Ever since I did the WP on Lisa's 1990 240 it runs hotter than before. I also put in a new T'stat and flushed and refilled with 50:50. Last summer on holidays and climbing through the mountains required turning on the heat, I added some Redline water wetter as a stop gap measure which didn't make much of a difference.

I replaced the T'stat this winter (both 92 C same as what I pulled) and the old one was stuck open. Changing T'stats hasn't changed anything?

What seems counter intuitive to me is that cruising on the flats in hot weather causes the gauge to move up. Climbing hills pushes it further although it's never overheated because I turn on the heat. What seems odd to me is that when stopped at a light after cruising on the highway the temp drops back to 9 o'clock on the gauge. It also stays at normal temperature when driving in stop and go traffic and when sitting at lights, I would have thought with no airflow it should be warmer than cruising on the flat with more airflow??

The WP that came out was thoroughly pooched, the bearings were so bad that the impeller was running on the block. I would have thought that the car should have had issues then, not after fitting a new pump, T'stat and flushing the system. I am running a Black overflow tank cap that replaced the factory Green one if that counts for anything?

Am I missing something obvious here, the current issues/conditions seem backwards to me??

Fan clutch?

Did you use Dex-Cool, or some other brand of extended-life antifreeze? The old junk is getting hard to find for whatever reason, but I'm becoming more and more convinced that our old junk doesn't like the stuff blended for 5 year lifespans.

The classic line you'll hear is "vapour lock", but our cars simply don't do that. It's so easy to get all the air out of our cooling systems, a child could do it. Unless you were filling the rad with the car pointed down a steep driveway, you are probably fine there, and anyway the first time you drove it the system would bleed itself and you'd end up needing to add coolant to the reservoir, but the block would be full...

One could also ask if your belt is slipping at speed, and grips enough to keep the engine cool at idle-ish speeds and times of low power requirements. One could also ask if your crank pulley has separated - B230 are known for this, and I've encountered it as well - and the crank isn't effectively driving the sheave ring. These would also show up in poor charging and/or air conditioning and power steering performance.

I KNOW that these engines have cooling systems designed for sub-4500 RPM operation, ESPECIALLY in B230 guise. Large crank pulleys and small water pump pulleys overdrive the pump, and even with the B21/B23 combination of pulleys I've popped out more frost plugs and exploded more heater cores than I care to think about. You're not driving it that hard, though, and your cooling system should be well up to the task of it.

I also KNOW that there are water pumps and there are water pumps. There are pumps with stamped impellers and there are pumps with cast impellers. Cast impellers are preferrable here - they're more efficient.

We just went through cotten/pollen season - the air side of your rad is clear, isn't it?

So there are a lot of variables. If you installed a stamped impeller pump and used Dex-Cool, and are driving it with the small WP pulley and a destroyed crank pulley, I'd say yeah - you might have issues.

Keep in mind, too, that these cars are equipped with biased gauges - the needle seeks the normal position, and will stay close to there during normal temperature variations to keep normal drivers from freaking out when they climb a hill. These gauges do fail and will start pointing in all sorts of funny directions, so if you haven't overheated or seen other signs of extremely high temperatures other than the gauge, you MAY not have a problem. Get a meat thermometer and go collect some data.

Good luck

Uh-oh...you're starting to sound like Craig...

You tossed out the DexCool right? Go to the UFA, they still have the green stuff for cheap. Sounds like you're moving water when it's spinning at idle and not at speed. You could take the rad to Don's and see if it's OK, the system should burp itself, your heater core works, the only thing that makes sense is that you're not moving the water through the system. Is it a GMP (or is it GMB) pump or a Hepu/Volvo? I've got a spare cast impeller pump and the gaskets/rubber rings for the pump if you're interested. Bring it by on the weekend and we'll swap it out in a second and you can get your bung tool back (thanks by the way).

That crossed my mind except for the hotter with good airflow, cooler with none situation I am having. I'll check it out though.



Nope, good old green stuff.



I've drained and refilled the system a few times now and never an issue with air as you described. Reservoir holds a level fine as well.



I'll have at look at the belts and pulleys. We're not experiencing any squeeling, charging, power steering issues though, and the 2/90 AC works good. I know when I did the TB/WP service I painted dots on the crank pulley/harmonic balancer halves and they never moved, will double check if the dots are still there and in the same position.



I used a HEPU WP which I think is cast? Everything I read said HEPU were just as good OE?



Pretty good for pollen out here, although Lethbridge is pretty snowy in spots, will double check the rad but I'm pretty sure it's clean.

I thought about the Volvo gauges and how they are set up to keep the average driver all warm and fuzzy. Trouble is all of the temp swings started after I "improved" the car by catching up 10 years worth of neglected mtce., unless of course I started temp gauge watching after doing the work?

Although.... It just donned on me that I also swapped clusters on this car somewhere around the same time as all of the other work was getting done, so I am possibly remembering the old cluster's temp gauge action??!!

I think Lisa has one of those fancy electronic meat thermometers, seeing as how it's her car she shouldn't mind if I use it to gather data? (Just pulled it out of the drawer, this is cool! Has a scroll through menu for what you want to cook: Beef/Pork/Veal/Turkey/Volvo... whoa, stop right there!!) Damn the cord is short on this thing, probably going to have to duct tape the display unit to the hood. Hope I can still read it while driving...

Thanks for all of the ideas guys, I'll let you know what if anything I find.

Hey Craig, looks like you were posting as I was typing (slowly).

Affirmative, plain old crappy tire green stuff at 50:50. The WP is a Hepu so it should be good. The system is definitely burped and the heater core throws LOTS of heat. (Picture us last summer climbing passes in the Rockies at +30 C with the heat on full blast... )

As I posted earlier I have a few things to double check and should try and get some actual temperatures to see if it's just the gauge. That being said it seems pretty consistent with heat at speed and cool at rest so I'm giving it the benefit of the doubt, for now. :shrug:

I'm not sure if an IR digital thermometer thingy would work...but I do have one that we can point at things and imagine that we're fixing something. I suppose if the fluid is exposed, it would work.

I've been trying to think of something with a long enough cord so I could tie the sensor to the engine and fish the cord out. If the display was tapped to the cowl you could drive around and get actual temps in all situations. Lisa's meat thermometer might work, and it's not THAT expensive that I'll get in too much shit for wrecking it.

Plugged rad perhaps? The only time I had overheating issues with my 240 turned out to be internally restricted rad. Maybe that new pump pushed some built up crud up front?

RT

It's a good possibility and probably where I'm headed next if everything else checks out. I have the car tomorrow so hopefully I can find something.

I was going to mention the plugged rad but figured that since you flushed it, you probably got the rad cleaned out. Possibly not - flushing can toss some nasty junk around. Still, with a crossflow rad I could see the bottom tubes getting pluggy but all of them?

Sounds like you've got all the bases covered, Jim, except for the assumption that green coolant = 2 year. I really need to get cleared up on this coolant folklore before I disparage any products, and I've never really had COOLING problems per se, but I've noticed a difference (not sure on the trend of the difference, though) in the heater output between fluids. The only hard experiences I have are with the Evans NPG: Roberta's car pinged like crazy, put out no heat, and the oil temperature went sky high. Anyway, I'll bet you look at your coolant bottle and it says something like "compatable with Dex-Cool (and a bunch of others)"

That's why I said to go to the UFA and buy good old ethylene glycol and stay away from anything that is compatible with that orange stuff. I've only read the stories, but none are good...sort of like seeing what ethanol does to rubber parts. Those of us running old cars have to be on guard for new formulations that basically kill our cars.

So you're saying green coolant is only good for 2 years? The coolant I have in the car is only a year old.

Also, to be totally truthful/clear I never actually "flushed" the system. I was rushing to get the car done for holidays so it was a drain and fill operation.

The old stuff? Yeah, it was supposed to be changed every 2 years. It was good for a bunch longer, but the lubricants and anti-corrosion properties deteriorated after time, long before the coolant got dirty or anything. Kind of like changing your oil every 4000 km (or considering your car "old" at 120,000) - a bit excessive, but not unreasonably so.