The Ford Barn

matchlessman · 12-26-2021, 03:06 PM

Is there a technical reason the crank gear that drives the cam gear has to be so tight on the crank? I got mine off using an impact gun on a beefy puller. I'm about to put the new one and it's equally tight. I've worked on plenty of engines over the years and never experienced a crank gear being so tight. Is there a technical reason for the tightness? I can't think of one.

Ken
Eastern Ontario

nkaminar · 12-26-2021, 03:56 PM

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The crankshaft vibrates in torsion. The nose of the crankshaft vibrates more than the rest of the crankshaft. If the gear and pulley are not tight on the crankshaft they will fret and wear. Modern engines have vibration dampeners on the front of the crankshaft that dampens out a lot of the vibration. They need to be tight too. You can buy a vibration dampener for a Model A engine but stock engines don't need one as much as engines that rev higher.

12-26-2021, 03:06 PM	#1
matchlessman Junior Member Join Date: Jul 2021 Location: Eastern Ontario, Canada Posts: 11	Tight crank gear Is there a technical reason the crank gear that drives the cam gear has to be so tight on the crank? I got mine off using an impact gun on a beefy puller. I'm about to put the new one and it's equally tight. I've worked on plenty of engines over the years and never experienced a crank gear being so tight. Is there a technical reason for the tightness? I can't think of one. Ken Eastern Ontario

12-26-2021, 03:56 PM	#2
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 3,897	Re: Tight crank gear Sponsored Links (Register now to hide all advertisements) The crankshaft vibrates in torsion. The nose of the crankshaft vibrates more than the rest of the crankshaft. If the gear and pulley are not tight on the crankshaft they will fret and wear. Modern engines have vibration dampeners on the front of the crankshaft that dampens out a lot of the vibration. They need to be tight too. You can buy a vibration dampener for a Model A engine but stock engines don't need one as much as engines that rev higher. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.