is lead additive necessary?

The old Farmall 300 that my dad bought new in 1955 is still going and probably has well over 25,000 hours on it. It is now on it's 6th set of pistons and sleeves. I know it was doing 4,000 hours on a set. It probably hasn't had a drink of leaded gas since 1970. Most of these tractors have had a valve change by now when being rebuilt. It wasn't valves that caused rebuilds in any of my tractors. Blowby will take these old gas Farmalls down long before any part of the head gives trouble.

This reminds me of the hype about "Ya can't put R-134A in a R-12 cooling system".

All hype to get the old stores used up, and boy did we fall for that tale for quite a number of years. :>)

Allan

If you get as much mineral as possible out of the compressor, flush the system, replace the dryer, and add the correct amount of polyol ester oil before evacuating the system and recharging with R-134A, it will work great!

Yep, that's what I do too, except I never did buy into the "replace the receiver" theory either, unless there was evidence of metal floating around in there.

I just give 'em a good healthy flushing, swap the ports and fill 'em up.

They aren't quite as efficient as the old R-12 was, but do work well for years on end.

Thanks for the hollar,

Allan

I, as per usual, didn't make myself clear. :>)

I agree you can't "mix" the two. But, the real question comes in on the cost of that "retro-fit kit".

All the change over requires is a darned good flushing, change the ports and add a few ounces of R134A oil, which aside from the freon, should come to no more than $30 or so.

Now, in the case of CNKS, who had a blown compressor, I'd replace that dryer also because it is almost impossible to get all that scrap iron out of the thing.

Have a good one,

Allan

I have dealt with that on two systems this summer, where others did not get enough of the old oil out, and it ain't pretty!