running cool in the mountains (cold temps outside)

[stejm]

Over the weekend, I drove Jutta up to Big Bear (approx 7200 ft) for a weekend of skiing.

Driving up (in a never-ending rain) she ran about 170 in slow moving traffic. No probs climbing 7K in about 37 miles, car was running around 175 tops.

I get to the the rented cabin, park, and let her sit overnight. The freezing rain that turned to snow did a number on the locks and doors (not to mention the 12F temps), but I got her started without any problems.

I noticed, driving around big bear, the temp would stay around 130ish. The heat would work fine after I let her sit for a while, but after driving around in the cold (around 9F), the heat pretty much stopped working and the temp stayed really low.

I'm running about 30/70 mix in the rad, and was wondering if this was the prob with the low running temps? If I increased the mix would I get higher running temps, thus heat?

Shouldn't the engine regulate the temp regardless of airflow over the radiator (i.e., maintaining a basic running temp @ 175 via the thermostat) ? I know when I lived in canada as a kid the parents would put cardboard over the rad when the temps hit -20C or so, but should temps running around 10F affect her this much?

[Tomguy]

You have a bad thermostat. A weak spring in it is opening it at much cooler temps than it should open at, thus making your engine run cold (and less efficient)

I ran 175 in traffic all the time, but on the highway it'd cool to 150 or so (or if I started out on the highway, it'd never get above 150). When I replaced the thermostat, this was solved (and also gave me SOME heat, I had none before that - now I've pretty much solved the poor heat I believe (but that was due to clogged heater valves).

The cardboard doesn't do too much when your spring is strong (thermostat is good) - it might help it get to operating temp a little quicker but not really too much so unless you're doing 40MPH+ with light throttle The thermostat, when cool (especialy at below freezing) allows very little to no coolant to flow.

[psfred]

First, you are lucky you didn't freeze the radiator with 30/70 antifreeze/water (if I read that correctly). Unless you are going to be in temps below -20F, use only 50/50. This is just as important in hot climates, since you get better boil-over protection as well.

Second, you are going to get significantly better milage with a new thermostat -- cold running enrichment stays on till 175F, so any time you are colder than that, the "choke" is on.

Peter

[stejm]

Took her to my indy mechanic and replace the thermostat - t'was bad.

Drained and flushed my coolant, so it's now at 50/50. I wasn't even thinking about the coolant mix before I went up there!

Disaster averted!

I must have blown out a good deal of carbon on the ride - she's running better than ever.

thanks, guys!

[Tomguy]

Better running is probably a result of the engine running at normal operating temperature - thereby kicking off the cold mixture.

If you saw a lot of black smoke (especially when you floored it), it can probably be attributed to just that fact - you should get better mileage now too!

[mzsmbs]

Well, I have somewhat similar problem that I was gonna post about so here it is. In advance any help would be appreciated.

The car most of the time runs at 175F in the cold but does flactuates to 150F at times. Ok, my problem is that the heat works barely sometimes. When I crank the heat the air comes out cold. When I just have the fan on low then the air is hot. As soon as I turn it up it turns cold. When sitting in traffic it tends to get cold no matter of the setting. Then when in motion it warms up again. Overall it is never really hot though. Ive been thinking of changing the thermostat but olso wondering of the symptoms could be because of plugged up or "dirty" heat exchanger. It's been cold here and I need to figure it out for the next warm up this weekend (balmy 34F).

P.S. I forgot to adjust the antifreeze ratio and have slush in the radiator in one of my other cars. It would not start yesterday. If any body has any ideas on reviving it, please share..I have no garage and have to do everything curbside.

Dope!

[psfred]

Get a new thermostat, you are loosing temp control on the highway. Also, verify that you actually have enough coolant in there -- must be up to the marker cold, or heater circulation is impaired by air bubbles in the return line.

No heat with the fan running on high is low coolant flow -- I have that problem on the 280, needs a nice citric acid flush to clear all the calcium carbonate out.

For the slushed car, drain some coolant and add straight glycol. Starting shouldn't be a problem unless it won't turn from having ice around the water pump -- if it cranks, it's something else, not the ice that's keeping it from starting. Gasoline car, try a whiff of starting fluid, works wonders. Go lightly, you only need to get a couple cylinders to fire a couple times to get it running.

Check for fuel delivery, too -- could have some water in the tank causing fuel starvation.

Peter

[Tomguy]

Peter: The problem isn't the water in the gas (at these temps), it's ice blocking the lines! I used to use drygas in my tractor - it works when you add it to the tank before the water freezes. Once it becomes solid, you have to wait for the thaw to start it! (I used to take the line off and blow it out, but that's not so easy on a car...)

I need to do a citric flush myself, I'm afraid. I had very poor heat and my idea of vinegar and baking soda run through (JUST THE) heater core helped, but not enough to please me. Once I patch my rad up again (It was leaking heavily, I soldered it, it began leaking in another spot, I soldered that, now it's leaking in 3 spots that I need to solder - all different than spots I've previously fixed!)

[psfred]

Tom:

Take your rad to a radiator shop and have them check it out. Probably has serious corrosion, unless the leaks are around the top or bottom tank (bad solder), in which case they can do the whole job at once rather than trying to fix a leak here or there. They may even be able to re-core it at a reasonable price.

Peter

[mzsmbs]

Thanks you guys.
I'll put on a new thermostat and then see. My radiator is one without overflow tank but topped as much as it will hold. It does tend to spit some of it out but just below the valve. Is it hard to get to the heater core in a w114? I might look into gettin a new one or boil this one. Now the benz will not start either but I'll start a new thread on that in a few.

The other car: I added more straight glycol last night and it helped the slush desolve. The car still would not start today so I pulled the plugs and cleaned them (a bit wet from starting fluid I tried last night.) checked the wires distributor etc..everything seemed ok. It still will not start. I did add heet to the fuel last night. I guess it could be frozen gas in the lines since I don't smell the gas after repeated cranking. I'll check for spark in a few after it gets dark. No available helper .

I'll keep you updated.

Thanks again.

[Tomguy]

mzsmbs: You should ONLY fill the rad to the top of the indentation (facing the engine). You can see it inside, if you can't, it's probably too full.

Peter: It's a bad solder along the top. The rad was a replacement a few years back and I believe that they resoldered it, possibly recored it, and it was a bad soldering job along the top. I went all along the front the second time, redoing the entire joint, and it's fine now; but the edges are the problem points now - they didn't leak and I didn't feel like unsoldering the support brackets to repait them, but I suppose when I fixed the main leaking source, the pressure caused another area to go.

This time, when I take it off, the entire seam is being resoldered. It's a PITA, yes, but it's better than adding coolant often.

[mzsmbs]

Got a new thermostat and will probably put it on tomorrow.
Here is a link to my other thread to my non starting MB .my 250 won't turn over all of a sudden
I'll look for the antifreeze level marker tomorrow too.

Thanks

I got spark in the slush car, which is good, but it will not start yet. I am gonna wait till it warms up this weekend and try then, maybe it is the water/gas in the lines. We'll see