1928 WHIPPET DRIVE SHAFT

[Guest]

I have a 1928 Whippet with a lot of drive shaft vibration. The U joints have been rebuilt and the marks on the slip joint are lined up with the marks on the drive shaft. The yokes are breaking together. I think the shaft is slightly bent? I read in a 1928 Motor book that the shaft can be out several thousands as long as it is balanced. How do I balance the shaft??? I went to a local guy who specializes in drive shafts and he is afraid to touch it. HELP!!!!<BR>Larry McKeough

[Rick Hoover]

Larry,<BR>One thing is for certain, it can't be seen here on the forum, so I would head off to your nearest engine machine shop that can set up the shaft on a crank balancer and check to see if it is indeed bent. I don't understand, what good is a driveshaft specialist if he won't look at it for you? What does he do?<BR>Rick<p>[This message has been edited by Rick Hoover (edited 08-17-2000).]

[Guest]

Larry:<P>I agree with the prior comment about what good is the drive shaft guy if he won't touch it. Warning to all AACA members at this point in the message - foul, very foul language ahead. I would try a local speed shop (foul words). In fact I had a Buick where I lost a balancing weight off the shaft. took it to a speed shop (foul words again) and they took care of it right on the spot.

[Jay Wolf]

I had my shaft looked at at <BR>a Local Semi Truck place.<BR>The do shafts all the time,<BR>My was fine they didn't even charge me.<BR>My probem was the rubber mount on the Transmission had colapsed and <BR>droped the tailshaft about 1/2 inch.<P>Jay wolf<P>------------------<BR><p>[This message has been edited by elgin 16 (edited 08-18-2000).]

[ronbarn]

Bad words - bull pucky!! Speed shops are not bad. Sometimes they are the only ones that will take on some of the one-time jobs that we require. My wife's '27 Marmon engine is in a shop that specializes in race car engines. They know that her requirement is an engine that runs better than very good, but with no modifications. They have stated that they appreciate the engineering and enjoy the challenge of working on an older engine. Good source!!

[Guest]

I have to agree with the previous assessment of speed shops. Many of them these days are simply accessory dealers with expertise only relevant to the installation of fiberglass spoilers on import cars, but there are still some that are incredibly technically competent. Particularly in racing circles, these guys are forced by strict tech rules to try new things to try and stay competitive<BR>(or to cheat in new and creative ways).

[Guest]

Ronbarn & Mike: didn't mean to upset anyone with the foul language comment. But here in NJ, if you pass any of the local speed shops in my area, you can usually find a pre-war automobile that someone has started to modify and either ran out of time, money or patience. Of course by the time the car is given up on, it is hopelessly modified and will never be good for anything but parts.

[ThomasBorchers]

Larry:<BR>I know one more reason why a drive shaft can vibrate but I think this is not the reason of your vibration of the shaft but I would like to tell it here. I had this problem at a 1958 Impala. It had the same vibration like your car but an other reason: There was on one side of the driveshaft an undercoating. This was so thick that the shaft started to vibrate because it was out of balance. I removed it and: No vibration. I think your drive shaft is clean all the way, or?<P>------------------<BR>Thomas Borchers<BR>Member of AACA # 004829<BR>HCCA and MAFCA

[ronbarn]

Chris NJ - good point - there are "speed shops" that are nothing more than rodder junk makers. There are also, fortunately, some speed shops which are honest craftsmen that do help us.

[Guest]

Thanks for all the good input so far. For the record, my local guy (who I went back to) uses electronic balancing equipment and needs the correct blank for each end of the drive shaft which he does not have. He has put the shaft on a lathe and determined it was out several thousands. Because of the relatively small diameter of my shaft as compared to new shafts, they are afraid to attempt sraightening it because they have to heat it to a high temp. first. when I came home I rolled it across my kitchen table and you could see the slip joint end was wobbling. I then proceeded to try & bend the end of the shaft straight with a long pipe. I did manage to improve it but not to the point where it's good enough. Then I tried using pipe clamps as weights at various places and still no luck. I'm looking for another drive shaft at this point. I will persue local speed shops next, I'll try anything at this point, the entire car is finished and looks great but as my wife says "it's a no-go-show-boat!!"<BR>

[Guest Hal Davis (MODEL A HAL)]

Is it hollow? If not, try an industrial machine shop. They will likely have a straightening press. Machine shafts have to be straightened during the manufacturing process because of residual stresses that show up after machining the shafts, so most machine shops will have a means of doing this. This process is normally done without heating. <P>If it is hollow, they might still be able to help you, but I'd be more careful.<p>[This message has been edited by MODEL A HAL (edited 08-23-2000).]