Mecedes 420sel lower water pump bolt - Auto-Trend Repairs and Service Information Forums

gluvich · Rookie

Mecedes 420sel lower water pump bolt

SELLC · CERTIFIED POST WHORE

When trying to gain access to the lower water pump bolt thru one of the two notches for the front crank position sensor you would need a 1/4 inch drive Universal with a 1/4 inch drive universal short extension. Even then once its broken free its a finger tips removal process. When cheating thru the notch for the CPS I am usually just busting down a core engine where as I dont plan on re-installing. I am not sure if that bolt will even come all the way out on a 420 without removing the lower pully.

If all else fails you will need to remove the six 13mm bolts holding on the lower crank pully. When replacing a pump I will remove the balancer and also the crank pully to ensure a clean surface and a proper torque.

Have you got the bolt loose?

-- Edited by SELLC on Friday 30th of July 2010 08:58:14 PM

SELLC · CERTIFIED POST WHORE

You can also check out this thread here.

http://autotrend.activeboard.com/forum.spark?aBID=91042&p=3&topicID=11043296

Sometimes you dont even need to remove the big 27mm bolt, however on others the washers were so welted up with rust I have. Just be careful not to bend the lower pully as it will wobble.

If a rubber mallet or a little pry bar wont pop the lower pully after you remove the smaller bolts, then I would zap the 27mm bolt. If you dont have a impact, buy some penitrating oil and let it sit overnight on the area.

-- Edited by SELLC on Tuesday 15th of June 2010 11:26:53 PM

gluvich · Rookie

thank you

gluvich · Rookie

thank you

SELLC · CERTIFIED POST WHORE

Hey no problem, hope it helped. Did everything work out?

gluvich · Rookie

I put the pump on. Do you know what torque I can tighten the bolts
thank you

SELLC · CERTIFIED POST WHORE

The torque specs should come with the instructions. The last few I did come with them. Having always used the ones supplied, I never noticed that Mitchells on Demand does not have the torqe spec for the water pump!

I can not recall the exact lbs it was, Mercedes pumps are one of a few that come with the torque specs. 25-30 Ft Lbs I am guessing, but it's been awhile. It's not like everyone is driving a W126 S-class now days.

Main part is to have it clean-clean-clean. And also nice even tightness.

That big 27mm bolt is 400 Nm and amazingly enough the smaller ones that hold the balancer are 35Nm.

If you purchased a new pump there should be a sheet in the pump with the torque specs. I am thinking it will also read in Nm.