flesh wound????

[hirk]

I think its nap time for this one. Parts available

 

[nort]

I've got a couple sets of 2.5 pistons, a set of rods and a bunch of other stuff.
Whatcha need?

 

[hirk]

Much appreciated nort!!! Not sure if I will fix it, I have another engine so no rush to do anything with it. It locked up and i have not indexed it to see what the cylinder locks like yet.

 

[hirk]

Can anyone guess at a cause based on the pic?

 

[hirk]

I dont know, the timing was set in july at 23* fixed using a jsre gauge and Iv'e put 10+ hours on it since. Heads are 34cc, I always ran 91 ethanol free mixed at 40-1

 

[thekid843]

I dont know, the timing was set in july at 23* fixed using a jsre gauge and Iv'e put 10+ hours on it since. Heads are 34cc, I always ran 91 ethanol free mixed at 40-1
Maybe overheat?

 

[whipper]

gasket failed? looks like she was doing some sizzling for sure.. haha

 

[hirk]

No over heat and gasket was good. Anyone think it would last 10hrs with lots of wot if the timing was off? It was indexed off #1 @23* with advance mod removed, could it have been off enough to cause this? Does the wash on the others look ok?

 

[gmorgan]

Too much compression and too little octane.

 

[craft1698]

Too much compression and too little octane.

Common for 2.5's to burn #4 look at the bias circuit in the switch boxes. Happens to duel switch box engines even the old in lines with switch boxes burnt # 4 . Bias circuit causes timing to go crazy when it fails.

 

[hirk]

Thx guys for all your imput. I still cant say for certain but its either water past the gasket or the timing was wacked on that cylinder. I was going to fix it after thinking it over but found a small hole on the front half too so I dunno.

 

[FlatOutAlly]

I'd fix it. Then you'll know what you have in it and don't have to worry about buying a crap shoot.

 

[hirk]

Problem is I have the original 150 supermag power head that belongs with the mid/cowl and just bought a complete 200 before it grenaded. I was ready to fix it before seeing the hole but will have to see about getting it welded.

 

[Jr in Jax]

Looks like what I warned about in my head gasket replacement thread. Mark pulled his head gaskets after my problem and his were already leaking and would have wiped out a piston the next time out. I just put 150+ high speed miles on mine at the Suwannee and it now runs as good as ever. The head gaskets are not if, but when....

 

[procomp]

Post a pic of the hole, usually a piston failure doesnt make a hole

 

[hirk]

Very good chance that was it JR, it only had about 60 hrs on it if they were as stated when I bought it. A guy is going to look it over to determine the cause. I will post a pic later procomp when I get a chance.

 

[Lotus 50]

flesh wound

 

[hirk]

The hole is in the center of the pic just left of the throtle arm.

 

[hirk]

Lol one classic clip lotus

 

[Lotus 50]

I assumed that 's what you were referring to by "flesh wound" I hadn't looked at that clip for years, thanks.