Just bought my 3rd 89' W124... searching for 3 answers - PeachParts Mercedes-Benz Forum

macarose · #1 05-03-2006, 06:47 PM

This one is a 300 TE Wagon with approximately 155K on it. I am simply overjoyed to finally give my wife transportation that doesn't fit the 4000+ pound mode for her daily driving. Minivans are fine and all, but I'd really rather have both of us drive something that can fit in the our garage and, well, drives like a Mercedes.

I tend to be mechanically inclined but there are three things wrong on this one that may common to the lineage.

First we have the transmission shifting a little hard. The vehicle never shifts late and the transmission fluid is in good shape. I realize that their is a vaccum actuation system going on here but I honestly don't know how to track the problem down and replace what's needed. Any suggestions or thoughts? Even a link would help.

Second, the coolant temperature varies between 80 -99 degrees centigrade. I noticed a few things maintenance wise that may be related to this. The radiator, plugs and wires, alternator and battery all look to be new. I also found that the shop that reconditioned this car put in green fluid instead of the Zerex. I'm going to put in Zerex this weekend to remedy that. The cooling fan is coming on with a veangence but the opposite fan that is closest to the engine is rotating at what I would state as a 60% clip. Enough for their to be plenty of blur but not enough for me to think that it's doing it's job. When the vehicle is in park the temp will stay at around 85-90 but once you have stop n' go traffic the range increrases to about 20 degrees centigrade. Any ideas to track this down would be great.

Third, oil pressure is highly erratic on this one and I'm wondering whether it's a gauge problem or an oil pump problem. When I start up the vehicle the oil pressure gauge shoots well north of 3. If I drive on the highway for the first ten to fifteen minutes after it's fully warmed up it will stay at three but... once I start to do the stop n' go it will go down to 2 and sometimes to 1. It will go to 7/10's at idle but even if I rev it constantly it will go no higher than the 1.5 mark after about twenty minutes. I need to determine whether it's a fouled up gauge or whether something actually needs to be replaced on it.

I really look forward to making this car work. I've had two other 89's and gave them to enthusiasts, one of whom came nearly 2 hours to pick one up. I'm an auto auctioneer so the buying and selling of vehicles has always come naturally, and with it the tendency to work on them as well. To give you a grasp of how much I like this particular model, I am seriously considering selling a pristine Audi A8 because I find this wagon to be a more fun and durable piece of machinery. I'm also sending a 1996 E300 diesel to Florida and to be perfectly honest, I prefer driving the 89' model. The connection with the road and quality of workmanship in the W124 is two clicks above that particular generation. Thanks again for all your help and I hope all is well...

macarose

suginami · #2 05-03-2006, 08:15 PM

Sounds to me like your car is running in the proper temperature range.

I think your t-stat doesn't even begin to open until about 87 degrees, and then is not fully open until just above 100 degrees.

The fans you see turning are running in tandem at slow speed. They don't go on high speed until about 110 degrees. However, both should be turning at the same speed, either on high speed or low speed.

I also don't think there is anything wrong with your oil pressure or the guage.

BENZ-LGB · #3 05-03-2006, 10:48 PM

Quote:

Originally Posted by macarose

This one is a 300 TE Wagon with approximately 155K on it. I am simply overjoyed to finally give my wife transportation that doesn't fit the 4000+ pound mode for her daily driving. Minivans are fine and all, but I'd really rather have both of us drive something that can fit in the our garage and, well, drives like a Mercedes.

I tend to be mechanically inclined but there are three things wrong on this one that may common to the lineage.

First we have the transmission shifting a little hard. The vehicle never shifts late and the transmission fluid is in good shape. I realize that their is a vaccum actuation system going on here but I honestly don't know how to track the problem down and replace what's needed. Any suggestions or thoughts? Even a link would help.

Second, the coolant temperature varies between 80 -99 degrees centigrade. I noticed a few things maintenance wise that may be related to this. The radiator, plugs and wires, alternator and battery all look to be new. I also found that the shop that reconditioned this car put in green fluid instead of the Zerex. I'm going to put in Zerex this weekend to remedy that. The cooling fan is coming on with a veangence but the opposite fan that is closest to the engine is rotating at what I would state as a 60% clip. Enough for their to be plenty of blur but not enough for me to think that it's doing it's job. When the vehicle is in park the temp will stay at around 85-90 but once you have stop n' go traffic the range increrases to about 20 degrees centigrade. Any ideas to track this down would be great.

Third, oil pressure is highly erratic on this one and I'm wondering whether it's a gauge problem or an oil pump problem. When I start up the vehicle the oil pressure gauge shoots well north of 3. If I drive on the highway for the first ten to fifteen minutes after it's fully warmed up it will stay at three but... once I start to do the stop n' go it will go down to 2 and sometimes to 1. It will go to 7/10's at idle but even if I rev it constantly it will go no higher than the 1.5 mark after about twenty minutes. I need to determine whether it's a fouled up gauge or whether something actually needs to be replaced on it.

I really look forward to making this car work. I've had two other 89's and gave them to enthusiasts, one of whom came nearly 2 hours to pick one up. I'm an auto auctioneer so the buying and selling of vehicles has always come naturally, and with it the tendency to work on them as well. To give you a grasp of how much I like this particular model, I am seriously considering selling a pristine Audi A8 because I find this wagon to be a more fun and durable piece of machinery. I'm also sending a 1996 E300 diesel to Florida and to be perfectly honest, I prefer driving the 89' model. The connection with the road and quality of workmanship in the W124 is two clicks above that particular generation. Thanks again for all your help and I hope all is well...

macarose

MACAROSE: Congratulations on your purchase and welcome to the bortherhood of the W124/300TE. These are great cars, great people haulers, great "thing" hauler.

As for the weight thing, I think that the 300TE weighs close to 2 tons. I tried looking it up but could not find the actual weight figures. Still, these are very substantial cars, heavy and solid.

As for your questions, I think that your car is operating in the correct temperature range. As long as you are not in the red, then you are good. But if you are concerned about the operating temperature, check out the following link:

http://pages.prodigy.net/jforgione/MB_S500.html

Jim has good information regarding how to lower operating temperature. He also sells a wiring harness that tricks the aux fan into kicking in at a lower temp, thus helping to cool the engine.

I think that the oil pressure gauge may be off. My 300TE runs at full oil pressure when the engine is under load (accelarating or going up a hill). I think that yours is running too low. This is especially so in light of the fact that it seems to run normally at first, but then drops.

I'd have it checked out.

Finally, I would agree with you that the W124 is more of a "traditional" Benz. But the moderm Benzes are just as much a Benz as the older ones. We also own a 2002 C320 Sports Wagon. That wagon is a hoot to drive, it is fast, it corners flat and it handles very safely. The C320 has a number of toys and gadgets than the W124 does not have and to be honest with you, I do like the new toys.

I'd probably keep the W124/300TE as long as I can (probably longer) but there is no denying that the new wagon is a very good car on its own rights.

Again, welcome to the brotherhood (and sisterhood).

iwrock · #4 05-03-2006, 11:00 PM

Everything that you describe is what is the norm for these cars. I just had a rebuilt trannie put in, and well, it does shift tight and hard. However, if I take it easy on the gas, it tends to shift at about 3500-4500 rpms, it is as smooth as butta. Mine runs at about 100* celsius when I am in traffic, but other than that, it is what I would call a perfect daily driver. I am going to replace my oil pressure sending unit, as it reads 3 all of the time.

Also, I also feel that the W124 came a a high point in Mercedes Benz engineering. I feel it is one of the most solid cars ever built, and one of the safest. (Ask me how I know

) She is an awesome daily driver, much more than some Hyundai or similar make can offer. It is just an exeptional piece of machinery that goes above and beyond its call.

If you go back through my posts, you will find the one where I hail the W124 platform. You will also find why I know the reason why they are safe cars.

Also, welcome to the brotherhood.... Congrats on the Purchase.

simmo300e · #5 05-04-2006, 05:39 AM

The fan closest to the engine - running off the belt instead of electric - has a visco clutch which only kicks in to high gear at 2000 rpm.

If you want to check it's working, edge a rolled towel or cloth into the blades while its running and see if it stops. if it stops, the fan clutch is shot.

The important points to note here are 'edge' and 'rolled towel'

Other than that, you might want to check that the cooling system does not have an air pocket in the cylinder head. this will cause the symptoms you describe. the bleed hole is a fiddly bolt in the cylinder head, between the sensors towards the front of the engine.

Re your oil pressure, that's not right. should peg at 3 when the engine is running above idle, 1.5 to 2 at idle. I've read that using the wrong (read cheap) oil filter can cause this behaviour.

BENZ-LGB · #6 05-04-2006, 09:29 AM

Quote:

Originally Posted by simmo300e

The fan closest to the engine - running off the belt instead of electric - has a visco clutch which only kicks in to high gear at 2000 rpm.

If you want to check it's working, edge a rolled towel or cloth into the blades while its running and see if it stops. if it stops, the fan clutch is shot.

The important points to note here are 'edge' and 'rolled towel'

Other than that, you might want to check that the cooling system does not have an air pocket in the cylinder head. this will cause the symptoms you describe. the bleed hole is a fiddly bolt in the cylinder head, between the sensors towards the front of the engine.

Re your oil pressure, that's not right. should peg at 3 when the engine is running above idle, 1.5 to 2 at idle. I've read that using the wrong (read cheap) oil filter can cause this behaviour.

I just have this fear of introducing anything in the pathway of spinning fan blades....

There must be an easier way to test the fan clutch.

iwrock · #7 05-04-2006, 09:42 AM

Oh yeah, and the curb weight of this vehicle is 3475 on the nose.