SidViscous

YEah well..... <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" /> <img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" />



At least we don't have whacko politicians.....

Okay we do, but not that whacko

&lt;Mutter&gt; stupid sun baked Californians &lt;/Mutter&gt;

IPSC

I think I am begining to make progress. When I backed down my drive way this morning to go to work I heard sloshing from my glove box. AH HA air in the system. When I drove home at lunch the temp did not go all the way to the top white mark. So I got out the wrench and the pans and cracked the bleed valve and what do ya know? VERY foamy coolant poured out. So I let it bleed for a few mintues. Now the temp gage at least shows what apears to be the thermostat opening by lowering about a 1/4 every so often. I will Bleed some more. The shop wants the car back so they can mess with it and I will take it in tomorrow if I can't solve this tonight. Frustrating to be sure.

IPSC

Bryan

There's still air in your cooling system. As you sussed, the sloshy noise you heard from your passenger footwell is air in your heater core.

I think you just need to finish bleeding it. Run the engine with the heat on full blast and bleed it some more. I've had good luck putting a good old lip lock onto the reservoir and blowing into it until I almost pass out, while simultaneously opening the bleeder bolt with a 12mm wrench in my left hand.

Yes make sure you have plenty of coolant in the reservoir. If it gets empty, it'll pull air into the system.

As far as a head gasket goes, I knew mine went by the huge plumes of steam in the exhaust at certain times.

Bryan

IPSC

Ok I have finally gotten all the air out. It really did take about 20 bleed attempts. The car now runs just below the top white line. Here is something interesting to note. The fans seem to have no effect whatsoever on the cooling. The heater in the cabin does… Not a lot but it is noticeable even to the four different fan settings. With the heater blower on high the car runs just above ¾. With the heater blower off, it runs at the bottom of the white mark. This leads me to two possible faults. First is that the thermostat is opening at a temp higher than 180 degrees, or that the radiator is now somehow plugged. What is the possibility of a water pump change loosening up some scale in the system that is now possibly plugging the radiator? Second possibility is that the gauge is off either the gauge itself or the sender unit. I still have not located the electrical connector that unplugs the sender. Is it the square plug at the front of the head on the right side above the exhaust? My thought process is this, I want to trouble shoot the gauge first. I “figger” that it will be easier to ohm out the sender and check the gauge rather than drain all the coolant and pull the radiator. Any ideas on how to check the gauge?

IPSC

BartW

I am encouraged by your post. My car started running hot when it got cold outside, what the f##!@*$%@*(&??? I was thinking. Someone on this board suggested I bleed the coolant (I was hearing the same noise in glove box) I did it and it helped but it is still running hotter, now I know it may take a few attempts.

nh3

While the car is hot, do you guys have cold spots on the radiator or bottom hose? As far as bleeding goes I have found that the "mouth to mouth" method works best but it's DANGEROUS for those who don't know what their doing.

nh3

IPSC

New Update

I have laid hands on an infrared thermometer and taken temp reading directly off the engine and radiator and this is what I find. With the temp gauge pointing at the top white mark (supposed to be 100 degrees C or 212 F) the front of water pump housing were the thermostat lives is 200 degrees F. The radiator top (the part you can see through the holes in the unibody) also reads between 195 and 205 degrees F. Now here is something interesting. The temp is not constant from one side of the radiator to the other while it is heating up. The passenger side is about 20 degrees cooler. Once it is hot however then the temp evens out. So now my new theory is that the system is indeed working and that it is just too hot of a thermostat 195 or 205 maybe?. May gauge may be off by 5 or so degrees as well. Does anyone have any differing opinions? I have acquired an actual Porsche 180 degree thermostat and I think that would be the quickest and easiest thing to change. However, I am not looking forward to flushing and changing the coolant and subsequent bleedings that will go along with it. Since this is a brand new water pump and it has only been in a short time I don’t foresee too many problems getting the snap ring out… The new thermostat only has one seal with it. What is the correct position of this seal? It appears to go around the outside edge. Is this correct? Also which direction should the thermostat go into the housing?

IPSC sends

944Play

[quote]Originally posted by IPSC:
<strong>So now my new theory is that the system is indeed working and that it is just too hot of a thermostat 195 or 205 maybe?</strong><hr></blockquote>

That doesn't sound too hot to me. From what you have described, it seems like your cooling system is working properly. Don't put a huge amount of faith in the dash gauge, just notice if it starts doing something really weird. It's not a super precise instrument.

New tstats have a seal that wraps over the outer edge. Spring side goes in the pump. Newer waterpumps have a 7mm (old: 4.5mm) space between the tstat seat and snap ring groove - a washer (900.234.160.00) is supposed to go between the snap ring and tstat. I wouldn't bother with changing it unless the coolant was boiling over all the time. GL!

IPSC

I do realize that the accuracy of the gauge is imprecise but it is pretty close to what I am reading with the infrared thermometer. The gauge is pointing at the top hash mark (supposedly representing 100 degrees C) and the head is reading 205 to 212 degrees, measured off of the intake cam cover. I don’t think that is normal operating temp and it seems a bit high to me. Am I wrong? I thought the engine was supposed to run around 180 degrees. The cooling system needs to run cooler because right now it is cold out, 40s to 50s during the day. If we get a warm spell I don’t want to actually overheat the engine. I think that what is happening is that the thermostat is not opening unless it gets really hot (above this 200 plus degree threshold) and that the only real cooling that is going on is kind a percolating effect backwards through the top hose then through the drivers side of the radiator because that side is hotter. Once the thermostat does open it doesn’t stay open long because there is such a disparity in temperature from the coolant rushing in that it immediately closes and no real cooling occurs. That’s my theory anyways. Ok my new thermostat has the seal with it but not the spacer. 7mm seems like quite a bit, what will happen if I don’t have said 7mm spacer?

IPSC sends

944Play

[quote]Originally posted by IPSC:
<strong>The cooling system needs to run cooler because right now it is cold out, 40s to 50s during the day.</strong><hr></blockquote>

Why does it need to run cooler? You want the engine to get nice and warm to get the best efficiency and the oil to get up to temp so it can boil off any condensation. Also nice to have good heat in the cabin. As the ambient temps go up, the tstat will open accordingly.

The 944 has a recirculating cooling circuit - when the tstat is closed, water still flows through the engine.

As for the spacer, if you have a newer waterpump, there will likely be one in there already.

Again, if the coolant is not spitting out the overflow pipe and the overtemp light never comes on, you're probably OK as far as cooling. If it IS puking out coolant and you're still finding "air" in the system... you know.

IPSC

The problem is that the thermostat is not opening till at least 200 degrees. That is 200 degrees at the thermostat, which means 215 (and i just found a spot that reaches 220) on the head. Also at this temp my oil pressure starts to go down, I guess the oil is getting thinner due to the heat. This temp range seems excessive to me. If I am wrong someone let me know. Anyway when the thermostat does open the temp does drop to about halfway now, but then immediately starts to climb slowly back up. I think what is happening that it is taking soooo long to open the coolant in the radiator sits there and has had time to cool way down. I have measured it as low as 110 degrees. Upon thermostat opening all the very cool coolant is then rushed through the system very fast and hits the open thermostat causing it to close and the vicious cycle starts over again. At least that is my theory. I am going to bite the bullet and try and change out the thermostat myself this weekend so I will let everyone know.

IPSC

IPSC

Well I have finally solved the problem of the S running hot. It was indeed the thermostat. Got up this morning drove to the auto parts store and bought some snap ring pliers. Stopped at the Grocery store on the way home and picked up some distilled water. Arrived home, let everything cool down, then put the beast up on jack stands and drained the radiator. I could not find the engine drain plug so I pushed the thermostat open till all the coolant drained. Thank goodness for big pans. Then the fun began. The trick to getting the SNAP ring out is being able to see it. A tremendously bright flashlight helped here. It was not easy and this is a new snap ring in a new water pump so there wasn’t any corrosion to fight . Once I had the thermostat out I hooked all the hoses up and ran fresh water through the system till all the green coolant was out. Pulled the lower hose and let everything drain. Went into the kitchen and tested both the thermostats in a pot of water and what do you know… The thermostat installed by the shop did not even begin to crack till 205 degrees F. The new one I ordered from Don at EBS started to open at 175 and was fully open by 180. The other one never opened fully even at full roiling boil of 212 degrees. So, should I go back to the mechanic who did this and ask for a refund on a thermostat and two hours labor (at their rate) of course? I doubt they would but hell they wanted to pull the radiator and the instrument cluster because they said it would be too much work to change the thermostat. “Besides that’s a brand new thermostat so that isn’t causing the problem”. I will say this about Porsche ownership it is a never-ending learning process. Anyway after refilling the system with the Orange phosphate free stuff and distilled water, the temp gauge now sits at 1/3. At idle with no fans running, the temp will migrate slowly up to 2/3 at which point it goes right back down and with the low fans engaged it will stay there. Also I still don’t have all of the air out of the system so that will be fun but at least I know how to do that.

IPSC

Peckster

I'd say, time to find a new mechanic. Just because they've done a few doesn't mean they are competent. You are well within your rights to ask for a refund. It's the least they can do, considering how much time you've put into this.

Congrats on fixing it yourself!

Luis de Prat

IPSC, I just read your thread and admire your perseverance. I live in a very hot climate year round and was having similar cooling issues with my '83 after having the water pump switched and they drove me crazy until I changed both the fan switch AND the thermostat to lower temperature versions.

Thermostats can be defective and not open, which your mechanic should have considered when certain parts of the system were cooler than others and yet the car ran hot overall. You could try to get some money back, but it's a tough call since like you say, they're no experts.

On my car, a combination of both a higher temp thermostat that wasn't opening properly and a faulty fan relay were the culprits. The running temperature dropped significantly with the lower switch and thermostat, but still not to normal temperatures. BTW, the lower units are made by WAHLER for the VW Jetta. I opened the relay which seemed OK but apparently was not driving the fans correctly because it began clicking. Changing the relay got everything back to normal.

One hint to bleed the cooling system is to park the car on an incline, facing up. Also, be careful with the bleeder plug because they can crack and leave you with a gaping hole in your system. This happened to me luckily while I was in the PEP BOYS parking lot and was able to susbtitute a bolt for the plug until I got a new one from the dealer.

led

A couple of months ago I broke the metal elbow when I tightened the screw, water kept coming out so I kept screwing 'til it got screwed . Apparently the PO replaced it with a regular screw that was just a bit longer and didn't seal properly