Remove crankshaft to replace clutch?

I was listening to a Car Talk episode from earlier this year, and one of the callers had her clutch replaced, and now has a lot of noise from the engine. The diagnosis: the engine crankshaft is coming loose from its moorings. Apparently in this car, to replace the clutch you have to first remove the crankshaft.

I got to thinking, I’ve never heard of that before. What vehicle brands does this apply, where to replace the clutch you first have to remove the crankshaft from the engine? I can’t envision why that’d be necessary.

This doesn’t apply to any vehicle at all. What I suspect you heard was that to replace the clutch the engine had to be removed. It’s also possible that what you heard as a diagnosis was that the engine itself was coming loose from its moorings.

Like all fields of endeavor, the automobile repair industry is chock full of jargon. It’s very easy for someone not mechanically knowledgeable to misunderstand what’s been said. I suspect that’s what has happened here.

Without knowing the year, make, model, and mileage of the car in question it’s impossible to comment further.

The flywheel could be coming loose from crank?

Car Talk #1513, March, 2015

Deborah Bunkley (Ann Arbor, Michigan) - 1982 Toyota Corolla

Deborah had clutch work done and now her car shakes at low or high speeds. Tom and Ray suspect the mechanics who did the clutch may have done something to the drive shaft and not put it back properly. The shake is getting worse and could be dangerous-- the drive shaft could fall out, and she’d do a pole vault.

That makes sense. I lost (rubbed off) my marks on mine once and learned to make a much bigger mark after that. It’s easy to get that yoke out of balance.

A crankshaft. I couldn’t see an engineer designing an engine that the crank had to come out to change a clutch. But then I never thought I’d have to remove an intake to change spark plugs either.

Yosemite

First, one must understand the difference between a Crankshaft and a Drive Shaft.

Tester

lol … didn’t catch that one … thanks @Tester … I’m going to go back and listen to that segment of the show again, I thought they said “crankshaft” …

Toyota actually calls theirs a “propeller shaft”. Go figure.

http://www.toyotapartsoverstock.com/showAssembly.aspx?ukey_assembly=499610&ukey_make=1060&ukey_model=15430&modelYear=1982&ukey_category=21645&ukey_driveLine=6635

I’m going to go back and listen to that segment of the show again, I thought they said “crankshaft”

Just look at the transcript you posted above…

Propeller shaft goes way back as an alternative to drive shaft. I recall hearing that as a kid at the local garage. You’ll find that reference in a lot of places if’n you go looking.

I have no doubt that what you say is true. I’d bet it goes all the way back to industries powered by water wheels in the 1700s, perhaps earlier even.

Could the call have concerned a pre-1955 automobile with a torque tube. Replacing the clutch required dropping and moving the rear axle to allow room to remove the transmission. Torque tubes had a one piece pinion shaft from the transmission tail piece u-joint to the ring gear.

Ouch! The early '50s were longer ago than I thought…

Ok, I listened to that segment again. Me Culpa … lol … the Car Talk brothers never mentioned the word “crankshaft”. It was the “driveshaft” coming loose that they talked about as a possible cause. I must have developed a head gasket problem, my noggin’ sprung a 'lil leak :wink: