreeze mixture.
I used 10/30 the first time this time I used 10/40.
This time I had 40ish at start up and lost oil pressure within 5mins. (This maybe because the first time I started the truck the oil had been in it over night and its been cold here) The oil I put in the 2nd time had been in the house.
I pulled the valve cover to see how well the top end was oiling - this is when i noticed cylender 7 rockarm wasn't moving as much. I checked and recheck my rocker adjustments and the push rod.
Soo now after all this I have a flat cam.
The shop is saying I probably killed a cam bearing when the cam went flat.
Since Iv had all these issues. Im pulling the motor.
I getting a new cam and lifters from summit - Im getting new cam bearings. right around 150ish.
Then Im having the crank turned with new bearings for 150.
Im planing on installing everything myself. - New cam bearings and stuff....
Im having alote of ppl tell me I dont need to vat the engine block -
Some are saying I just need to keep an eye on the oil and change it 3 or 4 times every 200 miles or so for a bit.
Some are saying i could take the engine all the way down and remove all the
plugs and wash the block at a car wash then spray the block like crazy with wd40.
I read a forum wear someone had the same issues. There was people saying vat and others saying its not needed. Some wear even saying what metal was in the engine from the bad cam probably got washed out by the anti freeze.
The shop Im using is wanting 200$ just to vat + 50$ for all new parts.
Then 150 on the crank and 150 in the cam.
I just dont have that kinda money.
I can probably swing the 300 and a little extra for gaskets/oil pump and stuff but thats about it....
Can I get away with not vatting the engine?
When I dropped the pan there was no - metal looking stuff nor was there any on the magnet on the drain plug. There was none in the oil I just changed after the 10/15min run and none in the oil filter.
Please any advice?
Since you are tearing the motor down completely, I would clean it. Not saying to pay your shop to vat it but at least take it to a car wash and pressure wash it. Take it back home and blow out all passages with an air compressor until completely dry then lightly oil the cylinder and lifter bores. Spray the cam and main journals and anything else you are concerned about rusting with WD40 or similar.
Make sure you follow the correct cam breakin procedure and use a zinc oil additive.
Remove the cam bearings before cleaning. Get the main oil passages that run front to back. If only one lobe and lifter was bad, the filter will have caught the majority of the particles. Where the real damage gets done is when the oil filter mount bypass valve is not plugged, it will allow the oil to circulate bypassing the filter- which is stopped up w/the debris from the failed cam and lifters.
Iron rusts before your eyes after being degreased and wet w/water, so use a rust preventative on it asap.
Clean the lifter bores w/a shotgun bristle brush and acetone to rid them of any shellac that has built up- the lifters have to rotate as soon as the engine starts and if the bores are built up w/deposits, the lifters can be too tight. There's almost never a need to hone the lifter bores, but do inspect them closely for burrs, etc., including inside the bores where the oil passage intersects.
Clean the oil pan up under the tray- there will be stuff there from day one. If I was going to have anything cleaned by the shop, it would be the pan.
A couple pages that may be helpful:
• Cam break in
• Adjusting hydraulic lifters
• Valve train points to check
• Valve train geometry
• Valve spring installed height
• HEI distributor info
Cobalt is right on point with this. With all the plugs removed from the oil passages (including the one under the rear main cap) it's something you can do yourself. If you're going to brush hone the bores now is the time before you wash it. Using hotter water will slow down any rusting until you can get it dried off and WD40'd. Then once you've done all this install the cam bearings and oil plugs.
I'm not sure why you're changing cam bearings and turning the crank unless there is specific damage or wear that need to be fixed. Your problems are:
- First, you've got to know for sure where coolant was getting into the oil. If it was only the cracked head and replacement of the head and its gasket corrected the problem that's one down and good to go so far as coolant in oily places is concerned.
- Second, Chevy's ate cam lobes and lifters for many years; this is not an usual let alone uncommon failure. This happens over a long time period while the lobe and lifter grind each other to powder. This doesn't tend to put any debris into the oil large enough to do damage. Changing the cam, lifters and timing set while in there should be sufficient.
- The oil pump, well oil pressure, I'm not sure from your writing what the problem is if there is a problem at all. Engine oil pressure cold should idle about 40 to 60 pounds. Bringing the revs up when cold the pressure should go to 55-65 pounds which is where the relief valve opens and the pressure will go no higher. Hot idle that should drop to 15-25 pounds. When hot you should see the cruise pressure climb to 40-60 pounds by the time the engine is spinning a couple thousand RPMs. If it doesn't hold that kind of minimum pressure there's a problem, usually that problem is worn out main and rod bearings (the replaceable shell part). The crank's main and rod journals could also be worn or damaged with similar symptoms, if it is the replaceable bearing shells are also shot, but the shells can wear out while the journals remain serviceable. You don't know till it gets opened up and things are measured. Installation of a high volume pump is not a cure for worn journals and bearings and is not necessary for a stock rebuild.
When you look at where this could be headed, it may be wiser financially to consider a low level crate 350 like the Goodwrench. As worn out 400's almost always drag you into really expensive repairs. You'll find when it's open the pistons and rings are shot, count on the damper needing replacement. I'm sure the 200 bucks to dip the block in cleaner also includes Magnaflux inspection to see if there are anymore cracks in the casting. This is mighty important as Magnaflux or dye-penetrant inspection is looking for cracks the eye can't see, something old castings are often full off. Such a discovery is the end of the block it's now just scrap iron with an interesting shape. Then you'll have to replace the block. See how this just keeps adding up? When rebuilding an engine, the cheap way out always leads back in. There's just no substitute for doing it right or replace the whole thing. The mass rebuilders or inexpensive new crate motors from GM can get you a totally fresh motor for no more money, if as much, as messing around one part at a time at the corner parts/shop store trying to make an old motor reasonably reliable. this is an estimate you need to make before getting in very deep. That first 200 you spend might be the best money you ever spend. Or forget the situational analysis and just repalce the darn thing.
This has every potential of becoming very expensive. If the engine holds decent oil pressure as I described and doesn't leak coolant into the oil or on the ground, my recommendation would be to postpone the high dollar work as long as possible. Put a cam and a set of lifters in it and call it good for now.
If you do decide to clean clean it up,don't forget the oil pump has to come apart to be completely cleaned as does the oil pick-up.
As far as the Goodwrench solution,since GM decided to out source that to Mexico,I don't see that any-longer as a valid solution.We have have customers bring those to us that they bought before talking to us and the overall big picture is pretty poor.
Thanks guys. The info yall have posted has been very helpful.
oldbogie. Im not dumping antifreeze into the oil no more.
The issues I having now are.
Driver side rear rockerarm isnt moving as much as the rest. (Flat cam)
When I start up the oil pressure is around 50ish if i give it gas it will raise to around 60ish. after running for 10 mins or so it drops to 0. If i give it gas it will increase to 35 / 40 ish.
Theres no misfiring.
No coolent in oil.
compression on all cylinders is 125.
There is no smoking or banging or odd noises. (Theres a light tapping from the area wear the rocker arm isn't moving as much.
I was having the crank turned just to make sure there is no damage to the main or rod bearings.
Thanks for the pic 1gery. Yes they help alote.
Im not sure what to do here. What are the chances of the block it self being bad.
If i give the engine a good cleaning - have the crank turned - new cam and cam bearings installed - new oil pump - what are the chances the engine will be fine?
What should I do?
Is the motor still the stock bore? If so what sort of ridge is at the top of the bore?
Any idea how many miles are on it. The 400 is not original to the '66 so was it a straight swap a high mileage stock 400 or was has it been rebuilt already?
There not much of a ridge but there is a small one. The pistons looked almost new. little bit of carbon build up but not much.
My main fear is getting all this done and there be a crack inside the motor causing the low oil pressure issues.
It's fact everyone has to face sooner or later.The only insurance you have is a build you did yourself with the aid of a machine shop.
Yet the condition your describing does lend it's self to replacing the cam and lifters,do oil changes for awhile in short intervals because of cam break-in and what happened.That is the lowest cost move you could make.If in anyway the mains or rods bearings where damaged aside from normal mileage wear,it would show up in the oil pressure.Btw-don't go nuts with the cam swap.
This is the cam Im wanting to run. Will this be ok?
Summit Racing® Cam and Lifter Kits SUM-K1103 - SummitRacing.com
so the low oil pressure is more then likely from a bad cam bearing caused by the lobe going bad????
Do you think I should or shouldn't go a head and have the crank turned?
Thanks again guys.
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