Ideas for my "On-Board" Air?

This is were I installed my air compressor. Been in that spot for two years, use it a couple times a month in the Pine barrens or on beach runs. I made a four tire hose setup to inflate them all together.

 

Ok, im defensive now. Also, a compressor, didn't charge my co2. Its liquid. I wonder if you understand what is in there, and even going on here. (talk about being defensive). But thanks mate. Also, if some compressor down the line, did get my liquid co2 into a tank, and then into mine, I didnt pay for it. Cheers.

 

Thats fair. I mean, how much "gas" ,,, errrrr air do you need? Ive ran my tanks for a very very VERY long time, not just for tire inflation, but tools. And have never ran out on a trip. Toss another one in, or, fill it (like your gas tank) when your back, (for 4 dollars) and im back into it. Again, do you mate. Ill do me. Cheers and happy adventures

 

Ya,.. dont help with a liquid.

 

No worries. I didnt mean to come off as "defensive" or how ever everyone else read that. Ive had onboard air, and, well, prefer my tanks. I hope you find what you like, and it goes well. Happy adventures out there all.

 

What is all the rush airing up? That time is what beer and trail-talk with buddies is for, at least for me.

 

Cool, than you can use a manual pump if you like. EDIT- then why does this entire thread even matter.

Again, its all up to you. Cheers.

 

I use 24v drill motor battery type pump that has presets, takes about 20-30min/two beers to do all four.
I transfer it between a couple 4Rs, my truck, motorcycle and a SxS. Very handy

 

Cool. Do you. (odd you brought up time) Happy adventures out there mate

EDIT- can you run air tools and such off that? I may have to look into that. I mean, i wont, but, Again, do you.

 

Why?

 

Ah,. 10-4. Good stuff.

 

Plenty of tools run off batteries now.

 

I have a Costco plug in pump. Guess what my wifes job is after we hit the trails

 

Got the same one, doesn't take up much room.

 

I wrote this article about a DIY installation of a VIAIR 400H-A, underhood near the firewall on the passenger side.

https://trail4runner.com/2021/11/16/viair-400h-on-board-air-install-5th-gen-4runner/

I purposely mounted it with the switch toward the fender, with the intention of keeping the cool side cool and the hot side hot (queue the old McDonald's commercial for the McDLT ). It works well, and a couple years underhood seems to have had no effect on it.

I modified it slightly, to make for an easier connection at the air hose quick connect. I put a "thread protector" (local hardware store) over the nipple to keep the dirt out when I'm not using it.

 

Maybe I’m not envisioning this correctly, but it seems the hot side (with the cooling fins) is closer to the engine. Is that what you intended?

 

Interesting. Maybe I'll follow suit and use that orientation. Thanks.

btw, you happen to have pics on this site of your Oval window?

 

this is exactly the sort of thing that I was interested in... I'll be looking closely at that article!

 

I got a Milwaukie m18 air pump. Pumped up 3 cars from 22 psi and had almost full battery. Pretty fast too.

Also have a small motorcycle air pump as a backup.

 

I think what he’s thinking is to put the part of the compressor that is designed to handle heat the best closer to the heat.

 

Exactly

 

My '57 was a long time drag car project that I lost interest in before selling it not long ago, after owning it for ~30 years.

I've since built a '58 that I have fun with on the street and strip. Here are pics of both.

Are you a VW guy too?

 

Do you have a photo of the engine bay, further back, to see how that looks overall?

 

That compressor part, the finned metal body, is a radiator of sorts. Like an air-cooled motorcycle engine. So by locating it nearer to a heat source you could be lessening its ability to shed the heat it generates when operating. But that probably doesn’t matter as much as the fact that you’re starting out with a pre-heated compressor.

When I use mine, free standing, to air up from 22 to 32 PSI it takes a longer time to get that 4th tire up to pressure than the first. And the metal radiator body gets very hot. Starting out with a hot compressor would only make it worse. And perhaps shorten its life.
Maybe this isn’t an issue with larger compressors. It’s best to check the operating specs.

 

My reasoning was that the cylinder side of the compressor is more likely to withstand some heat from the engine than the side that the switch is on.

The compressor doesn't get that hot in it's current location when it's not being used, and it still works the same as it did on day one, after over ~2.5 years. All good.

Regarding your experience with the inflation time of your 4th tire, that probably has to do with the duty cycle of your compressor. I saw the same with the

$77 VIAIR 88P - 00088 Tire Inflator Portable Onroad/Offroad Air Compressor for Car, Truck, SUV & RV | 12V On/Off Road Tire Pump Air Compressor Portable Heavy Duty 120 PSI, Alligator Clips, Twist Chuck

VIAIR 88P that I used to use, but not with the 400H-A that I use now. The 88P has a lower duty cycle.

 

Haha. Thanks for that explanation that cooling fins are for cooling!

Yeah it’s a trade off I guess. On the one hand one wants to place the plastic parts of the compressor away from the heat of the engine to avoid embrittling and degrading them, and on the other hand doing so may hobble the performance of the compressor. This is one of those frequent situations where we tend to make seemingly common sense assumptions that are without any basis in actual fact. (I’m not pointing the finger at you, Electroboy. I’m as guilty as anyone in this regard. Maybe more so.) What we don’t know:

• What is the temperature under the hood?
• How much hotter does the end of the compressor closest to the engine get than the end that’s farther away, and is the difference significant?
• What is the temperature threshold above which the plastic switch housing will begin to degrade?
• Is the under hood temperature high enough to shorten the run time of the compressor?

So anyway, based only on my fantastic web of untested assumptions, I would prioritize preventing the decomposing of plastic over diminished performance.

 

@57HotrodVW

Sweet rides, both! Love those Corsa wheels. Rare to see 'em. Thanks for the pics. Yes, big fan of V-dubs. Something about those curves and boxer engines. Mmmmm. Had a '64 all original euro import(was second owner no less) in Sea Blue and a '67 Ghia running dual 48s on a 2176. The Ghia had OG Rivieras, a 2.5 drop, and a penchant for pissing off v8s. Miss them both.

 

Well, I had to run a quick test to determine my under hood temperature. I used a ThermoWorks Dot BBQ thermometer and cable probe mounted at the typical passenger side location for an on-board compressor. And took a 30 minute highway drive to heat things up. Outside air temperature was 61°F.

I found that driving at highway speeds the under hood temperature was only 5°F higher than the outside air, referenced to the 4R temp sensor dash readout.

After stopping and idling the temperature rose over several minutes and stabilized at 103°F.

After turning off the engine the temperature rose over 20 minutes to a peak of 119°F before decreasing.

This was just a quick test to get a rough idea of the air temperature at the mounting base typically used. YMMV.
But it shows that there is quite a bit of air flow under the hood while driving, and from the radiator fan when idling. From what I’ve read about other cars I expected higher temperatures. The 4Runner temperature at that location seems to be within the range for most quality compressors.

 

That is awesome! Data trumps daydreams. Facts crush fantasy. You, sir, win today’s award for Most Prestigious Forum Member™, and our gratitude.

So the conclusion is that it doesn’t get hot enough under the hood to matter which way the compressor is mounted.

I’m trying to remember … isn’t there some other accessory that gets mounted under the hood that folks worry about overheating?

 

Do I detect a slight note of facetiousness in that response??