7040 A/C question

I have installed the sanden compressor and had to remove the old manifold from the A6 compressor. The new R-134 fittings screw onto the fittings on the manifold. The question I have is the manifold has valves that will shut off the ports for the fittings and or the ports for the hoses. I assume that pulling a vacuum I will need the valves set in the middle to draw vacuum from the hoses and the compressor? Also I am under the impression this set up was used to allow a compressor change without removing the freon? So after vacuum and recharge I need to open the valves up to allow full flow for the hoses and shut off the ports for the fittings? Sorry for the questions my experience with R-12 systems is limited and I don’t recall seeing this arrangement in the past.

Have you tried to locate a new manifold? I have googled A6 compressor manifolds but can’t find one like I have. Usually if you only have to add a pound of Freon once a year I don’t consider that too bad of a leak but after paying $349 for a 30lb tank of R-134 last week I am rethinking my acceptance of Freon leaks. I bought a kit that replaced the compressor, all the hoses, the expansion valve and I went ahead and replaced the condenser. I haven’t pulled a vacuum yet but I hope the evaporator is ok.

I have two others. One on a 7060 and the other a 7045. The ports are oriented in a different position so elected not to use them. Maybe not critical but if I convert them, will need for those applications.

Got to run the tractor today and wasn’t impressed with the a/c. It seemed kinda cold coming out of the vents but didn’t cool the cab like I thought it would. It was 80 here today and I was cutting hay. I thought I checked the drains up top but evidently I didn’t because every turn I got a nice shower falling out of the filter housing. I don’t know if I have too much Freon or not enough. I charged it at 1.60kg which is the upper end of what was recommended by the company I bought the a/c parts from.

I had replaced the cab and when I removed it I cut the heater hoses and coupled them together. I was going to replace the heater hoses but I needed to get the tractor out of the shop and cut hay. So the heater core has nothing going through it.

Joe(TX) wrote: The calves do not allow the change of the compressor. They allow everything else to be changed.

Really wasn’t sure what to expect, I would love hanging meat cold but the only cab I can compare to is a friends Kubota and it wasn’t really all that cool. Cool enough not to open the door and windows but maybe 8 degree difference between inside cab and outside. It was 80 yesterday with typical NC humidity so it’s a lot for the a/c to overcome?

Ok I will try that, when I took the roof cover off to paint it I wondered why there was a feed sack up there.

Another thing I've noticed is it seems that these are unable to recirculate cabin air only. IIRC the 200 cab has a door you can close to stop outside air from
Being drawn in where as these 7XXX cabs do not have that feature? I think it would if were able to not blend outside air

A little follow up today. Had a 89 degree ambient temperature and hooked the 7040 to the baler to finish first cut. Checked pressures on the compressor.
Low side seemed a little low as compared to the chart but didn't have more on hand to add. Took along a thermometer and it showed cab temperature at 75. Perhaps a little warm for some but I was comfortable and stayed out of the dust

Measurement taken with fan on high and engine speed at 1000 RPM

tbran... is the pressure on this tractor different than what is expected on a truck ?  With R134 in the system, i normally like to see about 35 psi on the low side and 240 or so on the high side... Temp out of the vent should be maybe 45 - 55  degrees .............. all on a 90 degree day.

Edited by steve(ill) - 29 Jun 2022 at 10:30pm