acadian
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- Joined
- Mar 5, 2010
- Messages
- 1,379
Quick background:
1) Top end rebuild last season, including new barrels, head rebuild (new seats a'la Gord Bush), new KPMI guide blocks, and new cam followers (timed R radius)
2) Motor ran very nicely but quickly developed a low oil pressure problem once warmed
3) checked all the usual suspects, cleared oil lines, replaced oil pump (backup Morgo pump installed to be sure), new crank feed oil seal, new OPRV, scavenge pipe cleared in TS case, pressure checked to EX followers and crank
No joy, problem persisted. Discovered metal swarf on magnetic drain plugs, and since it only appears once warmed up I assumed a big end issue.
Fast forward:
1) cases split this weekend, took rods off expecting to discover a mess
2) crank journal look pristine, I mean no scoring, I set my MIC to 1.6235 and wouldn't clear the journal, set to 1.6240 and it's a tight sliding fit across the journals. I will plastiguage to confirm, but the journals are not the issue
3) just popped out sludge plug, the trap is clean, and I mean CLEAN, no gunge buildup (I've run with a spin on filter for 10 years now)
So, I'm at a loss right now.
Only things I can think of:
1) the tappets installed are actually not timed (though they measure up as such)
2) I somehow fubared installing the EX tappet block, though I don't see how, everything lined up (I'm dense, but not that dense)
3) cracked crank????
4) oil leak past sludge plug?
5) oil leak at tappet feed spigot in barrels (no oil leaked externally, but maybe dumping inside the case?)
Any tips welcomed, thanks for readings
1) Top end rebuild last season, including new barrels, head rebuild (new seats a'la Gord Bush), new KPMI guide blocks, and new cam followers (timed R radius)
2) Motor ran very nicely but quickly developed a low oil pressure problem once warmed
3) checked all the usual suspects, cleared oil lines, replaced oil pump (backup Morgo pump installed to be sure), new crank feed oil seal, new OPRV, scavenge pipe cleared in TS case, pressure checked to EX followers and crank
No joy, problem persisted. Discovered metal swarf on magnetic drain plugs, and since it only appears once warmed up I assumed a big end issue.
Fast forward:
1) cases split this weekend, took rods off expecting to discover a mess
2) crank journal look pristine, I mean no scoring, I set my MIC to 1.6235 and wouldn't clear the journal, set to 1.6240 and it's a tight sliding fit across the journals. I will plastiguage to confirm, but the journals are not the issue
3) just popped out sludge plug, the trap is clean, and I mean CLEAN, no gunge buildup (I've run with a spin on filter for 10 years now)
So, I'm at a loss right now.
Only things I can think of:
1) the tappets installed are actually not timed (though they measure up as such)
2) I somehow fubared installing the EX tappet block, though I don't see how, everything lined up (I'm dense, but not that dense)
3) cracked crank????
4) oil leak past sludge plug?
5) oil leak at tappet feed spigot in barrels (no oil leaked externally, but maybe dumping inside the case?)
Any tips welcomed, thanks for readings
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