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Oil pump failure on 800 pro?
- Thread starter mtn_klimer
- Start date
The MTNTK kit is an excellent top end for the 800 CFI. It's too bad you are having issues. A little more info would help.
What year is the sled?
How many miles on it (total) and since turbo'd? Which kit? Was coolant level full? Thermostat ever replaced? What Fuel, ratio, oil, etc.
Could be oil related but could also be many other things IE fuel, controllers, etc. (depending on kit). There's a pretty interesting oil cap vent thread you may want to read. There's also been a couple of reports of oil pump brass gears going bad although some haven't seen it yet. Don't discount looking into the oil cap vent just because you don't have an air bubble in the oil feed line.
There's way too many other variables at this point especially when a failure occurrs 3 miles into the ride.
Can you post some pics? How do the rod bearings look? With this sled being a turbo, you may want to pull it all of the way down, especially considering it's near the end of the season.
What year is the sled?
How many miles on it (total) and since turbo'd? Which kit? Was coolant level full? Thermostat ever replaced? What Fuel, ratio, oil, etc.
Could be oil related but could also be many other things IE fuel, controllers, etc. (depending on kit). There's a pretty interesting oil cap vent thread you may want to read. There's also been a couple of reports of oil pump brass gears going bad although some haven't seen it yet. Don't discount looking into the oil cap vent just because you don't have an air bubble in the oil feed line.
There's way too many other variables at this point especially when a failure occurrs 3 miles into the ride.
Can you post some pics? How do the rod bearings look? With this sled being a turbo, you may want to pull it all of the way down, especially considering it's near the end of the season.
Agreed.. usually not a good idea to hold a 2 stroke at mid speed/load for extended periods of time..
Oil pump failure
Sorry, Long story to follow, but maybe it will help someone?
What year is your sled?
I had the exact same thing happen to my 2011 Pro Rmk 800!!
Put a piston “Fix” kit in at the beginning of this season with around 1200 miles on the sled just to give me peace of mind!
Here’s the story. Bear with me!
When I originally pulled the engine apart, there were some fairly deep gouges in the PTO piston and cylinder with some light dings in the head! Humm what the heck did this come from? Fueling looks good!
Brushed it off as something musta gotten in there from the factory when new as it still ran good, the rod bearings and crank bearings all rotated smoothly! Nothing obvious!
OK, so I replaced the cylinder (Extra $$) as well as installing the “Fix” kit, also turned up the Oil pump 3 turns! Got’er all fixed up for the long haul!!!
Well after approx. 400 miles the sled started sputtering at about 5000 – 5300 rpm (slow putting speeds)
Seemed real rich? Did the TPS adjustment, replaced the injectors, fuel filter and no change. Aw Ha! It’s the Reeds! Tore into it to replace them. Pulled out the PTO reed cage thinking there’s a broken reed and no, they looked fine? The Mag side too! Well crap! What the heck?? Took a look at the PTO piston skirt and it’s all messed up! The Mag side piston had some slight scuffing but nothing bad.
OK, so I repeat the “Replace Pistons and Cylinder” again! I installed the new reeds anyway!
I did notice that even with turning the oil pump up, it didn’t seem to use any more oil than it previously did? I came to the conclusion it was I just a bad piston! Bad luck for me!!!
Ok, Got'er all fixed up again then another 200 +- miles it locks up again!! Gerrrr!! Same thing, PTO piston!
WTF I’ve replaced a lot of pistons and such over the years and I’m beginning to think I’m all FU@KED up here!! What the Hell is causing this.
Got back to reading everything I could find about the situation and what could be causing it!
Got onto the Oil Cap “Not Venting” threads. Well this was an Aw Ha moment! Crap could something so simple cost me so much???
OK again!! Sorry!
Replaced every thing again drilled holes in the underside of the oil cap and thought this is it! Got’er Fixed!! Gona watch the oil tank real close and see that’s it dropping!
Buy the way, forgot to add. I put a lot of oil in the gas tank each time for piston break-in.
Anyway, 50 miles into a great spring ride and WTF! WTF! WTF! Sh@t, DAM. Ya know what I’m talkin bout!!!
Same thing but this time I hear a loud squeal before the motor comes to an abrupt stop? I initially think it’s just a blown belt? But NOoooo It’s the motor again!
Tear it down and find the crank is locked up!
The PTO bearing is completely dry with a little dirty greasy look to it! Apparently the bearing has been coming apart all this time sending pieces of the race up through the PTO piston taking it out.
It hasn’t been getting oil at all and the cylinder has been lacking oil as well.
It’s weird! I’ve rotated the crank every time I replaced the pistons and all seemed to be smooth?
Something’s gone wrong in the pump as it wasn’t producing enough pressure to push the check valves open. The Mag side seemed to look like it was getting oil. At least enough to keep it from seizing up!
I checked to see that the check valves were working properly and they seem to be! I attached an airline with an adjustable pressure regulator. They all seem to open about 5psi!
After all this I really can’t tell you how to check the oil pump while it’s on the machine. The only way is to watch the oil tank level as you ride for the day but it’s probably gona be too late if it doesn’t drop unless you catch it early!! It just seems to use less and less each ride??
I did take the pump off and attach a drill motor, hooked up the oil tank and ran it. Holding the lever in the wide open position I could see the oil pulsing very slowly up the PTO bearing oil line.
I don’t know how fast the oil should move? The pump does need to create enough pressure to push past the check valves. So to confirm if the pump is good or not. Seems like a bench test that checks for pressure at each oil line outlet would be required? I have a 3013 oil pump on order.
And an FYI: The 2011 Pro RMK Oil Pump Part Number has been updated on the OEM parts Fitch if that’s any indicator they may be a problem with the earlier Oil Pumps!!
Sorry, Long story to follow, but maybe it will help someone?
What year is your sled?
I had the exact same thing happen to my 2011 Pro Rmk 800!!
Put a piston “Fix” kit in at the beginning of this season with around 1200 miles on the sled just to give me peace of mind!
Here’s the story. Bear with me!
When I originally pulled the engine apart, there were some fairly deep gouges in the PTO piston and cylinder with some light dings in the head! Humm what the heck did this come from? Fueling looks good!
Brushed it off as something musta gotten in there from the factory when new as it still ran good, the rod bearings and crank bearings all rotated smoothly! Nothing obvious!
OK, so I replaced the cylinder (Extra $$) as well as installing the “Fix” kit, also turned up the Oil pump 3 turns! Got’er all fixed up for the long haul!!!
Well after approx. 400 miles the sled started sputtering at about 5000 – 5300 rpm (slow putting speeds)
Seemed real rich? Did the TPS adjustment, replaced the injectors, fuel filter and no change. Aw Ha! It’s the Reeds! Tore into it to replace them. Pulled out the PTO reed cage thinking there’s a broken reed and no, they looked fine? The Mag side too! Well crap! What the heck?? Took a look at the PTO piston skirt and it’s all messed up! The Mag side piston had some slight scuffing but nothing bad.
OK, so I repeat the “Replace Pistons and Cylinder” again! I installed the new reeds anyway!
I did notice that even with turning the oil pump up, it didn’t seem to use any more oil than it previously did? I came to the conclusion it was I just a bad piston! Bad luck for me!!!
Ok, Got'er all fixed up again then another 200 +- miles it locks up again!! Gerrrr!! Same thing, PTO piston!
WTF I’ve replaced a lot of pistons and such over the years and I’m beginning to think I’m all FU@KED up here!! What the Hell is causing this.
Got back to reading everything I could find about the situation and what could be causing it!
Got onto the Oil Cap “Not Venting” threads. Well this was an Aw Ha moment! Crap could something so simple cost me so much???
OK again!! Sorry!
Replaced every thing again drilled holes in the underside of the oil cap and thought this is it! Got’er Fixed!! Gona watch the oil tank real close and see that’s it dropping!
Buy the way, forgot to add. I put a lot of oil in the gas tank each time for piston break-in.
Anyway, 50 miles into a great spring ride and WTF! WTF! WTF! Sh@t, DAM. Ya know what I’m talkin bout!!!
Same thing but this time I hear a loud squeal before the motor comes to an abrupt stop? I initially think it’s just a blown belt? But NOoooo It’s the motor again!
Tear it down and find the crank is locked up!
The PTO bearing is completely dry with a little dirty greasy look to it! Apparently the bearing has been coming apart all this time sending pieces of the race up through the PTO piston taking it out.
It hasn’t been getting oil at all and the cylinder has been lacking oil as well.
It’s weird! I’ve rotated the crank every time I replaced the pistons and all seemed to be smooth?
Something’s gone wrong in the pump as it wasn’t producing enough pressure to push the check valves open. The Mag side seemed to look like it was getting oil. At least enough to keep it from seizing up!
I checked to see that the check valves were working properly and they seem to be! I attached an airline with an adjustable pressure regulator. They all seem to open about 5psi!
After all this I really can’t tell you how to check the oil pump while it’s on the machine. The only way is to watch the oil tank level as you ride for the day but it’s probably gona be too late if it doesn’t drop unless you catch it early!! It just seems to use less and less each ride??
I did take the pump off and attach a drill motor, hooked up the oil tank and ran it. Holding the lever in the wide open position I could see the oil pulsing very slowly up the PTO bearing oil line.
I don’t know how fast the oil should move? The pump does need to create enough pressure to push past the check valves. So to confirm if the pump is good or not. Seems like a bench test that checks for pressure at each oil line outlet would be required? I have a 3013 oil pump on order.
And an FYI: The 2011 Pro RMK Oil Pump Part Number has been updated on the OEM parts Fitch if that’s any indicator they may be a problem with the earlier Oil Pumps!!
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the last side is of the PTo side starting to show wear marks
WOW! It does look light they were lacking on oil!
From the picture, it looks like the piston is dry!
Does the crank look like it has a good oil film on it?
From the picture, it looks like the piston is dry!
Does the crank look like it has a good oil film on it?
Looks identical to what ive seen before on 100% certifiable siezes due to lack of or no oil. The worst being right where the injector rinses off the piston I believe.
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