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MG TD TF 1500 - Drive Shaft Bolts

In which direction were these bolts originally fitted, or doesn't it matter? On a current thread (apologies Ed) two contradictory methods have been suggested as being correct. On an earlier thread I think it was established that the general rule was that the bolt head is on the item that is being attached e.g. fender to chassis? Or was it that the head was on the part that the item is being attached TO e.g. on the chassis when fitting the radiator cross mounting rail? Maybe the fender to chassis is a poor example as there is no nut involved? I guess the drive shaft is the item that is being bolted TO the gearbox at the front & TO the diff at the rear which would mean one set would face the front & the other towards the rear. But which is which or doesn't it matter? The answer probably lies buried somewhere in the archive however it does seem relevant to raise the question here. Cheers
Peter TD 5801
P Hehir

For what its worth, the Moss picture shows bolts inserted through the driveshaft out to the trans & rear end flanges.
http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32813
JRN JIM

I have always fitted them with the nuts on the U-joint side of the flange. I also weigh the nuts and bolts to make sure they're the same weight and I use Nyloc nuts.
Kevin McLemore

Again there seem to be two approaches. So it seems either would be OK. I suspect even a barn find could have had the driveshaft removed at some point to replace the universal joints, so maybe we'll never know how they were fitted originally. Weighing the nuts & bolts is a useful comment. Clearly an imbalance is undesirable. I'm about to refit the driveshaft & haven't been able to locate the marks I made on removal all those years ago. Was there a method of marking the relationship to gearbox & diff during initial factory assembly? And how was this balance achieved? I understand how a driveshaft itself is balanced but not how it is then "balanced" to suit a particular car. Cheers
Peter TD 5801
P Hehir

Good question- I would guess factory just fitted so the halfs mated the best. I seriously doubt any trial or post assembly to the tranny/diff balance was done I recall some tack welded plates/weights that may be for balance, but those were no doubt done at shaft assembly not at installation. I think that the front and rear joints should be in the same plane (ie each joint bearing cup in straight line with same on the other end). With the small effective diameter of the bolt circle, I don't think exact bolt/nut balance matters. George
George Butz

D McKeller. Could you possibly re-post your comment & the pic from the other thread? Cheers
Peter TD 5801
P Hehir

Interesting thread in the archives
Thread: Driveshaft Observations

Mike
Mike Hart


TC did castle nuts facing center of driveshaft, at least at the rear. No washer of any kind when split pin used. Nylocks on a propshaft will unwind if the direction of rotation is right/wrong. If no hole in bolt for split pin, a split lock washer will keep the nut from unwinding much better than a nylock. If direction of rotation is such that no unwinding is going to occur, then nylocks will work for a propshaft.




D mckellar

I just came across this ad which I think I originally took from Chris Couper's website. These Philidas nuts are still on my TD's u-joints and seem to be working well. Note that the nuts are facing away from the u-joint and toward the differential.
Joe

Joe Olson

Funny thing about the ad is that with the bolts oriented that way, the direction the shaft rotates in forward gears would tend to be tightening the nuts onto the bolts constantly anyway. Looking from the rear of the car, the shaft rotates counter clockwise normally. Only if the bolts are the other way around would these locking nuts pay for themselves.
D mckellar

That sure was an interesting read Mike & I hope Fletcher & Dave are still the best of friends. :-) Nothing that clarified my question on bolt direction though. I've checked my driveshaft & can find no trace of the arrows as they've probably been painted over.

Thanks Joe. It still seems uncertain. The possibility of Nylocks unwinding if the DOR is wrong, as mentioned above, is a worry though. Maybe I should use high tensile bolts with a castellated nut & split pin & just toss a coin to determine the bolt direction? Cheers
Peter TD 5801
P Hehir

Peter

No requirement for coin tossing follow what is depicted in the image that Joe posted. This confirms what I previously advised, I assembled multiple PTO shafts on agricultural machinery during my checkered career and this was the method used mainly to conserve the attachment nuts so they were capable of being undone without having to resort to using the "hot knife".

The post in the archive raises some questions especially when you have had to have a tail shaft length converted to match a TC gearbox. I found a specialist tail shaft builder who assembled and balanced my tail shaft and it performs without fault.

The issue of balancing attachment hardware is not of consequence when you consider the flange diameters and the revs the shaft is turning at. If it was a gyro compass rotor you would apply those techniques.

If you are still uncertain find a tail shaft specialist builder and have them confirm the balance on yours. As an aside beware of where your universals are sourced from the set I bought and provided to my machinist "binned them" and fitted his own.

Graeme
G Evans

Reactivating this thread:

It appears that the head of the bolt goes towards the U joint.

Looking at parts from various suppliers, one sells regular nut and bolt, another sells nyloc nut and bolt, B&G sell nyloc nut, spring washer and bolt.

I think I am going with Grade 8 bolts. spring washer and a nyloc nut. When I win the lottery I will upgrade to Phildas nuts.

As I am swapping out the rear end during the winter I am going to order enough for both ends of the drive shaft.

Thoughts?

Peter
P G Gilvarry

While on my way home from a retirees luncheon, and going over a bridge I noticed a familiar clatter. This around the first of the month.

After, gingerly, reaching home I checked the drive Line and both U-Joints looked bad. One had noticeable play, the other had spun all the lube out and over the drive tunnel

Seems like I had taken the drive shaft out around 1984 during chassis rebuild and did not install it with the correct orientation. The arrows, which I never knew about, were 90 degrees off.

I ordered new joints from AS. I can tell you that the bolts are only able to be installed one way. I believe, with 65% certainty, the nuts are correct. But !!!

I found, upon, installation of the new u-joint that the joint cups were sliding fits in the rear driveshaft yoke. Temporary fix with Locktite. Searching the archives I am informed that the yokes are no longer available.

AS had a complete, used, assembly from a single car and I purchased that.
$120+
It had one bad u-joint but I had ordered, at the same time, two new ones, for replacement.
$19 ea +
Tom had impressed upon me the need to get the assembly balanced, so I did a search on local places that could do this. I found the following place, near me,
Drive Line Service of NJ
622 Route 46W
Clifton, NJ 07013
973-437-7900

I checked with the owner of a local repair shop who is also into racing and received a glowing recommendation.

Picked it up today
$180; Balancing and installing two U-Joints.

Now to Install it.

Posted to give you some info on my bolts/nuts and where to get your balanced.

Jim B.


JA Benjamin

Well there you go, i always thought they went the other way--Thinking the step on the flange held the head of the bolt from spinning round and the spring washer then nut came from the u/joint side
William Revit

This thread was discussed between 24/03/2016 and 26/10/2019

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