1991 F150 5.8L w/ R134a refrigerant.

The system has had a leak in it since I've owned the truck. I tried charging it last year and it did pump out some good, cold air for about 2 hours, but didn't maintain. (I didn't know at the time that it leaked.) I do not know exactly where it's leaking from, but when I inspected for leaks last year, it wasn't coming from any lines/connections that were exposed in the engine bay. I suspect the drier (I think- whichever part is encased in black plastic @ the passenger rear side of the engine bay) is what's leaking.

I decided to delete the A/C system this year, but I have since decided that I would at least try to seal the leak before doing so. I am not going to buy any new components, so if the leak sealer doesn't do the job, the A/C is gone.

I was wondering what recommendations/experiences y'all have had with using A/C leak sealers. I'd like to keep it under $30 if possible, but may go higher than that if it's worth it.

As always, thanks!

 

Don't bother. It will cause more problems and possibly cause component failure. If you can't afford to fix it right, might as well leave it alone.

 

They may work for a short time but it will leak again. If you want to find the leak buy the refrigerant with the UV leak detector in it, then when it leaks out you can find the leak. Odds are that one of the O-rings has dried out, and is leaking. next best option for a leak on an older truck is the actual rubber hoses are deteriorated from 20 years of service and are leaking. If it is leaking at one of the O-rings you can buy vehicle specific O-ring kits. after finding and fixing he leak evacuate and charge.

But like I said as far as leak sealers, temporary fix at best, as quick as you said your system leaked out last year I really doubt it will do anything

matt

 

Just a thought, stop leak in an a/c system is just a crutch and can wreck your compressor. Did you replace the o-rings (use green ones). Why do you suspect the accum dryer? Is it oily around it? If so, a likely candidate.

 

I haven't replaced anything on it, o-rings or otherwise.

I suspect whatever part is located inside the plastic casing @ the rear of the engine bay as leaking b/c when I inspected for leaks last year, there weren't any obvious leaks coming from the exposed parts of the system. So, the only conclusion I can come to is that the only part of the A/C system I can't see is the part that's leaking.

Either way, it's a moot point. If the leak sealer is just a crutch/temporary fix, then it's not really a fix at all, so I'll move ahead with deleting the A/C system.

 

Why delete it? For resale an intact non-op ac system is better than a partial system.

 

1) To clean up the engine bay and finally remove that super irritating A/C line that runs right in front of the oil filler neck.

2) Who said anything about resale?

 

"part is located inside the plastic casing @ the rear of the engine bay "
is the evaporator core.
the only way to properly find a leak is with a sniffer, or UV dye and a black light.
it may just have a bad o-ring in one of the connections.
or you could have a bad seal in the compressor, or a bad evaporator, or condenser.
you will normally not see a leak, you have to find it with a tool most of the time.