OM603 Belt Tensioner Lever Option - PeachParts Mercedes-Benz Forum

nelman · #1 02-04-2015, 02:13 AM

My car is an 87 300sdl with an OM603.

I'm having a hard time looking for a replacement belt tensioner in my country - Part No. 601-200-17-73.

Has anyone tried using the om606 tensioner (606 part no.) for the om603 engine?

The 606 tensioners are easier to come by in this part of the world since a lot of them were used in the MB100/Ssayong Istana (Asia Pacific) with om602 engines.

Any input is appreciated. TIA

nelman · #2 02-07-2015, 04:59 PM

anyone?

Jeremy5848 · #3 02-07-2015, 05:07 PM

I've never compared the two side by side but they certainly are similar--worth an experiment.

dieseldiehard · #4 02-07-2015, 05:49 PM

Quote:

Originally Posted by nelman

My car is an 87 300sdl with an OM603.
I'm having a hard time looking for a replacement belt tensioner in my country - Part No. 601-200-17-73.
Has anyone tried using the om606 tensioner (606 part no.) for the om603 engine?
The 606 tensioners are easier to come by in this part of the world since a lot of them were used in the MB100/Ssayong Istana (Asia Pacific) with om602 engines.
Any input is appreciated. TIA

My '87 uses the 601-200-1773. Left photo.

I pulled a photo of the 606-200-0173 (right photo) and it looks different in the area or type of bearing.

Maybe cost reduction? If you post a want on the parts section its quite likely a member will have one thats in good shape and surely cheaper than whatever a new one will cost you there. Here a new 606 tensioner is over $115. Never replaced the one on my 606 but have replaced the tensioner on my 603 engine when I rebuilt it maybe 6 years ago and its still ok (knock on wood). Its the pulleys that seem to fail most often.
DDH

nelman · #5 02-11-2015, 04:32 AM

Thanks for your replies.

Another option is to bring it to a machine shop and have the bearings replaced? or is that even possible?

From the outside, it seems that there are 2 bearings inside the belt tensioner housing itself, and one side as a snap ring holding them.

Jeremy5848 · #6 02-11-2015, 10:28 AM

It should be possible to press out old bearings and install new ones. The 606 uses a plain bearing. You would have to exchange the entire assembly, if it would even fit. Probably easier to replace the bearings.

ah-kay · #7 02-11-2015, 10:30 AM

It is very doable just to replace the bearing. I have done it. The original bearing is double width. I replace it with 2 single width bearings as the double width may not be readily available. The bearing is 6004-2RS. You need 2.

Remove the snap ring, very stiff. Heat up the outer casing and hammer it out. Heat up the same when you put the new one back in. Measure the width of the old bearing and the 2 new bearings first. They are not exactly the same so you have to leave a gap between the 2 new bearings. I have it running in my 87 300D for over 15K miles now without problem. Bearing is about $2 each. The tensioner is as good as new. Cheaper if buy bearing in quantity. They are very common type.

btw: you may need to sand down the bolt as it may be difficult to press into the center of the bearing.

Good luck.

nelman · #8 02-12-2015, 04:00 PM

Thanks for the info.

Quote:

Originally Posted by ah-kay

Measure the width of the old bearing and the 2 new bearings first. They are not exactly the same so you have to leave a gap between the 2 new bearings.

do you mean there should be a gap between the (new) bearings in terms of their position along the axis of the bolt?

If I understand correctly, I just need to space them so that the width is the same as the double width original, right?

ah-kay · #9 02-12-2015, 04:10 PM

You can leave a gap or put a big washer in there. It has a big tolerance.

jbach36 · #10 02-12-2015, 08:54 PM

No sense experimenting with the wrong part.

nelman · #11 02-14-2015, 09:44 AM

I used the correct 603 tensioner, I was able to replace the wide bearing with two 6004 (12mm) bearings and a 5mm washer between them. I did not sand down the bolt, the hydraulic press took care of it.

Haven't had time to install it but I'll get back with the result soon.

vstech · #12 02-14-2015, 11:10 AM

Did you take any pictures?

I'd think you could simply press the first one in place, then press the second one in until it clears the snap ring... A washer may not be needed.

ah-kay · #13 02-14-2015, 11:26 AM

Quote:

Originally Posted by nelman

I used the correct 603 tensioner, I was able to replace the wide bearing with two 6004 (12mm) bearings and a 5mm washer between them. I did not sand down the bolt, the hydraulic press took care of it.

Haven't had time to install it but I'll get back with the result soon.

Good job. Glad to help you with the info. It should be as good as new. I do not have a press as I am a DIY, so I heat it up.

ah-kay · #14 02-14-2015, 11:28 AM

Quote:

Originally Posted by vstech

I'd think you could simply press the first one in place, then press the second one in until it clears the snap ring... A washer may not be needed.

NO. You need a washer when use with a press. You have to press in the center bolt FIRST.

nelman · #15 02-15-2015, 02:52 AM

Quote:

Originally Posted by ah-kay

NO. You need a washer when use with a press. You have to press in the center bolt FIRST.

+1 on that. I couldn't think of a way to hold the bearings in place along the axis of the bolt while pressing into the housing.

Sorry I wasn't able to take pictures. I was pressed for time since the car is my daily driver. I'd be glad to draw a diagram if anyone needs it.

I've installed it today, everything's now smooth in the belt area except for a slight vibration from the small shock, I just realized the lower bushing was shot and couldn't wait for a new part. At least the idler pulley is now aligned with the rest.

Thanks for the info ah-kay, now I'm off to r&r the other tensioner I have in case I need another one in the future - maybe after 15k miles?