WTAF is causing my 1HD to throw belts? (1 Viewer)

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Got you. No, the bracket on mine has round holes in it :)
 
I am making very slow progress. So pulled the timing belt and tensioner off, broke my chain wrench trying to remove cam pulley and eventually conceded I'd have to pull the rocker cover and do it properly. The FT motor however has a bridge casting in the way of the machined flats on the camshaft, so had to go and buy a 27mm open end. Which didn't fit either, so ground it down until it did. I reckon it took 200+NM to release. Finally recovered the WP. It's ugly, but not faulty. No play in the bearing and no impeller contact with housing.
IMG_20220127_121141122_HDR.jpg

Also pulled the thermostat housing off and recovered the alt bottom bracket, which looks fine:
IMG_20220127_114717763_HDR.jpg
IMG_20220127_114618109.jpg


I'm not really convinced I've fixed anything at this stage, small crack in adjuster mechanism and mud in wp pulley aside.
 
I am not sure what you mean by mud 'in wp pulley aside'? Do you mean there was mud in the 'V' groove. or mud between the pulley and the face of the water pump? The crack in the adjuster would not allow the alternator to run at an angle, alignment is controlled by the bottom bracket, I see the bracket was missing a bolt or it was not tightened allowing the bracket to skew, note there are no 'witness' marks where the bolt was removed from the rearmost part of the bracket. If the adjuster bracket was damaged it would have to be twisted and quite some way to reach the belts and cause damage, and once done up the belt tension would be maintained by the clamping force between the alternator and adjuster bolt. Perhaps you were over tightening the belts, and I also mentioned the AC belt could be thrown into the works?

I think you need to seek advice from an experienced/professional mechanic who can physically look at the vehicle if you have further issues.

Regards

Dave
 
There was some mud inside the back of the water pump/fan pulley. I see what you mean by 'witness' marks, but that's the front bolt hole missing those isn't it? The rear one had a washer. They were tight. Agreed re upper adjuster bracket. I didn't make mention of the AC belt because I haven't fitted it recently while I try to iron out this problem..

I'd love to entrust this work to someone else, but every workshop I've ever used in Perth, where I live, have been hopeless - rattle guns, crossed threads and a complete lack of care. It's a problem born of crazy high salaries for mining support workers which basically leaves smaller operators choosing between ex cons and imbeciles for help.
 
Makes you wonder how the mud got between the pump running face and the pulley, You would have thought it would have dried out and crumbled and the pulley then become loose?

Regards

Dave
No, not between the mating faces but in the back of the pulley assembly. Here:
IMG_20220127_155224912_HDR.jpg

No uniformally distributed, I'd guess there was 20grams or so. I'd imagine that eccentric mass would be sufficient to add an imbalance, but it's been there for 30k or more and doesn't seem to have flogged the WP bearing. I'll be able to put some of it back together this evening.

I've noticed that the WP that was fitted had a steel gasket with hylomar, and my replacement has a paper gasket. I'm going to see if I can get a reasonable measure from the face of the block to the pulleys and see if that 1mm of difference is material.
 
That would not have thrown a belt, and re centrifugal mass I don't there is enough diameter there to create the amount of force to damage the belts or bearings.

Anyway, just get it back together and see how it goes.

Regards

Dave
 
I’m curious as to what coolant you were using, because by the look of the wp impeller it’s not doing the job?
 
Having a matched set of belts start out aligned and quickly misaligning is a quick indication that one of the belts is slipping.
Which one is GAINING on the other IN THE DIRECTION OF TRAVEL.
If the rear belt is gaining,
then it the s tighter, indicating that the tips of the shafts point together and are not parallel.
No, not between the mating faces but in the back of the pulley assembly. Here:
View attachment 2906683
No uniformally distributed, I'd guess there was 20grams or so. I'd imagine that eccentric mass would be sufficient to add an imbalance, but it's been there for 30k or more and doesn't seem to have flogged the WP bearing. I'll be able to put some of it back together this evening.

I've noticed that the WP that was fitted had a steel gasket with hylomar, and my replacement has a paper gasket. I'm going to see if I can get a reasonable measure from the face of the block to the pulleys and see if that 1mm of difference is material.
Was the replacement alternator a Toyota (Denso)?

If aftermarket, it's possible the pulleys are not inline with the other pulleys on the engine.
 
Good question. I don't know, but it's green and clean, so I too was surprised to see the condition of the wp. Was supplied by engine builder, as after I got the motor back and refitted I discovered it had no oil pressure so I put the whole truck on a flat bed and sent it back. Turns out they forgot the oil pump. Not great, but in fairness the rest of the job seems solid, the motor sounds good.
I've got the wp, alt brackets, thermostat and timing cover back plate back on now. Should have the rest back together tomorrow.
 
Having a matched set of belts start out aligned and quickly misaligning is a quick indication that one of the belts is slipping.
Which one is GAINING on the other IN THE DIRECTION OF TRAVEL.
If the rear belt is gaining, then
Was the replacement alternator a Toyota (Sensor)?

If aftermarket, it's possible the pulleys are not inline with the other pulleys on the engine.
Then what :)

Replacement alt is Bosch. I've had 3 years of it not throwing belts mind you.
 
Then what :)

Replacement alt is Bosch. I've had 3 years of it not throwing belts mind you.
You have stated the following:
* Alternator changed 15K miles / 3 years ago
* Alternator Pulley is hot
* Belts are rolling
* Harmonic Balancer changed in last 1000 miles AFTER belt problems started.
* Fixed alternator cracked bracket


When you install the next set of belts and get them to tension, align the labels and watch after a few rotations of which direction one belt gains VS the other. This can give an indication of how much misaligned the shafts are.

If the alternator pulley is hot, there are multiple things that can be the issue. Misalignment, load, alternator bearings.

It's very possible the bearings on your "new" alternator are on their way out. 5000 miles/year is not a lot, which means it sits a fair amount. The bearings in the Bosch alternator may have decided it's done. Is there another idler on the alternator belt system? I'm not familiar with this particular engine, but I know the 1FZ-FE can throw belts if the idler is dragging.

If the alternator is under a heavy load, the bearings are dragging, and you are towing heavy with sudden changes in RPM or long hard pulls with a lot of electrical load, it may be stretching or slapping the belts.

I would seriously look at changing the alternator if all the idlers and alignment proves to be good.
 
My belts went out of alignment pretty quickly however I don't see it as a problem. If you consider the pulleys may have slight variations at the point of manufacture, so there could be a variation in the crank, water pump, alternator and so forth, each tiny variation allowing the belts to 'drift' out of alignment.

Regards

Dave
 
Exciting news. I drove for 15mins at 2 - 3.5k rpm and the belts have stayed on. At this stage I've left 2x batteries disconnected for justin, though I'm pretty sure they're fine given their measured capacity. No idea what's resolved this issue - I guess the smart money has to be on the water pump. As a point of note, the belts do not remain aligned, even from idle. Just out of interest I'm going to dig out a strobe and see if I can't spot which one's 'faster'.
 
Exciting news. I drove for 15mins at 2 - 3.5k rpm and the belts have stayed on. At this stage I've left 2x batteries disconnected for justin, though I'm pretty sure they're fine given their measured capacity. No idea what's resolved this issue - I guess the smart money has to be on the water pump. As a point of note, the belts do not remain aligned, even from idle. Just out of interest I'm going to dig out a strobe and see if I can't spot which one's 'faster'.
Glad to hear it's resolved. Don't worry about the belts going out of alignment, perfectly normal. Those things are moving quick. People have already mentioned about various imperfections that contribute, but there's the obvious ones I haven't seen mentioned:
1. The belts are flexible
2. The belts aren't precisely the same length

A few hundred rotations multiplies those differences a few hundred times, which is why the belts drift. They always do. Perfectly normal, and perfectly harmless.
 
To add to BILT's breakdown, the following have been replaced at some point
- harmonic balancer. OEM? If no, what brand?
- water pump. Brand? (Doubt OEM. OEM water pumps I've dealt with have had nylon, or stainless steel impeller)
- Alternator, Bosch

Three critical components that are all non OEM (assumption), if there's misalignment with v grooves or differences in machining quality control, could be a combination of minor factors.

I agree the hot alternator is a definite clue to something not right there too
 
To add to BILT's breakdown, the following have been replaced at some point
- harmonic balancer. OEM? If no, what brand?
- water pump. Brand? (Doubt OEM. OEM water pumps I've dealt with have had nylon, or stainless steel impeller)
- Alternator, Bosch

Three critical components that are all non OEM (assumption), if there's misalignment with v grooves or differences in machining quality control, could be a combination of minor factors.

I agree the hot alternator is a definite clue to something not right there too
HB and WP are oe parts. HB always was, WP just changed.

Today I've connected one of my aux batteries and re mounted the ac belt.
 
As far as matched belts are concerned, that only means the pair are within the predetermined tolerance spec for being different. I’ve seen them walk pretty quickly. About the only test you can do is to swap their position and try and determine a difference.

From the beginning the hot alt caught my eye and immediately thought of a problem with the batteries or an internal grounding fault within the alternator itself.
 
We managed 120km yesterday in a mix of highway and suburban roads with ac on, and all looks good. Incidentally after reading plenty of arguments about gaskets I went with a dry paper gasket on the WP having cleaned up the mating face with high grit emery cloth. No leak at this stage. Will flush coolant shortly.
 

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