White93z34 Posted April 3, 2007 Report Share Posted April 3, 2007 on a 92' GPSE 3.1/4t60 JUST replaced radiator upper and lower hoses water pump thermostat radiator cap basically the cooling system will not get up to pressure, and for the life of me i do not know why. also the fans do not work. they will work with the car in diagnostic mode with a paper clip in the ALDL, but will not come on when they are supposed to. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 3, 2007 Report Share Posted April 3, 2007 this sounds familiar! Quote Link to comment Share on other sites More sharing options...
5speedz34 Posted April 3, 2007 Report Share Posted April 3, 2007 That's weird they come on is diagnostic mode? HMMM. Check them with a 12v powersource and see if they come on. If they do then I would think its not the fans and that maybe something isn't turning them on? I would still replace the WP for shits and since its cheap. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 3, 2007 Report Share Posted April 3, 2007 That's weird they come on is diagnostic mode? HMMM. Check them with a 12v powersource and see if they come on. If they do then I would think its not the fans and that maybe something isn't turning them on? I would still replace the WP for shits and since its cheap. ? the fans are supposed to turn in in diagnostic mode. could the car have a leaking heater core or the feed lines along the side of the engine bay have gone bad? I'd change the temp sensor for the ecm chris Quote Link to comment Share on other sites More sharing options...
slick Posted April 3, 2007 Report Share Posted April 3, 2007 Well... with the cooling system not building pressure, I'm not suprised the fans aren't turning on. Is there just an insane amount of air in the system, or whats the deal? Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted April 3, 2007 Report Share Posted April 3, 2007 Well... with the cooling system not building pressure, I'm not suprised the fans aren't turning on. Is there just an insane amount of air in the system, or whats the deal? Yeah, when I did my water pump a few months ago it took like 30min to get all the air out of the system. But, if it's not holding pressure there is a leak somewhere. Quote Link to comment Share on other sites More sharing options...
slick Posted April 3, 2007 Report Share Posted April 3, 2007 Wow, thats crazy. I knew these cars were a pain to get air out, but that bad? Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 3, 2007 Report Share Posted April 3, 2007 Its not that big of a deal to bleed the system of air. I did it in about 5 minutes when I changed the radiator on my car.... Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted April 3, 2007 Report Share Posted April 3, 2007 Wow, thats crazy. I knew these cars were a pain to get air out, but that bad? Yeah, start it up, watch temp gauge in the car hit 220 rather quickly, shut down, start up, watch temp gauge, shutdown, etc, all while opening the bleeder valve. Even when I swapped out radiators this summer bleeding it didnt take as long as it did with the water pump. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted April 3, 2007 Report Share Posted April 3, 2007 Its not that big of a deal to bleed the system of air. I did it in about 5 minutes when I changed the radiator on my car.... I know, I was just saying it seemed like bleeding it after doing a water pump took much longer than any other repair that requires bleeding. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 3, 2007 Report Share Posted April 3, 2007 Wow, thats crazy. I knew these cars were a pain to get air out, but that bad? Yeah, start it up, watch temp gauge in the car hit 220 rather quickly, shut down, start up, watch temp gauge, shutdown, etc, all while opening the bleeder valve. Even when I swapped out radiators this summer bleeding it didnt take as long as it did with the water pump. You shouldnt be opening the bleeder vlave when the car is running... But yeah I thnk the worst part to bleeding it is getting coolant everywhere Quote Link to comment Share on other sites More sharing options...
slick Posted April 3, 2007 Report Share Posted April 3, 2007 I always crack my bleeder valve, then turn the car on. Doesn't seem like the car would bleed properly without the engine running since the water pump wouldn't be moving any of the coolant and possible air around the system. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 3, 2007 Report Share Posted April 3, 2007 I always crack my bleeder valve, then turn the car on. Doesn't seem like the car would bleed properly without the engine running since the water pump wouldn't be moving any of the coolant and possible air around the system. The reason it wouldnt bleed right is because everybody just starts it up and lets it idle. Thats not good enough to get some of the pockets of air to move around. You need to crack the throttle a couple times/ use more of the rpm range. The bleeder isnt suppose to be open when running because that doesnt seal the system. Quote Link to comment Share on other sites More sharing options...
slick Posted April 3, 2007 Report Share Posted April 3, 2007 Yeah, I always hit the throttle with my hands when bleeding the system out. After I have what I think is pretty good, I shut it off, and let it cool for a few minutes. Then, I open the rad cap, and with the bleeder valve still open, add more until it's just coming out of the bleeder valve what I'm adding. Generally then, I know I"m good. Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 3, 2007 Report Share Posted April 3, 2007 What I usually do, is the small coolant hose from the WP that goes underneath the plenum. I use that and a funnel to fill it until I get coolant coming out both bleeders. Then I just run the car for a while, let ot cool off, then run it again, let it cool off and the add any if needed and Im done. Quote Link to comment Share on other sites More sharing options...
White93z34 Posted April 3, 2007 Author Report Share Posted April 3, 2007 i should also mention that the car has not been able to build pressure before this hapening. Quote Link to comment Share on other sites More sharing options...
slick Posted April 4, 2007 Report Share Posted April 4, 2007 Oh damn. BHG? Quote Link to comment Share on other sites More sharing options...
White93z34 Posted April 4, 2007 Author Report Share Posted April 4, 2007 alright i pissed around with it earlier, put the laptop on it, the CPS was reading correctly. everything seemed right. ended up hooking up the fans again, waited till about 230F and the primary kicked on and droped the temp back to normal. why it wasen't doing this the other night is beyond me i made sure the fans cycled properly some 5 times before calling it good enough. the system does hold a little pressure, but not all that much. so lord knows, but for now it seems just ducky. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 4, 2007 Report Share Posted April 4, 2007 chris. I want your mad skilz with a laptop to determine WTF is up with my ride! Quote Link to comment Share on other sites More sharing options...
White93z34 Posted April 4, 2007 Author Report Share Posted April 4, 2007 chris. I want your mad skilz with a laptop to determine WTF is up with my ride! you have that bastard child OBD 1.5 on your troublesome cutlass, only a tech1/2 can save you! Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 4, 2007 Report Share Posted April 4, 2007 chris. I want your mad skilz with a laptop to determine WTF is up with my ride! you have that bastard child OBD 1.5 on your troublesome cutlass, only a tech1/2 can save you! OTC scan tools Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 4, 2007 Report Share Posted April 4, 2007 chris. I want your mad skilz with a laptop to determine WTF is up with my ride! you have that bastard child OBD 1.5 on your troublesome cutlass, only a tech1/2 can save you! OTC scan tools say what? Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 4, 2007 Report Share Posted April 4, 2007 chris. I want your mad skilz with a laptop to determine WTF is up with my ride! you have that bastard child OBD 1.5 on your troublesome cutlass, only a tech1/2 can save you! OTC scan tools say what? OTC makesa scan tool that you can plug in to the OBDI port, and veiw ALL SYSTEM stats. You can pretty much control/monitor everything that the computer controls. Ill have to ask my dad if Im able to change specs/stats with it. Since we have the tool, I can pretty much do what I want/ find out what I want about the "OBDI.5"... Quote Link to comment Share on other sites More sharing options...
gp90se Posted April 4, 2007 Report Share Posted April 4, 2007 Chris..Go down to your local pimp caddy dealer, go ask the parts counter for the cooling system sealer they use in their cars. If it has a leak, that shit will seal it up. If it doesnt have a leak, it will only settle in the block and not the heads/heater core. Quote Link to comment Share on other sites More sharing options...
RJansen658 Posted April 5, 2007 Report Share Posted April 5, 2007 If the system will not generate pressure there are only so many things that will cause it. The #1 all time cause is the radiator cap... either it simply opens at way too early of a pressure, or it never seals correctly in the first place. There have been many many times where I replaced either a rad or a cap, and since one of them was aftemarket, they simply did not seal together properly. Sometimes the cap will seal up the radiator great, but the lower seal doesn't seat to seal the radiator from the overflow, thus the system never pressurizes. As for it being an undectable leak keeping it from pressurizing, that is unlikely. ANY leak that would be large enough to keep the system from pressurizing would allow coolant to go on the ground as you fill it. Thats a rule. As a matter of fact, the only way TO find a small leak is to pressuruze the system with a tester, which just goes to show you, it has to be a large leak to keep the system from pressurizing, large enough that it would have to leak everywhere if the system is full. As for the next most likely cause....defective, improperly installed (upside down), or stuck thermostat. Your antifreeze needs to reach its boiling point to generate pressure. If it doesn't it never will pressurize. (I'll explain this better in a sec) Least possible.... you don't have straight antifreeze in it do you? The boiling point of straight antifreeze is so high that if you have a good running engine, or live in a cool climate, your engine may never be able to make it reach the boiling point. And I'm not sure how much you know about the scientific aspect of how the cooling system works, but I am gonna try to explain the principals a bit in case you're not familiar with them. Pressure is kinda double edged in a cooling system... in a way its good. I'll cover that first. Its good, because as liquid pressurizes, it molecules move closer, which raises its boiling point. A higher boiling point means more heat can be absorbed before we get that explosive reaction usually accompanied by a boiling liquid But a liquid won't be pressurized unless it is in a sealed container, like a cooling system, and even then, you need a means of pressurizing it. Different ways of doing this, we do it in spray cans BASICALLY by forcing increased air pressure inside the can thus increasing the liquid pressure of what ever the spray can holds. But we can't use air pressure to increase the coolant pressure in a cooling system, because air will allow the coolant to boil almost instantaneously. Thats the ONLY reason why coolant will come exploding out onto you if you open the cap on a hot system. Don't get me wrong, liquid CAN boil in an airtight system, it just takes a ton more heat. A ton. So if we can't use air pressure, then we will use heat. Since we are applying heat to the coolant, and it is in an airtight system, it can't boil (yet...) so its pressure raises, which also raises its boiling point. So why doesn't it keep raising until it explodes? Well, the engine can only generate so much heat, although it is enough to burst the cooling system. Thus we have the radiator, fans, and thermostat to keep it in a pressure and temperature range that is low enough to be contained in the systems components. Thats the reason most radiator caps are around 16lbs, it apparently is the sweet spot for safe pressure (for the engine anyway), that allows it sufficient cooling capabilites, at an acceptable pressure. Its kinda cool because the heat raises the boiling point all by itself, its an exponential reaction that only limited by the durability of the container and the heat being applied to it. Also, this is all assuming there is NO AIR in the system, so proper bleeding is important. As for when you guys were talking about using the bleeders, when the engine is on or off. The only way to do it is with the engine running, bleeders open, and only after at least 2 thermostat cycles like this will it be bled good. I never shut it off during the procedure. Open bleeders, fill it, start it, top it off, if it burps up, hold the on and let it burp thru the bleeders, keep an eye on it the whole time, and fill it every time it burps, or the stat opens. Once it has opened twice for sure you are done. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.