FE Overheated Suddenly Problems Following.

[kdavies3]

Hi Guys, I had a disaster over the weekend.
My 1100 mile engine suddenly cooked itself, no previous symptoms.

Compression check revealed decent compression on the right hand bank.
Very poor compression on 5&6 on the left.
So off with rocker covers.
Holy **** what's going on here then?
On the left hand bank the rocker shaft was loose!!! Not broken but loose.
The Helicoils in the Edelbrock 60069 head have pulled out the rear two completely and the front two partially.
I have rocker studs and nuts already, I'm sure everything was torqued correctly during the build.
The head has been very hot you can see that by the oil staining.
The head bolts were very loose next to no talk at all especially the central ones. (they were all originally torqued to spec.)
The right hand bank looks all OK no heat staining and no pulled Helicoils.
Haven't yet checked the head bolts.
I guess the next thing to find out if the head can be salvaged or not?
I haven't yet checked but it's almost certainly going to be warped as well as the coil problem.
I'm hoping the block is OK and not warped or worse cracked.
No evidence of bore scuffing or scoring I'm pleased to say.
Now it's chicken and egg, did the overheating cause the shaft to pull or vice versa?

Did head gasket go first and start the ball rolling?
I haven't used them myself but I wonder if "timeserts" could be used to repair the threads?

Water pump looks OK, thermostat is very easy to push against the spring I suspect the wax has gone.

Any advice greatly received.
Thanks

[Roush #1]

I am a little confused on which engine you have. Is your engine an FE, stroked small block, 383 cubic inch, or old school big block? All of these descriptions are listed.
J

[Rick Parker]

Timeserts are far superior to Helicoils. They are used exclusively by GM for all of their aluminum heads and blocks including valve train and main studs, and head bolts. They are a little more involved to install but are much better once installed.

[Barry_R]

Sounds like you REALLY overheated it - what numbers were you seeing on the gauge?

Could have annealed the head - taken all the heat treat out of it. I've heard of such a thing but never seen it. Likely to be a doorstop if you did....

[Barnsnake]

Edelbrock 60069 is an FE head.

[kdavies3]

Originally Posted by Barry_R

Sounds like you REALLY overheated it - what numbers were you seeing on the gauge?

Could have annealed the head - taken all the heat treat out of it. I've heard of such a thing but never seen it. Likely to be a doorstop if you did....

Hi Barry, I had the same thought, the gauge went around to 140 + before I was able to pull over safely.
The right side of the engine all looks fine.
That's the only reason I can imagine why the Helicoils would pull out.
The engine was running fine other than hot, I wonder if the rocker shaft pulled after I stopped?
I'm thinking that that maybe a new bare head casting may be the sensible way to go rather try a risky repair on a head that may now be soft?

[undy]

What block are you running?

[kdavies3]

It's 390 top oiler block enhanced with Barry Rs' 445 stroker kit.
I've decide to fit a complete new head, bolts, rocker studs etc.
A fail safe thermostat too.

[CHANMADD]

If the one head looks like that, how is the other..?

[Gaz64]

Originally Posted by CHANMADD

If the one head looks like that, how is the other..?

Agree.

Sorry to say, but with a failure like that, I'd be pulling the engine for a full rebuild.

All the alloy may be soft if one head clearly is, and your compression rings will be like fencing wire.

[Frank Messina]

140°+ C? That's 284°F+, and for how long? You'll be very lucky if your troubles are confined to the one head.

Frank