MRG1965 Posted July 14, 2014 Report Share Posted July 14, 2014 HI, I'm new to the register after recently purchasing a 1964 TR4. One of the jobs to do is to attend to the leaking axle pinion oil seal, which seemed like a straightforward job until I started to read up on the required torque setting for the pinion nut. Looking through various threads it seems to be a very confusing subject with reference to mistakes in printed manuals. I have read that the torque should be 15-18 Inch/Lbs which equates to around 1-1.5 Ft/lbs. Now it is many years since I used a torque wrench in anger, but 1.5 Ft/Lbs seems to me to be very slight and I could well over tighten the pinion nut with just the weight of the torque wrench itself without even pulling on it. Any assistance from the group would be much appreciated as I'm sure this is job that comes around on a regular basis and I don't want to damage the bearings or crown wheel and pinion gears by under/over tightening. Regards Mark Quote Link to post Share on other sites
Motorsport Mickey Posted July 14, 2014 Report Share Posted July 14, 2014 Hi Mark, These figures are shown in the Workshop manual (correctly) as 85-100 lb ft (that's foot), whatever other manuals you have that show differently need chucking. Not quite clear what threads have shown anything differently, I thought these were well established figures. Mick Richards Quote Link to post Share on other sites
Motorsport Mickey Posted July 14, 2014 Report Share Posted July 14, 2014 Mark, I've sent you a PM ( Personal Message) via the Personal messenger service. To review go to the top of the page and look for your name, there is a little triangle to the right of it which when pressed will give you a drop down and show you a PM to you from myself. Have a read and send me one back if you want. Mick Richards Quote Link to post Share on other sites
peejay4A Posted July 14, 2014 Report Share Posted July 14, 2014 (edited) According to my (reprint) WSM the 15-18 lb-in torque is that required to check that the pinion pre-load is set correctly - page 3.111 in my book. The pinion flange is 85-100 lb-ft as Mickey says and that's in the torque settings part of the manual at the front. So my WSM seems to be OK in this respect at least. Edited July 14, 2014 by peejay4A Quote Link to post Share on other sites
AlanT Posted July 14, 2014 Report Share Posted July 14, 2014 By the time you have undone the nut, you will know that 100 ft lbs is more than you can easily do, layng on your back under the car. Quote Link to post Share on other sites
MRG1965 Posted July 14, 2014 Author Report Share Posted July 14, 2014 Many thanks all. Yes 85-100 Lbs/Ft is very much in the area I would have expected, so very happy to torque up now, but yes I agree that's a lot of pressure to try to generate on my back on axle stands, but hey who said life was easy :-) Thanks for the offer Mick, I've replied to your PM. Mark Quote Link to post Share on other sites
BlueTR3A-5EKT Posted July 14, 2014 Report Share Posted July 14, 2014 (edited) And if you are worried about pinion bearing preload I have the torque gauge to check it. Peter W PS you will need the axle the car to easily adjust it though. Edited July 14, 2014 by BlueTR3A-5EKT Quote Link to post Share on other sites
dingle Posted July 15, 2014 Report Share Posted July 15, 2014 It is my understanding that the pinion bearing pre-load spec.(15-18 lb in.) is checked without the crown wheel or oil seal fitted, as the drag of those components would give a false reading. Berry Quote Link to post Share on other sites
cbxman Posted July 16, 2014 Report Share Posted July 16, 2014 Hi, Just to add my halfpenny worth.. When I had my MOT the other day, I was under the car with the test guy, when I checked the play in the Pinion flange. I had about 1/2 mm up and down movement on the flange. When I got home I picked up on this tread, and like the OP was rather confused by the various torque settings. I went over to Manvers Triumph (just up the road for me) and asked their opinion. They said that any slop in the pinion flange is almost entirely due to a loose pinion nut 9 times out of a ten. My instructions were to put 120 ftlbs torque onto the nut, whilst holding the flange with their own special tool (a bar with two high tensile steel bolts welded to at the same pitch as adjacent flange bolt holes). Then put a split pin in the castellated nut. They were quite clear an positive that I almost went away with a flea in my ear!! I duly did as I was told. After removing the prop shaft, I found that the pinion nut was loose, maybe 10 ftlbs with no split pin. I torqued to 100 ftlb as I couldn't manage much more whilst lying flat on my back! 100ftlbs is what the haynes manual quotes so I'm happy with that. Then I inserted a split pin. No slop in flange now and no drag. Everything turns freely....smug feeling. After a test drive...returning borrowed special tool to Manvers, I found that the little tune that the rear axle plays to me is much more melodic and predictable. The 18 inchlbs figure people have been quoting is for helping determine the original shims selection during assembly at the factory and any subsequent rebuild, and nothing to do with the flange torque. I hope that clears up some confusion. I was certainly confused until now Have fun Quote Link to post Share on other sites
cbxman Posted July 16, 2014 Report Share Posted July 16, 2014 Just need to add that my TR4A is a live axle version, i.e. a TR4 axle. I believe that the IRS diff has a similar set-up, but I can't be sure Quote Link to post Share on other sites
AlanT Posted July 16, 2014 Report Share Posted July 16, 2014 When you see a thumping great nut an inch or more across its a big clue that its for tightening until you eyes pop out. On the other hand a poor little 1/4in thing wants the delicate touch of a Japanese Geisha. Quote Link to post Share on other sites
Motorsport Mickey Posted July 16, 2014 Report Share Posted July 16, 2014 AlanT, You describe it so nicely, very lascivious. Just as an aside and picking up on the 1/4 inch Geishas plaything, have you stumbled upon the "Trailing arm" thread regarding a jig for drilling the rear trailing arm hub fixings where these poxy 5/16th UNF studs into alloy give us problems ? Mick Richards Quote Link to post Share on other sites
AlanT Posted July 17, 2014 Report Share Posted July 17, 2014 Are they as big as 5/16. My mental image is 1/4in. They are weedy I know that. This is the only thing on the whole car I stripped a thread on. I'll look for the topic. Quote Link to post Share on other sites
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