Chief Bill
Need to replace the oil pump on my 17kw Generac 992 engine. Have the stator separated from the crank cover, however can't separate the rotor from the end of the crank. Does anyone have a solution. Have tried everything I ca think of. HELP!

ChiefBill    
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78buckshot
The factory recommended procedure is to cut the original rotor bolt, take about 1.25" off the hex end, then slot the end of the remaining bolt in order to turn it with a screwdriver. Thread it into the crankshaft then thread a metric bolt into the end of the rotor to push against the long bolt, the rotor will pop off. OR - use a rubber mallet to gently work back and forth at the end of the rotor shaft.
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MacL
Have you verified there is no discharge from the pump?  This not a common problem to lose an oil pump.

To verify a discharge, you can remove the oil filter and put a pan underneath the flange and with the gas turned off to prevent starting, crank it for a few seconds.  If oil comes out the pump is fine.
State your problem, not your diagnosis.
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Chief Bill
78buckshot.  Thanks for the advice. What I did today to get the rotor off, was to thread a 12mm bolt through a chain and had two friends use the chain to bump the chain while I used a bar on the edge of the coupled end of the shaft at the crank case while working together it took two tries to get it off. The only problem after that was to get the chewed up plastic gear off. Every thing worked out in the end and the generator is back in service.  Thanks again for the reply.
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78buckshot
Do you have specs for the torque values on fasteners, rotor and stator bolts are much lighter than you would otherwise think.
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Chief Bill
No, I do not. Would be handy to have for future though!
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78buckshot
Ziller can recommend the correct diagnostic manual for you machine if you call them with your serial number. Good all-around info including torque specs for external fasteners. Keep your fingers crossed - trashed oil pump is an indication of underlying engine problems.
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Chief Bill
Thanks for the information. Oil pump seems to be a common problem in Generac units. When I was scanning the internet for a replacement pump everyone I contacted was temporarily out of stock, including Generac. I had to wait over a week to get one. I would think that a bronze or brass gear would make more sense.  
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Geoff Z
We have never had an oil pump fail to our knowledge. Certainly not with our local customers. We've never carried one in stock or sold one. I don't think we can call it a common problem. Others can weigh in on their experience.
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Peddler
I have never replaced one since 1999.  I did replace a governor on a unit that was from the yearly 2000's which had striped the teeth off the gear but it was not one that we sold or serviced and it appeared to have lacked service.  My conclusion at the time was that the unit had gotten into a long run with old oil and the oil had caramelized and the gear simply stuck to the shaft and the then stripped on a later start up.  Who knows but it isn't a common problem for sure.   
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restosud
Chief Bill wrote:
No, I do not. Would be handy to have for future though!


rotor bolt is 30 ft/lb
stator bolts are 72-84 in/lb or about 6 ft/lb
engine adaptor is 25 ft/lb
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Chief Bill
Thanks for that information. It will be very useful on future repairs.
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