The Stovebolt Site Forums The Shop Area The HiPo Shop Hydraulic Throwout bearing?

The clutch on my '47 GMC went out last week. First time driving it since early last summer, Ugh. The whole linkage setup was pretty wonky to begin with. The fork is bent and cracked so that's what ended my travels for the moment.

The truck has a small block Chevy, T5, 11 inch clutch, 621 bellhousing etc. My plan is to put a hydraulic throwout bearing in it. I'm determined to keep the original pedals, so the master cylinder for the throwout bearing will be under the floor. I'll need to fabricate a bracket for mounting. It's tight under there next to the new brake master cylinder, but not insurmountable. Here's a link to the plan from Speedway here

My main questions at the moment are (and I'm sure there will be more soon) if the master cylinder is below the throwout bearing where the bleeder is, will I be able to bleed out the system? will I need some kind of fluid reservoir, like up on the firewall? Seems like the fluid will want to flow downhill back toward the master cyl.

Here is one I bought that supposedly fits my 53 3100. I don't remember where I bought it. I'm going a different direction so I don't know if it fits. I'm a big fan of hydraulic throwout bearings. Get the ones with the bleeder hose on the outside or buy one. You don't want to bleed it anywhere near your clutch. If there is no air I don't see how it can drain down but I'm no expert. Maybe a residual valve like on brakes?

Thanks. Great pics.

There is no rule that the master cylinder (either brake or clutch) has to be mounted in the factory position. Moving one rearward gives much more room around the unit. My 37 Buick has the filler hole located under the seat cushion but since I have a lift I just check fluid level with a mirror and add fluid with a douche ball. Make the pedal to cylinder push rod stronger for the increased length.

Thanks. I spent some time under there and it looks like I can move the clutch master cylinder a few inches farther back and I'll be in good shape. I'll need to fab up a bracket but that shouldn't be a problem.