RussB

When one orders an alternator belt for a 5000CSTQ, most aftermarket parts sellers these days supply a Contitech 11.2 x 820 mm belt. This works --barely -- in my car (which is fitted with a 110 Amp Bosch alternator).

The problem is that the 2 inch diameter plastic opening for the cooling air presses directly upon the cast iron boss from the engine block. There is not even one or two mm to allow me to fit the cooling hose. I'd guess that even a 11.2 x 830 mm belt would give me enough room to mount the cooling hose. Tomorrow I'm going hose hunting locally.

Has anyone else experienced this problem? (I've even considered lopping off the protruding cast iron boss,but that doesn't seem like a tidy solution . . . even though I can see no need for the offending lump.)

I've attached a cell-phone photo taken beneath my car: the circular thing is the 2" diameter opening for the cooling hose. Note the cast iron piece of engine block that presses directly against it.

MarkPan

I seem to think that even with the stock alt, the belt is too bloody short. Maybe I'm thinking of the compressor, though.

I can't see going a size up hurting anything?

audi_marv

I think the belt you have is for 90 amp alternators, and with the 110 amp alternator being larger, may require a longer belt ?

Thought i read somewhere that there are two alternator belt sizes. One for cars with A/C, and one without (or am i thinking of the power steering belt ?).

Wouldn't be the first time a parts store got it wrong either.

Randolph

I'm using the 11.2 X 820 with no problems but I have the 90amp unit. Is it possible that the 110amp uses a different rear cover to accept the cooling hose and your not using the correct cover? I seem to recall those covers only going on one way but having said that, maybe it's possible to "rotate" that cover one stud counter clockwise (when looking at the back of the alt)to allow more room.

R

RussB

That's a clever idea, but I'm sure that the cover is indexed correctly. Today I located a 11.2 x 866mm COntitech be4kt, so I'll (try to) install it tomorrow.

I think that the 110Amp alternator body is a little larger diameter than the 90 Amp alternator body.

RussB

Update: An 11.2 mm x 866 mm drive belt is too long. The alternator is now at the end of its adjustment range, and there's about a 1 inch gap between the cooling hose input and the engine block "lug". The belt isn't as tight as it should be, either.

I need a 11.2 mm wide belt that's about 830 to 850 mm long.

RussB

Update 2: It being Sunday, my selection of v-belt vendors was limited. I bought a GoodYear "Gatorback" 15332, 11AV0825. It's a bit wider than 11.2 mm, and about 3/4 inch longer than 820 mm. It rides about 1/32 inch high in its pulleys, which I'm not pleased about, but it is working and has given me clearance to attach the alternator cooling hose. (It's red because it's a 2 inch diameter 1 foot long silicone "SCAT" hose from the world of aircraft.)