Edited because it was embarassing--what with all the hollering and :mad and :cuss and all.


[Modified by The Dude, 10:49 PM 1/19/2002]

 

How much you got in there? Is it just a nice milky film on the inside of the covers or is it literally got water standing all over the place and in the oil? How 'bout down in the lifter valley?

It's not that uncommon when you start up a nice new motor and run it for a awihle and let it sit and cool off over night that you get a lot of condensation built up on the insides of the covers. I've seen it look pretty funky, yet the motor was fine. Especially happens on nice billet aluminum covers and aluminum heads.when humidity is high. If the oil is clean I'd wipe it all out and run it some more. Get it good and warmed up.

Hopefully you'll be Ok.

Don't jump over the cliff just yet buddy!


Jim

 

Over the years I have seen and or heard of coolant in oil for various reasons.It is always good to start up at first with only water because anti-freeze is a deluxe bearing killer.


[Modified by mountainmotor, 11:54 AM 1/10/2002]

 

What am i missing, TAKE IT BACK!!!! if your machinist made a mistake he should stand behind it.I had a slight water seep and all it took was a retorque of some nuts on the head studs, my guy came right to the house! ....redvetracr


[Modified by redvetracr, 10:41 AM 1/10/2002]

 

Okay, slow down.
You being upset is understandable. But relax, the same thing could happen to any 406 in any car.

You need to investigate this. Look at the simple stuff first. Run a vacuum and leak down test. You're looking for something like...oh I dunno...a bad head gasket? If you get a low reading, investigate further. Pull the head. You know, a leaking head gasket could cause water in the oil.

Look at the heads if they've been heavily ported. Look for any over-machining that could have broken into the water jacket.

Look at the intake manifold gasket and make sure you didn't just have a poor seal permitting water to get by down into the lifter valley.

Continue from the easiest to the more difficult in logical steps. It could be something simple. THEN if you DO find evidence of a splayed cap breaking into the water jacket of the block, or a cracked block, or a crack between siamesed cylinders, then you have PROOF of something the machine shop should have caught.

It's winter. Unless you live in the warm states, you've probably got your Corvette in hybernation anyway, right?
This time, go through the investigation yourself. If it were me, I'd want to carefully check every bearing myself, every little detail, even if it means I'm essentially rebuilding it again. You may not even get that far into it.

How badly was the oil compromised? Was it totally mocha colored???
If so, you should change bearings. If it's just a little streaking, you're probably okay. Find the source and fix it.

Vettes are so much better looking than Novas anyway.

 

I tracked down the trouble by pulling the oil pan and pressurizing the cooling system. It was all 6 of the splayed (outboard) studs on the 4-bolt caps.

They were assembled into the block using Teflon (TFE) paste. That looks good on paper but it seems that hot water and/or coolant under pressure can steam clean the stuff right off of ARP fasteners. My theory is because the ARP--and similar--stuff is extraordinarily slick compared to "regular" steel fasteners due to the finish coating. (Probably wrong but it's my theory and I'm sticking with it, dammit.)

Last night I pulled them all, cleaned the TFE off them and ran a tap into the holes to clean them up. I followed up with a 12 gauge shotgun bore brush soaked in laquer thinner on a cleaning rod to really scrub the internal threads and a blast of air from the compressor to dry. I reinstalled them using Permatex No. 2A as the sealer--the stuff I usually use on head bolts and similar. Screwed in the studs a little tigher than finger-tight and torqued the nuts to the recommended spec. of 65 ft. lbs.

Tonight, after letting it sit dry for about 24 hours to assure a good cure on the sealant, I filled the cooling system with water and pressurized it to 17 psi. The pressure held for 20 minutes with nary a drop of leakage from anywhere.

Luckily, this is a brand new engine. I did the 30 min. break-in, changed the oil and filter (assuming the streaky mocha look was assembly lube residue and other junk). Then there was about 15 min. at idle while I set initial timing and tweaked the carburetor. Then I drove it to the car wash and back once and to my office and back once. Total running time on the engine including break-in and timing/carb adjustment is about 1 hour. Total number of oil and filter changes in that time is four. Fortunately the cooling system during this time was NOT a 50/50 mix of coolant and water. It was all water except for a bottle of Water Wetter I used upon initial startup to help avoid overheating while it sat stationary running at 2,500-3,000 RPM for a half hour.

I'm still horny for a SBC Nova or a Deuce, though. That's the next "gottahaveit" car.


[Modified by The Dude, 9:40 AM 1/16/2002]

 

For what it's worth, my 406 did this also. In my case it was the studs seeping water up into the heads. I fixed that with a package of stop leak.

KM

 

So how did you goop up the head bolts? What type a sealer did you use? I think all the headbolt holes in the block lead to the waterjacket and must be properly sealed. So they built the shortblock and you bolted up the heads? I know what yur feelin...been there...done that...hated it....

 

John

I went and got a tube of thread/head bolt sealant from the dealer. I'ts kinda like a liquid teflon sealer, it carries a GM P/N. I use that on all the bolts/studs that hit the water jacket. I'll also just throw a pack of that radiator stop leak stuff in the coolant just too make sure.

KM

 

Did you actually see antifreeze under your valve covers? Or just remenints of something else like condensation or assembly lube? May not really have a problem.

 

Cooling system pressure check time huh?

 

John

If you're question is directed to me, then yes. I pulled my valve covers off to check things after the engine was good and hot and I actually saw the studs seeping coolant. It just kinds bubbled up through and past the washer and nut.

Studs are great, but they may seep unless sealed really good. That stop leak stuff put an end to it instantly.

KM

 

Permatex No. 2A. I've used in on head bolts forever. Good stuff, Maynard. Yes, I picked up the short block, installed it in the car and then bolted on the heads and other accessories in the car. That just works out easier for me given the very rudimentary configuration of the local rental place's portable hoist. The upside to this method is that I don't have to remove the hood--"helpers" for that little job are difficult to come by at 1 a.m.


[Modified by The Dude, 10:44 PM 1/19/2002]

 

#2A is definatly the right stuff for head bolt threads. My manual says to use it on the intake bolts as well.