hi
my alternator pulley is defective, the outer ring turns loose, my question is, instead of buying a new pulley if i weld the outer ring to the center of the pulley to lets say turn it in a one piece pulley does this will generate some kind of problem?

i know that i can buy a new pulley, i already bought one second hand alternator that works perfect, but for the other cars that i know the pulley is a one piece pulley and not a clutch kind pulley and they work perfect, thats why i do not understand why this pulley works this way and maybe if i weld it there will be no problem, maybe one specialist can give me one answer and tell me if i can do this.

thanks in advance

 

Some Alternator pulleys have an inbuilt spring like mechanism that takes up the shocks in the belt drive. The name deludes me at mo. This makes it run smooth. So welding it may cause problems. These pulleys are available on Flee-Bay if that helps. Decoupler pulley I do believe.

 

yep i know, i bought a second hand alternator instead, but the alternator that have the pulley damaged is in very good condition only pulley is dead, in my mind i presume that this kind of pulley is used because of the system used regarding belt tension that is not fixed but instead a spring, but in this case it will create problem only when i start engine, but nothing of too serious, but i could be wrong, anyone with more info?

 

If you DID weld the pulley together, what do you have to lose?
Many people who have run up against disintegrating shock absorbing Renault flywheels in the 1.9 diesel engine wish they had had a solid flywheel. The cost of fixing those dual-mass flywheels is crucial.
I'd take a chance....

Leedsman

 

Hi There
That explains a lot my last car before the voyager was a Ford Mondeo Est diesel that had a auxiliary belt vibration on tick over and was quite noisy i replaced the tensioner which quietened it down but not completely the bottom pulley on that was one like the one on the voyager alternator i did replace it but it was secondhand on those cars they sell the tensioner belt and bottom pulley as a kit which is what i should have done..

Anyway my point is that was probably the reason it was still noisy because i did,nt replace the pulley with a new one and the belt was still vibrating but not as bad

Pete.......

 

Do not weld the overriding alternator clutch pulley....it's there for a reason, and that reason is that the inertia of large alternators is by far the biggest inertia driven by the engine auxillary system, without the overriding clutch engine speed fluctuations are passed directly into the alternator, this places a lot of stress on the belts and tensioners, as the belt is effectively trying to speed up and slow down the alternator directly in relation to engine speed changes. With the overriding pulley only accelerating torque is applied to the alternator inertia.

If you weld it it will work, but your belt & tensioner life will be short, the alternator bearings will also have a shorter life.

 

Good points MatGriff, maybe it's possible with a bit of ingenuity to repair the shock absorbing system on the pulley, thusly saving money?
A look on E-bay might show a suitable part at a reasonable price -- as in the ABS contemporary posting here.

Leedsman.

 

The pulley is well sealed... I replaced mine last month & believe me it's a pain in the ***, even with my impact gun I really struggled to get it off, because you can't hold the alternator rotor.

I ended up welding the pulley, holding it in a vice an using the impact gun on the 10mm hex head of the rotor itself.

Turned out to be the alternator bearings themselves that were the problem.

I got a 2nd hand unit, and I'm now in the process of re-building the original alternator.

Parts for this denso alternator are not easy to find :-(

 

From what I've seen in the past with alternator bearings, they were simple straightforward roller bearings. In an engineering city like Leeds here, you can buy these over the counter, real cheap. If you get the bearings out and take them to a bearing supplier for a match-up, should be a cheap fix. So... makes sense to investigate and fix for a few quid. I was quoted £380 for a replacement alternator! Fortunately, turned out the alternator was not at fault in my case. (Which I reported here on this site). It was the charge control system for the alternator being designed for continuous rather than intermittent vehicle use.

Leedsman.

 

The front bearing is a standard size and readily available, the rear one is not... and is pretty unique to automotive alternators, however I have managed to get one. The slip ring assembly is very difficult to find outside the USA