That's probably a good idea since you don't know the history of the old compressor and if it has any internal damage/contamination.So now im wondering if i get all the ac parts listed for my truck except the ht6 compressor and get a sanden compressor instead will that work?
What pump are you able to achieve 30" of vacuum? 28.9" is a perfect vacuum and not necessary for an A/C system. Your gauges must be inaccurate, sorry. Just sayingGet plenty of vacuum oil for the pump (I get it on Amazon, 32oz bottle; it's more expensive at the stores). I've almost always had to change the oil in the vacuum pump at least once every time I use one (it takes maybe 8oz) to get it to draw to 30" of vacuum. When the oil is contaminated, the pump won't pull full vacuum. Get oil.
What pump are you able to achieve 30" of vacuum? 28.9" is a perfect vacuum and not necessary for an A/C system. Your gauges must be inaccurate, sorry. Just saying
In a smaller system you should put about 4oz in the pump and 4oz in the receiver/dryer for a total of 8oz. If you put it all in the pump, you'll slug it and possibly hurt it.Somebody should mention that he should put some oil in the receiver-dryer so the new compressor sees oil on the inlet promptly.
I completely agree with your entire commentYou're lucky if you can get it below 28" with these cheaper pumps from places like HF. When I evacuate a system, I leave it at a vacuum overnight, if I have the time. Otherwise I'll suck it down until it won't go any further, shut off the pump and make sure it'll hold a vacuum for at least 1/2 hour or more.