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  #11  
Old 05-19-2014, 06:12 AM
Def Def is offline
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Keeping the same pistons? They might be ok. If not I can probably help you out there for aftermarket.
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  #12  
Old 05-20-2014, 02:58 PM
Rovch Rovch is offline
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Keeping the same pistons? They might be ok. If not I can probably help you out there for aftermarket.
Depends on the damage, but I am planning on keeping same pistons/rods/rings. Come up with new head/cams, clean the motor, and check bearings - is the plan for now.

Either that or use my 80000 miles KA out of my Kouki which is awaiting LS swap. But then I'll have to daily drive my race car until the swap is done. Decisions-decisions..
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  #13  
Old 05-20-2014, 07:28 PM
Tower240sx Tower240sx is offline
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If worst comes to worst I have several KA heads in Cali...PM me if you can't find one locally, I feel like they aren't worth shipping cross continent.
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  #14  
Old 05-22-2014, 11:05 AM
Rovch Rovch is offline
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If worst comes to worst I have several KA heads in Cali...PM me if you can't find one locally, I feel like they aren't worth shipping cross continent.
I am moving to Cali next year, will keep you in mind
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  #15  
Old 06-04-2014, 04:42 PM
Rovch Rovch is offline
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Finally got to pulling the motor and tearing it down. My finds are shocking and contradictory considering that this is a 500 mile motor. I apologize for crappy quality pictures - phone camera is all I had at the time.

The valves did not look like they've hit anything, but it does look like they might have been sticking due to the build up causing low or no compression on the cold engine.

The chassis sat for five years until I bought it. It had about quarter of the tank when I got it. I've replaced following items: in-tank fuel lines, fuel pump, fuel filter, and of course the engine. Then, I've filled it up with good gas (Shell). Also, I've put my hand down the tank to make sure there was no solid contamination on the bottom.

I don't believe snapping my cam could have been caused by the build up you see in the pictures. Coincidence?

My plan is to take the head to the machine shop, hot tank it, pressure check, and resurface (if needed). Hopefully it's still good. Not so sure on how to prevent future build up from potentially bad gas though. Fuel cell sounds like a good option at this point to eliminate a possibility of this happening in the future.

What do you think NRR?

P.S. Photos do not give the justice to how nasty the build up really is.
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  #16  
Old 06-04-2014, 06:16 PM
Def Def is offline
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That's just a lot of PCV build-up, probably running regular oil at extended intervals and a motor that had a bit of blowby.

This is exactly why I don't run a PCV into the intake manifold, you're constantly sucking in nasty vapor under cruise with high vacuum.
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  #17  
Old 06-04-2014, 06:21 PM
Matt93SE Matt93SE is offline
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That's NOT a 500-mile motor. no way, no how.

can you see the honing marks on the cylinder walls? I can't tell much from the photo, but it looks more like 50,000 miles than 500 miles on that block.
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  #18  
Old 06-04-2014, 07:43 PM
Def Def is offline
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That head looks more like 100,000 miles and a lack of maintenance.
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  #19  
Old 06-04-2014, 08:58 PM
Rovch Rovch is offline
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Okay, okay, let me explain in more detail. The motor was rebuilt 500 miles ago. New piston rings, honed cylinder walls, new bearings, resurfaced head, new valve stem seals, and probably few more things I am forgetting. It has not gone through a single oil change since the rebuild. I was planning on changing the oil at a 1000 mile mark.

Gradually it took longer and longer to start when cold. While doing a compression check to verify the health of the engine, the intake camshaft snapped. The rest of the story is in the beginning of the thread.

I can definitely tell you that the pistons, intake side of the head, and the intake manifold did not look anything like they do right now when I've installed the engine. Just a month ago it was all nice and clean.

So this couldn't have been caused by bad gas?
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  #20  
Old 06-05-2014, 07:12 AM
Matt93SE Matt93SE is offline
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Bad gas shouldn't/wouldn't do that. sounds like you had a bad bearing or something stuck in an oil galley somewhere and that cam started locking up due to lack of lubrication.
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