190 E overheating

[smallcowsheep]

I am writing on behalf of my son, who's at work. He has literally just bought a 1991 190E and it is overheating. My husband has backflushed rad. checked thermostat, fan etc. It has brand new water pump so I would say this was a known prob. Due to absence of oil in water (mayonnaise etc) we don't think it is head gasket and anyway, the engine is running sweet as a nut.

We are a family for whom the words "old" and "car" are one and the same thing so are not too afraid to get our hands dirty (though I do hate chipping my nail varnish and spanner rash is a real bugger).

Any further thoughts would be most gratefully accepted. Oh, there was lots of crud in the radiator but he has given it a run since and overheating (or rather, running hot as my husband has just said) is still happening.

 

[vijilants]

If there was loads of crud coming out of the radiator, chances are that the radiator is blocked up and beyond use.

Suggest you try a new rad and thermostat, if the fan is working ok.

 

[neilrr]

Hi,

What engine is in it? How hot is it running? Where on the temp gauge is the needle?

 

[Sp!ke]

Did he correctly burp the coolent system after flushing it?

 

[recycled]

check if the rad is hot from top to bottom as you may have an air lock in the system. or try running it with the cap off for a few minutes

 

[grober]

HEAD GASKET is a very common problem on these so I wouldn't rule it out. If your son has just bought it maybe the seller did a quick coolant and oil change prior to the sale?? Things would look OK for a short time till the fluids got contaminated----?? Best test is exhaust gas from the coolant reservoir or a cylinder compression test

 

[smallcowsheep]

Oh guys, thank you so much for all your feedback. My son is a greenhorn in the vehicle stakes and is much cast down by what he fears is a bad buy! In answer to your various kind queries. Yup, could be the rad is totally u.s., seller has offered new one if needed. Car has 1800 engine with no AC on it. No, husband hasn't "burped" it. So sorry, but has anyone the patience to tell us how to do that? It is currently running between 90 and 100 degrees. We will bear in mind the gasket possibility but suffice it so say, the car was sold to him by a guy who is a friend of a colleague of my son's who really looks out for him so I think the chances of him having been stitched up are small.

Phew! Really do appreciate all your input

 

[bigtee]

Try a new thermostat for the price of a few quid first & bleed the system.

The heater matrix could also be blocked it's worth giving that a back flush too & prevent any air locks.

If that rad is full of crud just replace or have a new core fitted to the existing unit, but as said don't rule out the head gasket a sniff test is a good idea, the kit is available to buy on e bay £30.00 may come in again.. good luck..

 

[grober]

Burping is achieved by squeezing the radiator hoses ( engine warmed up with the cap off) to break any airlocks. Try to get the car positioned ( on ramps or a slope) so that the radiator/coolant reservoir is the highest point in the coolant circuit. Depending on where the car was being driven--in traffic --the electromagnetic fan coupling may not be working. You should hear it cutting in as the temperature rises-this should not happen on the open road as airflow thro the radiator should normally keep the temperature down.

 

[Sp!ke]

Do the above with the interior heater controlls on hot.

 

[neilrr]

Where are you based?

 

[smallcowsheep]

Right. Great stuff. Things are looking up. Thanks again for all help. We're based in deepest Maidstone where men are men and cars are rusty - well, ours are.

 

[recycled]

make sure the heater is on full and the heating controls are on red while doing this

 

[smallcowsheep]

Just wanted to say a final thank you to all you helpful people. Thanks to your input the overheating problem is now cured and my son is very happy with his new car. Long live mercs!