I posted a question a while back asking whether anyone had replaced the bearing in the fan pulley on the Puma engine. As it seemed no-one had done this, I thought I would post my findings so that others who want to do theirs can have the necessary parts on hand before starting the job.
I gave all the idlers a spin when I was fitting a new fan belt as part of my trip preparation. most of them sounded and felt okay, with the exception of the big idler pulley that the fan is mounted on, and the smaller pressed-metal idler at about 10-o'clock from it. (Excuse the mess. This photo was taken just after I had knocked my funnel over whilst filling with oil from a 10l container) http://www.aulro.com/afvb/attachment...1&d=1400034546
I got prices from a LR dealer, the smaller idler was about $100.00 so I went ahead and ordered that one. To replace the big idler from Land Rover, it is supplied as an assembly that includes the big cast plate that the other idlers are bolted to. I assume that LR dealer workshops are not expected to own a press. The whole thing is priced at about $550.00 http://www.aulro.com/afvb/attachment...1&d=1400034643
I was not about to pay $550.00 for a whole lot of parts that I didn't need, without having a fair crack at dismantling it and replacing the bearing. Worst case would be breaking the casting, thus no worse off.
I needed to replace the radiator in the 130 due to the core having been rubbed through by the fan shroud (will post separately about that issue), so waited til I had all the parts and set about doing both jobs at once.
With the fan belt off, the tensioner is removed, as is the black 'Y'-shaped bracket that supports the front of the engine top cover. I unbolted the smaller idler from the cast plate before unbolting the plate from the engine- can't recall whether any bolts are hidden behind this idler or not.
There are 3 or 4 8mm bolts that face the front of the engine, plus 2 6mm bolts that go in from the sides of the plate at the bottom left-hand and bottom right-hand corners. the one on the right-hand side is proof that modern vehicle engineers have a grudge against mankind. http://www.aulro.com/afvb/attachment...1&d=1400034708
By partially undoing the 3 bolts that mount the alternator to the engine, I was able to wriggle the alternator out about 15mm so that I could get a 10mm ring spanner on this bolt.
With the assembly on the bench, I tapped a thread in each of the 4 holes in the face of the pulley in order to attach a puller. The threaded holes can be seen in the second photo, above, which was taken after I tapped them. (I think I tapped them to 7/16UNC, can't remember for sure. Only needed a very slight enlargement of the existing holes with the tapping drill).
I gently heated the centre of the pulley then pulled it off the shaft, over the fan thread. It came off nice and easily using a simple gear puller with an adaptor made from scrap, in this case an old pump flange, to align with the 4 holes in the pulley. http://www.aulro.com/afvb/attachment...1&d=1400034761
I then gently heated the cast plate, and after taking the chill off the whole thing to avoid cracking or distortion, warmed up the area around the bearing and then pulled it out from the rear, before pulling the shaft out of the bearing. This photo shows the dismantled components: http://www.aulro.com/afvb/attachment...1&d=1400034808
The bearing is a double-row ball bearing, NACHI part number 30BG05S5G-2DS 090604. My local bearing outlet ordered it based on the dimensions; outer diameter 55mm, shaft diameter 30mm, width 23mm. They had it next day, price was $50.00.
I seem to have maxed out the photo upload allowance, so I'll continue in the next post.
Assembly, as they say, is the reverse of disassembly, with the exception that, in hindsight, it would have been easier to press the shaft into the bearing before pressing the bearing into the housing.
I used Loctite assembly fluid on all the mating surfaces (if doing this job, make sure any loctite is thoroughly cleaned off the fan mounting thread at the end of the job, otherwise you would probably need an angle grinder next time you want to take the fan off).
When installing the new bearing into the casting I put the bearing in the freezer for a while then gently heated the casting before pulling the bearing into the hole.
Like LR workshops, I don't own a press, so the whole job was done with one puller and some improvised arrangements of bolts, washers and sockets to pull things into place. I had to slightly enlarge / clean-out the centre-hole in the shaft to allow a long 8mm bolt to go through, which I then used to pull the shaft both out and back in.
There were only two notable exceptions; the crude puller plate shown above, plus where I had to make a special tool to press the bearing out of the housing. This is a simple stepped slug where the smaller o.d. (29.5mm)sits in the inner race of the bearing, the larger o.d. (39mm) clears the hole in the casting and the i.d. (14mm or whatever) allows passage of a bolt to do the pulling. http://www.aulro.com/afvb/attachment...1&d=1400035303
I'm happy to loan this to anyone planning to do this job, just PM me and I'll post it at your expense, post it back to me when you're finished. Not everyone is fortunate enough to have a lathe at hand when they need this sort of thing.
A simple enough job with mostly basic tools plus a simple puller, some long bolts and washers and the two special tools made for the purpose. I was expecting to have to use the lathe to make several puller adaptors, but my trusty socket set provided almost all the arbors required.
I reckon if I had had the bearing and special tools on hand, this would have been in and out in around 3 hours. I had the vehicle in dry dock for a few days with a combination of jobs in progress, so didn't take note of how long this particular job took. Pretty sure it would justify the $500 saved.
Thanks Pod for the article. I just bought a '10 Puma 130 a couple of days ago with 47k km. I had the top fan shroud off to detail a few things & noticed that the lower shroud, r/h cnr. was rubbing on the rad. core also. First job tomorrow b4 getting the r.w.c. This prob. is gonna sell a few rads! I'm chasing a w/shop man. for this vehicle, has anybody found what they think is a good one? I've done the same b'ing mod. on a couple of 300 tdi's. thanks Ian
Reply With Quote
Bookmarks