The Ford Barn

rotorwrench · 12-20-2017, 11:44 AM

An interference fit is dependent on the overall diameter of the fitting parts. It starts at around .0015" per inch at 1-inch diameter but then starts to decrease per inch the larger the diameter gets. I would say that it would need to be around the .015" figure give or take. The larger the diameter the more it expands when heated. An eighth of an inch is way too much. The flywheel, starter, and bell housing will have to work with each other.

If you heat it much hotter than 300 degrees, whatever temper in the teeth will suffer. If you heat it blue and it still won't go on then that is telling. I'd say you have the wrong flywheel for the application or you have the wrong starter ring.

12-20-2017, 11:44 AM	#22
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 18,010	Re: Y block flywheel ring gear An interference fit is dependent on the overall diameter of the fitting parts. It starts at around .0015" per inch at 1-inch diameter but then starts to decrease per inch the larger the diameter gets. I would say that it would need to be around the .015" figure give or take. The larger the diameter the more it expands when heated. An eighth of an inch is way too much. The flywheel, starter, and bell housing will have to work with each other. If you heat it much hotter than 300 degrees, whatever temper in the teeth will suffer. If you heat it blue and it still won't go on then that is telling. I'd say you have the wrong flywheel for the application or you have the wrong starter ring.