AC overhaul - Compressor upgrade? Condensor?

BowhunterBrown said:

Anyone have a part number for male pigtail harness for this condensor fan connector?

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Will this one work? It did on mine...
https://www.amazon.com/dp/B000C9MZI4?psc=1&ref=ppx_yo2ov_dt_b_product_details

PlayingWithTBI said:

Will this one work? It did on mine...
https://www.amazon.com/dp/B000C9MZI4?psc=1&ref=ppx_yo2ov_dt_b_product_details

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That looks like the right one! Thank you!

As for wiring it up, I was thinking of using my unused ABS big fuse spot in the under hood fuse block. Then a relay set to ac clutch.

1) What AMP fuse should I use?
2) What amperage relay?

BowhunterBrown said:

I was thinking of using my unused ABS big fuse spot in the under hood fuse block. Then a relay set to ac clutch.

1) What AMP fuse should I use?
2) What amperage relay?

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I'm running the fan and A/C clutch off a 15Amp fuse directly off the battery. I have 2 relays on it - one for the clutch so, when the output from the panel tells it to turn on, the relay gives it full voltage. The 2nd relay for the fan comes on when the clutch is commanded to run AND I'm going under 40 MPH from my EBL but, you may not have that option. You can also hook it up to a Temp Switch that closes when it gets warm - like 170 - 200°, your choice.

PlayingWithTBI said:

I'm running the fan and A/C clutch off a 15Amp fuse directly off the battery. I have 2 relays on it - one for the clutch so, when the output from the panel tells it to turn on, the relay gives it full voltage. The 2nd relay for the fan comes on when the clutch is commanded to run AND I'm going under 40 MPH from my EBL but, you may not have that option. You can also hook it up to a Temp Switch that closes when it gets warm - like 170 - 200°, your choice.

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Sounds like a good setup. But isn't 15 amp undersized? Pretty large gauge wire on these fans.
What is EBL?
I think MaxExpress said he has his wired into blower high switch or maybe it was max AC switch.
Good to know there are options. Would be nice to have fan come on when coolant Temps come up regardless of AC compressor on or not.

Vehicles with aux fan had external from main fuse box relay that had a trigger from ecu. But don't remember which fuse fed it.

BowhunterBrown said:

But isn't 15 amp undersized? Pretty large gauge wire on these fans.
What is EBL?

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Nope, the fan isn't that powerful, it's a small pusher fan not a main radiator cooling one. Those wires are pretty small in the scheme of things. Keep in mind, GM undersized their wires to save money. That's why I'm running the A/C Clutch straight off the battery getting 14+ Volts instead of 11.4 measured at the clutch.

EBL Flash-II is an upgraded ECM with bigger tables and other features including "Learn VE" where you can drive around and tune your AFR automatically, especially with a WBO2 sensor hooked to it.

yevgenievich said:

Vehicles with aux fan had external from main fuse box relay that had a trigger from ecu. But don't remember which fuse fed it.

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My 1999 Tahoe had the fan relay in the underhood fuse box.

BowhunterBrown said:

Sounds like a good setup. But isn't 15 amp undersized? Pretty large gauge wire on these fans.
What is EBL?
I think MaxExpress said he has his wired into blower high switch or maybe it was max AC switch.
Good to know there are options. Would be nice to have fan come on when coolant Temps come up regardless of AC compressor on or not.

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For years I have wired my relay to the orange high blower relay trigger wire. If it is hot enough to need the added push fan for engine cooling it is hot enough that your blower fan will be on high speed. When you are rolling 50+ mile an hour, blower speed will likely be reduced from the added ac cooling and the fan turns off.

With the P59 swap I am moving the fan to PCM control.

BowhunterBrown said:

I am going to try the new Tahoe condensor as well. I ended up ordering after L31MaxExpress posted that up. Ordered the fittings off Amazon. We will see. I am going br9ke on this project, but I can't imagine what a shop would charge to rebuild entire front and rear hvacs on a suburban. And hopefully others can benefit from this effort.

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You would not want to know. I know what the local GM dealership quoted my parents on the 97 Express in 2004 to rebuild the a/c after the first compressor failed. I rebuilt the system for about $350 and GMs quote was over $2,000 at that time. Compressor, condenser, orifice tube, rear expansion valve, accumulator, a system flush and labor came to over $2,000 and that was in 2004. They also quoted nearly $5,200 for the engine replacement. I bought a new L31HD 4 bolt main for $1750 back then. They quoted nearly 30 hours labor and I did the swap in a weekend in Texas summer heat in my parents driveway.

Everything accounted for it was about $3000 to put a new engine, new water pump, new fan clutch, new belt, new hoses, new radiator, new compressor, new condenser, upgrade spider and other odds and ends. Ran like new after I was done.

L31MaxExpress said:

My 1999 Tahoe had the fan relay in the underhood fuse box.

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By 97 it was still external.