OM603 fan + clutch upgrade. 1987 300D - Page 5 - PeachParts Mercedes-Benz Forum

gsxr · #61 07-03-2008, 08:38 PM

LOL, Jeremy, I thought maybe you learned your lesson after the vacuum pump incident...

HMX, where did you buy your "Behr" from (which I presume is an offshore knockoff?)

Hit Man X · #62 07-03-2008, 08:39 PM

Quote:

Originally Posted by gsxr

LOL, Jeremy, I thought maybe you learned your lesson after the vacuum pump incident...

HMX, where did you buy your "Behr" from (which I presume is an offshore knockoff?)

Interamerican Motor Corporation, my supplier.

They also carry a Sachs and Meyle, I suppose they'll take the Behr back. I'd drop the cash for the Sachs.

Jeremy5848 · #63 07-09-2008, 04:13 PM

Quote:

Originally Posted by gsxr

LOL, Jeremy, I thought maybe you learned your lesson after the vacuum pump incident...

Some of us never learn!!!

BTW, I now have both fans with their clutches out and on the bench and it appears that the fans and clutches are completely interchangeable -- either one fits the other. I know that the 603 clutch is NLA so you have to buy a 606 clutch but I though you had to buy a 606 plastic fan because the 603 fan wouldn't fit the 606 clutch. Did I misunderstand? This is just a curiosity -- I still plan to install the new clutch and the new plastic fan.

My 603 was abused as a child, maybe it has the wrong parts? No, it has the right parts per EPC
Fan 116 205 24 06
Clutch 603 200 04 22

I can certainly under stand the advantages of the lighter plastic fan -- less rotating mass --
603 fan + clutch = about 4 pounds
606 fan + clutch = about 3-1/4 pounds
but if your 603 clutch is still good, why not just install the lighter plastic fan and keep the clutch? And if your 603 clutch fails, why not replace it with a 606 clutch and keep your 603 fan if you don't want to "upgrade" to the 606 plastic fan?

BTW, my cheapo clutch did come with a sticker on the box, part number 603 200 00 22 and "www.uroparts.com." Their company name appears to be "Uro Parts" with an umlaut over the "U" so the pronunciation is very much like "Euro parts" which I'm sure they had in mind.

The website says that "Uro Parts" is a division of A.P.A. Industries, "created to provide a better choice to the European replacement parts industry." They have design and manufacturing facilities in 9 countries including the US, Italy, Spain, Taiwan, China, Korea, Thailand, Israel and Brazil. So it may not be a garbage part after all. Two year warranty, they say -- but working through the eBay seller is another question. We'll see what happens once I have the new parts installed.

Jeremy

gsxr · #64 07-09-2008, 04:55 PM

The EPC is what indicated the early & late fan blades are supposed to only be used with their respective early/late clutches. But we don't know why MB specified that. If they physically interchange, and the dimensions are all the same, the hybrids might work fine. The hard part is properly diagnosing if the clutch is bad (unless the center bearing is shot, which is relatively easy to determine.)

Hit Man X · #65 07-09-2008, 06:56 PM

I used an M103 clutch with a 606 fan blade before I knew the 606 clutch itself was cheap...

babymog · #66 07-09-2008, 08:28 PM

The clutch limits maximum RPM. The two clutches and fans might have different max. RPMs to accomodate the material's safe limits.

Hit Man X · #67 07-09-2008, 08:39 PM

Well my M110 has a plastic fan... motor is good to big RPM (6500+)...

babymog · #68 07-09-2008, 08:46 PM

Okay, but the clutch does not spin full RPM, it starts to slip as RPMs increase. This is why some BMWs grenade the fan when the clutch goes bad, over-speed. Read the manual on the 60x engines, the fan will only spin up to a pre-set maximum RPM which is less than the engine's max. This way it can be designed to move air efficiently at lower engine RPMS without being too much of a hp hog at higher RPM.

The plastic fan will also flex outward and forward depending on load and RPM, that can also be a problem if not limited.

Hit Man X · #69 07-09-2008, 08:49 PM

Quote:

Originally Posted by babymog

Okay, but the clutch does not spin full RPM, it starts to slip as RPMs increase. This is why some BMWs grenade the fan when the clutch goes bad, over-speed. Read the manual on the 60x engines, the fan will only spin up to a pre-set maximum RPM which is less than the engine's max. This way it can be designed to move air efficiently at lower engine RPMS without being too much of an hp hog at higher RPM.

So what's your point in regards to this? If it works, run it.

I've had the 103 clutch and 606 fan for years before I got the 300SEL... I put the proper clutch on the 300SEL and a 606 clutch on the SDL. No issues.

85chedeng300D · #70 07-09-2008, 08:54 PM

Quote:

Originally Posted by Hit Man X

Well my M110 has a plastic fan... motor is good to big RPM (6500+)...

...but isn't it that the actual engine RPM may be slower than the RPM of the fan clutch pulley.....if the pulley of the fan clutch is way smaller than the crancshaft pully, the fan will spin faster.....?

Hit Man X · #71 07-09-2008, 08:56 PM

Quote:

Originally Posted by 85chedeng300D

...but isn't it that the actual engine RPM may be slower than the RPM of the fan clutch pulley.....if the pulley of the fan clutch is way smaller than the crancshaft pully, the fan will spin faster.....?

Yes, engine RPM.

I'd have to measure both for you, it's too hot. My 745i BMWs have SMALLER water pump (fan) pulleys than crank, the fans have not exploded into bits either.

85chedeng300D · #72 07-09-2008, 09:03 PM

Quote:

Originally Posted by Hit Man X

Yes, engine RPM.

I'd have to measure both for you, it's too hot. My 745i BMWs have SMALLER water pump (fan) pulleys than crank, the fans have not exploded into bits either.

...so, the fan clutch speed rating is based on the water pump speed and not the engine speed which the difference depends on the pulley diameter...

As for your BMW, if the fan clutch is stock, it is pro'ly rated for higher speeds and actually designed for the ratio of pulleys between the crank and the fan clutch...

Hit Man X · #73 07-09-2008, 09:07 PM

Quote:

Originally Posted by 85chedeng300D

...so, the fan clutch speed rating is based on the water pump speed and not the engine speed which the difference depends on the pulley diameter...

As for your BMW, if the fan clutch is stock, it is pro'ly rated for higher speeds and actually designed for the ratio of pulleys between the crank and the fan clutch...

So it's rated for even higher RPM than engine speed. Again, just run it. You will have no issues.

Actually the 745i twins have US 733i clutches but Saharan climate crank + water pump pulleys. It's a mix of parts too.

85chedeng300D · #74 07-09-2008, 09:20 PM

Quote:

Originally Posted by Hit Man X

So it's rated for even higher RPM than engine speed. Again, just run it. You will have no issues.

Actually the 745i twins have US 733i clutches but Saharan climate crank + water pump pulleys. It's a mix of parts too.

Reason I ask is: I have an '85 300D Turbo with 617.952 and wishing that I can have it to have an improve airflow, I swapped the water pump pulley with a smaller diameter pulley from 500SEL but the clutch is slipping at 3000 engine RPM and the air flow across the radiator isn't moving anymore, so I have to switch back to the stock pulley and belt size.

Hit Man X · #75 07-09-2008, 09:23 PM

Quote:

Originally Posted by 85chedeng300D

Reason I ask is: I have an '85 300D Turbo with 617.952 and wishing that I can have it to have an improve airflow, I swapped the water pump pulley with a smaller diameter pulley from 500SEL but the clutch is slipping at 3000 engine RPM and the air flow across the radiator isn't moving anymore, so I have to switch back to the stock pulley and belt size.

I was under the impression all the late 617s got the M110 plastic fan, fan clutch, and smaller water pump pulley?

Mine does at least, I doubt it was updated due to the PO's. I'm working on an '82 for someone that has the large water pump pulley and steel fan.

3K RPM should be 60+ MPH in top gear Are you having cooling issues?