2005 S60 2.5T AWD - No Heat / Overheats on hills

[MarcM]

It's fine in cooler weather (below ~63°F). Today overheated again. Head gasket blue>yellow fluid test shows no leak. Drew a heavy vacuum (actually collapsed radiator hoses), vacuum stayed. Swinging back to water pump being bad.
Chasing shadows in NH.

[MarcM]

Alrighty. Have been driving the car like this for quite awhile now. In the morning @ 20-53 deg F all is good. No heavy footing the pedal. On the way home and it's in the real low 50's, it's fine until one spot on the way home. More than that it happens about 10 miles from departure. I let off for 15+ sec, the needle doesn't move that much back down until I step on it. Not so sure it's the waterpump. Going to do a flush with Fleetgard Restore first. Found this on a diesel forum:

From the M&S Tech website: <removed, dead link>

RISING ENGINE TEMPERATURES

Rising engine temperatures at highway speeds could mean you have a partially blocked radiator core. We receive many calls describing the following problem: when the vehicle is driven at highway speeds, the coolant temperature will slowly or rapidly rise; when the vehicle is stopped and allowed to idle the coolant temperature comes down rapidly. If you have noticed a rise in coolant temperature at highway speeds, I would inspect the radiator in the following manner for silica gel build up. With the engine cold remove the radiator cap. CAUTION: there will be pressure in the cooling system, remove the cap SLOWLY! Drain or siphon some water out of the radiator so you can see the tubes coming out of the core. If you see a build up of a white substance around the top of each tube, this is silica gel and it must be removed. The silica gel will restrict the water flow through the radiator core and also acts as an insulator. To remove the silica gel, install into the radiator (not the overflow tank) one half gallon of NalClean 2001. Leave it in the cooling system for 30 days and use the vehicle normally. After 30 days completely flush the cooling system to remove the silica gel and the cleaner. Then install the correct amount of a low silica anti-freeze like Peak and two pints of PenCool 3000, top off the system. check for leaks and drive the vehicle for a few miles so the thermostat opens. Then, when the vehicle is cold, check the fluid level in the radiator and top off as necessary. The PenCool 3000 will also reduce the cavitation erosion problem. Please do not wait until engine temperatures become so high that interval engine damage occurs, and don't use any 10 minute flushes, they are very caustic and will damage the radiator and heater cores. M&S

I still have to drop the glovebox and check the blender motor that runs the heat/cold and at least make sure it's not that.
Backstory: Car had red antifreeze. Noticed it on pre-buy inspection, but low. When I picked up the car after purchase, someone topped it with standard green antifreeze.
I've been spending the better part of 3 hrs hemming and hawing over using vinegar, Prestone or BlueDevil flush/cleaners. Going for the throat and using the non-alkaline Fleetgard (Cummins) Restore (Restore Plus is more for iron engines with rust & scale).

[MarcM]

So I did a cooling system flush. Now I have cabin heat... and a coolant smell in cabin (knew I might open a can of worms with the vinegar trick). Car still overheats on long hills. Didn't replace the water pump. Not certain it would have done much for it anyway. Going to check the coolant hoses to the turbo for kinking next. Doing anything and everything to not admit it might just be a head gasket. Ugh.

[vtl]

Head gasket is not that bad.

[MarcM]

Yeah it is a simple job for me, but I just hate working on cars after 40 yrs and hundreds of cars later.
Found a guy down in Shirley, MA that will lap the head vs mill/grind. Cheap enough and it comes out flatter w/better sealing of the gasket. As an engineering family, it's a no brainer. Guess I'm going to have to order the complete head gasket set and heater core. From what I gather I'll have to pull the valves anyway. Might as well get a slug set and fix the first-10 mile tick too.

[vtl]

Valvetrain ticking could be due to o-rings in oil sump.

[zanzabar]

If it's the headgasket you're going to see coolant in the oil (send a sample in to Polaris or Blackstone) or oil in the coolant (hard to tell I suppose with all the other gunk) or combustion gasses in the coolant which you tested and didn't find. I'd think about waiting on the HG.

Couldn't this still be the spooge in the radiator or other partial cooling system blockage? It's hard to get that crap out. I've had some cars that needed to be flushed 8-10 times before the water came out cleanish. Sounds like you pulled every hose possible and did a good job of emptying the system, but there are so many places where globs of gunk can get lodged.

[MarcM]

* RESOLVED * (I think)
Today it was 81 deg. Car didn't overheat once. Ran from office, across the city and back. Parked 30min and made my 35min ride home.
What changed? Back in February I replaced the condenser and radiator. The right tank started leaking on the radiatorl. So I (not going into the debacle, just buy Volvo is all I'm saying) replaced the radiator. I and a sibling spent HOURS with dental picks trying to get the sand out of the stock condenser and bend the fins back. I got PO'd and spent the $130 for a new one. The fins on the original condenser's bottom half (exposed thru the bumper) were staved over and full of little pieces of dirt. That dirt was also past the condenser and filled the gaps between the old radiator's fins. Somebody went into a snowbank. Which explains the zip tie holding the front bumper on where a body fastener is missing.
I was doing 60 to <ahem> 90 and it didn't overheat once. Of course the cooling fan is stuck when the engine is running; until I can get my nephew moving on not forgetting his HVAC vacuum pump from his shop to his house so I can recharge the AC system. Thinking I'm going to have to explain what's up to get a fire going.

[zanzabar]

I'd plan on still doing another complete flush soon. And I would also strongly suggest replacing the water pump just to be safe.