water pump and thermostat torque specs
Thread Starter
Super Member
Joined: Dec 2002
Posts: 560
Likes: 1
From: FL
2000 S500 Brilliant Silver, 1990 BMW 735iL, 1971 Pontiac Trans Am 455 HO, 1976 Pontiac Formula 400
water pump and thermostat torque specs
Hi-
My weekend project is to replace these. Can anyone provide the torque specs?
Also, how do you flush the cooling system?
Thanks!
My weekend project is to replace these. Can anyone provide the torque specs?
Also, how do you flush the cooling system?
Thanks!
Thread Starter
Super Member
Joined: Dec 2002
Posts: 560
Likes: 1
From: FL
2000 S500 Brilliant Silver, 1990 BMW 735iL, 1971 Pontiac Trans Am 455 HO, 1976 Pontiac Formula 400
cooling system quandry
My 2000 S500 has approx. 165k miles on it and one day last week started running hot , fairly close to redline. I ran it home on the highway, hoping the airflow would cool it down, but it did not.
Checked coolant, fan and oil level. All are fine.
So I bought a water pump. thermostat and coolant. Today, I am flushing the coolant and while running the car with less coolant in each flush cycle, the car won't run hot any more.
I took it fore a 10-15 minute drive after several flush cycles now basically pure water and it still didn't go over 90C.
Now, I am not sure I should bother with the hassle and expense of installing the water pump if it is not needed. Maybe just install new thermostat and coolant.
Any ideas what is going on with the cooling system? The coolant I removed did not look bad or cruddy at all.
Thanks!
Checked coolant, fan and oil level. All are fine.
So I bought a water pump. thermostat and coolant. Today, I am flushing the coolant and while running the car with less coolant in each flush cycle, the car won't run hot any more.
I took it fore a 10-15 minute drive after several flush cycles now basically pure water and it still didn't go over 90C.
Now, I am not sure I should bother with the hassle and expense of installing the water pump if it is not needed. Maybe just install new thermostat and coolant.
Any ideas what is going on with the cooling system? The coolant I removed did not look bad or cruddy at all.
Thanks!
Senior Member
Joined: Apr 2012
Posts: 432
Likes: 96
From: Just north of Detroit,Michigan
2012 E350 4Matic P2
Thanks, Bob!
I would finish the plain water flushing then get the system back to 50/50 antifreeze level and make sure that you are really full. Drive the car for a few days and see if it continues to overheat. If it stays running cool then you are done for now. You can change out the thermostat as that is a failure item but when they fail, they are designed to fail in the open position although anything is possible. As to the water pump, it either works or it doesn't. Most usually they begin to leak around the front bearing or the bearing itself fails then seizes.
I changed out my thermostat because I was having the opposite problem to yours, my car was not warming up enough and was setting a CEL p0115, My story here.
Good Luck, Bob
Thread Starter
Super Member
Joined: Dec 2002
Posts: 560
Likes: 1
From: FL
2000 S500 Brilliant Silver, 1990 BMW 735iL, 1971 Pontiac Trans Am 455 HO, 1976 Pontiac Formula 400
Thanks. That is a great write up.
Do you have any tips on making sure the cooling system is full? I have heard about the difficulty in getting air out but not sure how.
Do you have any tips on making sure the cooling system is full? I have heard about the difficulty in getting air out but not sure how.
Senior Member
Joined: Apr 2012
Posts: 432
Likes: 96
From: Just north of Detroit,Michigan
2012 E350 4Matic P2
No tips to share except to keep checking the level often. As an aside, I see from your signature that you have a 735il. I had a '91 750il before purchasing my Merc. I accumulated many tools due to that ownership! 
In my opinion, Apples to Oranges comparison Bimmer to Merc. Each has it's pleasures.
Good luck, Bob
In my opinion, Apples to Oranges comparison Bimmer to Merc. Each has it's pleasures.
Good luck, Bob
Trending Topics
Thread Starter
Super Member
Joined: Dec 2002
Posts: 560
Likes: 1
From: FL
2000 S500 Brilliant Silver, 1990 BMW 735iL, 1971 Pontiac Trans Am 455 HO, 1976 Pontiac Formula 400
Yes, I need to update my profile. The Bimmer is gone. I gave it to my daughter during high school.. and it went down hill quickly.
That car did absorb a lot more of my money over the years than the Benz, but it did handle much better. I had a 533i stick before that, which was a great car.
I see your from MI north of Detroit. I'm from Flint- a great place to be from. I have friends in Holly and Lake Fenton.
That car did absorb a lot more of my money over the years than the Benz, but it did handle much better. I had a 533i stick before that, which was a great car.
I see your from MI north of Detroit. I'm from Flint- a great place to be from. I have friends in Holly and Lake Fenton.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
