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08 Alpha. Why so hot???!!!

lfootmatt

Well-Known Member
Messages
81
Location
AZ
It runs like this most of the time unless it's on the highway. Then it drops to just below 5/8th. I know these Alphas are known to run hot, but this is crazy.

Is this normal at 100 degrees outside? Floors radiate massive heat as well.

I'm looking at a severe duty fan clutch, and just throwing on a 16" electric fan I have sitting around on a switch until I can get the dual fan setup copied from Reloader.

Thanks,

Matt
PXL_20220802_051748077.jpg
 

Jeepwalker

Well-Known Member
Messages
611
Location
WI
What are the temps going down the hwy?

I think the first thing to do is establish how hot your engine REALLY is running ...before adding electric fans, etc. There's a strong chance something else is going on. Maybe it's not running hot, but the gauge temp sensor has drifted. The Alphas would have been able to run all day long across a hot AZ, so there must be something else going on. Adding dual electric fans most likely won't cure the problem. It's going to add more drag to your alternator (engine load), and won't allow as much air flow through the radiator. There's no free lunch when it comes to moving air. You might spend a couple hundred bucks and 2 weeks messing with fans and not have solved the problem. Try to get an IR temp sensor read when the reading is high ..say, on your engine's thermostat water housing. See what the engine coolant temp coming out of the engine is. Also read all the coolant temp sensor/s data with a scanner. Autozone can do it if you don't have the scanner.

1) Definitely check your fan's clutch ...that's a great first step. There are youtube videos how to check. You can check it out cold or hot.
2) Are you running an aftermarket 'flex' fan? They usually don't fit right and generally perform worse than a stock fan (but they look cool!).
3) Are there obstructions in front of the radiator? Lights, winch, bug screen, aftermarket items, etc. Those can all reduce airflow
4) Radiator or condenser plugged up? Is the AC condenser or radiator plugged up with a million dead bugs, or mud?? Might pull the radiator and hose the condenser out from the inside ...same with the radiator. Electric fans won't compensate for plugged airflow.
5) The temp sensor (for the gauge) could be flaky. There's usually one sensor for the ecu and one for the gauge.
6) Thermostat may be slightly wonky or only opening up part way, (get an AC Delco one if you replace it).
7) The radiator could be mineral'd up inside if hard water was used (reducing water flow).
8) The lower radiator hose could be 'sucking in' if the spring is gone, or hose is flacid.
9) Is the belt glazed and slipping? Probably not, but you gotta check all avenues.
10) Head gasket could be failing. No external fans will solve the overheating affect of a leaking head gasket. It doesn't take long to diagnose a failing head gasket (milky substance under oil fill cap, gurgling heater core on morning start-up, bubbles and combustion smell in radiator, spark plug super-clean, etc). A head gasket can be in a failing state literally for years before they finally 'let go'. Often layers of the head gasket material can delaminate ..and allow slight leakage. But they can cause overheating. If you detect anything like this fix it asap before it kills your catalytic converters.
11) Running too rich? You didn't mention check engine lights, but just throwing out all options: an engine running out of spec can cause higher temps.
12) Exhaust restriction? - Again just throwing out all potential items to put on your check-list of items to look at.
13) Is the current fan in the right position? If everything is stock then this shouldn't be a problem. But if the engine cooling fan is too far forward/rearward, etc it won't pull as much air as it should. Also if any of the fan shroud is broken or missing, that will reduce airflow.
14) Does the fan shroud fit tight around the radiator? Again, if it's all stock this shouldn't be an issue. But if it's been messed with and a smaller fan is on it or the shroud is cut or broken, it could be sucking air from the side and not 'through' the radiator.

That's about all I can think of at the moment. Check these things out before you spend a bunch of time with electric fans. Let us know what you find
 
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650Hawk

Well-Known Member
Messages
387
Location
SoCal
Great list of things to check. I live in SoCal and my '08 Alpha seldom gets above the 1/2 mark, even in the summer. Although you need to get an actual temp reading. I use the Torque app with an OBD dongle; rarely see over 205 degrees, usually at 195-200.
 

cgalpha08

"Like Nothing Else"
Messages
3,503
Location
Indianapolis, IN
Get a scangauge or something similar to tell you what the actual engine temps are. The dash gauge is more of a dummy gauge and isn't really a good representation of where it should be sitting. plus i think somewhere along the line they adjusted the thermostat (GM did) to get the gauge to sit at half, someone else can confirm.

For example on mine, the needle stays at half and actual temps read 193-195 ish.

That being said it could also be anything the jeepwalker mentioned ,but i would atleast get a true reading first before doing anything else.
 

JPaul

Well-Known Member
Messages
2,356
Location
Way up north, UT
At 100 degrees ambient, I wouldn't be surprised to see it that high, especially if you're blasting the AC. For mine the 3/4 mark is about 220 degrees which is not abnormal when running AC in that high of temps. Even with the AC broken and I was towing a small trailer in 100 temps I was getting upwards of 230-232 degrees F, which still only put the gauge a little above the 3/4 mark.

As others have mentioned you really need to put something on that will give you the actual readout instead of just relying on the gauge. Scangauge is fine, though I prefer my Ultragauge to be honest. Even just using a dongle or a OBD2 scanner with readouts can tell you. I wouldn't worry too much about it to be honest. I only sit around half (195-210F) when driving in cooler weather without any real loads (AC/towing).
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Well, that all makes me feel better, but it just still feels like it runs so damn hot.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Okay, so at 106 F ambient, probably 110ish in the O'Rileys parking lot idling with the AC blasting the scan tool showed 232 F with a few extra RPMs dropping to 230 quickly. Temp gauge showed a hair over 3/4. So technically not over heating, but way too darn hot for my taste. AC labored a bit at idle and quickly recovered once under way. Downright icy cold on the highway at 70-75 mph. Temp gauge dropped to a hair over 5/8 when coasting up the off ramp after 10 minutes ay 75.

We're changing the oil and trans fluid tomorrow. so I'm going to slap an 16" electric pusher fan in and see if that helps. Trans cooler, and new perhaps a 190 T-stat for experimentation in the near future.

So technically not overheating, but running too darn hot for me.

Thanks,

Matt
 

alrock

El Diablo
Staff member
Messages
10,121
Location
Scottsdale
That's pretty much how my I5 has been running, hot when parked in AZ with a/c on, fine times on the road. I replaced the fan clutch recently even though the old one hadn't technically failed. But I've only driven about 40 miles since then so I can't verify if that fixed it. But it didn't used to get that hot when idling. Since mine didn't act like that before, and cools down fine on the road, to me that said my fan clutch was not operating properly.

But I'd also double check that the shroud is intact like mentioned above. The I5 has a slip shroud where the bottom slides around to the top when removing it, but I don't think the Alphas do. Make sure no one cut it up to make removing it easier.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Thanks alrock! I'll check that stuff. I was going to get a severe duty Hayden Fan clutch just in case. Ran one in the hot months for years in my 3/4 ton 8.1 L Suburban. It downright roared because it moved so much air.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Also.... Any ideas on the best place to jumper in a 16" electric pusher fan. Mostly as a temporary test to give it a bit more air, but I'd rather not burn the truck down in the process. I already have the old light bar switch and wiring I may use, but I'd feel better coming off a relay.

Thanks,

Matt
 

alrock

El Diablo
Staff member
Messages
10,121
Location
Scottsdale
I have one of these on my firewall with a connection straight to the battery, and relays as needed. Of course that implies a more complete wiring job but your in-cab switch doesn't need permanent mounting yet.

I tapped into the 12V lines for the accessory outlets for my lockers. Those outlets power my switches through a relay and the relay is powered off of the Blue Sea fuse block.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Long term, I'll go through a relay. Probably just go through an accessory fuse we dont use much. Heated seats.... No use for those here in AZ until February🥶
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Okay, so we shoehorned in a 16" electric fan, well sort of. It's jammed in on the passenger side of the of the cavity but not up against the evaporator core. It's more toward the front up against the grill, 6ish inches away from the evap core. Just on a switch with a 15amp fuse in line off the battery grounded to the body. Didn't think it would do much. Wrong, worked like a charm. Same test run at 104 F versus 106, temp gauge never got over 5/8, scan tool was at 210 - 212 F and holding while idling with the AC blasting icy cold air. Yesterday, it was at 235 F and rising with struggling AC. While it certainly isn't pushing a ton of air through the evap core and radiator it is pulling in tons of cooler outside air that the mechanical fan then pulls through.

I'll post up some pics later. its very redneck and the wiring is a bit comical as this was a low effort test. We'll work on a more permanent plan. I may go with the same concept using a slightly smaller fan that fits better with similar CFM to pull in cooler outside air, severe duty mechanical fan clutch, and perhaps a second smaller electric fan pushing the fresh air through the same side of the evap core and radiator. I'll probably factor in a tranny cooler as well. Because who doesn't like a cool tranny!

Oil change, went 5w40 instead of 5w30 due to the higher ambient temps and how hot the truck runs. Used our fluid vac to empty the trans pan and refill with fresh fluid, same with the power steering tank. Old tranny fluid was nasty, more brown that I'd like to see. We'll vac the tranny and PS several times this week to get some fresh fluid in there. Tranny pan drop and filter change in the near future.

Later and thanks all!

Matt
 

Guerrero

Well-Known Member
Messages
121
Location
Spain
It runs like this most of the time unless it's on the highway. Then it drops to just below 5/8th. I know these Alphas are known to run hot, but this is crazy.

Is this normal at 100 degrees outside? Floors radiate massive heat as well.

I'm looking at a severe duty fan clutch, and just throwing on a 16" electric fan I have sitting around on a switch until I can get the dual fan setup copied from Reloader.

Thanks,

Matt
View attachment 30973

Hello there!


Talking from Spain but a lot of experience with H3 cooling system in both i5 and v8


First of all, yes, that is hot (not overheating) but hot. I read your last reply, if you are getting lower temps with a 16 inch pusher, definetly your clutch fan is failing. 16 inch pusher doesnt push enough air to cool down, so if you notice a difference, that is because your puller (clutch fan) is not good, so my list would be:

-Replace coolant (flush with distilled water and later add a 30% organic coolant if you live in a hot climate area, if not then 50% coolant.
-Add a bottle of Motul Moccol additive to coolant or Lucas Supercoolant (this will help a lot, most in heavy use situations)
-Replace thermostat. If you want to see 1/2 gauge that is 192-193 F. The best is a 180ºF thermostat (GM is 195ºF so choose another brand) or even better (is my application now) 174ºF LINGERFELTER thermostat.
-Change clutch fan, directly, i know is costly but more costly is to replace engine.
-Clean radiator completely, from outside and remove all the mud and dust of the fins. Is better to remove radiator from the Hummer and clean it out.


With these five steps you will recover 1/2 of gauge always. Remember to change water pump if your mileage is 100.000 miles or more since last replacement of the water pump.


A lot of people consider H3 stock cooling system capacity is not enough. That was not my experience, even in sahara desert, even at +100 F ambient temps. They are barely enough but if you open the restrictions (airflow and flow of coolant (lower temp thermostat) you can achieve great resuls.

A coolant that transfer better the heat will help also. Because water is the best heat transfer. The higher % of coolant, the worse the heat transfer. But you need a setup that could hold the freezing temps in winter. So I chose in Spain 30% coolant and a bottle of Motul Moccol.

If you have lot of accesories in the front reducing airflow, and healthy clutch fan, good coolant and additive, 174ºF thermostat and still getting hot under some circunstances, maybe good next move is a dual core radiator. But I am trying to avoid it in my alpha.

I am installing now a Camaro SS fan (850 watt brushless 19 inch efan producing more or less 5000 cfm) replacing the dual efans that replaced my stock clutch fan. I always want a efan setup for mpg and power, but in the alpha the ideal is the stock clutch fan (9000 to 12000 cfm engaged at high rpm). If I get a 1/2 gauge with Camaro SS and stock radiator even in Sahara desert under 100+ F ambient temps, that will be the proof that stock radiator could handle the cooling of the Alphas. I will report when I test the new setup


Best
Óscar Guerrero
 
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lfootmatt

Well-Known Member
Messages
81
Location
AZ
Thanks Oscar! You pretty much hit where I was going with this cooling system. I'll have to look at the freezing point of 30% coolant. We are a pretty quick drive from the mountains and potential freezing conditions in the winter.

If I can find one, a Hayden severe duty fan clutch is going in. Out of stock most everywhere. My old 3/4 ton 8.1 suburban literally roared in the summer months with the SD fan clutch. I may still go with a supplemental electric fan for the summer months.

How thin is that Camero SS fan? Must be very thin! There isn't much space between the vertical hood latch brace and the evap core.

Thanks again!

Matt
 

Doc Olds

Well-Known Member
Messages
72
Location
Boat Town MI
Hey fellas, haven't been over here in a LONG while. Thought I would stop by.

At 100F+ I would call 3/4 on the dash idiot gauge normal. Biggest cause for inefficient cooling in the H3s is the old dirty Radiator/Condenser problem. Rinse thoroughly from both sides then see what it does. My 09 Alpha was from Arkansas and had all kinds of bugs and crud stuck in between the Radiator and Condenser down near the bottom. Took the front end apart when I did the cam swap it and made sure to clean those like crazy.

Follow the other good ideas already posted as well.

Pusher fans help at low speed like wheeling or idle, but can actually reduce flow at highway speed unless they push hard enough to keep up with 55-70 MPH air pressure. Just keep that in mind.

Keep on Truckin
 

EndeavoredH3

Well-Known Member
Messages
255
Location
Arizona
For me, I have the OD 1.25” body lift. So my fan shroud was rotated out of the way (until my fan decided to take it out) and there was the gap on the upper moon of the shroud. Point is, my fan doesn’t draw airflow through the core like it used too. Paired with a severe duty fan clutch I can run between 204-213 with AC on on the freeway. In town I suffer from heat soak and it’s between 210-225. Sometimes I put it in 3rd to get some more airflow and to spin the water pump a bit more.

I’ve been looking into the various radiator options that have come about recently. As before we only really had GM, Aftermarket factory style, and csf (prone to leakage, if not then good for you!)

There has been an abundance of 2-3 core Colorado radiator options on Amazon/eBay and of course the ecp H3 radiator. Was thinking an increase in capacity would warrant use of an electric fan if the clutch fan won’t clear a thicker radiator. The increase in capacity would help with the H3 cool for both the I5 and V8 applications.

Read back a few posts from threads older than time itself and the rave back in the day was to relocate the thermostat to the upper radiator hose. I hadn’t seen any cons and frankly, people blew up their i5’s before they could test for long term. James and I @ PHR are talking about making a bolt on thermostat relocation kit, I’m curious to see how it’d perform. And I’m in a good geological location to give it a good test
 

EndeavoredH3

Well-Known Member
Messages
255
Location
Arizona
Thanks Oscar! You pretty much hit where I was going with this cooling system. I'll have to look at the freezing point of 30% coolant. We are a pretty quick drive from the mountains and potential freezing conditions in the winter.

If I can find one, a Hayden severe duty fan clutch is going in. Out of stock most everywhere. My old 3/4 ton 8.1 suburban literally roared in the summer months with the SD fan clutch. I may still go with a supplemental electric fan for the summer months.

How thin is that Camero SS fan? Must be very thin! There isn't much space between the vertical hood latch brace and the evap core.

Thanks again!

Matt
I’m using an autozone severe duty clutch. It’s been surprisingly reliable for 2 years now.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Hey fellas, haven't been over here in a LONG while. Thought I would stop by.

At 100F+ I would call 3/4 on the dash idiot gauge normal. Biggest cause for inefficient cooling in the H3s is the old dirty Radiator/Condenser problem. Rinse thoroughly from both sides then see what it does. My 09 Alpha was from Arkansas and had all kinds of bugs and crud stuck in between the Radiator and Condenser down near the bottom. Took the front end apart when I did the cam swap it and made sure to clean those like crazy.

Follow the other good ideas already posted as well.

Pusher fans help at low speed like wheeling or idle, but can actually reduce flow at highway speed unless they push hard enough to keep up with 55-70 MPH air pressure. Just keep that in mind.

Keep on Truckin
Hmmmm, Doc Olds, any shot you're a Classic Olds or ROP forum guy??? Sounds familiar... I was mostly an ROP guy for years before the various crashes. So much institutional knowledge was lost.

The Radiator and evap cores are pristine as the entire AC System was just replaced. I think an new HD clutch will do the trick. 128K miles so the factory fan clutch is probably shot. I'll probably also add a high volume pusher fan as well to aid with the low speed/traffic/wheeling situations. The AZ hear is brutal at times.

Thanks guys!

Matt
 

EndeavoredH3

Well-Known Member
Messages
255
Location
Arizona
Hmmmm, Doc Olds, any shot you're a Classic Olds or ROP forum guy??? Sounds familiar... I was mostly an ROP guy for years before the various crashes. So much institutional knowledge was lost.

The Radiator and evap cores are pristine as the entire AC System was just replaced. I think an new HD clutch will do the trick. 128K miles so the factory fan clutch is probably shot. I'll probably also add a high volume pusher fan as well to aid with the low speed/traffic/wheeling situations. The AZ hear is brutal at times.

Thanks guys!

Matt
Pusher fan helped chill my AC a little more in July at stoplights.

And wow 128k on a fan clutch, I never got more than 20k out of any clutch.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
128K, but its probably been shot for 100K.... Who knows! Gotta get it done and finalize my electric fan plans.
 

lfootmatt

Well-Known Member
Messages
81
Location
AZ
Any thoughts on perhaps an upgrade to the water pump while I'm in there doing the fan clutch?

I've seen various claims online, flowkooler, speedmaster... What's the consensus out there on their ability to increase cooling for a 5.3L. Or... does increased flow hurt by decreasing dwell time of the coolant both in the block and in the radiator and possibly hurt the cooling ability of the system. So much conflicting info out there!

Thanks,

Matt
 
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