I am having just the worst luck with parts lately. The belt tensioner I bought a year ago and now installing turns out to be defective. Looks brand new but grab the flat bushing and you can spin it either way with no tension at all. The shop is selling me a new one for cost, about $50. So I'm checking out all the pulleys and I find I need 1) Idler pulley. Still smooth but spins forever with a high pitch squeal so no grease left at all, 2) New rebuilt smog pump and pulley. The pulley was not so bad but the bearings in the pump were grating, and 3) Fan bracket. The bearing is notchy and grease is leaking out the back of the bearing. So I get the new bracket and put it in while I wait for the new tensioner. There are 7 bolt holes in the bracket. Two are tapped for the idler pulley and the bolt that holds the heater return line. The upper right hole and the 2 in the center are the small holes. The upper left (to secure the smog pump) and the lower right (for the "wet" belt tensioner bolt) are slightly larger. I confirmed this with the old bracket. But in the new bracket the lower right hole is too small for the tensioner bracket bolt!!!! This hole is the same size as the three smaller holes!! Part numbers are the same for both. It seems there was an error in manufacture. Anyone else ever have this problem?

glenmore
1991 300CE
2000 C280
1990 LS400

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I'm not sure I understand your bolt problem but your tentioner problem makes me ask the question: do you know the difference between a $10,000 Rolex watch and one sold for $25 on the street? Fifty dollar tentioners remind me of which one?

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Steve,

The lower right hole in the new fan bracket is too small to let the tensioner bracket bolt thru. The photo of the new bracket shows this bolt sitting there, uable to be threaded and the photo of the old bracket shows this bolt dropping thru so it can be tightened.

Yes, the price of the tensioner is quite low, but it is what he said, "his cost". I originally paid $93 for the one that turned out to be defective, so I'm just trying to salvage that transaction. I assume that these are just tensioners he sells to everyone else and I've just ended up paying $93 + $50 for one.

Thanks,

glenmore
1991 300CE
2000 C280
1990 LS400

The bolt obviously has a shoulder on it. I don't do disassembly work (at least not in the last 15-20 years) so I'm not familiar with what the shoulder is for. I would guess that the shoulder should be for the pully or some other part that would have it outside the hole. If it needed to pass through the hole the options would be to drill it or return it for a proper part. What I do know about is that real MB parts with the same numbers are not likely to have ths difference.

My point about knowing the difference between watches was that although they look the same there is an issue of quality involved. There are decent aftermarket tentioners, none are as cheap as 50 dollars cost. So the point is do you get a deal paying 93 for one that doesn't work plus another 50 for a similar one that has yet to fail. A good tentioner is a POS and MB went away from that design. A cheap imitation of a POS design probably will keep you busy.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician