Replacing my 1991 2CT aircon belt I noticed play (end and side) in the pas pump shaft the oil seal was dislodged. No fluid escaping. I assume this explains the steering-related hissing the past months during the first few minutes from cold and I intend to rebuild the pump. I obtained the recommended 6303-2RS bearing easily enough, but have a few questions...
Why does this failure occur? Might the belt be easily over-tightened? or are lots of owners going to be rebuilding these pumps? - more reason to ask these questions ...
Any tip for holding the pulley to undo the retaining nut? I tried before but couldn't do it - afraid of breaking the pulley.
The new bearing is sealed both sides itself (I gather "2RS" means two rubber seals). I see one pump sketch with an outer seal and one with an inner seal. My outer seal is there but not sealing. Am I mistaken to assume that either the bearing seals are enough, or that I have an inner seal as well which is working fine?
Once the inside circlip is removed does the shaft and bearing pull out, leaving the pump rotor inside? Is there any chance of doing that with the pump in situ?
Is the pump only fixed by the long "hinge" bolt and the belt tensioner bolt running in the slotted arm? Can it be got out without removing the alternator? Where is best to disconnect the hoses?
- (#8790) Dave (Sussex), 25 Feb 04 08:12
Dave
you need the steering section of the Van manual. Its 2.8 meg so if you send your works email addy to dave@automatic-windings.co.uk I will send it to you.
- (#8790) dave Bright (Bournemouth), 25 Feb 04 08:34
Thanks Dave, I didn't think of reading that. I presume you mean what's under "Toyota factory repair manual - '87 Van" in the Tips & Tricks section of the USA Van website. I've printed off pages 29-37 on the pas pump direct from the steering section there.
I read "push on drive belt to hold pulley" elsewhere - I tried that and just made the engine turn over, backwards.
Does no mention of removing the alternator mean its not necessary?
These pages are about removal, complete disassembly and inspection of the pas pump. I wondered if anyone who's done it can comment on whether "Using a plastic hammer, lightly tap the shaft out of the front housing" might possibly be done, as a shortcut for replacing the bearing, by applying gentle impact evenly on the back of the pulley-securing nut without removing the pump and splitting the housing. Then there's the issue of whether it'll all go back together, I know.
- (#8790) Dave (Sussex), 25 Feb 04 10:02
Just the two bolts, plus hoses, yes- Alt. can stay.
Pulley nut may be tight. Impact wrench or failing that a hammer and cold chisel applied to the edge of the nut, would be best to shock it into submission.
You'll not rebearing it in situ.
I seem to recall a couple of circlips being involved, but don't quote me on that. (looks up cd...)
Yes. The pulley has to come off to get at the circlip that holds the bearing outer race in.(behind the outer oilseal)
Be careful with the oilseals, but they should be standard sizes too; assuming a second inner seal does exsist (don't know what model/ year you have- two pumps one with a tapered shaft, one splined)
- (#8790) david miller, 25 Feb 04 10:27
"Might the belt be easily over-tightened?"
Why definitely. When I replaced my drive-belts I did the usual 'does it feel tight' measurement as applied to all my vehicles in my 30 years of servicing vehicles. Not so the Townace. Too tight, and I managed to make the aircon pump bearing squeal like hell. If you check the manual, each of the three belts has a recommended tension and it would appear to be folly to ignore the specs.
- (#8790) Ian Dunse (Derbs), 26 Feb 04 03:19
Thanks everyone, I'll have a go on Tuesday if my fingers don't freeze off, hoping to defeat that pulley nut - no-one's saying it'll harm the engine, fuel pump etc to be turned backwards a bit when I clout the nut - and extract the pas pump from under the alternator.
Realistically 'does it feel right' to 30/40 years of experience is about all you can do with belts - I've used tension gauges on radio mast guys like the one pictured in the Toyota manuals but is it worth getting one for these belts? how else can you reliably measure force and deflection at the same time? I suppose it's worth thinking about if it's a choice between rebuilding pas pumps and getting the belt tension right. I must say all the belts struck me as tight when I checked them.
- (#8790) Dave (Sussex), 26 Feb 04 06:03
Typical deflection used to be quoted as about 10mm on the longest belt run for many cars. They vary on the Townace for each of the 3 belts. I have to admit to being very rough when measuring mine, using a measuring rule.
I spent ages adjusting each one so as to not be too loose or too tight. After all it's not a simple 5 minute job to keep removing the floorpan to remove the belts is it.
- (#8790) Ian Dunse (Derbs), 26 Feb 04 06:56
I've always gone for the minimum necessary tension when adjusting belts- just tight enough that it doesn't slip or slap. Having to consider other options now in the Grand Vitara- the HDI engine has an auto tensioner for the serpentine, but you have to preload it to a certain level. PSA thankkfully have that one sorted, you put a bar in through a hole and the tension is correct when it comes loose.
Cambelt is another issue- only way to check or adjust is with one of them trendy new SEEM deflection gauges- they reccommend the electronic one...
- (#8790) david miller, 26 Feb 04 11:08
For the record - I fitted the new bearing in the pump as planned.
Swing the pump up and fix it in it's highest position for the best access to the pulley nut, as well as to get the belt off.
Disconnect the hoses next so they don't obstruct the pulley nut quite so much. The union in the outlet hose was awkward, I needed a 22mm (7/8in) open-end (& a 17mm for the part that rotates). The clip on the inlet hose was the least accessible way round.
You have to get the pulley off to be able to remove the long bolt on which the pump hinges. To get the pulley nut off I prevented the (splined) pulley rotating by wedging an open-ended spanner between one of the holes in the pulley and the adjacent chassis member. There really wasn't enough room to use an impact wrench.
With a bit of wiggling the pump then came out, upwards, from under the alternator. There is an O-ring between the halves of the pump body.
The large inner circlip retaining the bearing in the pump case is very sturdy and you need some good internal circlip pliers. The snap ring on the other side, which stops the shaft pulling out of the bearing (as if) puzzled me. Getting it off, carefully along the shaft, seemed to deform it so that when I put it back on later and squeezed it into its groove it wouldn't come off but it was much sloppier than when I started.
The whole job cost less than £20 (bearing and fluid) and since it was little more work than replacing the whole pump I'm glad I did it that way. Nick of time I think, the old bearing only had 7 of the 12 balls left in it and it fell apart. I had to grind into the inner race to get it off the shaft.
There was a seal further inside, which I left alone, and I didn't dismantle any of the impeller section.
- (#8790) Dave (Sussex), 4 Mar 04 10:07