Automotive Air Conditioning Information Forum

In my experience the SD7H15 needs a smaller orifice tube in a GM system to even perform adequately. I have a Sanden 4261 on the 350 Vortec in my 1987 G20 van. I fitted it with the largest parallel flow condenser that would fit the core support opening, crimped my own hoses, and used a Ford Red ...

Having 3 GM vans myself they all have vacuum actuators even a brand new 2025. There is a vaccum storage ball under the hood. There is a check valve between the engine vacuum source and the vaccum storage ball. Either the check valve has failed our you have a vacuum leak in the system. On my 97 ...

This is a long thread and getting hard to follow.
Has reheating been eliminated? Those pressures are too high. Clamp off the heater hose.
Are there under hood components too close to exhaust components, if so insulate them. Is the low side line insulated?


Dual evaporator system is going to run ...

On a side note, no oil would drain from the old compressor, as in not a single drop even turning the pulley. However, I drained about 8 oz out of the old receiver/dryer. Total system spec including compressor is 11oz.
Eight ounces of oil came out of the old R/D and none from the compressor? Oh ...

Sounds like you made good headway. Fan install also looks good. Almost like they should have been there from the factory. I have both of my fans on the bottom rows of the condenser vs your offset mounting. Probably tomato vs tomatoe but I made the assumption the condenser was hottest at the top and ...

Orifice tube should be in the evaporator inlet. I have had probably a dozen of the Express/Savanna systems apart and same difficult as heck place to get at location for all of them. I say difficult because they love to stick and it is hard to get a puller on the tube where the line sits in regard to ...

I just dug into the Ford catalog. Looks like the OE rear expansion valve is an H block. Ignore what I said about the capilary as it does not apply. That being said if it is not an OE expansion valve, get one and try it first before you spend days chasing this ac cooling ghost. The pressures ...

Microtube parallel flow is going to cool the best for a given condenser dimension. A subcooling model would work even better but it is hard enough to find a proper dimension microtube parallel flow for older vehicles as it is.

Your pressures sound like what my Express van did when the flat out ...

Lot of assumptions there Chris.

My intake picks up air from the same place the condenser gets it - in front of the core support. The mainly plastic intake tract heat soaks a small amount.

Idling in traffic surrounded by other vehicles blowing out 150+f air from their heat exchanger stacks raises ...

One other thing I swear by. ICE32 additive and I have been using it for 20 years now in everything I touch. I personally watched 2oz of the stuff injected into my at the time basically new 2002 Ram with an oil injector while the system was in operation drop the head pressure nearly 25 psi within 5 ...