: '95 SLS high idling temperature



Kadimeister
02-18-05, 02:56 PM
Hi, I'm new to the forum and very impressed with the expertise of the participants; the technical caliber of the discussion is really high, kudos!

I just bought my 1995 SLS a couple months back and overall I'm very pleased with the car. I am just concerned that the running temperature is high; on the highway it is only 192-199 degrees (at say, 60 degrees ambient temp), but once I am in the city the temp rapidly climbs to 220 and beyond and I get water coming off the expansion tank and, predictably, I later get a 'check coolant level' message.

My concern is that if I'm getting these high city readings now in (California) wintertime, what's going to happen in the summer when the mercury hits 100?

Also, a couple of minor subsidiary points, much obliged if someone can point me on the right direction with these:

1) how do I change the little bulb that lights the rear passenger door panel?

2) where is a good place to find replacement center caps for my vogue wheels?

Thanks for any help!

Spyder
02-18-05, 04:22 PM
Check to make sure that the fans are running. 220 in city driving is perfectly normal...the fans don't even kick on until it hits 223 or 225, or if you have the A/C running. The low coolant message is different though...do you possibly have a leak around your water pump somewhere or a pinhole in a hose that causes you to lose that much coolant? Mine runs at 208 on the highway...also in California, just north of Sacramento...and in town it always gets up to 226 and then the fans kick on to throw it back down to 208. The freeway temp is normal for you...the in town is normal too, but unless you're over filling the surge tank, it shouldn't spill out more than once or twice after filling...it should stay about 2-3 inches down from the top of the surge tank. Check for leaks and check back here frequently, hopefully someone else can offer more info!

oldgamer
02-18-05, 04:31 PM
1. It's perfectly normal to have highway speed temperature lower than idle (it should be).
2. I didn't noticed that at winter engine temperature is lower than at summer time. No difference at all. Even more, I noticed that at winter temperature even a bit higher. I guess BBOB explained that fenomenon once, I just don't remember.

BeelzeBob
02-18-05, 05:05 PM
The cooling fans run all the time (pretty much) in the summer when AC is possible so as to keep constant air flow over the condensor. The constant air motion then tends to keep the coolant temp very stable by default.

In the winter, when the AC is disabled (or just when driving with the AC off or in ECON) the cooling fans are only controlled by the coolant temp. The cooling fans do not even run at all below 225 or so, so it is common to see those sorts of temps when idling and in city traffic.

Very common to see lower coolant temps on the highway (due to the constant ram air) compared to the city traffic and idling where the coolant temps will climb even on a very cold day due to the lack of air flow.

The temps you report are perfectly normal....however....repeated loss of coolant is NOT normal. From your description you are seeing coolant loss at the pressurized surge tank??? Is it coming from a split in the tank or other leak source or from the pressure cap area??

Possibly you have a bad pressure cap or damaged seal on the cap. I would take the cap off when the system is cold and survey the seal and sealing surface at the surge tank....and/or just replace the cap with a new OEM cap from the dealer is there is any doubt.

Is the system full of 50/50 coolant/distilled water?? The correct concentratoin is important for freezing protection as well as boiling protection and corrosion protection of the engine. You MUST have the correct 50/50 DexCool/distilled water ratio for correct operation of the system. You mention "water" coming off the surge tank (that is a pressurized surge tank that is an integral part of the cooling system not just an expansion or coolant recovery tank).....do you literally mean "water" or coolant?? If the system has water in it then it will be boiling at the temps you mention and causing coolant loss...not to mention the corrosion damage going on. Check the coolant concentration with a refractometer to make sure that it is 50/50 ESPECIALLY if you do not know the original concentration from the previous owner or have been adding plain water to the system.

Kadimeister
02-19-05, 12:41 AM
Thanks Spyder, bolshoe vam spasiba Oldgamer, and last but not least, thanks bbokinski for all the good info.

Yeah, I guess I am maybe a little too nervous about this; I did change the pressure cap and got a new with the same rating (16 lb) one (but not OEM), although there seemed nothing wrong visually with the old one, sealing surface had some residue on it. Initially, I had a higher proportion of dexcool in there than 50/50, but lately I have been topping it off with distilled water as I have heard it actually cools better (and the freeze risk where I live is nil). I will check the hoses again to see if they are in good shape; I recall one posting where the problem turned out to be that the overflow tank was partially clogged, maybe I will try to check that although I'm not sure how.

Anyway, I do really appreciate the rapid replies. I am probably just paranoid but I have read a lot of posts on bad head gaskets and I am wary of overheating for that reason! (and are the Barr's pellets supposed to prevent that, or just to take care of the radiator?)

Thanks!

oldgamer
02-22-05, 09:20 AM
Kadimeister:Pojaluista. Vsegda s udovolstviem pomogu!

I recommend to make a small investment into Cadillac factory manual by Helm Inc. Now it's on sale just for $30 + ~$6 shipping for cars up to 1995 (two volumes). I already got mine and this is the best. Check www.helm.com (http://www.helm.com/). Look for Cadillac 1995.

mcowden
02-22-05, 10:18 AM
I did change the pressure cap and got a new with the same rating (16 lb) one (but not OEM), I had a higher proportion of dexcool in there than 50/50, but lately I have been topping it off with distilled water as I have heard it actually cools better (and the freeze risk where I live is nil). I will check the hoses again to see if they are in good shape; I recall one posting where the problem turned out to be that the overflow tank was partially clogged, maybe I will try to check that although I'm not sure how. (and are the Barr's pellets supposed to prevent that, or just to take care of the radiator?)


OK, couple of things. First, the OEM surge tank cap is rated for 15 pounds, not 16, so you might want to change that out just in case. It's possible it will be fine, but I don't know for sure.

Next, it's OK to have a higher concentration of coolant to water than 50/50, but no more than 70 dexcool 30 distilled. If you're adding plain water, don't dilute it so much that the coolant concentration drops below 50%. You will probably need to use a refractometer to check for sure because the float-type checkers are unreliable. The freeze risk is irrelevant. If you live in Hawaii, you should still have a 50/50 mix because it's the coolant that keeps the cooling system metals in good condition. Water will corrode them and the coolant helps prevent it, so get the concentration right and keep it there for best results.

If you put the Bar's Leaks into the surge tank, it's possible to clog it up. I don't know how to unclog it, so hopefully someone else will chime in here, but from what you're describing, there's no problem anyway. When you put a supplement in the system, you should only use two tubes of the Bar's Leaks Goldenseal powder or 6 of the pellets. Don't use anything else, no matter what it says on the package. No aluminum or copper stuff, just the Bar's Leaks Goldenseal or pellets. It's the only stuff that will help you. The stuff with the black fluid and pellets should not be used, and it especially should never be poured into the surge tank. Big pellets or powder only, and they go in the hose, not in the tank. The Bar's stuff is to help seal any small leaks caused by pores in the aluminum castings, etc., and it does not aid cooling or antifreeze properties in any way, nor does it lubricate the water pump. It's just for stopping up tiny leaks.

From what you're describing, everything is normal. Keep the concentration at 50/50 Dexcool/distilled water, put the supplement in there and leave it alone. The level in the surge tank should normally be 1-2 inches below the opening. If you keep topping it off and it drops back to that level, you're not loosing any coolant because of a problem, that's just how much it expands. The temperatures are normal.

Hope all that helps... Good luck and happy driving.