Sierra 18-5910 Starter Motor, New
- Brand:
- Sierra
- Part no:
- 18-5910
Where to buy
View on Amazonpaid link
Sierra 18-5910 is a new starter motor for small block V6 and V8 engines with a 14-1/4 inch flywheel and a bottom mount. It has an offset bolt pattern. It is listed as a replacement for Mercruiser 50-12177A2 and 50-99418A2, and for OMC 984456 and 986505. Check your flywheel size and bolt pattern against those details before fitting it.
Our take
The 14-1/4 inch flywheel and bottom mount in the fitment note are the first things to check on this Sierra starter, along with its offset bolt pattern. It is listed as replacing Mercruiser 50-12177A2 and 50-99418A2, so those numbers on your old motor are a quick confirmation.