Home made APU

[jorden486]

https://amzn.to/2PMYWiG
Here is the A/C unit I used. It fits nicely in the closets on our Pete's. It needs an outside vent and comes with a hose so we just cut a small hole in the floor and sealed it up with an aquarium filter. I don't think it will handle Yuma at noon in August but my guys regularly stay in Yuma Calexico Phoenix etc in the summer and at night it did just fine. One guy would even let his run while he was loading so when he got done his truck was nice and cool for him.

The AUX tank is 6 gallons so I'm good on the amount of gas I'm carrying but I'd better come up with a better strap system for the tank.

We had 2 APU's carriers I think, that were on 2 trucks we bought used. We had nothing but trouble with them and they were harder on fuel than the generator is on gas. But that was years ago so as with everything I'm sure the newer ones are much nicer.

[barf]

I put an APU on this truck when I bought it new, 9 years ago. The APU has over 12,000 hours on it. It died on me just before Christmas, just after I spent $450 on some service and an oil change on it. I found a generator on a boxing day special for $400. It may be an economical way to go, but what a pain in the ass! I miss my APU.

-when you can't pull up to gas pumps, carrying a gas can across a truck stop parking lot.
-just the pain of handling gas, time involved pumping/pouring/extra tax paperwork
-I have to get out of the truck to start/stop it.
-requires much more frequent oil change (bonus though: no filters, much cheaper)
-I run where it's sometimes too cold for just an electric heater, and I'm worried about the truck starting in the morning, so I have to idle the truck on those nights.
-cold engine starts on cold mornings where I didn't idle all night (APU keeps engine warm)
-and now after reading this thread, I have to worry if DOT will ticket me for it

That's all I can think of right now. Money's tight but I'm going to end up fixing my APU.

[jorden486]

It may not be the ideal situation for everyone but works great for us. I have only had 1 trip where a driver had to buy gas on the road. If you are out for extended periods it could become a problem. My trucks carry another 2.5 gallon tank in their step just in case they have a long trip.

[Rawze]

(03-12-2017 )barf Wrote:  I put an APU on this truck when I bought it new, 9 years ago. The APU has over 12,000 hours on it. It died on me just before Christmas, just after I spent $450 on some service and an oil change on it. I found a generator on a boxing day special for $400. It may be an economical way to go, but what a pain in the ass! I miss my APU.

-when you can't pull up to gas pumps, carrying a gas can across a truck stop parking lot.
-just the pain of handling gas, time involved pumping/pouring/extra tax paperwork
-I have to get out of the truck to start/stop it.
-requires much more frequent oil change (bonus though: no filters, much cheaper)
-I run where it's sometimes too cold for just an electric heater, and I'm worried about the truck starting in the morning, so I have to idle the truck on those nights.
-cold engine starts on cold mornings where I didn't idle all night (APU keeps engine warm)
-and now after reading this thread, I have to worry if DOT will ticket me for it

That's all I can think of right now. Money's tight but I'm going to end up fixing my APU.

We always hated walking across a parking lot with a gas can. Especially when shut down a couple days due to a blizzard, it freezing cold outside.

We also got flack from other truckers about the fumes. it is no different from running an APU as far as fumes go, but it is a different smell, and other trucks sitting next to us would complain sometimes just because it was a different smell that they are not used to. I don't blame them one bit, so we always kept running it to a minimum.

========

We now have the APU and have had it for many hundreds of thousands of miles. I have in-framed my truck engine and the results of not idling at all are on youtube for all to see. We paid $8,000 installed (it was a re-man unit), and have spent our share of money replacing compressors and belts and fixing leaky hoses, etc. on it over the years.

Here is my thoughts on it...

A factory stock CM871 will typically use about 40 mg./stroke fuel at idle. A truck with MM in it only using about 12-15 mg/stroke at idle.

Ruynning the RPM up at 750 produces enough oil pressure to keep everything lubed well, and adding a gallon of gear lube helps reduce wear too.

So...

A factory stock truck with only 15-40 oil pulling 40 mg/stroke all the time, sucking soot nonstop and wearing the engine out -- APU is much better to have. You are killing your engine and the overhead cams by idling one this way all the damn time.

If your one of those who runs an EGR soot-sucking engine that is hell bent on destroying itself, and using regular oil, cams getting plugged up and soot packed, etc. factory 40 mg/stroke -- An APU and a bypass oil system is its only savior long term. For this situation, the cost is a good investment.

==
A MM truck sipping minimal fuel, shimmed oil pump, a gallon of gear lube, -- YOu would not be able to justify the cost of an APU at all. Hell just the maintenance costs on the APU over the years is more than the wear and diff in fuel costs. I cannot justify the cost of an APU at all when the truck is set up this way. It is flat-out an expense, and if it is engine longevity you are concerned with,.. well my own engine after the same 950k miles, even if the wear was 40% more, would still not justify it. -- I simply don't see it as a benefit at all to have an APU if someone has MM, has a shimmed pump, and is using gear lube in the engine. Not even for the reason of extending engine life.

I DO HOWEVER think that if you have one, it is a luxury that becomes hard to live without. The electrical power is nice to have and the A/c is nice too, but those things can be done on the main engine with a bigger alternator and keeping the truck A/C in good shape. - Looking back at it all, I would not have purchased the APU, but would have idled the truck a lot more instead. I would however have a small generator for those times when i only wanted to power up my laptop, etc. while sitting, or perhaps would have added extra batteries to the truck for that reason, but NOT an APU.

That is just my own thoughts on it.

[farmboy]

(03-12-2017 )snailexpress Wrote:  I don't have exact numbers handy now it is in regulation. Some guys have it pay. Or make enclosure

how do you like that generator? My neighbor is a dealer for them and is really pushing for me to try one.

[snailexpress]

(03-12-2017 )farmboy Wrote:  

(03-12-2017 )snailexpress Wrote:  I don't have exact numbers handy now it is in regulation. Some guys have it pay. Or make enclosure

how do you like that generator? My neighbor is a dealer for them and is really pushing for me to try one.

This is not my truck . Took picture when was broke down in Houston. Canadian driver parked next to me.

[snailexpress]

Here is my home brew setup.
Split system AC.
Powerful and quiet.
No weigh moving forth and back every stop.
No openings cutting.
All space inside sleeper still available.
Generator has fuel from truck fuel tank, remote start.      

[Nilao]

If I went with a generator setup I'd go diesel and plumb the fuel line to the main tank. I have acquired a tripac from a friend of mine for $2000. He decided he wanted a new one due to the nickel and dime stuff irritated him. It has a new alternator and a/c compressor.

[Waterloo]

Cool, thanks Jordan! That is a sweet little unit, and would fit in my wardrobe closet, "I think", in my ProStar and vent out of the floor. Still have to measure... And at 925 watts, looks like my 1800 watt inverter would handle it.

I have a Tri-Pac that works great when the temps are below 90*... But, I will file this just in case, and that split unit install above, that was pretty slick. Thanks for the info!