Oil Pump question ( similar to other thread )

[mjkaliszak]

I have the same issue ( Oil Pump question)with the 600HO I have. The crank was changed along with a top end and during the first 500 miles I'm burning 2 quarts per 140-150 miles. Do the oil pumps fail to full flow ? I have heard that they do. How can you test or check the pump. The motor is running too fat, the plugs are black and the piston wash is too black. I have had the carbs apart and motor compartment disassembled and can't find a leaking oil line or carb problem anywhere. Messed with the jet needles and fuel screw and I can't tune the low RPM hesitation out. I find it hard to believe that I would have pilot jet problems in both carbs at the same time. With the black tar plugs and excess piston wash things don't add up. The fuel screws are good & sharp on the ends the hole does not have blockage.Any advise is helpful, I'm ready to pull my hair out.

 

[russholio]

I have heard that if they fail, they're designed to fail open (meaning they dump too much oil, rather than too little -- better to foul plugs than to melt down your engine). They are also prone to wearing so that the pump arm doesn't fully return when you let off the throttle (from what I hear on DooTalk). There is a guy on there who has develped a fix for the oil pump, he puts in a bearing that fixes the wear problem.

Here's the link to the thread: http://www.dootalk.com/forums/index.php?showtopic=165758&hl=sticking+oil+pump

 

[dab102999]

Could be, but I think more that it is just out of adjustment and letting to much oil in. If u got a service manual it shows you how to adjust it, or at least check it.

 

[mjkaliszak]

Thanks, I do have it lined up.The return spring is not sticking.
This issue is just ghosting me. I have the sled on my lift for the 4th time. On the 1st run after the rebuild it used 64 oz in 120 miles. at first I just scratched my head, then we took another road trip and ran 3 150 mile days all using 64 oz each time. This thing never used that much oil. I get 8mpg, so based on that @ 50 : 1 , I should only use 48 oz max. It seems like it empties the oil res every time out. Additionally, I didn't want ti hi-jack the other guy's thread with my ramblings.

 

[dab102999]

If u have it adjust correctly then I would say it is a bad pump. But with that said, and not saying you don't have it adjusted proper but just a fraction of an inch (like .030 off of that line) will really make a difference on oil useage. As far as mpg if you are dumping that much oil into it your mileage is going to drop so I would still use the figure of 10 miles per gallon to set it up and go from there. When u say 600 HO are we talking doo?? and what year sled is it.

 

[mjkaliszak]

It's a 600HO 2008 Pol RR. I have had 7100 miles when we blew it up and twisted the crank. It now has 7600 on it and I also concur it is the pump.Or the pump to case gasket or both. I'm getting oil leakage from somewhere but not an oil line. It seems like the pump is failing open and the base gasket may leaking also. I'm getting fresh oil dripping out of the belly/bulkhead seam but can't find a root cause. I leaks just when we run it and running " rich " . It is suddenly un-tunable and this sled used to scream. Thanks , I'm going to go after the pump & gasket ( replace them both ). This problem has really given me a headache.

 

[cih7250]

you do know there is seal in the oil pump that keeps oil from running in the crankcase and i'm not talking about the gasket were it mounts to the case, it's on the pump shaft inside the pump. hope this helps

 

[mjkaliszak]

I had varrying info on that seal. I could not find one on " online " the micro fish. Also read somewhere that the pump was not rebuildable.That is just "hear say" but it looks like the oil can get sucked into the CC when it goes bad. Thanks for the input.