Thread: It went thud..............

Broken centre bolts are not uncommon on leaf spring vehicles of all kinds, including Landrovers. They almost always result from loose U-bolts, and it should be noted that checking the tightness of U-bolts is listed as part of the 20,000km service in my S2a owner's handbook.

John

Originally Posted by JDNSW

Broken centre bolts are not uncommon on leaf spring vehicles of all kinds, including Landrovers. They almost always result from loose U-bolts, and it should be noted that checking the tightness of U-bolts is listed as part of the 20,000km service in my S2a owner's handbook.

John

And don't just check by tightening them, these buggers took a hell of a lot of heat to get the nuts moving, they can feel tight but not have much clamping force at all. Loosen them then tighten them.

wait till you have it happen on the rear and it walks far enough forwards that the spline runs out of travel.....

that makes some very interesting noises....

Originally Posted by Blknight.aus

wait till you have it happen on the rear and it walks far enough forwards that the spline runs out of travel.....

that makes some very interesting noises....

Been there, done that - just as the sun was setting. Just before the propshaft let go, I was wondering why the vehicle was crabbing up the track. Salisbury pushed back into fuel tank and pin holed rear plate on Salisbury. Fuel tank OK.

Had a spare front centre bolt (rear ones are thicker). Passed winch cable under 109 back to diff to pull it back forward. Slipped the splined propshaft together and bashed the leaves back into alignment with an axe before refitting centre bolt. Got back to camp after 9pm. Welded up pin hole in diff when I got home and replace centre bolt with rear type.

All Fun

Originally Posted by jimbo110

And don't just check by tightening them, these buggers took a hell of a lot of heat to get the nuts moving, they can feel tight but not have much clamping force at all. Loosen them then tighten them.

Yes, and note that while these U-bolts will stand a lot of tension, they are quite easy to twist off if the nut is seized on. Note that they come in both BSF and UNF threads (possibly even metric on late S3 or after market). Locking may be from plates with bent tabs, double nuts or self locking nuts. Use of lock washers does not seem to be secure enough. I prefer the double nuts, as these can protect the threads, which otherwise tend to get butchered by rocks if protruding beyond the end of the nut.

John

Originally Posted by JDNSW

Yes, and note that while these U-bolts will stand a lot of tension, they are quite easy to twist off if the nut is seized on. Note that they come in both BSF and UNF threads (possibly even metric on late S3 or after market). Locking may be from plates with bent tabs, double nuts or self locking nuts. Use of lock washers does not seem to be secure enough. I prefer the double nuts, as these can protect the threads, which otherwise tend to get butchered by rocks if protruding beyond the end of the nut.

John

John, unless the U bolts are near new, I dont bother trying to undo them, If they wont come off with the rattle gun I just oxy cut them off and replace them with new ones. If they are tight enough that they wont come off reasonably easy, then removing them usually damages the u bolt and the threads, the amount of time saved fitting new u bolts more than makes up for the cost, Regards Frank.

Originally Posted by Tank

John, unless the U bolts are near new, I dont bother trying to undo them, If they wont come off with the rattle gun I just oxy cut them off and replace them with new ones. If they are tight enough that they wont come off reasonably easy, then removing them usually damages the u bolt and the threads, the amount of time saved fitting new u bolts more than makes up for the cost, Regards Frank.

Perhaps - but cost vs time may be a secondary consideration when the nearest supply of U-bolts is 500km away, it is Friday night and they don't open till Monday and you need the vehicle Saturday - or the nearest civilisation is 100km away, and if you can't fix the broken centre bolt, its a long walk. And you don't want to break the U-bolt.

John

John thats' true, but the majority of people pay to have their car fixed and it's certainly cheaper and a better job to boot.
After spending a couple of hours with a breaker bar and a 3' pipe extension and half a gallon of Penetrene, and a crick in the back, the threads are usually cactus, along with the nuts and the bolts have been twisted, it is much safer to replace the lot, at least you will be able to tighten a new set back to what it should be.
Even if it is Friday night and you need the car the next day, there is no guarantee that one of the bolts wont break or the threads will be buggered and unless you have a good tap and die set you are stuck anyway, Regards Frank.