OK, my really getting tired of this godd***ed car running hot all of the time. I took the car out today and messed around with the elec. cooling fan to check if it was running the right way. (Its a Hayden Rapid cool and it reverses itself if you switch the wires) Of course, it ran hotter instead of cooler(just north of the top white line...not in the red), so I brought it back to the garage to switch the wires back...

When I opened the hood, I could hear a very slight hissing sound coming from the small diameter heating hoses on top of the engine. (1/2 inch it looks like - leading off the coolant return line to what looks like some sort of valve or sensor just forward of the spider) The hissing seemed to be pulsing and I couldn't see any steam or see anything dripping.

I looked under the car and found that I had fluid on the floor under the car. it looked clear like coolant or water, but it felt cool to the touch. I backed the car up to check it out and when I looked at the floor where I backed to, there was a little fluid there, too.

I let the car cool a little while I switched the wires back, and started the car up. No leaks or hissing sound when I shut it down again.

What could this be??? I'm sick and tired of worrying about this car running hot every time I get stuck in traffic. Now I have to worry about leaks, too????

I'm really really frickin sick of this

 

Faulty thermostat??

 

Get a pressure tester that you can attach at the top of the radiator on the small bleed hose. With a couple hose barbs, a 30 lb gauge, a schrader valve and a bicycle pump you can make one for a few bucks that will allow you to test your peressure cap, hoses, etc.

Aside from the running hot issue, a pressure cap that doesn't relieve pressure properly can cause other things to fail. Also, it sounds like you may have a lot of air in the system. Try to work that air out of there before further troubleshooting, and get that fan turning the right way.

 

Brian hoses are hoses. If it's too hot the fan is either not doing a good job, or isn't getting turned on. It should come on at an appropriate early point .. does it?

 

Heinrich,
The elec fan goes on just before the upper white line. I have a 75 degree fan switch and thermostat in there and it seems to work. I did the unofficial "fan clutch test" and I get a really strong blast of air off the belt driven fan at 3000 RPM.

Dave,
I replaced the cap on the expansion tank last summer with the correct Behr one. the PO had placed a Delco cap on the expansion tank which was so tight I thought I might snap the neck off the tank trying to get it off.
When I replaced the thermostat, I thought I burped the system pretty well, but I can still hear fluid moving around in the hoses when I shut the car down. Could I have a big air bubble in there that is messing things up?

Thanks for the help with this. I want to drive the car on longer trips, but I am paranoid to drive the car too far in case I get stranded.

Brian

 

Greg at Precision wired my fans direct so they run all the time. Not sure about how good this is but I trusy his judgement.

 

When you say "upper white line", there are 4 on the gauge. Do you mean that it's approaching the 4th mark at the hot end? If that's the case then the first order of business IMHO is to find out what that really means, IOW measure the actual temp at the top hose. These gauges may not read right due to connection problems, flakey senders, and even flakey gauges. Also, check out the coolant. Whatever color you are using, it should be clear(green, blue, orange) rather than opaque. If you changed from one color to another, there are issues with some combintations where it's critical to flush every bit of the old stuff to avoid deposits. I think there may be some same-color but different type coolants available. Might want to check up on that, and/or wait for one of the coolant experts to chime in. Dr Bob? Wally? Anyone?

 

I would check the thermostat to make sure the correct type is in there. The 928 thermostat has a little foot on the end that directs coolant when the stat is open. Maybe the po installed the incorrect type.

 

Is the A/C working? could be condensation fluid from the A/C; not a problem.

Guy in UK had a similar problem with a 79, eventually he gave the cooling system a real good flushing which seems to have fixed the problem.

Marton

 

Dave,
My gauge has 3 white line and a red area at the top. My car seems to like to sit right up near the third white line all the time. When it gets hot, like when I've been stuc in traffic, it moves up on to the third white line. Could this be the normal running temp and my gauge is just plain wrong?

Jim,
Its an OEM 75 degree thermostat and fan switch. I changed them 2 summers ago.

Marton,
A/C is dead. I found the disconnected compressor wire yesterday. I can't seem to find the end coming off the compressor, though. :-(

I am planning to flush the system and clean out the gunk that's probably in there...

Thanks for all the ideas, Guys. You are the best!

 

My 79 has the 3 white lines. In normal running (60 kph up and etc) the temp sits at the bottom white line. if it sits it climbs towards the top white line (not the red line - basically three quarters up) at which point the electric fan kicks it and it stops rising. A few minutes of normal driving and it drops to the bottom white line again. It has never actually reached the top white line.

I suggest your thermostat is not functioniong correctly or it is the wrong themrostat for your car and is not kicking in until it gets much hotter than it should. BTW I am in Western Australia, it gets HOT, 38-40+ in summer.

Steve

 

Brian -

There are MANY things could could be an issue...from the very simple (and 'free' to fix), to more complex and more $. Remember - this is a 25+ year old cooling system!!!!

1- You need to check to see what the TRUE temp is! It could be as simple as your temp gauge is innacurate!! (FREE - if you have a temp gun or sensor)
2 - Has 25 years of crap accumulated in your radiator? Is the air flowing through it? You need to take a compressor and a 'blow gun' and make sure that all the air flow through the rad is unrestricted and blow out all the crap remember - any ;crap' lodged itself from the front...though you should check air flow front-to-rear, blowing out the junk should be done back-to -front.(FREE - if you have a compressor and blow gun - or have a friend with one!)
3 - As Jim G. pointed out, there could be some 'jello' caused by the mixing of incompatible antifreezes. If #1 & 2 prove to NOT be the issues - you need to pull the radiator and flush and check it. Pulling the rad is NOT a difficult job. (FREE - just a couple hours of your time!)
4 - Do you have the proper ratio of coolant to water? Too much of either can cause some problems. You small bit of CLEAR liquid is likely NOT from your cooling system - as you stated that it is cool to the touch.
5 - IS your radiator flowing OK? Easy to do a 'basic' check...Are the main (LARGER) hoses on the top and bottom of the rad 'taught' when hot? Are they warm-to-hot to the touch? (Remember - the return to the engine should be cooler...indicating that the radiator is doing its job).

Check the above...they chould give you SOME insight as to where to go from here.

 

Brian,

Just for clarity, have you replaced the belt driven fan with an electric? Your post could read as if you did, but could also be interpreted as if you were experimenting with the aux fan. If you are still running the belt driven fan, the viscous clutch may have gone bad.

 

After re-reading everything...if your temp gauge isn't hitting the RED - (and it happens to be fairly accurate)..then your car is NOT overheating! Proper engine temp is important (75-90C). Start with my suggestion #1 above!

 

DOH! I guess I could have just walked out to the garage and looked... my faulty memory told me that there was a top white line with a red area next to it. Maybe I've been spending too much time looking at my voltmeter lately...