usrjcro11

Update on problems. Put a new clutch on fan. Helped little but high side too high. With truck running and AC on used a water hose on the condenser and pressure dropped immediately. Used truck pulling Lowboy and dozer. AC cool. Put gauges on it about two days later and high side high again. Replaced condenser and AC has been cool since. Thanks for all replies

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The parts guy at Mack said 2 cans or I may have misunderstood . I thought it was 3 cans also. What does everybody agree with. I know br said 3 cans. 

Thanks for reply. When I was flushing I thought I was getting good airflow. Going to take lines off and probably replace the condenser and might replace evaporator also..

It has a fluid control fan. I can here it and feel the air volume changing when idling.. The drier can only go one way because of the law pressure switch sticks out on the side. I will go check out anyway. Good point. Thanks

I replaced the fan clutch Wednesday. The clutch came from Mack. I only have less than two 12 ounce cans f freon in it with high pressure over 300 and low pressure around 25.  The expansion valve, drier, and compressor new from Mack. Mack said t only holds 2 cans for day cab and 2.5 cans on sleepers. Did I get wrong info maybe? I usually charge by high pressure 2 times ambient temperature .

Where is the high pressure switch located? I know low pressure is on the dryer.

tommrrow I am going to put a garden hose on the condenser while running and see if that changes high pressure. If it does not lower it does that mean the condenser is plugged?

thanks for all replies.

The truck started spewing freon out f the dryer bypass valve. After about 5 years from doing an AC overhaul.Thought it was stopped up ev. Since I was going to replace ex and dryer decided to replace AC compressor also. I also replaced the low side line from the ev to the compressor. I flushed everything while I had everything disconnected . Pulled vacuum and let it set overnight no leaks. Put one can of freon in and low side went to about 18 and high side to 150. Temperature outside was about 85 degrees . Put another can in and low side went to about 25 and high side went to 300. Did not it anymore in. Was thinking about putting a new condenser on it. The AC evaporator is cool but not cold. With the high so high am I wrong thinking the condenser has some partial restrictions? I took the side panel off the evaporator and blew it out. It was pretty clean. Any deals?  Thanks ahead f time.

My steering is leaking very badly on the bottom. I use this truck on the farm. I am going to replace the steering box with a remanufactured one. I have replaced boxes on regular cars and trucks but not a MACK. Anything specific I should watch for and what would be the proper procedure. On cars I would set the tires straight and install new gear box and count revolutions from side to side and then split revolutions and be at center. Is there stap ring holding on steering arm?  Thanks ahead of time for any suggestions. Also should I put in new bolts and are their any torque specs?