190E - oil pressure problem and running high temp prob - PeachParts Mercedes-Benz Forum

Joseph_190E · #1 10-25-2005, 12:27 AM

I have several problems which may or may not be related.

First I have a 1992 190E with 208K miles and I am using a 20-50W oil.

1. Oil pressure gauges shows ZERO on idle. The benz runs fine. When I accelerate, it goes to 3. I wonder if the oil pressure sending unit is the cause? What do you think?

2. My benz seems go to high temps quickly. From a cold start then drive for 10minutes the temp goes to 100 deg. When I drive on the freeway, no traffic and going 65mph, temp is about 98/99. I expect it to be 90-94.

Also, my fans (dual smaller fans) don't engage at 100. It use to engage at 100. Now it engages at 110.

I did change a sensor related to my fan being constantly on. That fixed the problem way back (about a year ago).

t walgamuth · #2 10-25-2005, 08:33 AM

you checked and cleaned the contacts on the op sending unit? on the heat, the usual drill: clean radiator fins, check thermostat, flush cooling system, change water pump, change radiator, in order of cost.

a little more info on the way it is getting warm might help us zero in.

tom w

yal · #3 10-25-2005, 08:55 AM

The heating problem is most likely your thermostat.
The fan(s) in front of the radiator will not come on until 105-110 or with high a/c pressure.
Do you have a 2.3 0r 2.6?
If you have a 2.3 the main fan locks at 100-105c. It spins freely until then.
If you have a 2.6 its a viscous fan which spins faster the hotter it is. Wait till the car gets hot, turn the car off and try spinning the fan, it should have some resistance.

The oil pressure is a little worrying. I would change the sending unit.

mike2005 · #4 10-25-2005, 09:20 AM

Have you recently changed to the 20w-50 oil, or have you been running this oil for quite some time? Difference in oil visocity will change operating temperature.

masonn300 · #5 10-25-2005, 08:32 PM

i had the same problem with my oil presure that you are having. not sure what kind of oil filter you are using but i found out that it was the oil filter on my car. i did a search on the forum and found that could be one of the problems so i took my car to a mb dealership and did a oil and filter change and now oil presure solved.

good luck

Joseph_190E · #6 10-26-2005, 06:59 PM

Quote:

Originally Posted by t walgamuth

you checked and cleaned the contacts on the op sending unit? on the heat, the usual drill: clean radiator fins, check thermostat, flush cooling system, change water pump, change radiator, in order of cost.

a little more info on the way it is getting warm might help us zero in.

tom w

How do I clean the op contacts and with what?

Joseph

blackmercedes · #7 10-27-2005, 09:29 AM

Our now-sold 190E had the exact same oil pressure "problem." It would read zero at idle (yikes!) but hit 3.0 as soon as you got the rpms up a bit. It was thge sending unit, and that is a common way that they fail.

We also had that warmer-then-normal problem. Turned out (after hard work goign through the cooling system) that the rad was blocked from years of crap banging into it. Unfortunately, the 2.6's rad is tough to remove, but we did and cleared it out. Problem solved.

Joseph_190E · #8 10-29-2005, 02:32 AM

Quote:

Originally Posted by blackmercedes

Our now-sold 190E had the exact same oil pressure "problem." It would read zero at idle (yikes!) but hit 3.0 as soon as you got the rpms up a bit. It was thge sending unit, and that is a common way that they fail.

We also had that warmer-then-normal problem. Turned out (after hard work goign through the cooling system) that the rad was blocked from years of crap banging into it. Unfortunately, the 2.6's rad is tough to remove, but we did and cleared it out. Problem solved.

This might be my problem. I'll try to get a radiator flush right away. As far as my oil pressure, I think it is the sending unit and nothing else. Why? Because my car runs fine and I've been driving for a week. If zero oil pressure, my car wouldn't be running this good. Am I right?

Well, I haven't heard any opinions on why the fan isn't engaging? I know it is probably one of the sensors. But which one? The fan usually engages at 100C.

thanks
joseph

Joseph_190E · #9 10-29-2005, 02:33 AM

Anyone know of a good radiator place that is cheap, does a good job and won't rip you off?
I am located in Southern Cali. (South Bay area)

J

mykg4orce · #10 10-29-2005, 03:40 AM

Check your fan clutch, and fan clutch bearing bracket. The fan clutch must tighten up when the temps are high. If your fan spins freely at high temps....your fan clutch is in need of replacement. If you have the original radiator, get a new one. A new rad and new fan clutch solved my overheating problems for good.