New TKX Transmission wont go into reverse with engine running

[Rebostar]

Greeting folks. I took the Roadster out for its first test drive today. I had to turn off the engine to get it in reverse.
I put a new Tremec TKX in my MK IV. I have the clutch adjusted correctly. Clutch is fully released about 2/3 peddle. There is just a scosh of cable free play at the quadrant. 1st through 5th no issues. Shifts normally.
Problem: With the clutch peddle bottomed out, (almost to the front wall) I feel and hear the reverse gears not meshing. With the engine off it goes into reverse just fine. Depress the clutch, and it starts right up, does not creep, starts to move when the clutch peddle is 1/3 released normaly. It just will not go into reverse with the engine running.
I'm very familiar with the Top Loader. Never seen this before. This is the first Tremec I've ever owned. I bought it New from Summit. I thought I'd re-adjust the clutch cable to get the maximum release possible to see if that makes a differance in the morning.
Has anyone ever seen this? Any suggestions?

Other than the reverse issue it drove and shifted great. Steering was a bit touchy but I'll get the castor and camber adjusted per spec before the next drive. Its about 3' short of where in needs to be on the castor. That should help the twichyness. (is that a word?)

Please feel free to make any suggestions about the reverse issue.

[Windsor]

Likely the clutch not releasing all the way.

Not grabbing enough to move the car, not loose enough to let you put it in gear.

(ETA) I'm not sure on the TKX, does it have a synchro for reverse?

Either way, try pulling it into second right before you put it in reverse to stop the front of the transmission from spinning, see if that helps.

If not, check out the clutch.

[Jeff Kleiner]

Every time I’ve encountered clash or difficulty going into (the non-synchronized) reverse it’s been because the clutch was still dragging enough to turn the input shaft. Yes , I know that you know how to adjust a clutch but just saying… Try this; at a stop with the clutch disengaged put it in a forward gear—-this will stop the input—-and with the clutch still fully depressed move it QUICKLY into reverse. If it goes without protest it tells you that the clutch is dragging and spinning the input.

Jeff

EDIT:Sounds like Rob was saying the same while I was typing!

[Rebostar]

Every time I’ve encountered clash or difficulty going into (the non-synchronized) reverse it’s been because the clutch was still dragging enough to turn the input shaft. Yes , I know that you know how to adjust a clutch but just saying… Try this; at a stop with the clutch disengaged put it in a forward gear—-this will stop the input—-and with the clutch still fully depressed move it QUICKLY into reverse. If it goes without protest it tells you that the clutch is dragging and spinning the input.

Jeff

EDIT:Sounds like Rob was saying the same while I was typing!

Jeff & Rob
Thanks for the quick reply. I'll get on this first thing in the morning and let you know what the results are.

[BUDFIVE]

Rebostar,
When I rough adjusted my cable clutch (McLeod Super Street Pro) after I first put the engine/TKX in I couldn’t get the clutch to release.. Short version, I was OVER driving the clutch, past the release point. Once I adjusted for LESS travel it released. Maybe the same for you?

Long version. I had a 3’ lever on a hub with the TKX in gear and it wouldn’t turn with the clutch to the floor. I adjusted the clutch and floored the pedal with the fork hitting the front of the bell housing cutout and no release. The fingers were flat as viewed through into bell housing. McLeod tech support told me I was probably driving the fingers past the release point which is before they are flat. He suggested having a friend hang on the lever while I slowly push the clutch in. When the clutch hit about halfway, the hub spun. Now I’ve adjusted with the engine running and tires off the ground. This is good cause you can see if the synchros spin the tires when you shift into first and reverse with the clutch in. It takes a lot less pedal than I thought to release these McLeod clutches.

[Nigel Allen]

A slightly heavier weight trans oil may assist. Put a few more miles on the clutch to bed it to the flywheel.

[Mike.Bray]

I had the exact same thing, the clutch wasn't fully releasing. Probably has to do with reverse not being synchronized.

[Rebostar]

Many thanks to Ron and Jeff K. for their input last night on the clutch/reverse issue. This morning I put the car on the lift. Sure enough I adjusted the cable 1/4" more and now it goes into reverse easily with the engine running. First I tried the quick shift from 2nd to reverse with the engine running and sure enough it went in like butter. Upon initial set up I adjusted the clutch peddle so when the peddle was depressed about 2/3, I could spin the rear tire with my hand with ease. I should have taken it up just a bit more. It was just on the edge. That last 1/4" of adjustment freed the clutch up.

I'm gonna call this a "VGO"... that is "Valuable Growth Oppertunity"! They are usually much more painfull than this!
Thanks everyone for the input
Allyn

[Windsor]

Good to hear.

All's well that ends well.

[SourceLee]

I haven’t the slightest clue why the following works but it works for me. I depress the clutch, put the tranny into 1st gear and then into reverse. During the entire sequence I have the clutch engaged. I read about this on a hot rod forum. Strange but it works. Maybe a transmission guru can chime in. Doesn’t apply to this situation but If the clutch linkage isn’t the issue maybe this will help. This isn’t a solution but it may get you out of your driveway.

[rich grsc]

No, you have the clutch disengaged. The why has already be talked about, and he has already "fixed" the issue

[SourceLee]

No, you have the clutch disengaged. The why has already be talked about, and he has already "fixed" the issue

Meant to include that it may not apply to this situation but may work if you’re in a bind.

[BrewCityCobra]

This has been a very helpful conversation. My TKX has been difficult to shift into reverse during Go-carting as well. Didn't realize there was no synchros on the reverse gear.

Will need to check my clutch.

[Mike.Bray]

This has been a very helpful conversation. My TKX has been difficult to shift into reverse during Go-carting as well. Didn't realize there was no synchros on the reverse gear.

Will need to check my clutch.

Mine was fine until I put the floormats in. That extra layer under the clutch pedal did me in.

[lewma]

Every time I use reverse I first select second, then it goes into reverse without any issue at all. Its second nature now.

[cv2065]

Every time I use reverse I first select second, then it goes into reverse without any issue at all. Its second nature now.

I do the same.

[dstelter]

Every time I use reverse I first select second, then it goes into reverse without any issue at all. Its second nature now.

yep I'll be the third on this. second then reverse. work every time.

[Windsor]

I haven’t the slightest clue why the following works but it works for me. I depress the clutch, put the tranny into 1st gear and then into reverse. During the entire sequence I have the clutch engaged. I read about this on a hot rod forum. Strange but it works. Maybe a transmission guru can chime in. Doesn’t apply to this situation but If the clutch linkage isn’t the issue maybe this will help. This isn’t a solution but it may get you out of your driveway.

The theory is that the input shaft of the transmission is turning* and it's easier to use one of the forward gear synchros to stop it than to deal with the gear grind of going into reverse (when reverse has no synchro).

* With the clutch depressed and the shifter in neutral, the "front half" of your gearbox is "free to turn as it desires." The pilot bearing has some influence, the should-be-completely-engaged clutch may have some influence. If you stomped the clutch and shoved the shifter into neutral while rolling, angular momentum could be in play. Individually each of these shouldn't make the input shaft turn.

shouldn't. :)


yep I'll be the third on this. second then reverse. work every time.

Me too!

[nashuanuke]

just had this happen, and I knew I saw this post recently, went out and checked and sure enough, slides right in from 5th