Clutch Fan to Electric Conversion, 1997 Suburban

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
Just had the idea about that today as a possible fix for poor AC cooling in town. Once it's on the road it's fine, it's just the low airflow at stoplights and low speeds where it's not good enough. Sort of wondering if anyone's done it with good results, or if that'd be a thing worth trying. And maybe a brand recommendation, if there are multiple options,.

It's got an auxiliary transmission cooler, and maybe an engine oil cooler too (I know there's at least one in the radiator; not sure if it's actually in front of it or not), and so I'm thinking some more cfm at idle and so forth would help. If it'd just be similar cfm in a different package, I wouldn't bother. Radiator's only a few years old, and when I've checked the refrigerant charge (not recently), it's been fine.

Also not sure if the wiring'd be a big deal or not. Just searching briefly I saw one set of 2 that pulled 50 amps. I'd hope something sold as a conversion would have some instructions about that.
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,695
I don't know about conversions for Suburbans but do you have the full fan shroud installed?
Also, you should be able to check the fan clutch.
With the motor hot and the engine off try and turn the fan.
It should not slip if the viscous coupling is working properly.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,567
Why not fix the clutch fan. The thermal clutches go bad. The engine driven fan will move 4-5 times the air that any electric fan can move
 

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
Full shroud's there. Fan has virtually no freewheel cold; will check next time it's hot. Don't know what the AC system would need unless it's low; last time I checked it had enough or almost too much charge according to a cheap gauge.
It's got the 1 year warranty compressor, and that was put on 10 years ago.
 

Redrig

Master Chief Petty Officer
Joined
Oct 13, 2009
Messages
849
Yeah , seriously check the fan clutch . I just went through this in my bronco .

I was contemplating this exact thing ....got a new fan clutch and I am moving way more air . AC is cooling better and engine is cooler on long steep grades.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,967
Is the AC Compressor Short Cycling?
Maybe there is a bunch of stuff that made it thru the Condenser, and has taken Residence on the Front of the Radiator? That can certainly Impede Airflow at Idle and Low Speeds.
 

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
Checked the fan last evening after my wife drove it in 100F+ temps. Same stiffness as when cold - doesn't spin freely at all after I move it.
Don't think the compressor's cycling (like low on charge).
Radiator's not all that old so should be clean, but noticed the trans cooler's taking up a lot of real estate on the RH side of the condenser. No external oil cooler (must just be in the radiator tank).
Condenser could be in better shape but not too bad really.
Might check charge, or just wait a couple months, lol.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,567
Simple pressure check will determine charge. If it runs fine over 25mph, I would swap the fan clutch
 

sangerwaker

Commander
Joined
Jul 29, 2004
Messages
2,013
I had a fan clutch on a Dodge Dakota that was fairly stiff to turn, but still needed to be replaced. Once replaced, AC worked fine. Agree with the others it is likely the culprit if it cools above 25MPH. They're not too expensive in most cases.
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,695
Fan should be very hard to turn when hot.
Compressor probably won't cycle when it's hot out especially at idle.
Like others I'd try the fan clutch. Cheap and easy.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
11,862
There are also different variations of fan clutches available such as normal & severe duty. The SD clutch will improve cooling & A/C performance at the cost of extra noise & a bit of horsepower. We have one on our old ‘98 Grand Cherokee 4.0 and it’s great in hot summer weather & also riding at the beach. The temp never goes over 210* which is normal for the 4.0 & A/C works great.
 

HalfWolf

Recruit
Joined
Aug 19, 2023
Messages
2
Just had the idea about that today as a possible fix for poor AC cooling in town. Once it's on the road it's fine, it's just the low airflow at stoplights and low speeds where it's not good enough. Sort of wondering if anyone's done it with good results, or if that'd be a thing worth trying. And maybe a brand recommendation, if there are multiple options,.

It's got an auxiliary transmission cooler, and maybe an engine oil cooler too (I know there's at least one in the radiator; not sure if it's actually in front of it or not), and so I'm thinking some more cfm at idle and so forth would help. If it'd just be similar cfm in a different package, I wouldn't bother. Radiator's only a few years old, and when I've checked the refrigerant charge (not recently), it's been fine.

Also not sure if the wiring'd be a big deal or not. Just searching briefly I saw one set of 2 that pulled 50 amps. I'd hope something sold as a conversion would have some instructions about that.
I totally get where you're coming from with the AC cooling issue at lower speeds. It's a common challenge, especially during those hot days when you're stuck at stoplights. Your idea of adding an additional electric fan to increase airflow at idle sounds intriguing. It's definitely worth considering, and you're right that some folks have tried similar setups with success.

Since you've got an auxiliary transmission cooler and possibly an engine oil cooler, adding another fan could indeed help manage temperatures more effectively. As for brand recommendations, it's a bit tricky without knowing the specifics of your vehicle, but there are reputable brands known for their cooling products like Mishimoto, Derale, Flex-a-lite, and SPAL. It might be a good idea to check out reviews and compatibility with your car model before making a decision.
 

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
Yeah I was thinking about replacing the clutch fan with an electric setup, not so much adding a fan. That would have to go on the front of all that(?) as there's nowhere else for it. Consensus here seems to be that the clutch fan is better than electric if working properly.

The fan that's on there may be a heavy duty version, Idk; the blades are at a fairly aggressive angle. I don't remember light towing package or the like being part of the V.I.N. codes, but it came with 3.73:1 gears, ltd slip RR axle, and the in-radiator oil cooler. The external trans cooler may or may not be add-on.
 

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
When are you available?

Actually I'm not at all convinced it's bad. As I was saying, it's stiff, even in 100F weather right after driving it. That's the test, right?

It's been a couple weeks or more since I looked at it, and I wasn't looking for it at the time, but I gave it a rev from under the hood and could hear it speeding up with the RPMs. Anyway...
 

Renken2000Classic

Petty Officer 2nd Class
Joined
May 10, 2022
Messages
191
Just did the water pump on this. First time I've seen the fan screwed onto the pump, and couldn't get it off until I sprung for a cheap air hammer (to batter the big nut on the side of the face(s) that would tend to loosen it...). The big crescent wrench and small sledge hammer method didn't work; even with heat and Liquid Wrench.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
47,567
Did you get a new fan clutch? If so, just cut the old clutch off the waterpump
 
Top