Transbrake only works when car not running

Old 12-09-2020, 08:19 PM
Junior Member
Thread Starter
Join Date: Dec 2020
Location: Mooresville, NC
Posts: 2
Unhappy Transbrake only works when car not running

Hi all! Newbie here with my first question. I have a TH400 with a BTE pro transbrake. New build by a professional for drag racing. He is unavailable for a week or two and I am trying to figure out this issue. Has been run at the strip a total of 4 times since install. Worked sporadically each time so thought there might be a loose connection somewhere and on first time using reverse for more than 5 seconds, it fried the power wire. Since then, rewired it and still sporadic. What I mean is it works one minute then won't the next. Odd thing is when the car is off, hit the button and you hear it click every time no problem. I can see it and watch the plunger with the hood open looking down past the headers (external solenoid) and can test it using a new switch I wired in that is not mounted yet. Coil cord will just reach outside the passenger side so I can press the button while looking. Previously was wired through the button on the shifter. Thought that was the problem but does the same thing with the new switch. When the car is started, nothing, solenoid cycles less than half the time. Cut the car off and works just fine. It is not run through any other electronics. Car is 69 Nova with a 383, Weiand 142 blower, Holley Sniper EFI 1250. Fuel pump and EFI are on separate stand alone switches wired to battery +. Ignition switch (keyed column factory switch) powers accessories like gauges and tach. Also starter wired through factory key switch to start. Since the TB is also wired direct to battery + it shouldn't make any difference running or not from an electronics standpoint. I tried with all switches and ignition on to see if it made a difference and it does not. Cycles every time until you actually start the engine, then it is hit or miss, works one time, then won't the next. Now it is more often not working than working. Moved the ground wire from the trans case to frame as the BTE website says it is not a good idea to ground to the case. Recommends grounding to frame or body. Made no difference on this issue though.

Thinking maybe there is an internal pressure problem?? But if that was the case it seems that it would be the same when at idle and would either work or not work, but would be consistent one way or the other, not sporadic. If I increase rpm's it doesn't make any difference either. Any ideas?? Could it be when the hot wire fried and melted it shorted the solenoid, just enough to make it weak but not completely? Maybe that's why it works when engine is off and no fluid pressure? Then once running the solenoid is not strong enough to move the piston when there is pressure?

Appreciate any and all comments as I am knew at working with a transbrake, this is my first.

Forgot this, if I hit the button and then start it, it works until I release the button and have to use it again. In other words I can't get reverse unless I hit the button before starting, hold it, start it, and then shift to reverse while holding the button. Once I let go it releases and won't work again. Can't very well do that when staging though, lol!

Last edited by PapaWatts45; 12-09-2020 at 08:24 PM. Reason: Additional information
PapaWatts45 is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -