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Thread: WTF Causes this?

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Posts: 11-20 of 21
2014-07-21 19:07:34
#11
Originally Posted by 1fastser
As for the sheared off oil squirters...the piston skirts probably did not have the provisions made for them. (?)


They do have the recesses for them but not sure if they were in the right way. Didn't notice until after they were out.
2014-07-21 20:07:40
#12
I wonder how much larger that diameter hole is where the squirter is broken...and if that had any adverse effects.(?)
2014-07-22 17:54:21
#13
Increase flow, lower op you mean? It doesn't "look" to be that much. I need to get the better pics taken but Ive been working late this week.
2014-07-23 19:28:31
#14
Originally Posted by Mattick22
Increase flow, lower op you mean? It doesn't "look" to be that much. I need to get the better pics taken but Ive been working late this week.


yes...larger hole might not have done much 'squirting'...and it definitely wouldn't have been underneath the piston.
2014-07-23 20:15:33
#15
Looks like detonation to me, the oil squirters been broken like that could also mean they installed the piston backwards or put the wrong piston in. They never double checked they just dropped them in and said all is good lol.
Last edited by BenFenner on 2014-07-24 at 18-39-16. Reason: No need to quote the first post and all the images.
2014-07-23 22:51:01
#16
rings were washed out or incorrect gap, oil control ring isnt doing its job from the looks of burned oil remains between top and second rings, as for eaten away top ring land thats is from severe detonation poor fuel piss poor tune, not enough fuel too far advanced timing, im sure your top of pistons look like salt/ pepper and pitting. As for oil squirters, piss poor building, wrong pistons, or pistons facing wrong way. walls look ok, but always possibility that it is out of round from a diy hone job, have a respectable machine shop build the engine.
2014-07-24 12:28:48
#17
Originally Posted by nismo_star
rings were washed out or incorrect gap, oil control ring isnt doing its job from the looks of burned oil remains between top and second rings, as for eaten away top ring land thats is from severe detonation poor fuel piss poor tune, not enough fuel too far advanced timing, im sure your top of pistons look like salt/ pepper and pitting. As for oil squirters, piss poor building, wrong pistons, or pistons facing wrong way. walls look ok, but always possibility that it is out of round from a diy hone job, have a respectable machine shop build the engine.


Yea both motors are going to the machine shop to see if I can get one good motor out of this somehow. I may have to find someone on here to rent a torque plate from if it needs to be bored out. If anyone knows who rents them out let me know as I cannot find the post with the persons username.
2014-07-24 18:40:38
#18
That looks like textbook prolonged minor detonation damage to me. I have a piston in my hand right now with the same exact damage, and it was prolonged minor detonation that did it.
The surface texture alone tells me detonation, but it being on the intake side only really seals the deal.
Last edited by BenFenner on 2014-07-24 at 18-42-26.
2014-07-25 06:50:19
#19
Sweet thanks for the info. Ill need to look up how to detect detonation and probably replace the sensor.
2014-07-25 12:33:06
#20
The minor detonation killed the rings, that let oil seep through and turn to what you can see on the side view pictures as burnt oil clumping around.

Poor engine, makes my eyes rain.
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