525 EFI how many hours...
#62
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From: Johnsburg Illinois
#64
#65
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How about sludge build up? A guy at the lake has a pair of 2003 525's which he has owned since new. He has been religious about changing his oil every 10 hours or so.The boat has aprox 250 hours on it and he decided to rebuild the motors. What he found in the oilpan and pickup filters was astonishing and does not make sense. There was lots of sludge.The first 8 years , he used Merc oil and most recently, switched to a synthetic blend. What would cause this sludge situation?
#66
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From: chicago
#67
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From: Tennessee
Merc does have a TSB on the rod torque. There is a change in torque value for the rods. I think it is only due to the fact that the lube they originally used on the bolts is no longer available. That's why we use bolt stretch. It takes the torque, type of lube, accuracy of torque wrench, etc. all out of the equation. It the only way to go as far as i'm concerned.
Eddie
#68
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From: chicago
that's just ugly when that happens.
I saw a rod bust like that from an engine that was suffering from a severe case of preignition/detonation. 10:1 with iron heads and 36 degrees of lead, oh, and a mini blower making 6-7psi on pump gas. Launched the rod cap and took out the pan, block, and snapped the camshaft in two. It ran good until the rod let go.
I saw a rod bust like that from an engine that was suffering from a severe case of preignition/detonation. 10:1 with iron heads and 36 degrees of lead, oh, and a mini blower making 6-7psi on pump gas. Launched the rod cap and took out the pan, block, and snapped the camshaft in two. It ran good until the rod let go.
#69
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From: MI
Obviously, I wasn't in there when it happened, but the best I can tell, a rod bolt failed. Neither of the bolts backed out, since the pieces of bolts with the threads are still in place. Looking at the rod cap, it appears that one of the bolts failed. Once that happen, all hell broke loose. You can see that the rod cap looks like it was peeled off the rod. That would indicate that one bolt broke and the cap could no longer stay in place. Why the bolt failed.....I don't know. It's an ARP 2000 bolt, which is a pretty damn good bolt. Certainly not the best bolt out there, but more than enough for a 525.
Merc does have a TSB on the rod torque. There is a change in torque value for the rods. I think it is only due to the fact that the lube they originally used on the bolts is no longer available. That's why we use bolt stretch. It takes the torque, type of lube, accuracy of torque wrench, etc. all out of the equation. It the only way to go as far as i'm concerned.
Eddie
Merc does have a TSB on the rod torque. There is a change in torque value for the rods. I think it is only due to the fact that the lube they originally used on the bolts is no longer available. That's why we use bolt stretch. It takes the torque, type of lube, accuracy of torque wrench, etc. all out of the equation. It the only way to go as far as i'm concerned.
Eddie





