This page is geared towards the use of a GM starter shim kit. But, similar problems
arise with all brand starters.
Replacement starters from the auto industry often end up in boats and in some instances,
they just don't work or fit properly. (Not to mention the risk of explosion)
In cases other than GM starters of this type often the cause and solution entail replacing
the starter and or flywheel with a "matched" set intended for unit in the first
place. Starters that come in from the rear and are mounted to the bell housing and not
directly to the block, (Inboard applications) are more likely to end up with a mismatch,
if not careful.
Look at your old starter. Then compare it to the pictures below. Notice how the teeth are
worn in different areas and different ways. Explanations of causes and solutions are
Note: Although problems are similar, no
matter which brand motor... These solutions are for GM starters mounted to the block,
only. Other brands could use similar solutions, but be careful.
BAD ONES LOOK LIKE THIS,
Problem: Starter too far from flywheel.
Solution: Check for correct model starter. If OK, Install shim on outside pad, only.
(This puts the starter closer to the flywheel..., think about it.)
Problem: Damaged Flywheel.
Solution: Check for correct model starter. If OK, Replace flywheel. Check shimming.
Problem: Loose mounting bolts
Solution: Torque bolts properly during installation.
Problem: Engaging starter with engine running.
Solution: Don t engage starter with engine running.
Problem: Starter too close to flywheel.
Solution: Check for correct model starter. If OK, Install shim across both mounting bolts.
1) Place starter in position and finger tighten the mounting bolts beginning with the top
bolt (the top bolt must be mounted first to avoid breakage of this "ear")
2) Check the flywheel's ring gear clearance by inserting the "1/8" gauge tool
between the armature shaft and a tooth of the ring gear.
Note: An 1/8" piece of bar stock or
1/8" diameter steel pin can be used as an adhock tool if the GM one is not available.
( It has to be precise to measure correctly, we're not talking a lot of slop here.)
3) If the gauge tool cannot be inserted (fits too tight) use the entire shim or shims
across both holes. This moves the starter down and out, Away from the flywheel.
Refer to figure 3.
4) Remove shim or shims if the shim tool is loose between the shaft and tooth.
5) If no shims have been used and the fit of the 1/8" gauge tool is too loose, add
half shims to the outside pad, only, until the proper fit is obtained. This moves the
starter in and Toward the flywheel. Refer to figure 1.