224cc Predator carnage

[karl]

Well, good news I did not do anything wrong. Bad news, engine is destroyed.

Only had bout 3hrs on her, billet rod, mod2 cam, 1 to 1,3 ratio rockers, PVL flywheel, 20lb springs, ect.

She let go and snapped the exhaust valve at at over 50mph. Also found out it broke the juggernaut driver (POS)
It did not even lock up, the driver broke before the engine failed, did not lock up (no relation)
Anywho on to the next one...

 

[Dingocat]

That was a nice one to look at. Thanks again for the hemi parts. Lil rupp will like em.

 

[Denny]

Wow! Looks like you could use a good mechanic. What went first the clutch or the valve head?

 

[panchothedog]

On your clutch I can't tell for sure how much damage there is but if it's only the center section called the " spider " it is replaceable. Mine broke and I bought a new one from Go Power Sports for $12. It's a little bit of a wrestling match to get it in but it works like new again. If it were to break again I would fix it again for $12.
As far as the dropped valve, I already feel MUCH better for buying the stainless steel valves for the three higher RPM engines I've built. Sorry for your carnage.
Is there anything worth saving?

 

[Denny]

I’d like to tease Karl some more but I just don’t have the heart. I’ve been in those shoes before. Nothing he did wrong just a bad part or two. Lived that misery with some big block Chevys in the mid 80s.

 

[karl]

Wow! Looks like you could use a good mechanic. What went first the clutch or the valve head?

The clutch broke before, but was still working, just did not want to disengage all the way. Don't
worry I got a good set of tools

On your clutch I can't tell for sure how much damage there is but if it's only the center section called the " spider " it is replaceable. Mine broke and I bought a new one from Go Power Sports for $12. It's a little bit of a wrestling match to get it in but it works like new again. If it were to break again I would fix it again for $12.
As far as the dropped valve, I already feel MUCH better for buying the stainless steel valves for the three higher RPM engines I've built. Sorry for your carnage.
Is there anything worth saving?

Need to file down some gouges , but I might just put a gx270 on it. The regular comet 30 series drivers handle torque better.
It's questionable, Im probably going to condemn the rod, the block might salvageable. Also got the stock monster moto 212
engine that can go back on it, with 28/32mm head with stainless valves, 275 cam, ect , so rebuilding the 224 is not a priority.
But I appreciate the advise!

 

[Denny]

How did it run before it broke? Did it feel strong? I think if it still had a stock rod the damage would be worse. Don’t know if I would trust the rod either. By the way when you play doughed the valve clearance to the piston how was it?

 

[karl]

Very good! Always started right up, and did not notice any loss of power until failure.
Happened real quick in the 6k zone. The cast rod for sure would have let go and may have ruined the block.

The valve-piston clearance, well was quite safe. Stock head and gasket, over .20 clearance.
With the price of fuel now, burning cheaper gas was welcome.

 

[madprofessor]

Sorry for your engine demise, and the cost of replacing it. Wondering if a good break-in period and really wringing out the stock engine before modifying would have revealed a problem while the exchange warranty could still be used.

 

[panchothedog]

Assuming those were the stock valves, it was just probably more than they could handle. For the same reason we change rod and flywheel, the O E M
parts have their limitations. Now we all know what the 3rd weakest link is.

 

[65ShelbyClone]

You can tell it's a stock valve by the raised letters on the head. Typically they are two-piece where the head is friction-welded to the stem.

 

[karl]

Yep, stock valves. Broke where the head meets the stem.

Live and learn.