Water pump replacement

[kampala]

The 250sl water pump sprung a leak.  Decided to install the longer pump with shorter bolts.   (I asked our forum member Tyler for advice as the many posts I read gave partial info, Thanks Tyler!)

Got shorter bolts from clipsandfasteners.com   


It’s a lot of work to get to the pump.   Maybe the pros can do it without removing as much as I needed to.

Remove hood
Remove radiator shroud
Remove battery
Remove air filter housing
Remove radiator
Remove fan/pulley
Loosen alternator
Remove water pump
Remove bypass pipe with hollow bolts.

Scrape gasket, scrape gasket, scrape gasket - had to scrape carefully so not to gouge the housing.

Install - reverse of removal 
Used thread sealant as some bolts go all the way through. 

A photo of short bolts installed on fan included. 

[ja17]

Yes much easier with the long pump and I believe it to be a more durable configuration.

[WRe]

Hi,
some years ago I was just about to install a new viscous coupling and anyone who knows the subject knows that you can throw away the 4 screws (collar screws M8x16, WS10) that hold the fan on the water pump afterwards because the hexagon is turned round. Those in the know will know why.
Well, I thought, just get some new ones. Think, because M8 screws usually have SW13 and those with SW10 are almost impossible to find, especially not around the corner. So on to, as he is always called here, friendly. But he wasn't all that friendly and had a hard time finding these screws, apart from the fact that they weren't in stock anyway and, if they were the right ones, they should have a steep price, at which you can would get at least 30 of them elsewhere. Currently more than 7 euros, ten times more then the price you paid.
Aslam next time you come to Europe or Germany you should bring some packages with you. :-)
... Wolfgang

[dirkbalter]

Interesting, my water pump (long) came with m8 threaded studs. That allowed me to use regular sw13 nuts to bolt the clutch to the waterpump. Mounting was relatively uneventful. What’s the reason to use small head bolts versus regular ones?


BTW, I believe a lot of Japanese motorcycles use “small head bolts” .
https://specbolt.com/nickel-wurks-bolts-2/?sort=alphaasc&page=2

[WRe]

I use sw/ws13 screws too, is a little more fumbling and maybe a little more moving mass.

[kampala]

Interesting, my water pump (long) came with m8 threaded studs. 2

I went back and looked in the box -  I had ordered a few parts together -- and I just found 4 studs in a small baggie!   Had read so much about using 10mm head short bolts that I didn't even notice the studs.   I did not think there was room for larger heads.