Over heating in town with A/C on
#1
06-02-2017, 08:17 PM
Over heating in town with A/C on
Hey guys, got a bit of a mystery to me here. Maybe someone can help with a clue or shed some light somewhere.
2000
Blazer
2000
Blazer
4 Dr4wd
4.3
New water pump, radiator and thermostat with an engine block flush done on memorial day.
Symptoms are:
Like the title, the truck is good until run the A/C. BUT it's still good at highway speeds and if the ambient air is 82° or less. It's only when the ambient temperature is 83° or above with A/C on at all, it will run down the highway all day long. When you hit town speeds of 35mph it climbs to 210. I'm OK with that but as soon as you stop for a light or even slow down to pull into a parking lot, it starts climbing quickly to 240° and will keep going until you either
A: turn off A/C
B: start moving 40mph+ then it cools right down.
C: do both
Coolant is full, clean and flowing very nicely.
Fan clutch stops about 1/2 turn after shut engine off. So I don't believe it's that but it's the only thing I can think to throw at it or switch to electric fan.
Below 82° ambient air temp you can sit and idle all day long with A/C on max and it won't move past about 195ish. That's great and all but we have 100° days coming soon and 1/2 my commute home is thru town. I'd really appreciate being able to run the A/C. Lol
If anyone has had anything like this, and fixed it, I'd love to hear that. But if anyone has anything, I'm open to any ideas.
Thanks In advance!
4.3
New water pump, radiator and thermostat with an engine block flush done on memorial day.
Symptoms are:
Like the title, the truck is good until run the A/C. BUT it's still good at highway speeds and if the ambient air is 82° or less. It's only when the ambient temperature is 83° or above with A/C on at all, it will run down the highway all day long. When you hit town speeds of 35mph it climbs to 210. I'm OK with that but as soon as you stop for a light or even slow down to pull into a parking lot, it starts climbing quickly to 240° and will keep going until you either
A: turn off A/C
B: start moving 40mph+ then it cools right down.
C: do both
Coolant is full, clean and flowing very nicely.
Fan clutch stops about 1/2 turn after shut engine off. So I don't believe it's that but it's the only thing I can think to throw at it or switch to electric fan.
Below 82° ambient air temp you can sit and idle all day long with A/C on max and it won't move past about 195ish. That's great and all but we have 100° days coming soon and 1/2 my commute home is thru town. I'd really appreciate being able to run the A/C. Lol
If anyone has had anything like this, and fixed it, I'd love to hear that. But if anyone has anything, I'm open to any ideas.
Thanks In advance!
#2
06-02-2017, 10:29 PM
My first educated guess is a failing fan clutch. It's at least simple to swap for a new one.
Not sure where exactly you live, but here in hot humid Florida, one of the first things I did to my 04 when I got it (aside from replace the ENTIRE AC system) was install Intrepid electric fans. Hands down the best thing I've ever done to the Blazer.
Not sure where exactly you live, but here in hot humid Florida, one of the first things I did to my 04 when I got it (aside from replace the ENTIRE AC system) was install Intrepid electric fans. Hands down the best thing I've ever done to the Blazer.
#5
06-29-2017, 08:14 AM
My first educated guess is a failing fan clutch. It's at least simple to swap for a new one.
Not sure where exactly you live, but here in hot humid Florida, one of the first things I did to my 04 when I got it (aside from replace the ENTIRE AC system) was install Intrepid electric fans. Hands down the best thing I've ever done to the Blazer.
Not sure where exactly you live, but here in hot humid Florida, one of the first things I did to my 04 when I got it (aside from replace the ENTIRE AC system) was install Intrepid electric fans. Hands down the best thing I've ever done to the Blazer.
sorry got side tracked on other problems with this thing. So this went to back burner. I did find a slight leak at thermostat housing and haven't had any problems since. Wasn't low on coolant, just sucking air in I guess I can't explain it. But this thing has been like this every step of the way to getting it to a dependable ride. Now it just jumps to 220ish after shut it off. Cools right down as soon as you start it.
Blazin ref 4x4, I am interested in these fans. Live in Missouri so not as hot as Florida but still deal with humidity. I maybe doing the AC system soon too. When using it it seems to create excessive drag. Have to give it an excessive amount of gas to maintain speed. But it is cold! Well cold-ish Lol not the coldest air I've ever felt but think it's in the heat box. With air off there is always heat coming out. So it's dropping it the 40°, it's just warmer air to cool. Anyway, is this a kit for blazers? where did you get yours? I prefer electric over mechanical anyway. Is this a single electric or dual?
Thanks again guys. Hoping to make this a dependable daily driver and road trip rig soon.
#7
07-09-2018, 07:28 PM
Update:
Fought this issue sparaticly even after replacing the fan clutch. Recently some other symptoms started, first a rattle in exhaust at idle. Sounded like a heat shield, wasn't worried about it., Then a whistle after 2800 rpm and lacking enough power to climb to drive. Would have to let off to shift then slowly accelerate. Things got worst as it wouldn't accelerate at all. I was afraid it was busted intake, intake gasket, head gasket, head, cracked block or something. Put it in the shop anticipating a full engine replacement. Luckily they found that the catalytic converter had come apart.
Answers the rattle, the whistle I guess, the lack of power. But also solved the over heating and the occasional loss of oil pressure at idle. (Didn't fix oil pressure, it's still low, but maintains 10psi +10 for every 1000) but anyway, with catalytic converter replaced, no longer boggs with ac on, has plenty of power for cruising highway, no longer over heats unless it's 107° and leave it running for 20 mins. Lol
This was probably the very least likely scenario but if someone has done everything else and still plaqued. It took a year before any of the other symptoms showed up so might be worth investigating.
Fought this issue sparaticly even after replacing the fan clutch. Recently some other symptoms started, first a rattle in exhaust at idle. Sounded like a heat shield, wasn't worried about it., Then a whistle after 2800 rpm and lacking enough power to climb to drive. Would have to let off to shift then slowly accelerate. Things got worst as it wouldn't accelerate at all. I was afraid it was busted intake, intake gasket, head gasket, head, cracked block or something. Put it in the shop anticipating a full engine replacement. Luckily they found that the catalytic converter had come apart.
Answers the rattle, the whistle I guess, the lack of power. But also solved the over heating and the occasional loss of oil pressure at idle. (Didn't fix oil pressure, it's still low, but maintains 10psi +10 for every 1000) but anyway, with catalytic converter replaced, no longer boggs with ac on, has plenty of power for cruising highway, no longer over heats unless it's 107° and leave it running for 20 mins. Lol
This was probably the very least likely scenario but if someone has done everything else and still plaqued. It took a year before any of the other symptoms showed up so might be worth investigating.
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