welded reverse clutches?

[wideopen231]

Ok. I take car out  last weekend.First time this year because of over blown virus crap. Car does long hard burnout,backs up fine. I stage and when I let go car moves but feels more like moped than a race car. I hit throttle shove 2nd and roll on down track.Go back to pits.Look things over.Appears  cable out of adjustment and car might have been in between low and high. Second runa bout the same excpet less go.

I get home and once I get it down only thing hurt is reverse clutch pack,By hurt I mean it is nasty black and welded together. Its not low gear band and that is 150 bucks good thing.Its not high gear clutches,probably because I have two full spare sets. I knew I should have bought spare reverse clutches.

So how the xxxx did I fry reverse?

[dusterdave173]

Maybe wrong trans brake solonoid  they make ( in general) two different travel lengths--get the wrong one travel too short and well,, you fry the reverse--I did it  I actually made a plug was footbraking and it did not hold the thing IN far enough same result

[wideopen231]

Possible ,but Doubt since it came with valvebody from FTI. Hae been told it might have had trans brake applied during run. Add in that I was screwing with delay box settings prior to second attempt.That sounds very possible.If I screwed up and set the trans brake loc out and then hit button at some point. Good thing is its not low gear band and not expensive fix.Just little time and work.

[masracingtd1167]

Chris sounds like the reverse clutch not releasing all the way ! Could the piston be hanging up in the bore ? How much clearance ? It should be about .085 ! Not sure if the linkage could cause that but you could test it on the jack stands with a pressure gauge ! Another thought did you put rubber pieces between your steels in reverse ? They don't fit very well in a powerglide case and can fall out and jam up the reverse plates !   

[wideopen231]

 I had the rubber pieces and  removed them. I will check piston clearance or should I say recheck. Had a suggestion that transbrake was applied during run. With the way the teeth are ground of fibers I am leaning towards that. Second reason leaning towards transbrake is I was resetting things in box and could have screwed up lock out and with high /low setup I could have done just that. Will still check others because jumping to what seems obvious is not always  good move.

[masracingtd1167]

I would think if the tansbrake didn't release the car would  not move at all ! I f you can't find anything wrong put a pressure gauge on the reverse port and that should tell you what's going on !

[wideopen231]

its not that it did not release its that I probably engaged it while in motion. Its high/low valve body and being able to engage trans brake in low or high and with dumb azz crew chief/driver/owner screwing with delay box and wiping out lock out I could have engaged it while in motion and had enough to wipe it out. Most of the teeth are gone off clutches and ring gear was almost impossible to remove. Luckily on real damage to ring gear,except some heat. Still going to look at others possibles.

The fact I was sitting in 90* heat waiting on some small tire crap to run 3 pairs and took 30 minutes did not help,also not excuse for stupid mistake. The crew chief is till cussing the driver and the owner is cussing us both. Man I a tiring myself out. LMAO

[masracingtd1167]

That could do it ! It's the drivers fault !

[bikeguy307]

If the brake was hit during the run it would have locked up the rear tires in low and done nothing in high (unless its a high gear leave type VB). Im leaning more towards the piston getting cocked in the case. If you are running gaskets make sure they are ok, I have seen them tear and create a "flap" the could hold some pressure in the cavitive. Make sure you have .050 to .070 clearence I lean more towards .070. Good luck with finding the issue.

[wideopen231]

That could do it ! It's the drivers fault !

Driver fault hitting button. Crew chief fault for screwing up lock out and owner fault for let us near car, xxxx I am all of them now days. LMAO

It is high/ low valve body. Agree it should lock tires up.I had a button jump out shifter once and do that about 10 feet out. Funny thing othe go=uy though I broke and I clipped him at finish line.

Like I said earlier I am about positive it was trans brake .driver screw up,but I am going to check everything else because jumping to obvious cause has bitten me in azz more times than I can count w/o removing shoes.

[wideopen231]

Waiting on new parts before reassembly and checking other possibles. Funny thing is I went to oder parts straight from FTI and with shipping cost I thought lets try jegs.Same items same price and no shipping cost. I try to support small guys first,but hey 45 bucks is lot to throw away too.

[wideopen231]

Replaced all reverse clutches .Fiber and steels. Found nothing wrong except delay box loc out screwed u\p. So looks like its all on driver.crew chief and guess also car owner this time. Wait that means its always going to be on me. LOL Oh well I built it,I tune it,I drive it and I brake it.Good thing is I am only one paying for it. LMAO . I liked it lot better when a hollower upstairs to dad and parts arrived few days later. Man I miss those days,

[Ray Hadford]

Hi   .... Food for thought. ...

We run a 225 in. front motor dragster with a trans brake glide. ... 388 supercharged small block on methanol....  1700 pound car with driver.   low 6.70 s and 203. mph are common runs on a good track.   1.01- 1.03   60 foots are also common.

A couple of years ago we discovered the number "One thousand and twenty fifth" way to loose a race. We were at Woodburn Oregon,  Pro Nostalgia drags. 

Round two, our car left the starting line normally, moved about 20 feet shuddered and leaped in the air like a frog.   At one time, it had all 4 wheels off the ground, per the announcer in the tower. 

I let up and shut down.. and we towed the car off the track.  I thought for sure we had broke a ring and pinion and it had locked up.

The  car rolled free after all that and the gears in the rear end looked ok, as viewed through a large fill plug opening in the top of the housing.   WTF...

Fortunately we have the trans brake activation voltage instrumented in our Race Pak system. We were able to look at the activation as it matched to the initial launch.  The trans brake switch had applied and released many times during the first 1/2 second of the run... my hand had already moved to the shifter lever. My thumb was not on the button.

We were able to test the transbrake /  switch button activation and found that it was right on the edge of activating and the slightest vibration would set it off, and cause multiple activations and releases.

A new , different switch design solved the issue...  That won't happen again.  We are now searching for the next SNAFU..      

Ray H. 

 

[Paul New]

I watched Rays pass it was pretty dramatic looking