Birty Dastards Jeep Club
Tech Forum => Workshop => Topic started by: bill99 on July 06, 2012, 11:53:45 PM
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Rear spring removal question
I am in the process of swapping out the rear springs on my 1999 XJ Cherokee 4 litre.
So far I have loosened off the u-bolts and the big rear bush bolts.
The question is regarding the front bush bolts, is there any pitfalls to watch out for here, they have been in there since new and putting a large breaker bar on them worries me due to the fact that the nut is captive in the chassis and the bolt could shear off, or the captive nut could strip out or spin.
What is the expert view on this, are they known to cause problems or do they just come out as planned?
At the moment they are soaking in WD40 and waiting for a break in the wet weather.
Any advice welcomed.
Bill
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drill a hole opposite the captive nut and soak with a releasing oil (WD40 is not the best), you can sort of get at the nut from a hole in the rail to squirt penatrating oil at it but the last really stuck one I just drilled a 3mm hole and kept soaking in every day for a week, cracked off easy then
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:iagree:
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WD40 is not a release agent. Use plusgas or something similar. Soak the whole thing and drill a small hole as mentioned. Use a single hex socket and a breaker bar. If you have soaked it for over a week then it should free itself. The pitfalls are the captive nut breaks from its place and the bolt turns. One other thing happens is that the bolt siezes to the inside of the bush. Either way some time with an angle grinder will be needed. Or you just could be lucky
Posted from my phone as its quicker than the pc connection
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50/50 with ATF & Thinners - its magic
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50/50 with ATF & Thinners - its magic
wtf :017: you feelin ok?
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I find WD40 works ok but their are proper releasing agents you can use as well. I suggest soaking everything and not just the nut - the bolt can seize in the bush so spray all around and hope some gets in there too.
I find a big breaker bar and muscling it seems to snap bolts more often than a smaller bar and sort of 'bouncing' it or even applying pressure and banging the end of the bar wit a hammer - like a manual and slower impact method. It could all be in my head but if it's really tight and I get a long bar on it with loads of pressure it normally just breaks something. I also like to get it moving a tiny bit and then reapply loads of WD40.
Sorry if the above is teaching you to suck eggs or whatever that saying is
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50/50 with ATF & Thinners - its magic
wtf :017: you feelin ok?
top tip from irishcj6, released rusty nuts on the Chief that hadnt been touched for 30yrs after about 10 mins soakin
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don't go drilling holes untill you have actually tried undoing the bolts , i've never had a problem
with them ,just a squirt of wd40 and a breaker bar.
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Oh well some progress, so far I have one spring off but I damaged the threads in the captive nut.
This was because the bolt turned out only far enough to come off the nut's threads then it hung up on the bush so the projecting blank part of the bolt got turned under pressure on the captive nut's outer few threads.
So can anyone tell me the thread size also any trick to get a tap in there and still turn it?
Thanks for all the advice so far
bill
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Just been thinkin, would it be possible to drill both bolts straight thru and replace with a single bolt ? The leaves on mine need done, but just haven't even looked properly at the set up.
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They are a UNF thread. So if your replacing then fit what you want ?
Posted from my phone as its quicker than the pc connection
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Hmm, i was expecting a UNF or UNC type thread but after finding a Chrysler pdf parts list it has the 99 jeep as having a 14 mm by 2 mm thread on a 120 mm long bolt.
Guess i will have to wait till Monday and check with a dealer.
bill
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To be honest if the jeep is on jacks take the other bolt out and use that as a reference. On my mk1 they were not metric. if your replacing the bolt and nut anyway just fit what you want.
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Yeah you can use any bolt for the back bush but the front captive nut means using whatever thread is in there, in my case for a 1999 it is 14mm with 2 mm pitch.
Anyway I got hold of a 14 mm tap today and managed to clean up the threads by just getting a small open end spanner on the tap. We did a temporary fit of one spring with some bolts made out of screwed rod, so just need to get new bolts ordered tomorrow.
By the way getting the spring in place and lining up the bush holes with the shackles was quite a job, I was expecting to just hold them up loose and pop in the bolts but I had put one bolt in then load the springs with the jack to get the length right for the other bolt to go in, and that was with the rear shackle pushed forward as far as it will go, is that normal? Or is there a better way?
cheers
bill
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better way is to put front in first..........
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Yeah that is what I did, front in first and found it short at the back so I had to put some load on the spring with the jack pushing up on the axle to level it out a bit to reach the rear bush swinging on a loose shackle. It worked but then I had issues getting the axle centred to get the springs centre bolt located in the axle before doing up the u-bolts.
You can tell I don't do this stuff very often, and by the way its in the garden, on a gravel drive, on jacks and axle stands and in the rain, fun or what.
bill
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DONT tighten the front and rear spring and shackle bolts untill the wheels have been refitted and the jeep is sitting on them. this allows the jeep to find it's level THEN tighten the spring bolts.
If you tighten them before dropping the full weight of the jeep you will have the bushes in a shear condition which will cause premanture wear and result in them splitting
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Yeah that is what I did, front in first and found it short at the back so I had to put some load on the spring with the jack pushing up on the axle to level it out a bit to reach the rear bush swinging on a loose shackle. It worked but then I had issues getting the axle centred to get the springs centre bolt located in the axle before doing up the u-bolts.
You can tell I don't do this stuff very often, and by the way its in the garden, on a gravel drive, on jacks and axle stands and in the rain, fun or what.
bill
sounds normal.
and as said above only tighten when set on the ground
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OK so this is normal then.
Thanks to all for the advice, new bolts ordered and should be here tomorrow.
cheers
bill