Another coolant issue thread... lol

[tokendog]

Hi Nico

I've read the threads on how to bleed your coolant system and I'm not having much luck.

I filled the car with 20/80 coolant mixture and let it run for 15 to 20 minutes, even drove it around the block, and the radiator IS getting very hot but the upper hose is still spongy and able to be squeezed without much effort. It does not seem as though its flowing coolant. I open the radiator cap and I do not see the coolant moving at all.

I've driven it up ramps and opened the radiator cap, hand pumped the upper hose, and it gurgles but I do not see the coolant flowing. I've opened the bleeder screw and it shoots out coolant but still, no movement when I look at the coolant through the radiator cap.

Isn't it supposed to be flowing? Isn't the upper hose supposed to be stiff and hard to squeeze if it has coolant in it?

I do not have my coolant resoivor on the system at the moment so I'm wondering if that is keeping it from pressurizing? Also, can the system pressurize without the radiator cap on? As in being able to see the coolant flowing?

Sorry for all of the questions but this is the last issue I have and then she's drivable...

Thanks!!!

[tokendog]

Anyone able to help me out???

[USMCgetsome]

man sometimes the thermostats aren't worth a crap. I had to do the same thing and i ended up changing thermostats 3 times before i got everything to burp and flow properly. Also, to burp the system you'll have to get the front end very high and keep that rad cap open and just be very patient. May take a few hrs to get it to fill properly. just get it up to temp and run the heater as high as it can go. Let it flow then shut her off and cool back down. Repeat the process untill the coolant level is completely topped off. it's kinda ghey but it works there's also a bleeder screw somewhere.

[tokendog]

well I don't have heat in the car as I capped them off due to the heater core leaking. The coolant system is a parallel flow system and capping them doesn't do anything really as the system is closed when the heater is off any ways.

I let her run for 15-20 minutes and the radiator gets VERY VERY hot but the upper hose is still squeezable (i can pinch in completely closed) and the coolant isn't flowing at all when I look at it...its topped off, but does not appear to be pressurizing or flowing very quickly... I'm going to try revving the engine a few times to see if I can get that to push any air bubbles through...

I've always had issues getting the cooling system to work properly on SR20DETs. Bad luck I guess

[USMCgetsome]

bad thermostat

[tokendog]

What it ended up being is that I did not leave the bleedee screw open long enough. For those with the same issue, put it up on ramps and open the bleeder screw on the water neck. Let the car warm up until the idle drops to like 800 rpm and it stablizes out meaning the t stat opened... You should see coolant gush out of the bleeder hole but don't plug it yet... Rev the engine a couple of times and keep pouring coolant in to the radiator to replace the lost fluid and shake the upper and lower radiator hoses for a good bit. You should see the stream of coolant from the bleeder hole burp and gush a few times during the process but eventually and after you have a large pool of water on your floor, you will only be able to get a steady stream from the bleeder hole...at this point plug the hole, rev the engine some more, and you should see coolant gush from the open radiator cap...at this point you should be ok to cap it off, fill the res tank, and go drive it around a bit so it can pressurize. Stop, check that your upper hose is getting warm, check your temps, and you should be good to go.

Again, do not immediately plug up the bleeder hole when coolant starts to pour out. Keep it open until you can no longer get it to burp or spout out water...it should be an uninterruptable stream of coolant coming out. If you squeeze the upper radiator hose with the rad cap off, all you are doing is sucking in air and that is what is coming out of the bleeder hole. Its ok to do this a few times but mainly you're using the lower hose and the engine revs to get all of the air out.

Also when you open the radiator cap at this point you should be able to hear a hiss as the pressure is released. This process may take a while, it will be messy, and if it takes longer than ten to fifteen minutes I recommend turning the engine off and letting it cool. If you do not have liquid coming out of the bleeder hole or the radiator is not getting hot, be careful, as this may mean your t stat is not opening or something, but it would be signs that coolant is not flowing through the system. Even while I had air bubbles in my system, my radiator was still getting hot, so I knew I had hot coolant from the engine moving a least enough to heat it up a good bit.

Hope this helps someone and thanks for the responses !!!