Thread: Rebuilding 99 XP 951
03-30-2010, 07:24 PM #1
- Join Date
- May 2007
Rebuilding 99 XP 951
Is there a how-to somewhere out there? I'm having trouble removing the exhaust bolts. My allen sockets can't fit in most of the places. The allen key itself is too big and where it does fit it doesnt provide enough leverage. My Clymer's manual doesn't help much either.
Another problem is that it oil fouls brand new plugs after about 30 seconds of running. Then it bogs and cuts in and out. Compression was 120 in both cylinders but I was told it should run fine just low power. What is the compression supposed to be at?
03-30-2010, 08:17 PM #2
get a set of the "BALL" end allen sets,you can gett'm at Autozone
03-30-2010, 08:18 PM #3
120 is fine for a new engine...mine was about there also. as for the exhaust bolts they are a pain at first but when you take it off 10 times you learn the tricks. you will have to cut down a short allen key on the short side and use a box end wrench. slide the allen key through the box end to get leverage on the longer side.
03-30-2010, 09:14 PM #4
A '99+ 951 should pretty much never foul spark plugs.
Is the oil pump indexed properly? That is, if it is still injected.
If pre-mix, what ratio are you mixing it?
The ball end hex socket or key (extra long works best on all but the one next to the MPEM) is the way to go along with a modifed wrench for the nut under the pipe. There is a special wrench sold for it but some of our more, well, frugal brothers have made thier own .
04-01-2010, 08:24 PM #5
04-03-2010, 04:03 PM #6
- Join Date
- May 2007
Thanks for the help I didn't think about cutting the hex keys down or sliding a wrench over them.
04-04-2010, 08:06 AM #7
The oil pump is on the front of the engine. If you still have the big plastic air box you will need to remove the front snorkle, front air intake tubes, get a mirror-on-a-stick and a good flashlight.
You can see the two injector lines where they come up over the top of the Mag cover. With the mirror and light follow them down until you see the oil pump. The oil pump has a lever on it that is attached to the throttle cable. This allows for the pump to meter the amount of oil going into the engine.
There is a mark on the lever that should line up with a mark on the body of the pump at idle. The adjustment is in the cable. There is a plastic thing (can not think what to call it) with a jam nut that adjusts the length of the cable. Loosen the jam nut and turn the thingy unil the two marks line up. Then put the jam nut back and that is it.
If you have the pipe off this is a lot easier.
On the '99+ throttle cables the oil pump index does not change when the idle is adjusted at the carbs (it did on the older models and the pump had to be re-set after every carb idle adjustment).
If the oil pump cable is broken or was left off the pump will default to its wide open setting (a safety feature). At high RPM this would probably not be a problem. At idle and such it could maybe cause it to foul the plugs.
Also, if the oil pump cable was not installed correctly you will get this. The lever must be rotated back against the spring before the cable is installed. If this is not done, the pump will run wide open.
If you are removing the pipe be sure to check out this thread:
If you do not have a belt sander some 80 grit paper on a flat block of wood works quite well.
I also suggest you replace the pipe mount bushings even if your's look ok. An ounce of prevention, as they say, and worn out bushings and improper installation kill more 951s than anything else, IMO.
04-04-2010, 08:17 AM #8
I just removed the bolts on my 2001 RXDI and used a cut down allen wrench just like Jim here on the site said! WORKED GREAT, just have to take small turns and take your time. Did you soak down the bolts with PB Blaster? I did a few days before I started and the bolts came out easily once I broke them loose
04-04-2010, 08:24 AM #9
Make sure and get ALL of that penetrating oil out of the threads before you put the pipe back on as you do not want it to interfere with the loctite when you put the pipe back on.
04-04-2010, 08:29 AM #10
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