Burnt piston ouch!

[K-DAWG XB 2003]

No I didnt re jet. The side with the burnt piston was 138 to 140. The stbd side is 145 to 150. It has been checked different gauges. I thought if I would have had a lean problem it would have been the STBD side first. Thats why I figured I had a blown head gasket. I guess I am just gonna have to rebuild it or part it out and buy a different power head. I guess I should pull the other head and have a look at the STBD side to. It sux because I was about to buy a motor for my little saltwater boat. Guess I'll be fixing the Ally with that money.

 

[chad202]

If the other side looks good, check for blockages on the burnt side in the water jackets.

 

[brotherxb03]

If you didn't rejet,that what caused it. You should have gone up 2 sizes on the main's. If the cylinder isn't scared and it just has aluminum stuck on it you can use muratic acid to get it out,then lighly hone it. Just honing it will take too much sleeve material out and put the bore over the service limit. That acid is some bad **** though,you will need a resperator and rubber gloves and dont get it on anything but the sleeve. I'v been running 140's compression on a 95,200 carb motor that is jetted, with no problems. Now I have jinxed myself. Mine has 2 size bigger mains,blueprinted exaust chest and boisen reed's which run richer on the hill.

 

[allison8503]

the first thing I thought of when I saw the pics were that it leaned down a little. What was the outside air temp. when this happened. Higher compression and colder air would mean it should take some more fuel. But it aint bad at all. You know its bad when the same time you hear it parts of the motor are hitting you in the back of the head and the only thing you can use agine is the starter not even the cowling cause it looks like somebody shoot it point blank with a shoot gun.

 

[K-DAWG XB 2003]

It was prolly between 65 and 70 degrees outside.

 

[brotherxb03]

If you have stack's or the stock antinuator cover off the carb's that will make it need rejetting also.

 

[Myron]

see this http://forums.screamandfly.com/forums/showthread.php?t=178425

 

[mtolley]

see this http://forums.screamandfly.com/forums/showthread.php?t=178425

That is my buddy sammy's motor, twice now it has popped the same hole, right out of break-in. were still not sure what caused it but are thinking electrical.

 

[HO]

Chad,
How high of compression would you say is safe to run on pump gas? I used to have mine at 145-148psi but would splash it with higher octane since the quality of the pump fuel was not dependable. Have you had success running a higher compression carb'd engine on 93 octane?

John

 

[suicidealli]

should have rejetted with the tighter heads........ all well lesson learned.... if it cleans up, and measures just do a basic rebuild with new pistons.... that really isn't that bad of a melt down.....
jmo

 

[chad202]

I running an EFI motor and around 165-170# and have been for over a year and only running 93 octane. You have to feed it the fuel, more pressure. The absolute limit that I know of is 180# with 93octane.

 

[Fl Boy in ILL]

Chad

No disrespect but 170 on pump gas is asking for trouble and not great advice, unless you are using TK-7 or something similar! I personaly would run over 150-155 on 93 but maybe I am being too conservative? A little octane is a WHOLE bunch cheaper than pistons and a re-nic job. These things are way to expensive. Just my 2 cents!

Rick

 

[chad202]

Rick, I'm not suggesting anyone to do it. Believe me, I questioned it many, many times myself but our buddy Kevin assured me I'm good to go.

 

[Yellowallison]

I have never ran anything over 150-155 with pump gas and sometimes added a splash of 110 if I knew I was turnin it up - runnin it hard.


Seen 180 ran before with pump ....but never had the baLL$ to try it..:big grin


Myself....I like feel of 240-245+ with 112 :shock:


p.s I working along with a few other good folks to help K-DAWG get a ???? motor so maybe he will back on the water soon.

 

[K-DAWG XB 2003]

p.s I working along with a few other good folks to help K-DAWG get a ???? motor so maybe he will back on the water soon.

Well, if things go as I would like them to I will be going a whole lot faster when I hit the water this time around............................

 

[RedAllison]

Well, if things go as I would like them to I will be going a whole lot faster when I hit the water this time around............................

Asheeeeeut dawg, we gonna hafta call him "Triple Digit Dawg" purt soon!!! :beer:

STAND ON IT SON,
RA