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MG MGB GT V8 Factory Originals Technical - help with htob!

I have a 2.8l v6 with a t5 5 speed(NWC) and a howes racing htob. I have the engine and tranny in the car but When I attepmted to turn the crank with the tranny in nuetral the crank will only move slightly. if I depress the clutch the crank will then turn. The spark plugs are removed and this engine has has not run since the crankshaft was R&Red due to a spun bearing. Have I put to much shimming behind the htob? I did the measurements as the instructions say and had to use 2 shims? If the htob is shimmined to far foward would it cuase this? or is this normal? Maybe someone can explain. I am begining to disassemble to remove the engine again but maybe you can tell me something before i get to far.
andy heston

"if I depress the clutch the crank will then turn" Sure sounds like that is the problem. I hope for your sake that someone will disagree with me, I know it's a lot of work to pull the engine to set the HTOB up again. Good luck.


If there are too many shims, the clutch will simply not engage fully--but it shouldn't prevent the engine from turning. Sounds to me like the trans isn't really in neutral.

Wayne Pearson

I went out to the car with the transmission in gear and spun the rear wheels and the engine does not turn but the wheels turn freely. I can feel at the shifter the tranny moving thru gears but I guess that does niot mean anything.

andy heston

Andy, Have you changed your e-mail? I've been unable to get thru with the one listed on this site.
John Davis

yes I have. I have attempted to change it here but it never goes through. I emailed you. it is from my work but i included mt home address.
andy heston

Your symptoms sound conflicting. Let’s imagine what would happen in a car known to work correctly…

If up on jack stands the wheels should turn freely if the transmission is in neutral and an detectible increase in resistance if the clutch pedal were depressed. You would feel increased resistance if the transmission were in gear and there were no motor and with a motor it should be near impossible in gear because you would be hand turning the motor unless the clutch pedal was pressed.

Now if the wheels turn freely and the motor doesn’t that means
1. The transmission is in neutral or
2. The clutch is disengaged because the pedal is pressed or
3. The clutch is disengaged because the HTOB is too far forward or
4. The transmission has a problem.

Back to the first problem…

If you had a motor in the car without a transmission the motor you should be able to turn the motor over with a ratchet or breaker bar and you would feel a fair amount of resistance. With a properly working drive train and the car up on jack stands you should feel no difference hand turning the motor if the transmission is in neutral. With the transmission in gear there would barely any additional resistance with the pedal pressed. In gear without the pedal pressed you would now also be hand turning the transmission, driveshaft and wheels. The additional mass should make it very difficult, but I imagine it should still be possible unless the hand brake is set.

Now with your car on jack stands you can hand crank the motor with the clutch pedal pressed, but you can’t hand crank the motor if the clutch is not pressed. This is what I would expect if the transmission were in gear and the hand break set. In this case it sounds like the clutch is functioning properly, but…
1. The transmission is in gear and/or the hand brake is set or
2. The transmission has a problem.

In one scenario the transmission is in neutral and the other it is in gear, which is not logical unless you changed it. In both scenarios there is something wrong with the transmission.

It looks like you’re going to have to wrestle that transmission out of there and hand turn the input shaft as you shift the gears to see that the output shaft behaves as expected.
George Champion

Andy, just need some clarification to your update post. Did the driveshaft turn when you turned the rear wheels, and are you saying that it feels like you are shifting to all the gears rather than feeling the gears turn (through the shifter) while turning the rear wheels?

Is it possible that the top of the trans has been removed and the shift forks didn't go back properly or are bent or ...?

Wayne Pearson

Thanks for the help. I have found the problem! It was the htob, but it was the stud that you place on the tranny to hold the htob in place that was causing the issue. The stud was in too deep. it was in the way of some gearing inside the tranny. I backed it out and the tranny shaft spins. drive it in further and it won't. I placed a spacer on it and solved the issue. now i have to figure how to finagel that tranny back on. I left the engine in.

thanks again
andy heston

This thread was discussed between 16/10/2002 and 17/10/2002

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