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View Full Version : TR5/TR250 Tranny Won't go into 2nd TR250



glemon
05-05-2012, 05:13 PM
I think I am going to have to pull the transmission. The car often doesn't like going into second gear, and it seems to be happening more often.

Problem: Downshifting into 2nd often it like hitting a solid wall, on occasion upshifts too, but not nearly as often. Sometimes if works fine, up and down, on rare occassions it will go into gear with a big clunk.

I think I have ruled out hydraulic/clutch problems: I took up the slack in the linkage, no difference, it will shift in to all the other gears fine, never grinds going into reverse, I even tried going into reverse immediately after the end gear downshift block occured (after quickly coming to a complete stop of course), not problem, no grind.

If I slow down and shift into first it will shift into second after that fine. It will downshift into 2nd fine after I come to a COMPLETE stop, any rolling at all no go.

When I put a return spring on the clutch pedal it went away for a while so I thought it might be hydraulic (fluid return hole), but it came back and worse than ever.

So I really don't think it relates to the clutch or hydraulics but it someone really thinks they have a good argument or experiment will listen, don't want to pull the gearbox, but since the problem has only ever manifested itself in 2nd gear I am beginning to think that must be the issue, I rebuilt the box myself with all wear items synchronizers, bearings, bushings etc. replaced. (first time, maybe I just identified the issue!).

Marvin Gruber
05-05-2012, 07:14 PM
Will it shift into second easy when the car is sitting and not running. Sounds like shifter issue.

Marv

glemon
05-05-2012, 08:07 PM
I think I have figured the problem simple but contrary to conventional wisdom on the subject, any guesses?

glemon
05-05-2012, 10:38 PM
I didn't have time to post the answer, and I haven't had time to test thoroughly, but everything was making it worse, I was increasing the clutch release travel by futzing with the linkage.

When I first experienced the problem and through most testing I was pushing the clutch pedal down as hard as I could, seemed to make sense it the time, then I tried not pushing it down all the way, voila, problem went away, apparently you can get too much travel, don't know why it only manifested itself in second gear, maybe something to do with the direction of pressure I was putting on things or who knows?

Seems to be working great now, will futz a little more and drive a little more tommorrow, but I think I am on to something.

doughairfield
05-06-2012, 09:07 AM
Glemon,
So glad you posted this, i'm having a very similar problem on my TR4. My problem specifically is that it's getting really hard to shift into 1st or when I'm starting out, or have been sitting at the stop light for a minute. I've also been really pushing the clutch pedal down hard or pumping it in an attempt to get the selector into gear.

Like you, I've taken up all the slack in the linkage from the slave cylinder to the fork lever and gone back and bled the system again.

I have noticed it helps a little to rev the engine up a bit and then try to get it into gear, but sometimes it takes 3 or 4 tries to get into first to take off.

I'm going to try your "push the pedal in slow" trick and see if that helps. Any additional insight will be much appreciated.

TR4nut
05-06-2012, 10:34 AM
Doug-

In your case I'd be worried about the clutch fork pin not knowing anything else - or it could be a little wear on the pivot areas so you are not getting full disengagement.

Glemon's is more of a puzzler - I'm not sure why pressing more would bind 2nd. Very long shot thought, have you checked thrust washer clearance in the engine? Pushing harder would move everything forward, and potentially that would get the clutch plate to contact the pressure plate possibly. Or not, that is just a wild thought.

glemon
05-06-2012, 03:24 PM
Doug your problem sounds like a hydraulic issue to me, if it gets worse after sitting a while you may have some leakage in your master cylinder or slave cylinder bores and the fluid leaks letting the cluth partially re-engage. When the car is not rolling and you are having trouble getting into first try reverse, if it grinds something is not fully released with the clutch.

Randy, I shouldn't have a thrust washer issue, engine is recently rebuilt, I haven't checked, but that would be a lot of wear in maybe 3000-4000 miles.

Went for a longer test drive today, all shifting just as it should. I will add that one of the experiments I tried was switching from 30w non detergent engine oil in the tranny to 90W gl4 gear oil. The shifting seems about the same, if anything the synchros feel a little slower, but that is very subjective.

The tranny does shift in and particuylarly out of O/D much smoother, which is nice, it worked fine but was kind of abrupt before.

Greg

doughairfield
05-07-2012, 10:05 PM
Yes, after further investigation I also think it's a hydraulic issue. It has gotten very hard to get it into reverse as well as 1st from a dead stop. If I do about 5 quick pumps I am able to get the selector into 1st.

Both my master and slave clutch cylinders are less than 2 years old and I bled the system recently. Any suggestions on how to isolate which component is having an issue?

glemon
05-07-2012, 11:06 PM
Pull the dust caps off the end of the slave cylinder and master cylinders, look for signs of brake fluid leakage, check your fluid level as well.

Greg

TR3driver
05-08-2012, 01:25 AM
Also look at the angle between the slave pushrod and clutch lever. The lever should tilt towards the slave, so the angle is slightly more than 90 degrees. If it tilts away, then you've got a bad TOB or, more likely, a broken taper pin.

On a TR4, you should also check the adjustment of the slave pushrod. You want only a very tiny amount of slack, when you pull the rod out against the force of the return spring. The book says 1/10" but I regard that as an upper limit. 1/16" is plenty.

Basically nothing can go wrong with the TR4 slave (unless it leaks, of course). But the MC has springs and a valve inside that can malfunction. If nothing else turns up, pull it apart and look for broken springs, etc.

doughairfield
05-08-2012, 10:25 AM
Thanks guys.

I have not noticed any fluid leaking out of the slave cylinder and I was just under there 2 weeks ago to re-bleed it.

Hopefully tonight I'll have time to recheck the linkage and check that clutch lever angle.

If nothing looks amiss there, I guess I'll pull the master cylinder and check for problems there.

doughairfield
05-08-2012, 05:25 PM
I was looking at the slave cylinder today just to make sure I had not made a dumb mistake a while back when I reconnected it and noticed I put it back in the mounting bracket upside down. Meaning that the bleed nipple is lower than the hose coming from the master cylinder. Could having the bleed nipple pointing down instead of pointing up prevent me form being able to get all the air out? Thus not being to ever get all the air out?

bgbassplyr
05-08-2012, 07:43 PM
It will certainly make it much more difficult.

Kleykamp
05-09-2012, 05:50 AM
Glenn, read the thread I have going. I feel your pain. I'm now in the process...slow as it may be, of removing the transmission to inspect internal clutch parts. I believe we have settled on it being the tapered pin in the clutch fork, among other potential clutch issues. Good luck, Joe
update: got transmission out...front grease seal leaking and grease on friction plate and all over inside of bell housing. Maybe not your problem but symptoms all sound very familiar. grease causing disk to stick, throwout bearing to stick, clutch to slip and any miriad of symptoms. Hope you resolve yours without having to remove the trans.