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Author Topic:   New to Sprints
rdwind
Dirt Roller

Total posts: 7
posted July 28, 2003 10:57 PM  
I am new to sprint cars. I bought my first sprint car this summer. I put a new engine in it and when I was push starting it all of the bolts holding the torque tube to the quick change rear end pulled the helicoils out. The bolt holes in the rear end were loose or striped out so I put heli coils in to fix this problem. Any ides what I could have had wrong to cause it to pull all off the bolts out? I had squared the rear end.

mod4
Dirt Freak

Total posts: 223
posted July 28, 2003 11:52 PM  
I could be wrong, but when the rears take a good wreck that also happens - is it possible it was previously damaged ?

KSGerry
Dirt Freak

Total posts: 376
posted July 29, 2003 08:17 AM  
I would also suspect that the threads in the rear-end were damaged beforehand. Perhaps from overtightening as the torque bolts are very hard. However there are other possibilities to cause this condition. Check for any sort of bind at the torque ball. When the car is on it's wheels and again when the frame is jacked up simulating the full travel of the rear-end try to rotate the torque ball. It should spin free. Also check for adequate travel between the two halves of the torque tube, the proper length of the driveshaft and 10-10 coupler. Make sure the front of the drive shaft is not bottoming out in the front splined yoke. Also check all driveline components for trueness...the front coupler and U-joint, the torque tube, the driveshaft and 10-10 coupler, even the face of the rear-end where the torque tube bolts to the rear-end. Saftey-wire the roll pins in the coupler to keep them from backing out. Keep the U-joint and driveshaft splines greased.

Another cause is the rear-end chatter when starting a sprint car but there is not much you can do to avoid that problem. The midget guys have a valve to lock out the front brakes. When pushing off, they keep their foot on the brake...sliding the rear wheels until up to speed. Then they release the brake allowing the rear wheels to instantly turn the engine and fire the car once oil pressure is up. Then the brake valve is switched to it's normal position.

Good luck and have fun. Stay safe!
Gerry

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KSGerry

[This message has been edited by KSGerry (edited July 29, 2003).]

iowa_dirt_track_girl
Dirt Freak

Total posts: 461
posted August 06, 2003 04:10 PM  
where are you racing sprints at?

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you never know how fast you are driving, until you blow the announcers hat off!!!

goinrcn44h
Dirt Freak

Total posts: 205
posted August 07, 2003 01:31 AM  
Well,
I have done the exact same thing the last 2 nights. well sorta, it not only ripped the torque tube loose it also pulled the lower input shaft out and snapped it as well. As a way to fire the car and break in the motor I had the input shaft spudded and welded so I could fire the car. well it initially fired but then ripped it loose again.
So far I have only one theory, that input shaft must have taken damage when I grenaded the motor last time, last night it just finished it, tonight, the welding on the shaft must have either crystaled the hardness or taken all the hardness completely out. either way, and this is after much thought, nothing in front of the tube can tear it out, so it must be coming from behind, take the rear end apart, and if you find something concrete, let me know..
44H

Sprinter 53
Dirt Newbie

Total posts: 2
posted August 11, 2003 05:12 PM  
If you are convienent to the Dallas area, Kim Wilke is the guy to contact about fixing your rearend. The problems you are having are not normal. I would suspect that one of the shafts inside was bent or something. Anyway, Kim can fix just about any rearend that is worth repairing. Email me if you need his phone number.

goinrcn44h
Dirt Freak

Total posts: 205
posted August 12, 2003 02:18 AM  
Boy oh boy,
I must admit several things none of which are easy or cheap, but possibly may someday help someone else out so here goes.
I put a new input shaft in the rear end and new seals, everything else looked like brand new, put it all back in and attempted to fire at the track on fri. morning. Guess what... it pulled the torque tube off again, and then the rear end rotated down and bent the driveline.... OK, now I am ****ed, I start pullin stuff apart, and a guy that was helpin me out wanted to verify that I wasnt out 180 on timing, etc. so we are pullin wires and he asks me which wires are which, I knew I had one on that side that wasnt marked but he then asks well, ok, but why are they numbered on the wrong side? gettin my drift? I had odd side on even and vise versa, dumb, dumb, dumb. I looked straight at them like 20 times and it just never clicked. sooooo, I get a new driveline cut to length, redo the tube again... and low and behold it fired right up, sounded awesome, I even nailed the timing spot on. Now the downside... in the last hot lap session it decided that the u-joint had gone through enough abuse and went boom like a grenade, took the bellhousing and ball as well, somehow the tube and shaft were still straight, just impacted with mudd. So, another hard lesson learned, I did rebuild it the best I could, started dead last in the D main, transfered out of that to the C, started 16th in the C and went clear to 4th, packed the right rear with mud, came in , cleaned it out went back out, and rallied back to 6th.... 1 spot away from transfering to the B.... sorta, I guess they said I was a lap down when I went to the paywindow, but they had me prep my car and get ready for the B as first alternate.... it dont matter now anyway, I didnt transfer so I didnt care, but the bonus was the motor didnt blow up, and actually this thing is smokin fast, way better than what I had, and everytime it gets fired, it feeld better. so no bent corners and motor is still intact, it was a win regardless..
44H

rdwind
Dirt Roller

Total posts: 7
posted August 13, 2003 12:01 AM  
[QUOTE]Originally posted by rdwind:
Thanks for all the help. Sorry it took so long to get back to post a reply. It turned out that the holes that I had helicoiled had been pulled enough that there wasn't enough material left to hold the helicoils in. I repair the next set of holes and they seem to be holding so far.
My next problem is that I installed the magneto and all i could get it to do was back fire through the headers and carb. I checked to make sure that I had it in right, which it was and all the engine would do was backfire. I installed an HEI ignition system {it about killed me to put a battery in a sprint car} and the runs fine. Any suggestions on what could be wrong with the magneto, or possible my installation of it?


goinrcn44h
Dirt Freak

Total posts: 205
posted August 14, 2003 12:23 AM  
what kind of mag is it? and is it an internal coil or an external coil type? when you say backfire, that could need further explanation, also, with any mag, they should NEVER! be spun unless they are either grounded to a block or to themselves, they put out so much juice they will actually burn themselves out. and when you install the mag, you need to be coming up on #1 in the fire stroke and then rotate the mag back one tooth so when you slide it in, it lines up with one in the cap, also you need to be at your timing mark as you put the mag into place. maybe somethin in there helps hopefully
44H
oh, and make sure all the wires are on the correct sides......

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