???Blown Head Gasket???

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I am pretty sure they would have been Cometic. though failures aren't all that common they do happen. We have been using ARP studs to allow for tighter torque but only put 45lbs on his engine. The cams may have put a bit more combustion pressure in there which may have helped it fail. I suggested that he go ahead and put 60lbs on them this time (stock is 30lbs and the studs are rated for 70lbs).

Sean
 
Looks like someone went at the heads with a screwdriver and a hammer.

It really looks like something was bouncing around inside the cylinder just beating the crap out of the heads.
 
Doesn't look like pitting. More like foreign object. Hope your cylinder wall and piston weren't damaged. Would volunteer to drive down and help but I got jury doody. Good luck. Rand
 
Doesn't look like pitting. More like foreign object. Hope your cylinder wall and piston weren't damaged. Would volunteer to drive down and help but I got jury doody. Good luck. Rand

From just a cursory inspection when I pulled the head I didnt see anything glaring on the piston or the walls.
 
Looks like something made it into the combustion chamber. Check the top of the pistons.
Sean

Well dont have any idea what would have made it in there but something did.
Not sure how I got away with this but the cylinders walls have absolutely no marks other than normal wear.
Here is a pic

Could it be pre-ignition or knocking since the cylinder walls were left untouched???
 

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I dought it (MHO) looks like something fell into one of the carbs. you mite want to do an inspection on the carbs see if anything obvious came loose and fell in. i think you just got lucky the object didn't get cought between the piston and cylinder wall.
 
I dought it (MHO) looks like something fell into one of the carbs. you mite want to do an inspection on the carbs see if anything obvious came loose and fell in. i think you just got lucky the object didn't get cought between the piston and cylinder wall.


I just had the carbs off a few weeks ago and they were intact.
Float levels had drifted but all was well.
 
I think that you should take the oil pan off and have a look at that bolt that you say is still in there, you might be suprised at what you might find.
<<Dave>>:punk:
 
Looks like someone went at the heads with a screwdriver and a hammer.

It really looks like something was bouncing around inside the cylinder just beating the crap out of the heads.

That's the truth, what a mess.:confused2:
 
Looks like someone went at the heads with a screwdriver and a hammer.

It really looks like something was bouncing around inside the cylinder just beating the crap out of the heads.

Well this is just a testament to how well Sean builds engines then because the bike was running fine, plenty of power, good compression.
Despite my best efforts to destroy it.
I am going to smooth out the best I can the gouges on the heads, do minor surgery to the piston, slap it together and see what happens.
 
Well this is just a testament to how well Sean builds engines then because the bike was running fine, plenty of power, good compression.
Despite my best efforts to destroy it.
I am going to smooth out the best I can the gouges on the heads, do minor surgery to the piston, slap it together and see what happens.

I am sure you have already considered deck height, gasket thicknes etc. What is the piston to head clearance in assembly? What compression was that cylinder running before the over heating? Have you considered checking for excess rod bearing (big and small end) clearance? Have you considered inspecting the rings on that bank while you have her torn down?
Just curious....
 
Were any of your plugs damaged?
Anything fall in while/if you changed your plugs?

I always clean in and around the plugs before taking them out because some road chips can collect in there and there's always a chance of them getting into the cylinder
 
RM...I think that preignition or knocking can be ruled out as a cause for what happened to your head.

The shape of the gouges and dents (some look kind of like a crater with metal in the center displaced to form a ridge around the edge) certainly look like direct impingement damage from a foreign object.

Sooooo what happened to the object? Did it eventually get beat into small enough pieces that it made it out the exhaust valves?

As far as damage to the cylinder walls, the primary direction of travel of the object would have been parallel to the cyl walls so any blow would have been a low angle glancing blow. The piston and cyl head were the end stops and thus took the brunt of the damage.

I do think that you are lucky that whatever it was did not get wedged between the piston and the cyl wall and wore a gouge in the wall itself.
 
Engine is back together and in the bike.
Assembly went pretty smooth.
Cometic head gaskets and 60 ft/lbs of torque in 4 equal increments.
Just have to finish putting her together now.
Lord willing will be done tomorrow.

HUGE THANK YOU TO DAVE!!!!! and my Son.

Things went much smoother and faster with them helping today. :punk:
 
Well dont have any idea what would have made it in there but something did.
Not sure how I got away with this but the cylinders walls have absolutely no marks other than normal wear.
Here is a pic

Could it be pre-ignition or knocking since the cylinder walls were left untouched???

I wouldn't rule out the head came from a blown V-max engine?
 
I wouldn't rule out the head came from a blown V-max engine?

yeah I am pretty sure it happened while I had the bike.
The piston and head "matched" each other with the gouges.


Hijacking!
Fargo, any work/play with Birdo's bike?

Prezmek,
nope not yet. My upcoming wedding has drained all time and resources.
Gonna start looking at it afterwards.
 
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