Wait till you see what I find....

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bschubarg

bschubarg

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2018-07-04 12.59.54-1.jpg


If you have been following some of my threads, you will know that this 318 has the ported 302 heads with a custom roller cam....

Well, I will post pics of my debacle soon....

I have no business working on cars....
 
Too much lift I bet. "custom roller cam" tipped me off. Exhaust side.
 
How did you know it was exhaust side..... pretty perceptive.....
 
bschubarg said:
How did you know it was exhaust side..... pretty perceptive.....
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As the intake opens it follows the piston down the bore. As the exhaust opens the piston is coming up at the valve.

And, IIRC most likely your cam was a bit retarded and that eats up exhaust valve clearance.
 
yellow rose said:
As the intake opens it follows the piston down the bore. As the exhaust opens the piston is coming up at the valve.

And, IIRC most likely your cam was a bit retarded and that eats up exhaust valve clearance.
Click to expand...
IF WE FAIL TO CRY TREASON WHEN WE SEE IT, WE SAIL INTO THE TEMPEST AND LEAP INTO THE BELLY OF THE WHALE. LOOK BEHIND YOU. THE WHALE IS THERE.

True...
 
2018-07-04 13.41.06.jpg


Could of been worse... heads are fine... no bent valves... next up.... magnum heads..... with new cam.....

I'm going broke....
 
bschubarg said:
Could of been worse... heads are fine... no bent valves... next up.... magnum heads..... with new cam.....

I'm going broke....
Click to expand...

I think you might want to check those valves a bit closer.
That sucks man.
 
Why are you swapping heads?? run a thicker head gasket and advance the cam 4 degrees if you can and let it eat! Use what you have already to save money
 
I agree with TB. Make sure you verify the exhaust valves ain't bent.

I'd clean off a piston top, get some clay and slip a head back on with the gasket and see if you have any clearance. You could be real close and as said above a bit thicker gasket and rolling the cam ahead 4 degrees could save you.

As I've said before...real education costs beau coup dollars. The learning curve for this stuff is STEEEEEEEEEEP.
 
You're lucky that the valves just kissed the pistons.............
And that the push rods were the fall guy that took the brunt of it so to speak.
I bet you have a few bent valves though.
And check out your rockers closely!
How many revs were you turning when this happened?
 
And exhaust side lifts are higher in split pattern cams....which I am assuming it is.

Dang... that is quite a collection of bent parts. Sorry to see that, but you are not alone in such 'set-backs' so don't feel bad... the only people who never make mistakes are the ones who aren't doing anything.

Yes, for sure check those valves; the amount of bending in the stems to effect valve seal is so slight as to not be readily visible to the eye. And the pushrods are reeealy bent; there has been a lot of interference.

To YR's point, did you ever find anything about the cam's timing? And what lift do you have in that cam? It is gonna be hard to put the valves into the pistons with the typical 318 pistons so far down in the hole.

If it not just a cam timing issue being waay off.... to salvage this and since it is not high performance and is a low $$ attempt, I personally would think about a field cut of an eyebrow into each piston in situ with a Dremel. You'll get a lot more piston to valve clearance that way than with a head gasket. A .060" depth would be < 1 cc .... and you know exactly where to put it now. The bottom of the eyebrow should be rounded to avoid a stress riser. It would not be hard to seal up the edges of bores with clay or other goop to keep things clean. I bet someone has similar pistons handy to check for the thickness of the top... 3/16" to 1/4" thickness is pretty typical.

But this type of trick has a lot to do with confidence and tool use skills... so consider it with caution. (I've done such tricks in the past and have always gotten away with it....YMMV.)
 
At least you have a reference point now imprinted on the piston if you choose to do the "eye brow" idea!
 
curious as to what the lift on the cam was

1.5 rockers?
 
We had similar issue on 273 while on engine stand thank Christ. Went to set valves(adjustable valve train). Went to set valve clearance while on stand and only get 2 done before it wouldnt rotate by hand. Actually bent a pushrod cuz we put crank sprocket on in wrong spot. We had 3 choices and I put it in the "retarded" position.
Good luck.
 
I had a set of push rods from a ford 289 thanks to the factory nylon teeth over aluminum gear and 150,000 miles. I joked that the bent valves were for a "Canted" valve head. I can not believe that you don't have bent valves, those push rods are way more bent then my 289 was.
 
dadodgekid said:
Why are you swapping heads?? run a thicker head gasket and advance the cam 4 degrees if you can and let it eat! Use what you have already to save money
Click to expand...
You are right. fortunately I have a set of untouched 302 heads I'm installing..... without the milling and protruding exhaust valves... see previous posts...
 
nm9stheham said:
And exhaust side lifts are higher in split pattern cams....which I am assuming it is.

Dang... that is quite a collection of bent parts. Sorry to see that, but you are not alone in such 'set-backs' so don't feel bad... the only people who never make mistakes are the ones who aren't doing anything.

Yes, for sure check those valves; the amount of bending in the stems to effect valve seal is so slight as to not be readily visible to the eye. And the pushrods are reeealy bent; there has been a lot of interference.

To YR's point, did you ever find anything about the cam's timing? And what lift do you have in that cam? It is gonna be hard to put the valves into the pistons with the typical 318 pistons so far down in the hole.

If it not just a cam timing issue being waay off.... to salvage this and since it is not high performance and is a low $$ attempt, I personally would think about a field cut of an eyebrow into each piston in situ with a Dremel. You'll get a lot more piston to valve clearance that way than with a head gasket. A .060" depth would be < 1 cc .... and you know exactly where to put it now. The bottom of the eyebrow should be rounded to avoid a stress riser. It would not be hard to seal up the edges of bores with clay or other goop to keep things clean. I bet someone has similar pistons handy to check for the thickness of the top... 3/16" to 1/4" thickness is pretty typical.

But this type of trick has a lot to do with confidence and tool use skills... so consider it with caution. (I've done such tricks in the past and have always gotten away with it....YMMV.)
Click to expand...

As always you are correct.... exhaust lift is higher, 454/475,.… but I also had the heads milled and the exhaust valve literally positioned above the deck of the head..... don't ask why....
 
Living the dream.... with experience comes knowledge and $$....but I also have you fine folks to guide me through... going to light off a few M-80s for the Fourth of July...My neighbors mailbox has my name on it......
 
"And exhaust side lifts are higher in split pattern cams....which I am assuming it is."
but it most likely shouldn't be
wrong camgrinder using same set of lobes for intake and exhaust
you can use an ISKY tool on those pistons
 
maybe the valves didn't contact the pistons but the trainers bottomed out with too much lift for the head? wiped out a cam and bent the push rods in a Volvo that way.
 
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