Venturer

1 hour ago, Ivylog said:

I’ve been using the UF for 40K miles on my ISX 525 and it turns on the check engine light in a couple of minutes. No exhaust gas temperature and on a long pull I’ll manually downshift to keep the rpms above 1700.  Other than that I don’t worry about it.

That's what I was hoping to hear. Although you have the ISX, my ISM should react the same. Logic tells me that allowing hot exhaust gases back into the intake would cause the engine to run hotter. Others say that with all fresh air the combustion is more complete generating more heat. I guess I'll keep running it the way I always have keeping the rpms near 1800 on the long uphill pulls and not worry about it. My previous 450 ISL would run up to 210 degrees on the long uphill and then cool down to 190 before climbing back to 210 where the fan would kick into high. This ISM gradually moves between 185 and 199 depending on load. Have never seen 200. 

After re-reading most of the previous UF posts, questions remain. Some claim that with the EGR valve closed below 7,000', the EGT can rise to a danger temp on a long pull at near maximum power. Others say that without the hot exhaust gas blending in with the intake fresh air, the engine will run cooler. Some have run the UF for several thousand miles with no ill effects. Yet some have issues with it and have removed it. I've been running one for 3,000 miles with no "known" bad effects. I've let the transmission choose the gear 90% of the time. This summer, we will be in the mountains to about 8500' and next fall up to 11,000'. Out of caution, I am tempted to install a pyrometer to monitor the EGT, but that's no easy task. So, my question is directed to the ISM owners who have experience with the UF and any adverse effects. What have you done to ensure the engine integrity? Has anyone measured EGT before and after the UF? Thanks for your comments.     

7 hours ago, CAT Stephen said:

Doug,

 

What is key is that your system is yielding a 33 degree temperature drop which is good and means that your compressor is currently sufficient.  Using static pressure to troubleshoot or to reveal leaks is inconclusive.  Inject the UV dye that I specified above into your system and follow the procedure to reveal leaks.

That sounds like my next step. Need to gather some items and find the time to search further. Thanks for the help. 

After checking the static pressures for four days, the values seem to be 4-5 psi below the ambient temperature. A 52-degree morning saw 50 psi static. Later in the day 67degrees saw 62 psi. I think this means I do not have a serious leak when not running. The temp should get to 80 on Saturday. I'll start it up then and see how much temperature drop I get. In the back of my mind, I'm suspecting my new compressor might be the culprit. It couldn't build to the expected pressure after I had close to 60 oz in the system even though it was bringing the temp down 33 degrees.  

34 minutes ago, Dr4Film said:

My experience with the Blue-Ox Tru-Center was way less than pleasing due to the money (thousands of $) and time I had to throw at it to keep it working. I finally had Josam's remove it, then bench fixed it so it was working once again and sold it to another member for $200.

The initial cost was about $800 then another $200 for installation. It worked for a couple of years then stopped working.  I had to pay a shop to get it working again. Then less than one year it stopped working again. Our travels took us close to the home shop in Nebraska so we stopped there to have it looked at. Well, another $600 later for a new piston and it was working once again. They also drilled holes in the solenoid box to alleviate any moisture build up which could cause the solenoid to freeze up. Then some time later it stopped working once again.

That's when I finally decided that I no longer needed or wanted it any longer. I had thrown way too much money and time into trying to keep it working. It was more of a boat anchor than a useful tool.

I decided that if at sometime in the future where I wanted another type of steering system, the only one i would invest in would be the Safe-T-Plus with the Henderson SuperSteer Trimming unit.

 

I think I would have done the same as you if mine had worked the same. My first one was on our 03 Tiffin and it worked flawlessly for several years till a bracket broke. After the brake, one end dropped to the road and ruined it. This current one cost me $129 shipping. I installed the electrical and paid a shop $50 to install the cylinder. Less than $200 invested. So far, it's working as designed. The coach was pretty stable before the installation. The TC just firmed up the directional control. Time will tell if this one will be like my first one. 🤞

It's no secret that the big truck stops can have higher pump prices than the smaller stations. However, in 4+ years I have been using the Open Roads/TSD card, I have never seen prices below what my final price was. My son stops at Maverick stations, and they are very often close to my discounted prices at the big TA's, Loves, and others. As already mentioned, the convenience of pulling in, fueling up, and parking for lunch without going inside is a bonus beyond the savings.

30 minutes ago, Chargerman said:

Thank you guys. I’m still not clear on a couple things. I get how to activate it but let’s say I set it off center because of a cross wind. Does the steering then always remain in this position until I center the wheel and push the button again? Am I right in thinking once you press the button once it always remains active? I’m thinking this is the case and that’s why folks say it helps maintain control of you were to have a blowout

 

It's only active and changing when you push the button. The two opposing springs will attempt to hold the steering in the set position. Yes, when conditions change, you have to reset the spring tensions/position with the button. To be clear, it's always there, however, you determine where it centers as you need with the button which is allowing the opposing springs to reposition to hold where you set it.  

Today, 30 hours later, I have 70 and 70 @ 72 degrees. I'm not going to start it for a few days to see is the leak is only at running pressure. Like Bob, I also have lower running pressures when I know the system had to be full.  

40 minutes ago, Chargerman said:

Ok . Thanks guys! I’m fine with just wiring direct but help me understand how it works. If you supply power to it momentarily I understand that it will actuate the solenoid thereby engaging the Trucanter but then what happens? How does it stay engaged? How is it released?

There is spring tension on both sides of the centering valve inside the tube. When you have to steer into a cross wind you are putting more pressure against one spring. While holding the steering wheel into the cross wind, pushing the button causes the springs to center to the steering position. After centering, you have the assist of a spring to hold the steering wheel position. Sometimes you might have to steer past the position you want, then push the button to create more spring pressure to hold the position. I've never had a time where I had to hold the button more than 3 seconds.  When conditions change, just repeat to the new position. All you're doing is resetting the spring pressures for the new road conditions. It will stay there till you change the centering. There is no power to it except when you change the centering with the button.

What Ivylog said. As long as the solenoid responds when 12 volts are applied, you have a working Tru-Center. All you did is transfer the engagement timer to your brain.   

6 hours after topping it off, both gauges have settled @78 psi with 82 degrees ambient. I'll check over the next few days without starting it to see what I have. It supposed to be cooler, so I expect the numbers to be slightly lower too.  

The OAT has reached 77 degrees, so I gave it another try. Standing pressures were 65 on both high and low. Once started, the high went to 125 and the low was at 15. I added most of another 12oz can for a total of 58-60 oz. The high came to 155, but the low is still around 15. I'm going to stop with it here. With the OAT @77, the vent temp is 43 for a 34-degree drop. That's good enough for me regardless of the pressures so I'm stopping here. I would think the pressures would be higher with a new compressor, but being new today doesn't guarantee it's working as designed.  I know what I 've done is only a temporary fix, as any leak is still there. If it doesn't leak when not in use, I'll check and add if necessary when we need the cooling. Until we get back to AZ in Oct, I can use the generator and roof air if necessary. Thanks to all who offered suggestions. I'm a little more informed now than I was a few days ago. Owning an older Monaco is like going to school again, except I have more teachers. 🙂 

What Richard said. Our Aqua-Hot is the same model as yours and had a similar failure. I called a Mobil certified tech who came to our house and watch him open it all up. Mine turned out to be a failed high limit switch. I also had him service the burner and replace the filter. It has worked flawlessly since. I might be able to do it myself the next time, but he was good and for $500 every two years, I'll let the professional do it.   

When I checked on it this morning, the pressures were equal at around 65 psi which to me, indicates no major leak. When engine started and AC engaged, the high settled near 75 but the low was below 10. The OAT was near 50 degrees. It's supposed to be 77 tomorrow and will check it then.  

I'm probably going to put my AC project on hold till the OAT gets up into the upper 70's which will be awhile. I have 48 oz into the system, however, over night the high and low pressures are lower than yesterday. I either have a substantial leak or the colder temp is affecting it. Warmer temps will help.  

I do not have a fan blowing on the condenser

I have been charging it on high idle @1000 rpm. Tomorrow, if needed, I will top it off @ 1200 rpm.

Thanks. I'll pick up another few cans tomorrow and top it off. We only have a few trips planned this summer before we go back to Havasu in Oct.  If any leak becomes bothersome, I'll just rely on the generator and roof Air and have the shop there locate the leak. 

Sorry Ivan, my cans were 12 oz and not 16, so 48 oz added. After 30-40 minutes, the low pressure is up to 40 and the high is down to 75. Am I correct is assuming they will equalize when the compressor is not running??  

After another attempt, I was able to get the high up to 145 psi which is in the range for 67 OAT, however the low wants to stay near 10. After I shut it off, the high drops to 100 and the low settles at 25. The vent temp is now 37 degrees which is 30 below the OAT. The cooling is fine, but I don't think the low pressure is where it should be while running @1000 rpm.  Am I wrong?? I'm going to let it sit overnight and see what I have tomorrow. So far, I have used four 12oz cans.

After sitting for a couple hours, the low was 30 and the high was 50. Virtually no change. I started charging again and was able to get some more 134 into it. Maybe a total of 18-20 oz. The OAT is 65 degrees and the AC vent is at 39 degrees for a 25-degree drop.  This all seems so odd when the compressor wouldn't even engage due to being so low to cooling 25 degrees with only 1 1/4 16 oz can of 134 added. Now, the standing pressures are 25 on the low and 75 on the high. When running, the high is at 110 and the low is near 10.       

3 minutes ago, trailmug said:

Sound like a huge leak, running high pressure should be triple digits. 

0 high 25 low doesn't make sense. Sorry if this is condescending, but make sure you are turn the service port adapters clockwise to depress the service valves when reading/filling. 😁

Both high and low hoses of my kit have 90 degree valves and both are open. Otherwise, I wouldn't get any reading. I'm puzzled as to why it won't take any more than 8 oz and the high side does not build pressure over 50. I would think the pressure would drop after shut down if there was a major leak.

Yes, the dryer was changed. I just tried adding R134a to the system. After I was able to get some into it, the compressor clutch engaged and I thought I was on my way. However, the high pressure would not come higher than 50 psi while the low showed 10 psi. I could only get it to take about 8-10 oz of coolant. After shutting the engine off, the low pressure settled at 35 but the high remained at 50. After sitting for 10 minutes, the pressures remain the same. Is this telling me my new compressor is bad??

I hooked up the gauges and found that without the engine running, there was zero pressure on the high side and 25 psi on the low pressure side. When engine running, the compressor will not engage which is telling me the freon is too low. To recap: Two months ago, I had a shop check the system. They did a Nitro fill, peg oil w/dye and found the compressor leaking. Replaced it with a new Sanden, did an AC flush, vacuumed and recharged the system. All seemed well. With that service having been done, can I just add R134a until the pressures reach their correct levels for the OAT? That's assuming the compressor will engage when there is enough refrigerant in the system to safely run. Years ago. I just added R12 till the bubbles disappeared in the site glass. I haven't looked for the site glass but have the gauges now.

Edit: I realize I need to find the leak and correct it. I'd prefer to have the shop in AZ do the work, as they know the system and their rate is half of what is charged here for RV service, however, we won't be back there till Oct.  

Thanks, Tom, for your comments. I have it under our RV port here in WI so it's out of any direct sunlight. It's supposed to be in the 70's on Sunday and will hookup the gauges then to see what I have. It should be an easy check and recharge as the fittings are right at the new compressor. Hopefully, I will just have to add some R134 to get it cooling again.   

7 minutes ago, jacwjames said:

I have a chart in my owners manual that shows pressure based on ambient temp. 

The gauge set has a chart with it. I didn't realize that different ambient temperatures resulted in different pressures.