2015/06/17 07:37:19
Trevwood
I've pulled a so called ( by previous owner) blown motors head off and it badly oiled up in the bores and intake manifold. Like it has no rings.
It looks new inside, no lip in bores, no ware on cam lobes, clean pistons (a little black but no carbon on top) and no scratches in the bores.
My question is, why would a motor do this?
I know in older motors you run mineral type oil to bed in the rings, is it the same with these fuel injected motors?
And what grade of oil do you run in this motor?

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2015/06/17 10:57:33
Reddtarga
"So called blown motor"
More info needed. What is it's history?
 
Oiled up top end:
Could be shot oil rings, but a compression test could have shown this before the head was pulled.
 
A lot of oil in the intake manifold could indicate badly worn intake valve stem seals.
The oil is sucked out of the valve top chamber and into the intake.
Disassemble a couple of intake valves to check. Seals may be cracked and hard. Check the guides also.
 
Running in:
Overkill maybe, but I ran in my new reco 3SGE with 3 lots of Penrite running in oil (mineral)
Changed at 100kms, 700kms and then went to full synthetic after a two thousand kms.
 
Manual says use a 10W-40 oil.
2015/06/17 13:46:41
Trevwood
The story goes.........
Him and his dad (not mechanics) rebuilt the motor.
He said it was running great then it made a sound and stopped. He could see (what he called) red hot chunks on the road behind him.

Would synthetic oil get past the rings if he didn't run it in on mineral oil like you described?

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2015/06/17 15:25:23
Trevwood
Just talked to the previous owner to clear thinks up.
It was professionally recoed, head and all.
I'm thinking glazed bores.

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