Crank trueness [Archive] - Snowmobile World : Your #1 Snowmobile Forum

: Crank trueness

03-21-2002, 08:15 PM
i was wandering how do you check your crank for trueness?

03-22-2002, 03:48 PM
Download the attached file

03-22-2002, 04:25 PM
Crank Indexing download file

03-22-2002, 04:27 PM
in additon to the above file

Crankshaft Indexing (Continued)
6. *Bend the pointer or move the degree wheel until the pointer aligns with the 180 or 120' mark on the degree wheel.
7. *With the pointer aligned, make sure the degree wheel and pointer are secured and will not move out of position. Re-check accuracy of this location by repeating steps 4. and 5. . The pointer should align with the 180 or 1200 mark when the dial indicator reads. 1 00" (2.54mm) ATDC.
IMPORTANT- Do not move the degree wheel or pointer after the initial setting on the mag end cylinder - simply read the wheel and dial indicator.
Remove the dial indicator and install in cylinder #2 or center cylinder. Repeat steps 4. and 5. Note the degree wheel indication when the dial indicator reads.100"ATDC. lt should be l8O or l2Oo(:t2")from cylinder#l. Repeat procedure on PTO cylinder (#3) where applicable. Cylinder #3 should also be 120"(:i- 2") from cylinder #1.
Symptoms of an out of index crankshaft can include:
Difficulty calibrating carburetor (repetitive plug fouling on one cylinder with no other cause);
0 * *Unexplained piston failure on one cylinder (i.e. severe detonation, broken ring lands, piston holing); 0 * *Excessive vibration of engine, backfiring, etc.;
0 * *Rough idle, poor top speed.

03-23-2002, 11:28 AM
Grea stuff! *Is this available on the www? *Or a manual/book *Are fixtures available. *thanks