2.5 turbo water pump pulley It's smaller it rotates the water pump faster it's gotta be an improvement on the cooling system

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Are you talking about using an OM602 water pump pulley on the OM603? How much smaller is it?
I test fitted an M103 fan belt pulley on the OM603 water pump. Its about 10% smaller in diameter, I just need to find the correct shorter belt.

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CENSORED due to not family friendly words

yes. the 602 wp pulley is about 20% smaller... I needed a longer belt for the alternator upgrade I did, and the smaller pulley fit the bill perfectly. and it gives the car better cooling!

this page http://www.peachparts.com/shopforum/diesel-discussion/147330-om603-serpentine-belt-routing.html#post3026888 shows the 602 belt size. however, I think the crank pulley is a different size as well.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

hmm - makes me want to buy one for my OM606 too, not that its overheating. Im also going to install a clutch pulley on my alternator too, it should help relieve the poor belt tensioner system from early failure.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)