Visit The Dirt Forum for More Information

Author Topic:   shearing sound
modifried
Member
posted April 28, 2003 11:43 AM
Saturday heat and A feature, while accelerating i would hear and feel a shimmy. It only happened 1/2 the time. and only when i was hooked up. After the heat races i pulled my my axle to see if it was the drive flanges, but they were fine. The drive shaft was not rubbing either. I did have 10 degrees pinion angle, my pull bar backed off accidently. I think maybe it was the u joint binding. The car has a saginaw 3 speed with i mini clutch. 9 inch floater and ideas? Somthing is definitly tearing up , i wat to get it before it gets me!


modman97
Member
posted April 28, 2003 01:23 PM
Im usually the guy(driver) who breaks the stuff,Not fixes it. However, I do remember a bad pinion bearing making that nasty sound before.


jammin
Administrator
posted April 28, 2003 02:33 PM
Make sure that the motor mounts are tight and not stripped out or loose in any way, or this could cause a variety of problems from your driveshaft all the way up to your fan...could be your fan hitting something when you are on throttle. This would move more when the car was hooked up and pressure was applied to the driveshaft...

jammin

[This message has been edited by jammin (edited April 28, 2003).]

modifried
Member
posted April 28, 2003 03:11 PM
Thanks jammin, i think it is coming from the rear though. It felt like i was crossing those warning grooves on a high way just before a stop sign. The motor mounts are tight and the fan is clear. When a three speed quits, it gives at once, right? There is nothing inside it that will slip. Its either working 100percent or not at all right?


jammin
Administrator
posted April 28, 2003 03:17 PM
ring and pinion....check the spool....u-joint...(already done the drive plates).....tranny would be the next thing in line...then the clutch...thats how I would look for it.

jammin

modifried
Member
posted April 28, 2003 03:55 PM
Do you think it could have been when the rearend was transitioning (sp) from 10degrees to "in line with tranny" under power could have bound the u joint a little? I ask this because it was only at the early stage of getting hooked up.


jammin
Administrator
posted April 28, 2003 04:03 PM
Thats a possibility. How much play do you have in it at static height?

jammin

dirtbuster
Member
posted April 28, 2003 04:14 PM
We had a bad vibration last year and chased it through all the wheels, rear end and driveshaft before finding out it was a bad battery. It was creating a miss and would cause the vibration. Changed batteries and cured it. I dont recall any noise associated with it but might be something to keep in mind.


Dustejr73
Member
posted April 28, 2003 05:50 PM
Did you have a chance to try it after fixing your pull bar? If not, the pull bar being loose will let the pinion rotate too far and bind. Also, you might re-think 10 degrees. I have never had luck with more than 7 or 8.


MD
Member
posted April 29, 2003 12:34 AM
Are you running any type of limited slip dif? 10 Degrees does seem a bit high, might break a u-joint on deceleration. Under acceleration and torque a binding u-joint probably wouldn't last to long. Is your drive shaft possibly running out of throw, bottoming up against the trans? Seen alot of that with 4-links with slightly to long of shafts. Have you had anything break, replaced or worked on in the drive train recently?


modifried
Member
posted April 29, 2003 09:22 AM
I normally run 7.5 degrees. the pullbar backed off ang gave me 10deg. I did switch from a 583 to a 543 gear. so i guess it could be in the gear


MD
Member
posted April 29, 2003 03:48 PM
Good place to start looking.


KK17
Member
posted April 29, 2003 05:46 PM
The time I had this happen,it was the cluster bearings in the trans.The noise was transmitting down the driveshaft.


racer 4
Member
posted April 30, 2003 02:44 AM
Thanks for the help, I will let you know what i find.


MOD75D
Member
posted May 01, 2003 10:48 PM
Well, I adjusted pinion angle, replaced u-joint(worn very little), and checked the pinion, and tightened everything up. We are gonna race it tonight. Ill let you know what happens


MOD75D
Member
posted May 04, 2003 11:37 PM
I still have mine too. Im gonna get a shorter drive shaft, replace the clutch disks and look in the tranny. It is steadily getting worse.


MOD75D
Member
posted May 05, 2003 01:35 PM
I replaced the clutch discs and i move the rear end back 3/8" and the problem is cured.


MOD75D
Member
posted May 12, 2003 12:33 PM
Mod75d Have you replace the bushing in the back of your tranny tailstock yet?


MOD75D
Member
posted May 18, 2003 12:56 PM
mother nature won!


MOD75D
Member
posted May 19, 2003 06:14 PM
Thats to bad.