Author Topic: Thermostat and Coolant Bleeding Issues (Read 35626 times)

iamcreepingdeath · « **Reply #105 on:** October 07, 2009, 06:38:47 PM »

OK so i am about to put in the new t-stat.

BUT, before that, i thougt i'd say what is currently happening. Ok with my radiator blasted out, it seems to be flowing better, but not enough it seems. When i drive, it seems to run below the 1/4 mark on the temp gauge, but the second i come to a stop, the temp gauge starts to rise, and if the car is idling long enough, the temp will go all the way up to the 1/2 mark

When i rev the engine, the temp drops down again, and the lower radiator hose gets hot.

synopsis:
when the car is idling, not much flow through the radiator, radiator stays cold, engine heats up.
when engine is revved, more flow through the radiator, radiator and lower hose warms up, engine cools down.

Do i need a new radiator?

iamcreepingdeath · « **Reply #106 on:** October 07, 2009, 07:55:35 PM »

Ok i installed the 75 degree t-stat, and i primed the lower coolant hose with some water as was mentioned above, bolted everything back together, took out the bleed screw, filled the coolant until pure coolant (no bubbles) came out of the bleed hole, screwed the bleed screw and coolant cap on, started the car, let it warm up (temp needle bouncing all over), then opened the bleed screw, took off the coolant cap, filled the reservoir to the rim, then revved the engine, coolant squirting out of the bleed screw, until the coolant level in the reservoir dropped to the cold mark, then closed the bleed screw, and replaced the coolant cap.

So then i took the car on a drive to the gas station and back (to get gas) and Lo and Behold! For verily i say unto you! the temperature needle never passeth the midway point but tarryeth in such a place to be between the 1/4 and 1/2 mark, and it stayeth there, and bounceth not, for the entire trip!!

So far, it looks like everything is working as it should! the needle is in the right place, consistent, and doesn't rise when the car is idling!!!

BUT, i am not going to get my hopes up, I will only be convinced that this problem is resolved if the car does not act up for several days, and after some long trips.

so stay tuned!! if this is indeed finally fixed, i will come back to this thread and make a "conclusions" post, outlining what the problem was, what i did to the car, and my theory as to how it got fixed.

monty23psk · « **Reply #107 on:** October 07, 2009, 08:15:37 PM »

Awesome. When I took my 10 minutes drive, the car was at operating temp, between 1/4 and 1/2 within 5 minutes. Very warm today. And after the 12 minuted ride, lower hose is boiling hot.

To answer you first posting of tonight. Your radiator is fine. After driving awhile, since the engine is hot, the temp will start to climb. And only when you accelrate, does the fan clutch kick on, and the water pump spins more to produce flow, hence the hose getting hot.

Let us know how it goes the next couple of days.

iamcreepingdeath · « **Reply #108 on:** October 07, 2009, 08:59:56 PM »

BTW i have no fan clutch. I am rocking the Volvo electric puller fan in place of the stock fan, clutch, and shroud.

monty23psk · « **Reply #109 on:** October 07, 2009, 09:53:18 PM »

Then the fan should be cooling it enough to compensate for the missing fan clutch. Is it on all the time? Also the flow is still rushing becasuse the water spins faster when you accelerate.

iamcreepingdeath · « **Reply #110 on:** October 07, 2009, 10:02:01 PM »

yeah the fan works fine. it runs at a constant speed all the time, and kicks in to high if the temp in the rad gets high enough, which it never does. That issue was addressed a long time ago.

i guess the issue was the t-stat and the rad being clogged.

monty23psk · « **Reply #111 on:** October 07, 2009, 10:04:23 PM »

Cool. I have the Spal in front of the condensor with no fan clutch. If it goes on low or high, my temp actually goes done. But if I am in rush hour, it will keep it from going pat 3/4 on low. If high gets on, it will kick it down to 1/2. And imagine, the air from the fan has to go thru condensor and radiator. But I do have a shroud. I would recommend if the volvo ever dies.

iamcreepingdeath · « **Reply #112 on:** October 07, 2009, 10:18:09 PM »

yeah i have no AC condenser, i ripped all my AC stuff out, including all the lines and the compressor, because the compressor is seized up, and i would have to pay an arm and a leg for a new compressor, and then convert to r134a on top of that, and it wouldn't be worth it.

If the Volvo fan ever takes a poop i am definitely getting a Spal pusher to strap right to the front of the radiator. Heck i'll be doing that anyway when i eventually do my S50 swap...

johnwoo · « **Reply #113 on:** October 08, 2009, 01:40:56 AM »

Quote from: monty23psk;79579

Awesome. When I took my 10 minutes drive, the car was at operating temp, between 1/4 and 1/2 within 5 minutes. Very warm today. And after the 12 minuted ride, lower hose is boiling hot.

To answer you first posting of tonight. Your radiator is fine. After driving awhile, since the engine is hot, the temp will start to climb. And only when you accelrate, does the fan clutch kick on, and the water pump spins more to produce flow, hence the hose getting hot.

Let us know how it goes the next couple of days.

so what do you guys think is wrong with mine. it take forever for that hose to warm up. i have new radiator water pump and tstat. 88 temp. do you think my rad is clogged? hmm..im gonna do some overhaul on my sensors then see if that will fix it. my car just be running lower than the 88 degree temp of the tstat for it to warm up.

monty23psk · « **Reply #114 on:** October 08, 2009, 09:18:30 AM »

If the hose take forever, either tstat is not allowing a lot of coolant through or you have a blockage. One option is to remove tstat and see if the hose gets hot after driving it a while and letting the temp get up on the engine. If you radiator is new, I would not think that it is clogged.

John, I know I have been following iamcreepingdeath issue closely. What exaclty is yours?

Also, I just replaced the top hose on mine yesterday and didnt bleed it. I noticed driving to work that the car temp is hotter than normal. Stays at the noon instead of the half past 1/4. So I know I have air and need to bleed. M42 is picky when it comes to coolant and air. The engine itslef carrys very little coolant compared to the m20 for example. So any little air goes a long way.

johnwoo · « **Reply #115 on:** October 08, 2009, 11:26:59 AM »

well my issue on my car is

my needle bounces around from 1/2 to 3/4. similiar to dancing needle so i have to check my ground. also the hose on the passenger side as marked in th pic takes forever to warm up. i've bled the system forever. im gonna do the lower temp tstat check the ground on my cluster, and change the sensor on the head. then prime the hose by filling it. so hopefully i get my issure resolved. the hose does eventually get hot.

my gauge if hit also goes back down to halfway mark. im just tired of driving the car with one eye on the temp gauge. the m20 that i have sits dead square on the 1/2 mark.

iamcreepingdeath · « **Reply #116 on:** October 08, 2009, 12:02:57 PM »

johnwoo: do the ground thing on the back of the cluster like you said, and then with the car all the way warm and the heat on, try bleeding it again. This time don't look for bubbles, jut open the coolant tank and fill it to the brim with coolant, and then unscrew thhe bleed screw a little, and then hold the engine at like 3k rpm until the coolant level drops to the cold mark.

This way you are just pushing alot of coolant out of the bleed screw, and it ought to bleed the system. Also, did you put the t-stat in with the arrow pointing up?

monty23psk · « **Reply #117 on:** October 08, 2009, 03:54:33 PM »

Sounds like you might be ok, just a temp gauge issue. Also depends on exterior temp and how long the tstat takes to open would the lower hose gets hot. If it is, then I think tstat is ok. Having the aux fan and fan clutch also help out in case you are at idle.

Hondo · « **Reply #118 on:** October 08, 2009, 09:47:28 PM »

It appears this problem may have been solved.
Once upon a time, I had a car doing this, bleeding coolant, gauge all over the place. It turned out to be a bad head gasket. There was no white smoke, no coolant in oil. Exhaust gas was going into the coolant. It was a pretty strange problem, that went away after I changed out the head gasket.

iamcreepingdeath · « **Reply #119 on:** October 08, 2009, 10:08:22 PM »

Quote from: Hondo;79650

It appears this problem may have been solved.
Once upon a time, I had a car doing this, bleeding coolant, gauge all over the place. It turned out to be a bad head gasket. There was no white smoke, no coolant in oil. Exhaust gas was going into the coolant. It was a pretty strange problem, that went away after I changed out the head gasket.

i sure hope i don't have to do my head gasket.