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Discussion Starter · #1 ·
Alright so my rancher 350 was rebuilt once before with no problems for the first 40 hrs then got some water in the crankcase. Changed the oil about 5 times to get the water out then it started smoking like a freight train. Bored a different cylinder installed newly bored cylinder and new piston and ring. And still smokes what did I do wrong????? Thanks in advance
 

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Residual oil in the exhaust and/or water and grime in the crankcase are gonna continue to eat your new parts till you split the case and clean it out..


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OK lets ask this
after water got into motor, did you STOP and split case to clean any possible crap that got in with the water??
if not, well, that crap is maybe eating up your new TOP end parts
your NOT the first to have this happen
and THAT is why its said, the ONLY Correct way to FIX a sunk motor, , a motor that sucked in WATER,, is to break it down split cases and CLEAN ever nook and cranny!

NOT doing so, JUST Flushing, DOESN"T remove that crap
SOME YES, get lucky and can drive for yrs, BUT as they say, FEEL LUCKY??
as NOT splitting the cases is like a lottery ticket, a gamble
I know this maybe isn't what you want to hear, but its the way it works

JUST a top end on a bottom end with crap in it, means SHORT life to the NEW top end, more times than NOT!

SO< ??

you MIGHT have excess oil in exhaust?? BUT I sadly think, you still got crap in your motor! that maybe ruined your new top end!
 

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Also, if you put a freshly bored and honed cylinder on it, without first, thoroughly scrubbing the machining grit out of that freshly machined bore... Then that fresh one is probably ruined now too.
 

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Did you clean out the oil cooler?

Did it start smoking immediately or was it a few hours of running later?

Did you replace the valve stem seals?


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Discussion Starter · #6 ·
I did not split the crank case I was told by a local race engine builder to flush the case with kerosene multiple times. I did that the first time with success till the water I found where the water came in and flushed it again and now this. It doesnt smoke when it cold but once it get hot it starts to smoke
 

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The kerosene flush is a terribly bad idea. Kerosene and water don't ever mix... And if you start the motor with anything in the crankcase other than motor oil, then you might promptly ruin it.

You can flush raw water out of the crankcase by pouring alcohol into the crankcase then draining that mixture a few times. Flush the oil cooler and oil lines as well. Repeat until you are sure you got all of the water out, but DO NOT ever start the motor while flushing it. For the final alcohol flush, mix in some motor oil with the alcohol at about a 20-1 ratio to recoat the washed bearings then drain it.

Once its empty leave the drain plug out of it, unhook the crankcase vent hose and crank your air compressor regulator down to about 3-5 lbs pressure. Then tape the trigger down on your air blower nozzle and aim it at the dipsick hole... Don't pressurize the crankcase, just ventilate it for half an hour or so.

When the alcohol is dried up in the cases you can quit it. Put the oil plug back in, hook the vent hose back up and replace your oil filter with a new one and put new motor oil in it. THEN you are ready to start the motor for the first time...

Seriously though, its best to split the cases immediately when water gets in. Then you can be sure it gets cleaned up right.

It sounds like your motor is burning off the junk thats still in it and still in the exhaust as it warms up. You DO have nothing but pure, clean motor oil in it now, dont'cha?
 

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Discussion Starter · #9 ·
Alright. Yes I put fresh oil in it after I finshed rebuilding it. Ran it long enough for it to get some heat in the cylinder then changed the oil a second time
 

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I have seen it take 2 hours to burn all the oil out the exhaust pipe -------- some thoughts of why it could be smoking = did you stager the ring gaps , did you maybe damage a ring during installation , maybe put a ring upside down or the first ring in the second ring groove , are you sure the cylinder , piston and rings are all to same specs , did you check the ring gap , is all the dirt out the crankcase and oil cooler , valve stem seals damaged during installation ------- before I took anything apart I would do a compression test , should be right at 200 psi
 
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