onebad636

iTrader: (13)

Sometimes when you shift gears it feels like the clutch is still engaged. So when you take it out of gear you feel the car surge. Also when under hard acceleration it is hard to get it in the next gear. It does fine at low rom's.

Any input is appreciated

itsslow98

iTrader: (18)

Sounds like a clutch or hydraulic issue to me. If you put it in 6th gear and floor it do the RPMs rise?

onebad636

iTrader: (13)

Just normal. The clutch does not slip at all, feels like it doesn't disengage all the way

punishmentcycle

iTrader: (6)

Stock clutch? If youve installed a clutch at anytime, did you measure the slave air gap? Id start there if its hanging up

onebad636

iTrader: (13)

It has a monster clutch in it that was in it when I bought it. I had a new motor built for it and it has done it since then. Not sure about before that.

odthetruth

iTrader: (4)

Do this.

Throw car in first gear.
Keep clutch pedal all the way down
Rev to 6k

Does car lurch\move?

NIKDSC5

iTrader: (10)

This, but do it on a lift or jack stands so you are not high RPM slipping the problem.

You will see the tires creep forward under 1k rpm if it is dragging.

Also, like already said....sounds like you need the master cylinder up grade.

mackdaddy66

I would first check and make sure the mast cyl resivoir for the clutch is full and then bleed the system just in case they didn't do a good enough job when they put the new engine in. doesn't make sense that it worked good before the new engine and now it is screwed up unless there is air in the system or they didn't shim your clutch right when they went back together... the upgrade kit is something that would be a good idea to do, but I haven't done it yet and still have no issues.. I am going to switch to powerglide or otherwise I would do it though

onebad636

iTrader: (13)

Any recommendations on where to get a new master cylinder if it turns out I need one?

mackdaddy66

I have read on here that tic performance or McLeod sells them.... another thing it could be but I doubt that it is, that the pilot bearing is bound up on the input shaft... happens sometimes when things aren't quite lined up right and you are in a hurry and pull it home with the bolts... hope it is not that though... then tranny has to come back out

hefftone

PMC (philistine master cylinder) is a tilton unit modified for our cars, about $380. Sound like disengagement....get on jack stands, see if wheels turn with clutch depressed (in fear engine running). Might need shim under the slave...

wes8398

iTrader: (2)

Me's thinks that if there isn't TOO much extra gap to compensate for, the PMC could eliminate the need for a slave shim. If the OE hydraulics are lacking, the extra volume that the PMC pushes will move the slave piston more, thus disengaging the clutch more effectively. No?

bmylez

iTrader: (3)

Yes, the PMC is all about maximizing stroke length/pressure.

onebad636

iTrader: (13)

It is full of fluids. I am sure it is not disengaging because if it is in gear, you push in the clutch and rev it up past 5k you can feel the car surge.

bmylez

iTrader: (3)

Well, I'd get a PMC asap, then.

heavymetals

iTrader: (3)

No where did I read where you say you bled the system.

Do you have a remote bleeder?

onebad636

iTrader: (13)

I have not bled it yet but will attempt to before I buy a new mc. The bleeder is under the car next to the trans so that should be a blast

wes8398

iTrader: (2)

Work from easy/cheap fixes to the bigger stuff, man. You definitely need to give this thing a proper bleed before anything else. And by proper, I mean it's going to take you an hour or so to get as much air out of that system as possible. A Motive bleeder or something along those lines would help you a lot. Otherwise you're going to need a helper and you'll be doing a lot of pedal pumping and cracking/closing of the bleeder screw. Too bad you didn't install a remote bleeder line when you did the clutch; but if you do wind up dropping the trans again I'd suggest you invest the $40 and install one then.

If a good bleed doesn't get things right, THEN start looking into the PMC (which would be a good investment anyway), dropping the trans, and all that kind of stuff. If you do any reading on the topic around here you'll quickly learn that an un-bled (or improperly bled) hydraulic system on these things can cause some pretty severe symptoms. Luckily, it's a pretty simple and cheap fix much of the time!

ls1247

iTrader: (2)

From what I'm reading in the post linked below, the PMC won't make up for clutch/flywheel shimming issues but the extra volume created by it will give the slave cylinder the hydraulic force it needs to fully disengage the pressure plate.

see post 18....https://ls1tech.com/forums/cadillac-...ve-spacer.html

wes8398

iTrader: (2)

Do you mean slave shimming issues? If so, I disagree. Even if the gap (as measured in my post above) is excessive, I think the PMC could help with the OP's issues (at least to some extent). The situation would have to be such that the OEM master doesn't extend the slave piston to it's maximum throw when the clutch pedal is pushed to the floor. In other words, if you push the clutch pedal to the floor (max out the master's displacement) and it only has the "power" to extend the slave piston 75% of it's throw; then the new master should improve on that due to it being able to push more volume. Improving the slave's throw would hopefully improve the clutch's disengagement. Even if the gap is excessive (to a point).