NY_Dutch
Well-known member
Something to keep in mind if you own an older F53 chassis coach like our 2001. Yesterday was a travel day for us, but just a short 2 hour run from one state park to another. We pulled out of Alafia River SP about 10 am, and about 25 minutes later i noticed the transmission temperature was climbing noticeably higher than normal, getting close to 200 degrees at the test port sensor, so I pulled into a shopping center to assess the situation. No signs of any leaks, the fluid level was ok, and did not smell burned, but I did find that the external cooler was not much warmer than ambient. Crawling underneath, I found the cooler lines were also not very warm, but the fluid bypass line that Ford used from 1999 to 2003 on the F53 4R100 transmissions was too hot to touch. The bypass has a spring loaded check valve setup that has a history of sticking open, so I tried rapping on the valve housing with a pair of pliers. After restarting the engine, within 10 minutes the temperature was dropping and the cooler was quite warm now as it should be. Since Ford discontinued the bypass after 2003, I decided to make sure the problem didn't reoccur by crimping the steel bypass line flat to seal it off. Doing some research last night, I found several sources for bypass elimination kits made specifically for the Ford 4R100 transmission of the same vintage as mine. I'll install one of them when I have an opportunity, but in the mean time, the crimp is doing the job and the temp stayed in the expected 130-150 degree range the rest of the trip. From my research, it appears the E40D transmission used on the older 460 powered F53's are prone to the same bypass problem.
After the transmission problem was sorted out we started out again, and soon noticed that the dash A/C was not putting out any cold air on an 85 degree day. Not wanting to delay our travel any further, I fired up the generator and we ran the roof A/C for the rest of the trip. Today I checked the fuses and compressor relay and found them ok, but the compressor was not kicking on. My gauge set showed the coolant pressure was high enough to trip the pressure switch, but I tried jumping it anyway with no luck. Next I tried jumping the wires to the evaporator anti-icing thermostat. Bingo! The compressor kicked in and we had dash air again. I'll leave the jumper in place for now, and replace the thermostat when I can. We'll just pay attention to when the cooling starts to drop off from likely freeze up, and shut it off for a few minutes to let it melt as needed. At least it's an easy fix that doesn't require my 76 year body to crawl under anything. Tomorrow we're on the road again for what I hope will be a very boring trip!
After the transmission problem was sorted out we started out again, and soon noticed that the dash A/C was not putting out any cold air on an 85 degree day. Not wanting to delay our travel any further, I fired up the generator and we ran the roof A/C for the rest of the trip. Today I checked the fuses and compressor relay and found them ok, but the compressor was not kicking on. My gauge set showed the coolant pressure was high enough to trip the pressure switch, but I tried jumping it anyway with no luck. Next I tried jumping the wires to the evaporator anti-icing thermostat. Bingo! The compressor kicked in and we had dash air again. I'll leave the jumper in place for now, and replace the thermostat when I can. We'll just pay attention to when the cooling starts to drop off from likely freeze up, and shut it off for a few minutes to let it melt as needed. At least it's an easy fix that doesn't require my 76 year body to crawl under anything. Tomorrow we're on the road again for what I hope will be a very boring trip!
