Hi Guys Blew the engine in an 03 700 edge looking for tips for rebuilding engine going to have clutch gone through and balanced and rebuilt crank w/ wide bearing what about drilling oiling holes to the pto bearing
looking for tips for rebuilding 03 700 engine
- Thread starter bigdan743
- Start date
Just passing on what I've read
The oil hole on the PTO side is easy enough to drill out. You want to drill (1/4" bit) from the divet (below the PTO piston) at about a 45* angle so the bit comes out in the same spot as the factory oil hole (the one fed by the oil line). If you come up short of the factory hole, use a grinder and slot it so oil can still get past the bearing. I would open up the factory hole toward the crank seal too, the bearings usually block most of that hole off.
Its a good idea having that clutch gone through. Balance, good bushings, and properly shimmed for belt to sheave clearance.
I would make sure that case is still putting a light crush on the bearings. I take a free crank bearing (not on a crank) and check it in each case journal, so 12 checks total (6 bearings, 2 case halves). Push the bearing into its position in just one case half, then turn the case upside down, if the bearing falls out you need to send that off to a qualified shop and have it line honed (case is NOT holding bearing properly). If the bearing is really hard to fully seat into the case and doesn't spin semi freely when pushed into position, it may have too much crush, and thereby developing excess heat. Cases need to be clean for all this, same with the bearing (clean out all oil with brake clean so it is dry, much easier to tell how hard it is crushed when its spun dry). After I check each bearing journal in just the case halves, I check each journal with a bearing in the case and both halves torqued together. It can be surprising how bound up a bearing can be when in the cases torqued down if there is too much crush. If you see this, you'll wonder how the motor ran so long.
If crush is too tight, you can use some 240grit (fine) sandpaper and take a little material off, then check crush again. Repeat as needed. Its a balance between having the case still provide enough clamping pressure (crush) on the bearing but not having too much drag in the bearing from excess crush. Polaris cases can be dead on, too tight, or too loose (or so I've read) due to lack of quality control.
Now if you have a good way to measure the case and the bearings, you have a more quantitative measure of the crank bearing/case fit, obviously more ideal.
The oil hole on the PTO side is easy enough to drill out. You want to drill (1/4" bit) from the divet (below the PTO piston) at about a 45* angle so the bit comes out in the same spot as the factory oil hole (the one fed by the oil line). If you come up short of the factory hole, use a grinder and slot it so oil can still get past the bearing. I would open up the factory hole toward the crank seal too, the bearings usually block most of that hole off.
Its a good idea having that clutch gone through. Balance, good bushings, and properly shimmed for belt to sheave clearance.
I would make sure that case is still putting a light crush on the bearings. I take a free crank bearing (not on a crank) and check it in each case journal, so 12 checks total (6 bearings, 2 case halves). Push the bearing into its position in just one case half, then turn the case upside down, if the bearing falls out you need to send that off to a qualified shop and have it line honed (case is NOT holding bearing properly). If the bearing is really hard to fully seat into the case and doesn't spin semi freely when pushed into position, it may have too much crush, and thereby developing excess heat. Cases need to be clean for all this, same with the bearing (clean out all oil with brake clean so it is dry, much easier to tell how hard it is crushed when its spun dry). After I check each bearing journal in just the case halves, I check each journal with a bearing in the case and both halves torqued together. It can be surprising how bound up a bearing can be when in the cases torqued down if there is too much crush. If you see this, you'll wonder how the motor ran so long.
If crush is too tight, you can use some 240grit (fine) sandpaper and take a little material off, then check crush again. Repeat as needed. Its a balance between having the case still provide enough clamping pressure (crush) on the bearing but not having too much drag in the bearing from excess crush. Polaris cases can be dead on, too tight, or too loose (or so I've read) due to lack of quality control.
Now if you have a good way to measure the case and the bearings, you have a more quantitative measure of the crank bearing/case fit, obviously more ideal.
engine rebilding
Thanks alot to Goinboardin, I will do those tests I own a auto repair facility in Iowa I know exactly what you're talking about. If the crush is off or the line bore is off I will get the case line bored. Thanks so much
Thanks alot to Goinboardin, I will do those tests I own a auto repair facility in Iowa I know exactly what you're talking about. If the crush is off or the line bore is off I will get the case line bored. Thanks so much
