Tranny/Clutch Overheating...is this possible??? Need some help guys...

Silver95GSX · 12-13-2007, 05:38 PM

Alright guys bear with me here...I am going to explain the problem to the best of my ability so you can understand what is going on and then any helpful tips would be nice.....Alright so heres the problem....when I cold start the car up, everything is fine, the clutch releases where it should and things are good....now the problem comes in right here when I was driving on the turnpike in 90 degree weather to chicago...When I am crusing at a normal speed between 40-70 the car is fine...now I hit bad stop and go traffic and I noticed after about 5 min of sitting in traffic the clutch release point started releasing at higher and higher points as the car just pretty much sat there at idle heating up...it eventually got to the point where the clutch wouldnt release...I could let my foot all the way off the clutch and have it in gear and the car wouldnt stall..it still acted like it was in gear and had the clutch depressed... the car wouldnt move, it would just rev and rev and wouldnt release so I got it to the side of the road and turned the car off but let the fan run and popped the hood to let it try and cool off a bit...after about 10-15 min of that I turned the car back on and the clutch was normal again, releasing just like normal....so basicly as long as im at a crusing speed and keeping the air moving through the clutch is fine, but the second that I hit city stop and go traffic it does the same thing...It almost seems to me like its heat related, that something is overheating and causing the clutch release point to change the hotter the engine bay gets and then eventually to the point where it wont release and im stuck not being able to move...hopefully you can get a good idea of what I just explained, if not then ask me to clarify something....also the car has a new sheptranny and ACT2600 with only about 1500 miles on both, but nevertheless the car still did this before I put the new tranny and clutch in so i dont know, is there maybe a trannsmission cooler or something I should try??? shoot me some ideas, thanks...

1LE · 12-16-2007, 07:05 PM

Boy is this a familiar problem... One of the TolDSM guys (now down in Rossford) had the same issue. We never found the exact problem, but eventually the trans broke while he was shifting it while hot (when it wouldn't disengage properly). Dropped in a new trans. Unfortunately, I can't say if that fixed it though, broke an axle on the first test drive and it's been sitting for around 3 years now without being put back together. However, in the short test drive, the main problem did not happen, but not sure if it got warm enough though...

Way back originally, one thing we noticed was that if it got hot enough, the hydraulic fluid for the clutch system would start boiling. Does yours do that? Once the fluid started boiling, the clutch pedal would start sticking to the floor. Has that happened to you?

Our prime suspects were either the clutch itself, or one (or both) of the hydraulic cylinders...

tenn-gsx · 12-16-2007, 07:29 PM

This sounds alot like pedal pump up. Try adjusting your clutch push rod in just a little. Make sure you have 1/2-1 inch free play in your pedal before you start feeling pressure from the clutch.

Silver95GSX · 12-16-2007, 11:38 PM

I never noticed if the clutch fluid ever stop boiling and no it never wanted to stick to the floor...its the complete opposite, it becomes harder to depress it, you can feel it get stiffer and stiffer....I just dont understand this at all and to what is causing this and how it seems there is no fix for it.....

DSMopar · 12-17-2007, 05:03 AM

Well it's pretty obvious it's the hydraulic system. I'm not too familiar with the hydraulic clutch pedals on these cars, but is there a flex line in the system? If so I'd bet it's expanding when it gets hot and acts like a one way valve...

Silver95GSX · 12-17-2007, 02:53 PM

Yes in fact it does have a short section that is just a flexible rubber type tubing and it sits just above the tranny....the rest of the line is then a hard line...now they do make Stainless steel replacement lines for the flexible section....you think if I replace it that maybe that would solve my problem??

DSMopar · 12-17-2007, 06:46 PM

i'd say it's a stong possibility, if it's not that then possibly the MC...

1LE · 12-17-2007, 08:56 PM

Quote:

Originally Posted by Silver95GSX

Yes in fact it does have a short section that is just a flexible rubber type tubing and it sits just above the tranny....the rest of the line is then a hard line...now they do make Stainless steel replacement lines for the flexible section....you think if I replace it that maybe that would solve my problem??

I don't think I've ever seen one that still had the ol' rubber line!

I thought they had all been switched to stainless by now!

I do seem to recall that, way back in the day, the guys with the rubber lines had some sort of heat related issue, when used with anything stronger than a stock clutch. However, I'm old and my memory is frequently faulty... Anyone remember for sure?

Defiant · 12-18-2007, 02:27 AM

The clutch won't transfer its heat to the clutch hydraulics. Your clutch pushrod is blocking the fluid return port, and needs to be adjusted.

There is no heat problem with your system.

Silver95GSX · 12-18-2007, 03:03 PM

So your confident that its because it needs adjusted and that a SS line wouldnt fix the problem

DSMopar · 12-19-2007, 03:43 PM

well just to clarify I wasn't suggesting his tranny was transfering heat into the lines, just that it was the rubber line possibly expanding. This happens on the rear brake flex line on old cars (the one that almost no one replaces) and the line expands. The pressure from applying the brakes is enough to overcome the restriction but it doesn't allow the fluid to release and thus sticking brakes. Same thing COULD happen to a DSM if there's a rubber line in the system, but it sounds like the pedal mis-adjusted is a more likely occurance (never heard of it but i'm new to these cars).

Defiant · 12-20-2007, 05:52 AM

A clutch throwout isn't withstanding anywhere near the pressure a brake system is: you'll not be able to expand a reinforced line with it.

Silver95GSX · 12-28-2007, 02:57 PM

well im really hoping that this is it then....but if its not...do you have any other suggestions??

Elvenhome21 · 12-28-2007, 06:43 PM

first off bleed the system, or save some hassles later and get a slave rebuild kit.

DSMopar · 12-29-2007, 06:37 AM

Quote:

Originally Posted by Defiant

A clutch throwout isn't withstanding anywhere near the pressure a brake system is: you'll not be able to expand a reinforced line with it.

well I already agreed it's probably the clutch rod like you said, but wanna bet about that pressure statement? It's not normally at brake pressure, but the MC bore size is the same and your foots the same, so you CAN apply near the same pressure...

Defiant · 12-30-2007, 12:24 AM

Think so? Is the clutch system vacuum-assisted? Is it operating as many slaves?

Chalk and cheese.

Silver95GSX · 03-05-2008, 03:32 PM

so if I need to adjust so there is more freeplay at the top...which way should I turn the rod...In or out?

Defiant · 03-06-2008, 01:19 AM

Good god, it's March. You haven't fixed this thing since DECEMBER?
http://www.dsmtuners.com/forums/driv...roper-way.html

Morphius · 03-07-2008, 11:24 AM

Quote:

Originally Posted by DSMopar

It's not normally at brake pressure, but the MC bore size is the same and your foots the same, so you CAN apply near the same pressure...

No, you can't. Pressure in a brake system is much higher. You've overlooked the reactive force provided by the calipers bottoming on the rotors. It provides a "stop" for the system. The clutch system just reacts and the PP fingers move out of the way. Nothing is stopping it at the end of the pedal stroke.