David C

We have a 180e with 115,000kms that will run perfectly at 80' in either city or highway driving, then the gauge will flatline at 120'+ for 5-10 mins either on the freeway or suburban streets & then will resettle back at 80'.
Its intermittent, irregular & very frustrating. after trying everything, stopping till it cools, replacing the Temp sensor in the head, replacing the thermostat, had the radiator thoroughly cleaned with top & bottom tanks removed. etc - nothing has worked.
Shortly after purchase, it it blew a water hose once, next it blew through the radiator cap and then finally following a 25k drive & finishing the drive, the engine temp spiked and blew out the top plastic header tank needing replacement. None of the above was aggressive driving, - all soft pedal stuff.
Is it the gauge, the water pump, the way I talk to it ???
BTW All of the above without any protest or change in engine behaviour or performance, - it works fine, no lumpy hesitation, smells, loss of water etc
Anyone, any clues ? Cheers dc

Rauhbatz

Hi David...my 1991 190E used to run a bit like that...especially sitting parked in traffic. Sounds to me like the water pump is starting to go. The spiking is similar to when my first water pump let go at just over 100,000 mi...had it also start to fail at 200,000 miles...so it looks like they last 100K miles.

I would wager that the pump is stating to fail internally...likely time for a replacement

David C

Hi Rauhbatz, many thanks for your response, I am coming to the same conclusion, as with the exception of taking off the cylinder head, the water pump is the only remaining auxiliary piece that I have not tried. I have changed both sensors at the front of the head & the radiator is new (following a bloke reversing in to me 3 weeks ago - Aaaargh !) but the fluctuations still remain.
I will change it as it will be summer here in Australia in 3-4 months & the temp can get to 38'+. I appreciate your help. my regards David

Rauhbatz

They seem to last about 100K miles...so yours is likley at fault. Make sure your mechanic also changes the new thermostat just in case...and also replace the radiator cap as mine was original; looked great but didn't work that well...a Honda Accord cap fit perfectly.

My 190 still heats up to 100F when sitting for a while. Im guessing since it has the original radiator that is likely my weak spot. I flush it once a year which helps a little bit but I think it is a victim of age.

The 190 makes for a great airport car as I travel every week; can't seem to rationalize getting a new set of wheels just to take it to the airport and back. At the early times in the morning when I leave there is little chance chance for overheating, even in this heat wave!

KK

David C

Hi KK, Ours heats up to 120' & sometimes sits there for 10 mins, & will then fall back to 80'. Othertimes will momentarily spike to 120 for 1 min & then back to 80'.

Will get the Pump replaced.

This is such a sweet AND safe car, that I simply want it to be good for all uses. Cheers David

PelicanParts.com

I agree.
I have the W201 190D with 420000 miles on it.
Between 80000 and 100000 miles it requires a new water pump.

roy@pelicanparts.com


.

David C

G'day Roy,
Thanks for your confirmation, will get on & replace the water pump.

BTW I searched your site under Water Pumps & Hoses to see price & availability but could not find any actual water pumps. Can you advise ?
I purchase quite a few bits from the US for my MGB & would be keen to know what your price for the Water pump would be, as the prices are generally better that the local guys.

Cheers
David

David C

Hi All,
I have just replaced the Water pump, - still the Temp gauge goes to 120' - btw the old one looked in very good health. Is there any history of the gauge being faulty on the 180e/190e ???
My next step is a compression test to see if there is a head gasket issue, if not surely it can only be the gauge as I have replaced the sensor on the head and the engine shows no sign of overheating, - no run on, no loss of power etc.

Any clues, next steps, ideas ??? - pls advise. signed bemused. (David)