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MG TD TF 1500 - My propeller shaft is in a 'death grip' ...help!
|In all the years I have been taking cars apart, never had this happen....|
The rear flange of the tranny is in a "death grip" with the front flange of the propeller shaft....
The shaft at the axle end is loose, (all bolts are out, of course), and the two front flanges refuse to separate.
In the photo, I have put 50/50 solution of power-steering fluid and acetone, on the meeting faces, and I have a jack putting pressure on the joint...But something tells me this won't be enough to break it loose....(see photo)
I tried tapping around the perimeter of the shaft flange, with a BFH, but I didn't want to damage the flange.....
What next?...Thanks in advance.
|Are there flange "fixing" bolt at the top and bottom of your picture? |
If so insert a a bar in the gap left between the U joints and the movable flange, Insert threaded bolts in the threaded portion of the flange arranged to bear on the bar.
This is the opposite of the way they normally go.
Slowly and uniformly tighten then, tapping all the time so they push the joints apart.
I might help to c-sink the bar and put points on the bolts so they dont slip.
This may or may not damage the U joint.
If the holes are not top and bottom you might try two bars horizontal and 4 bolts.
Same caution above slowly, uniform and taping.
Depending on how much force it may or may not damage the bearing races.
|As I remember there is a raised portion on the flange that fits into a recess on the transmission flange |
(unless I am mixing up my cars) and you usually have to push the front drive shaft yoke section back on the adjustable spline portion of the drive shaft. Yours looks slightly different in this area? - you may have to undo the flange at the rear axle pinion and drop it, and the pull the entire drive shaft to the rear.
As mentioned in the start of the thread, all bolts are out of the flanges, on both ends...My flange is not threaded, but have nut and bolt fasteners....
there is a raised portion on the axle end of the shaft, (also what appears to be a nut), but the WSM, shows no such raised portion on the tranny end....
It is beginning to appear that I may have to loosen the rear axle, and move it rearward, to get enough clearence to drop the rear-end of the shaft, which is loose, but will not come clear of the axle flange.
Thanks for the input...Please keep the suggestions coming.
|They say when in doubt get a bigger hammer, but I like a blow torch. Heat should get these apart.|
I am sure if you are able to separate the two flanges even slightly the shaft will drop. Do you think you might sacrifice something like a wood chisle to try and tap between the flanges? Also do you think it might be possible to remove two of the caps on the u-joint so as to move the shaft out of the way? You would then be able to insert a long rod in the two flange holes and let leverage do its thing. Both ideas may be goofy but other than that if it were mine I probably would have used a bigger hammer by now. I am not vert patient:)
|Edward - In you picture, the front yoke is pressed all the way back on the splines until it is pressing against the drive shaft itself. Undo the rear axle and slide it back a bit and the flanges should come right apart. Once you get it loose, find out why there is no free space for the front yoke to slide back and forth - the end of it should rest at least an inch from the drive shaft. Cheers - Dave|
|You could possibly gain some room by jacking up the rear using the chassis not the rear axle. The Axle will drop a bit, extend the driveshaft and allow room for it to come off.|
It might work
|A J Clapham|
|Take a cold chisel and your BFH and give it a sharp blow at the flange joints. Keep your feet out of the way.|
|Fire wrench! Mike|
|I'm sure you will get it apart, but I'm curious as to why the spline has no free play. Could the shaft possibly, originally, come from another car? Interesting. PJ|
|Is the back end off and free? If it is, the spline position doesn't matter. If not, the main piece is jammed foreward and it wont' come off due to the inner lip. LaVerne's method should work if it is free. George|
|Edward, The reason your flanges will not separate is because someone prevoiusly used a hammer on the end of the transmission flange distorting the recessed edge and then when the two flanges where bolted together they have become locked and swaged tight. You will have to use a cold chisel between the two flange joints as LaVerne suggested to pry them apart. Cheers Phil|
|I doubt you need a cold chisel. Take off the u-joint and slide a metal rod in the flanges and apply a slide hammer. There is a recess, and it is locked up. If you wreck the flange, one from any MG since the TC, including Sprite, midget, MGA, MGB, MGC should fit.|
When you go to reassemble them, carefully dress out the imperfections with a file.
You might be able to break the splines loose after the Prop shaft is off by pumping in grease.
|Thanks all for the suggestions....|
I did not know there was a recess at the front end flanges....
I also noticed no free-play in the shaft, which leads me to believe that either the axle is too far forward on the springs, or the engine is too far back on the mounts, or a combination of the two...
Since I am re-building the rear springs and links, anyway, I'm going to go ahead and loosen the rear axle, and move it back, to get the rear flange clear of the axle.
I'm not crazy about the idea of removing the U-joint bearings, but will hold that as a last resort.
I have already tried the cold chisel, with no success....
There is no space whatsoever, between the two flanges.
I'm thinking that playing a propane torch on the tranny-side of the flange, will allow it to expand enough to break free....
I'm glad I haven't driven the car on rough roads with the shaft in this compressed condition!
|Sorry Edward. I was under the impression that the rear end was completely loose. Now I get the impression that it's tight also. Can we see a full shot of the drive line? I know that the spring perches for the axle location are not centered but if I remember correctly the short length goes towards the the engine. If I am wrong then that would account for the no play condition in the drive shaft. Possibility that the drive shaft has been modified so a measure of the length would be in order. I have one on the bench we could compare to. Also I'm not sure if Rocky has had a rear end conversion and if the pinion flange may have been extended for some reason so a shot there along with a measurement might be in order. No beating with the BFH if it's all snugged up tight. You will just make a lot of noise and get nowhere fast.|
|O.K. guys....Success!....Here's what I did.|
First, the rear flange was already loose, with about a 1/4" gap...
But, based on all of your comments, I loosened the rear axle, and moved it just enough to allow the rear flange to drop....
This, by the way , had absolutely no effect on the front flange.
Please note that the flange had soaked overnight in a mixture of acetone and power-steering fluid, my favorite bolt loosener....
Anyway, since I felt I had nothing to loose, I took my largest two-leg screw-style puller, and clamped it to the outer perimeter of the shaft flange, without touching the tranny flange...
I then whacked the side of the puller, toward the rear of the car, as hard as I dared with my BFH.
This caused a tiny opening between the two flanges....
I then took a large screwdriver, and hammered it into the small opening, causing the two to separate.
I did notice that the oil had soaked into the small indent in the flange, so I think it helped a lot....
I also found a very small bump, in the inner perimeter of the tranny flange , that was probably the cause of the tight fit....Images follow. Look closely at the bottom back hole, and you can see the damage. (sorry for the slight blurr)...Also notice the lack of a cotter pin in the crown bolt!
Thanks for all the help.
|Here's another shot of the prop shaft laying loose.|
I will measure the compressed length of my shaft tomorrow.
If you would post your measurement, that will be a big help.
Please measure to the center of the fixed portion of the U-Joints, as keeping the flanges from flopping will be almost impossible.
Incidentally, the in-out movement of my shaft is about an inch, so I'm going to be moving my axle back 1/2", giving the same movement in either direction....
|"Incidentally, the in-out movement of my shaft is about an inch"|
Who out there is going to be the first to comment?!!
Well, you just did!
|Jasper L Nederhoed|
|Oh yes!! Well spotted Jasper|
|In this case you will definitely have to move your rear end! :-)|
in photo #1 the prop shaft seems to be at a steep angle as if the axle is hanging without the restraining straps.If this is the case this will cause the axle to move forward as it moves down making the sliding joint bottom out.With the straps in place there should be 3/16" free movement in the sliding joint.
Not sure what you mean, but the prop shaft is off the axle and is just laying there....
The axle, at this point, is loosely attached to the springs and can easily be tilted up or down.
Thanks for the observations....
Uh, no comment on the anatomy remarks.....At my age , it doesn't really matter.
|Length is roughly 35 3/4" from u joint end to end. You guys still want to talk about the 1" movement?
I am standing on the naughty step! You are quite right, this is not the place for such smutty talk.
I am at work having a bad day. I just read your post while drinking tea and now the tea is on my computer screen and my day is much better. You may remove yourself from the naughty step. It did not come close to the ranks of smutty.
prop shaft measures almost exactly 36" from one tip of the fixed yoke to the other fixed yoke tip....
That 1/4" would make all the difference.
I'm going to adjust at the rear axle...I don't think 1/4" will hurt anything.
|Edward, did you find the rear axle out of position on the rear springs?. There is a locating bolt in the center of the spring locating plate. This and the rear spring U bolts through the plate pretty much set the position of the axle fore and aft. This generally gives some room for the splined shaft to move for and aft in the front yoke. This is necessary because of some up and down tilt movement of the axle due to torgue and spring action. If the axle is mounted to the springs properly, and you are still tight on the drive shaft length, you may have issues with the spring mounting shackles throwing the axle position off ?|
I think you have hit on the problem....I'm going to be pulling the springs and shackles, and replacing the rubber parts....
When I replaced the U-bolts about three months ago, I did notice that there could be slight fore-aft movement....
1/4 inch isn't very much, and it should be relatively easy to find it.
|Attached is a photo I took during my restoration that shows the front of the drive shaft. This may give some for reference. This is with chassis and engine weight on the springs.|
That looks more like 3/4"....I'm sure it will close up with the full weight of the car....Good looking chassis, by the way...Hope to be there by the end of next week.
|Could the rear springs have been reversed? The axle mount is not in the center of the springs. If the springs are reversed (end to end) the axle will sit too far forward.|
The distance from the center pin to the front should be farther then from the center pin to the rear?
I will check that, now that the springs are off the frame.
Sorry about the problems you've been having. I hope it's not too late to say this, but if a PO had fitted MGA internals to your rear axle case, about 1" would need to be taken off your propshaft body to restore sliding movement on the splines. My TF 1500 came back fom LA with these internals, a common mod. in the States, and I had to take the propshaft to a local specialist to turn the requisit amount off.
Just a thought,
|J C Mitchell|
|"The distance from the center pin to the front should be farther then from the center pin to the rear?|
I will check that, now that the springs are off the frame."
The opposite is true.
The springs are longer behind the axle than in front.
My TD has MGA internals in the rear axle. No modification to the propshaft is needed if the axle modification is done correctly.
Interesting comment - I've done tens of thousands of miles on the rear axle, so presumably it's been converted properly.
When it came to me the front splines were right up against the shoulder, allowing for no 'inward' movement, and reducing the length of the propshaft seemed a reasonable solution to me. Maybe I was wrong and the axle is too far forward? I've still got an original length propshaft which could be used in the future, but in the meantime..........!
|J C Mitchell|
|DB, JC, and all:|
I measured out the difference in the stock T pinion flange vs. the MGA R&P conversion I do and the MGA pinion flange ends up 3/8" further forward. While some suggest shortening the driveshaft 1/2" most of the time it is not necessary.
|Dave Clark Arizona|
Now you are telling me that the front of the springs are shorter than the portion to the rear?....That would mean that the drive shaft would be closer, than if the opposite were true....
I haven't measured yet, too busy removing old bushings, but I will do that today.
I'm thinking that my worn engine mounts, may be the culprits, since they look to be angled to the rear...Wouldn't take much to cause the "cramped" condition.
Looking at your first picture, it seems to me that your engine and gebox is too far back.
check the front mounting bracket on the engine.
Thoralf, Norway TD 4490
|Thoralf Sorensen (TD4490)|
|Hi Dave C,|
Thanks for info. re MGA internals - it ties up with the info. I got at the time from someone like you, but who does conversions here in the UK. On reflection I think I only had 3/4" taken off the propshaft - there must be some small variations from car to car.
The pin in the rear spring locates things down there, and there would have to be severe wear in the engine/gearbox mountings for that to have much effect. I suspect that where MGA internals have been fitted, it is the most likely cause of loss of spline movement, but I bow to people like you, who do these conversions on a regular basis. I shortened my prop some 10 years ago and there's been no problem.
|J C Mitchell|
Others recommend 1/2 be removed but really it seems only 3/8 inch would be necessary to put things back to factory proportions. I think most people don't bother to shorten it at all. This discussion is real good though as a way of explaining what people should look for if they have problems with a tight fit. Best bet is to correct those problems first then shortening of the shaft will probably not be necessary.
|Dave Clark Arizona|
Thanks for your further comments - when I first got the car from LA the splined end was hard up against the inward part of the propshaft - why no damage had occured is a mystery!
Is it possible to put MGA internals into the rear axle case, and by shortening the bevel pinion shaft slightly, achieve the original gearbox axle distance? Just wondered, but doesn't explain why mine may have stuck out more than 3/8"!
When it's warmer in the spring I'll investigate
|J C Mitchell|
|Well , with everything off the chassis, I will be able to tell if the new engine mounts, and re-bushing of the rear springs, will make up the loss of spacing...|
I have some engine "tidying up" to do first , and this will probably take quite a bit of time.
I'm glad I brought this up, as it has been most informative....
The dis-assembly of the rear springs has started, and the chassis has been cleaned, de-rusted, (happily, very little rust), and primed, and ready for chassis paint.
(see image). The PO had redone the entire front suspension and brakes,( thank you very much) so they were left in place, and bagged.
Thanks for the input.
Although it appears that MGA internals only result in approx. 3/8" projection from standard, have you checked whether this common conversion has been done on your car? It's easy to compare from the outside.
|J C Mitchell|
Considering that the tach shows about 4000 RPM at 55 mph, I would say no conversion has taken place on this axle.
Actually, where I live, this may be a benefit...Since we have almost no "flat" roads...Mostly pretty good sized hills and mountains...
If I even considered a change, it would be to the 4.55 gearing.
Thanks for your info. - good luck in sorting out the propshaft, and may your rebuild progress well, with not too many problems.
|J C Mitchell|
|J C Mitchell,|
I suppose it would be possible to machine the pinion shaft and thread it 3/8" further then shorten the pinion flange. It would be a lot of machine work compared to the easier shortening of the driveshaft.
I've just finished a 4.55 conversion that is not yet sold so perhaps now is the time??
|Dave Clark Arizona|
This thread was discussed between 23/11/2011 and 07/12/2011
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