Build Thread Mustang5L5's Build Thread -

Willybill32 said:

I bought enough R12 to refill the system on my '86. It held a vacuum for 24 hours, but once filled, the R12 leaked out!

Bill

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That's why i'm going to fill with Nitrogen first. The molecule size is slightly smaller than R12 so it should show a leak if any without wasting precious R12.

I also purchased a tube of Nylog, which is used in refrigeration/HVAC on O-rings/seals as a sealing promoter. Means i need to pop off all the connections and apply. PITA but now is the time to do it.



Nylog Red is for mineral oil/R12 systems. Nylog Blue is for R134a/POE oil

TIGGER said:

Thanks, I learned something new today. Curious how are you going to fill the system with nitrogen?

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Perks of my job i guess. I work with gases at work so i have access to tanks, regulators and bulk nitrogen. I have a small tank like this filled with 500PSI of nitrogen. Just gonna hook the regulator up to the yellow line on the AC manifold guages and fill it up to about 100psi.


Since it's Jan, i can just let it sit for a couple weeks and see if it leaked out. I can also add a little leak dye and fill it again if needed to chase down any leaks. Hopefully not. I don't technically need AC in MA until late June, so i have time to really play with this before I charge.

I'll post pics when i do this. Trying to find some time to set up my vacuum pump and let it draw down for a couple hours.

This post is for my own info so i can search it later on if needed: Belt length, pullies

Needed a new belt for my 93 cobra pullies. Setup is the LMR 93 cobra pullies (all three), stock PS pulley, stock AC compressor pulley. Stock accessory pulley setup with the smog pump deleted.

Two belts fit this setup.

Gates K060820 (82 1/2" long belt) - Fit on the tight end of the tensioner range
Gates K060825 (83 1/8" long belt) - Fit on the loose end of the tension range.


Since i anticipate some belt stretch, i went with the K060820 belt.

Work up to -1 degree temps this AM. Too cold to go to the garage and turn the heat on and wait.

Decided to test my $50 “electronics yard sale” punp. Bought this 10 years ago specifically for this job. Been sitting on it since. It is a lab grade pump, but just old and dirty. I changed the oil and decided to finally test it. I knew it would work though.

Target is to be able to pull the system down below 500 microns.

Hooked up a fancy Bluetooth micron Guage.



5 microns. That’s pretty damn good.

90sickfox said:

$50 pump with $400 gauge for the win.

I looked it up.... I'm going to have to save up a fee more pennies. I really like the graphing capability. How many people can say they have a Bluetooth vacuum gauge ?

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It’s got some really nice features plus the ability to set it up, walk away and check on it remotely. (Like while in a cold garage)

It will also graph decay/leak-down.

So, pulled my initial vacuum. I didn’t feel like turning on the garage heaters for an hour to work in there (it’s 0-5 degrees here in the northeast garage is a chillly 40 degrees), so I did a quick and dirty vacuum pull just to start the process of removing moisture.

Nothing fancy for this initial pull. Hooked up manifold guages and vacuum pump and let it run 10 min. Guage set showed -30 inHG so I disconnected and let it sit.

Went back in and checked on it and looks like it’s holding. Good news so far.

I’ll need to release the vacuum when I break down the connections to apply the Nylog. I just wanted it to sit for now under some sort of vacuum to start removing moisture from the system.

When I do it “for real” I’ll be hooking up my micron guage and pulling a deep vaccum and doing a leak-down test.

I’ll document that in a bit more detail.

After this, time to start modifying my Strut tower brace to clear the Hydroboost MC

Some more experimentation today. I’m waiting on some stuff to arrive before I do this for real, so I figure I play with the equipment a bit.

Normally you don’t hook the guage up here and you hook up both the high and low side to pull vac. Waiting on the tool I need to hook the guage up directly to the LP side and take good readings of the system.



But wanted to see what this guage could do, so I let it rip. Now, my manifold guages went right to -30 pretty quick, but it actually took 10-15 mins to make it down to 1000 microns. The target is 500.

The hoses don’t help. They all leak which is why you put the guage near the system and not at the end of 20 feet of line.

Stopped my testing around 1000. This was just a test.



Decided to just try the leak down test. This shows if you have moisture in the system still boiling off. Saturation temp in the lower right is the temp that Moisture will boil off in the vacuum that the guage is measuring. Cool features