ChainHartMachin

Hi. 1st post on the board....

Anyways, my car developed symptoms of a bad head and/or gasket last Sunday (blowing water at first, then steam out the exhaust, also coolant mixing w/ the oil). I quit driving it and inspected all the spark plugs, sure enough the #7 plug was wet and looked like it had been getting steam cleaned.

So I spent any free time I had for the last 3 days tearing it down. Took the head off last night. When I went to loosen the inboard head bolt closest to the oil return at the rear of the block, the bolt simply broke instead of comming out normally like the other 16 did.

My question is... Did the bolt simply fatigue over time and finally loose its ability to maintain clamping force, thus causing water to suddenly leak into #7 cylinder and into the oil return hole?

Also, the cylinder was full of water when I got the head off and there is a little bit of rust at the top of the bore. I can also feel one or two imperfections when I run my finger around the circumference of the bore. Will these two things kill the compression of that cylinder?

Thanks

ChainHartMachin

five7kid

iTrader: (14)

Welcome aboard.

Typically caused by corrosion/poor cooling system maintanence.

Light surface corrosion typically isn't a problem. Pitting can be. Minor imperfections are typical (although not necessarily desireable).

RB83L69

It's possible the bolts had been over-torqued; or the engine had overheated severely at some point in its life.

The amount of rust that could possible have accumulated in 3 days, won't hurt anything. I wouldn't worry about it.

Change both head gaskets. Have the heads resurfaced; just get the least amount taken off of them to return their deck to flat. get the block decks ABSOLUTELY CLEAN; use emery clotch or a 3M Roloc or Regalite pad, and follow it with lacquer thinner or acetone. Vacuum clean up any debris out that falls into the cyls or elsewhere, ESPECIALLY any abrasives. You can duct tape over the cyls and intake valley to keep it out of there.

When you put them back on, use Fel Pro blue head gaskets; use a VERY LIGHT SMEAR of silicone around the water jacket holes ONLY; and use some sort of non-hardening sealer such as Loctite PST or Permatex 300 (NOT silicone) on the bolt threads. Sounds like it might be wise to replace the head bolts too. You can order them from Summit, or get them from your local speed shop, or even from the dealer.

Damon

The bolt could have been cracked and therefore not really applying much clamping force for some time. You go to unscrew it and- SNAP!

If that one's bad chances are that others might have "issues" as well, even though they may look fine. I'd buy a new set. ARP has a real nice set of bolts with 12 point heads and such for very reasonable money. Last set of head bolts you'll ever buy.

DuronClocker

iTrader: (1)

You can re-use ARP bolts? Interesting. My LT1 heads just arrived today. Also, I should use sealant ONLY around the waterjackets, and not everywhere? Which side of the gasket should the sealant be applied to then? Should a sealant always be used on the head bolts as well?

RB83L69

ONLY around the water jackets; not on the fire rings, above all.

Both sides.

Yes, sealer on head bolt threads. They go directly into the water jacket. If you don't put sealer on them, coolant under pressure will leak around the threads and into the oil by way of getting inside the valve cover.

Others have their preferences about how to deal with head gaskets. What I posted, is how I do it; and they DO NOT leak.

ChainHartMachin

Thanks to all who replied for great information.

The previous owners of my car were not too good about cooling system maintenance, it seems. All the water holes seem to have a sort of brownish appearance to them. Are there any good ways to clean them out with the engine still installed in the car?

Is there anything to be gained from cleaning the lifter valley?

Mine is rather sludgy (partially a consequence of oil splashing on the underside of the intake manifold if I remember right) when I compare it to the tops of the heads. The worst of the sludge is on the roller lifter retainer (the "spider" I think it's known as).

I'll definately replace all the bolts w/ ARP bolts, clean the block deck, and have the heads magnafluxed for cracks and checked for warping.

Thanks again!

Damon

Don't touch the sludge in the lifter valley unless it's blocking the oil return holes. If you mess with it you WILL end up getting it into the oil and then bad things can happen. If you rebuild the engine and have it all apart, obviously you want to clean it thoroughly, but not if you're just doing a head/intake swap. It'll create more problems than it solves.

I install head gaskets dead dry out of the package. Yes, tiny bit of sealant on the head bolt threads to prevent leaks. Yes, you can reuse ARP head bolts. I've had my heads on an off probably 6 times with the same set of ARP head bolts. Some engines use "torque to yield" head bolts that are only good for one use. SBCs don't and ARP bolts are definitely not torque to yield type. As long as you don't overtighten them you can reuse them many times. Tighten the head bolts in several steps. I do 30, 45, 55 and 65 ft/lbs on the final pass starting at the center and working to the ends on each step.

Intake gaskets depends on the style you use. If they're just the cheap paper type I typically use, then a thin smear of RTV around the water ports (both sides of the gasket) but nothing else. I'm also a big believer in using a bead of RTV on the front and rear block walls instead of using the factory end gaskets.

five7kid

iTrader: (14)

You might as well cut to the chase and pull the engine. If it wasn't maintained properly, you're just going to be chasing one thing going wrong after another. Oil sludge and roller lifters is a very bad combination. You've already got it halfway apart, the next thing that goes wrong will likely require you to take that apart again.

I say pull it, disassemble, take the block, crank & heads to a machine shop and have whatever needs to be done, done, freshen it up with rings & bearings (very likely will need to be bored, so new pistons as well - meaning the old rods/pistons need to go to the machine shop, too); boiling out the block, new cam bearings, new freeze plugs, should all be included. You should also chase all the head bolt holes with a tap, and put it all together right (including a new oil pump). It's a 350, so it should be worth doing.

If it wasn't properly maintained, you may need a new cam and new lifters. New roller lifters aren't cheap, but used rollers out of an engine that was maintained (just happen to have a set), would be fine to put in with a new roller cam.

ChainHartMachin

I've been considering the idea of rebuilding it since this happened.
I don't really need the car and if you guys think there's a good chance I'll run into another problem requireing disassembly of the motor again, I think I will rebuild it.

I'll post another thread w/ questions related to the rebuild itself.

Thanks for all the responses!

MurcoRS

I gotta agreed with "Five7", you really should yank it and get it completely freshened-up. Sludge in the valley and coolant leaking into the cylinders both point to very poor maintenance... Block cleaning, boring, decking, the rings, bearings, gaskets, pistons, oil pump & pick-up could all be done under $1K if you shop around and ask around...