FX691V oil consumption

LawnWizard

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Please forgive me if this is a stupid or redundant post. I have replaced a couple of FX850V engines because they eventually used so much oil. This FX691 is really just starting to get bad. (It has 1375 hrs) My question: is it possible to re-ring this engine by just removing the heads and bottom engine case (without removing the internals)? I have no reason to believe they is anything wrong that new rings and and a light cyl hone wouldn't fix. Any advice will be greatly appreciated.
 

StarTech

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Are you sure it is not just bad valve stem seals? I just did late last year Kawasaki v-twin with 3000+ hrs and the only thing I found was a badly worn oil pump and bad valve stem seals. The seals were the source of excessive oil usage.

When it comes to doing rings you need to spec out the cylinder to make sure that it hasn't ovaled and/or tapered. IF either then OS is necessary.
 

txmowman

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You cannot re-ring without removing the pistons from the cylinder. No offense but if you don’t know this, you probably don’t want to attempt on your own.
 

LawnWizard

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In a word, no. I'm not sure it's not just valve stem seals. I did have a bent exhaust pushrod about 400 hours ago. Would that give any indication of valve (or seal) issues?
 

LawnWizard

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You cannot re-ring without removing the pistons from the cylinder. No offense but if you don’t know this, you probably don’t want to attempt on your own.
I'm aware that the pistons need to come out. I was referring to the crank and cam shafts. Specifically, is there room to remove / replace and properly torque the rod cap bolts.
 

StarTech

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Well like Txmowman said things have to come apart. You can't even try to remove the crankshaft without taking the rod loose. Kinda sounds like you have no experience even working on an engine at all.

But yes the rod screws and caps has to come off while the crankshaft is still in place.

Bent push rod usually indicates a valve guide migration problem which bust the seal as the spring caps bottom out on the seals and the guides.
 

txmowman

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I'm aware that the pistons need to come out. I was referring to the crank and cam shafts. Specifically, is there room to remove / replace and properly torque the rod cap bolts.
Sometimes, you can unbolt the rod and pull it back enough to remove the wrist pin and then push the piston up the cylinder and out the top. I might only do this if I was replacing a piston on one cylinder only. If I am doing both, I would also remove the crankshaft.
 

StarTech

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Sometimes, you can unbolt the rod and pull it back enough to remove the wrist pin and then push the piston up the cylinder and out the top. I might only do this if I was replacing a piston on one cylinder only. If I am doing both, I would also remove the crankshaft.
Curious. How the heck are you installing the piston(s) from the inside the crankcase? I have always removed and installed them from the head side here. The only I install from crankcase side is on hand held two cycles.

I suggest the OP get a copy of the service manual and read it over before attempting anything.
 

LawnWizard

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Well like Txmowman said things have to come apart. You can't even try to remove the crankshaft without taking the rod loose. Kinda sounds like you have no experience even working on an engine at all.

But yes the rod screws and caps has to come off while the crankshaft is still in place.

Bent push rod usually indicates a valve guide migration problem which bust the seal as the spring caps bottom out on the seals and the guides.
Did you even read my post?
 
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