Diskotrek - 1975 Argosy 24

[kidjedi]

Originally Posted by bkahler

As far as I know 55 psi is the recommended pressure.

Thanks, Brad. Any idea how to keep pressure in the bag when there's a giant hole in it?

One inflated fine, the other just hissed at me.

Drove it around the block a few times to day... mostly because reverse wasn't working and I had to go around the block to get it back up the driveway. Hopefully the tranny is just grumpy after sitting so long. Part of today's journey was to just get the fluids flowing and see what's going on.

Next thing to research is the choke mechanism on the side of the carb. It doesn't seem to be moving as freely as it should. I think someone may have bent the piece of metal that fastens it to the head. It seems odd that it is so finicky about where it needs to "seat," but then the thing that holds it in place is about as thick as a piece of tin foil.

[PeterH-350LE]

Originally Posted by kidjedi

Messing around underneath today, moving wires, fixing the horn, cleaning out gunk, etc.

The airbags inside the front springs have enough air to make a sound when I let air out, but not enough to register on a pressure gauge. At what pressure do people run their front spring airbags? I can't find any information in the manual.

I have mostly seen them run at zero PSI , consider replacing them with

https://www.sdtrucksprings.com/index...hoCMb0QAvD_BwE

[kidjedi]

Originally Posted by PeterH-Airstreamer

I have mostly seen them run at zero PSI , consider replacing them with

How adjustable are they with the airbags though? It seems like people talk about adjusting their airbags not only for the ride, but even for leveling a camp site. Is this not the case (are my hopes too high for such a thing)?

[PeterH-350LE]

Originally Posted by kidjedi

How adjustable are they with the airbags though? It seems like people talk about adjusting their airbags not only for the ride, but even for leveling a camp site. Is this not the case (are my hopes too high for such a thing)?

Never heard of anyone using the front air bags inside the spring as a leveling device. The lift with working bags is very minimal.

I remember someone mentioning manual adjustable rear air bags and not using the leveling valve(s).
I think that the front airbags belong in the same category as the cockpit windows, which would be the Airstream Hall of shame

[kidjedi]

Originally Posted by PeterH-Airstreamer

I think that the front airbags belong in the same category as the cockpit windows, which would be the Airstream Hall of shame

I hesitate to write this "out loud" since I can't knock on wood over the internet, but for some reason my cockpit windows seem to work great. I've heard lots of horror stories, so... should I be worried?

[martin300662]

I think it is better to describe the front airbags as 'assisters'.

1974/1975 20ft units didn't have them (Bella still doesn't), 1977 they got added, to stop front end dive under braking.

They really are not air suspension, you would need different bags and remove the springs for that.

[bkahler]

Originally Posted by kidjedi

Thanks, Brad. Any idea how to keep pressure in the bag when there's a giant hole in it?

Duct tape?

[kidjedi]

For ease of finding later, here are a couple threads containing good information on replacing the airbags (if you can't afford to replace the springs with better ones).

https://www.airforums.com/forums/f15...html#post94192

https://www.airforums.com/forums/f15...tml#post221115

Those links go to the specific posts where the "good stuff" regarding how to replace the bags begins.

[kidjedi]

It is infuriating how difficult it is to find specific (but simple) information. I'm trying to figure out where to place my jack to replace the front spring airbag. The manual has a simple diagram that really isn't very helpful at all. For the front, it looks like you are supposed to put jacks on the front A-Arms (I don't even know if that's what they're called). But where? Not to mention... obviously you aren't going to put the jack *on* the A-arms, because they move. So do you put the jack on the cross piece that bolts to the frame (the cross brace that the a-arm pivots on)? On the frame (the flat piece towards the center or farther to the side through the a-arm pivot point)? The location for the jack seems like something important and useful enough that there would be a photo in the manual or a mark on the frame where you are supposed to put the jack!

[kidjedi]

Well... that was a little more difficult than I expected, but the airbag is in. I will definitely at least get a quote next time I have to do that.

[PeterH-350LE]

Originally Posted by kidjedi

Well... that was a little more difficult than I expected, but the airbag is in. I will definitely at least get a quote next time I have to do that.

Congratulations on getting the bag in. What puzzles me, besides the high friction design, is the fact that the bags get severely crunched when installing, unless you pull the spring apart.
You should be good for a couple of years

[kidjedi]

Originally Posted by PeterH-Airstreamer

Congratulations on getting the bag in. What puzzles me, besides the high friction design, is the fact that the bags get severely crunched when installing, unless you pull the spring apart.

Yeah. Jacking up the wheel to change the bag at least extends the spring to the same length as the deflated bag, but getting the rubber pucks in at the top and bottom (especially keeping the top one oriented correctly) is certainly no easy task (actually, the bottom one wasn't that bad). I think there are several who reported back on their efforts to state that the upper puck may or may not be in the correct place (if there at all). My experience was the same. The upper puck is *in* there, but whether or not it's flat like it should be, or shifted onto it's edge and now folded in half smashed into the upper part of the spring (most likely)... I have no way of knowing.

I will say that a couple of pipe clamps and a drill with a ratchet bit is definitely the best trick for squeezing the bag enough to get it through the tiny hole in the a-arm (much more effective than zip ties or the "string" suggested in the instructions). I also used grease instead of the "liquid soap" suggested. I don't know if it will degrade the rubber bag faster, but it seems like something that will keep the bag lubed is better for inside a spring that is intended to move up and down. I didn't end up using very much grease. Maybe five or six pumps from the gun for the whole job.

Finally, I don't know if I placed the jack correctly (hopefully others can chime in for anyone else seeking the same answer), but I put the jack on the cross-brace of the A-Arm where it bolts to the chassis. Putting the jack on the flat part of the chassis (between the front wheels) was not only problematic because of the slope of the chassis plate and the possibility of the jack slipping, but also had the jack in too far to the center, so that I was essentially jacking up the whole front of the vehicle. The diagram in the owners manual shows the jack position touching the a-arms at the base of the "A," so that was another thing that led me to that jack placement. I started with the vehicle up on my 2x8 ramps (with 8" of lift), and then I jacked the vehicle up until the wheel on the side I was changing was just barely lifted off the ramp. As a pianist, sticking my fingers through the spring to manipulate the bag was a terrifying endeavor.

But it's done, and now the Diskotrek sits level. And since the kit had two bags, I've got a spare for the future. The kit also came with fittings and hoses to attach to both bags so they can be inflated from a remote location, but for now I just threaded a valve back into the bag and will be inflating it directly.

[kidjedi]

So here's a question: how much fuel pressure should be at the carb?


I purchased a vacuum/pressure gauge to see if my vacuum lines were alright, but on a lark I hooked it up to my fuel line at the carburetor today and I'm only getting around 1.5-2 psi at the carb. I placed the gauge right at the Carter P4070 pump and the meter read 5 psi. All the rubber from the pump to the carb is new, so I thought maybe there was an obstruction in the hard line. I blew that out but got the same reading. I had a bunch of fuel line left on the spool, so I completely bypassed the hard line and took a reading up at the carb (through about 6 feet of 5/8" rubber fuel line). Still 1.5-2 psi. The P4070 is supposed to run at 4-8PSI, so that seems within spec when I tested right at the pump, but is this not a strong enough pump to push fuel at the pressure I need up at the carb?

[PeterH-350LE]

What fuel pressure should I run with my new carb?


Carburetor Fuel Pressure by Manufacturer


Each style of carburetor has a fuel pressure range where they perform the best. The owners manual that came with your carb will give you set-up and tuning instructions. However, you can use the table below as a basic guideline.
Carburetor Style Recommended Fuel Pressure
Summit Racing 5 - 7 psi

Autolite 4.5 - 6.5 psi

Holley 5.5 - 7.5 psi
Edelbrock 6.5 psi (max)

Demon 5 - 6 psi (at idle)

Quadrajet (street engines) 4 - 5 psi

Quadrajet (performance engines) 6 - 7 psi

[PeterH-350LE]

It was always my understanding that a pump at the fuel tank for carburetor engines only serve as a secondary to the mechanical fuel pump to prevent fuel starvation and vapor lock.

[martin300662]

Originally Posted by PeterH-Airstreamer

It was always my understanding that a pump at the fuel tank for carburetor engines only serve as a secondary to the mechanical fuel pump to prevent fuel starvation and vapor lock.

On Bella the Carter P4070 is a replacement for the mechanical pump, that is removed and blanked off.

At some point I will refit the new Carter mechanical pump as I have had one instance where a flat battery meant the P4070 could not deliver fuel, to allow the engine to start - sort of chicken and egg situation....

[PeterH-350LE]

Originally Posted by martin300662

On Bella the Carter P4070 is a replacement for the mechanical pump, that is removed and blanked off.

At some point I will refit the new Carter mechanical pump as I have had one instance where a flat battery meant the P4070 could not deliver fuel, to allow the engine to start - sort of chicken and egg situation....

Martin, so the question would be where is your 4070 located? Close to the tank or close to the carb? We may have to wait for Brad to get off work to chime in on this. This is one of his specialties

[martin300662]

Originally Posted by PeterH-Airstreamer

Martin, so the question would be where is your 4070 located? Close to the tank or close to the carb?

On a little 20ft the tank is only about 6ft from the carb so everything is relative! But it is is about midway.

[kidjedi]

Now I'm getting 2 psi on both sides (in/out) right at the pump. This is a brand new pump. I guess the gauge might be wrong?


edit: and my pump is right at the tank, though that's only about 6 feet from the carburetor

[PeterH-350LE]

here is a 1 star review from someone:
1.0 out of 5 stars Will deliver 2.5PSI at idle if that’s what you need
Reviewed in the United States on February 5, 2019Verified Purchase
Provides less than 3PSI at the Carburetor at idle. Replaced all fuel lines in my truck with 3/8” NICOPP all the way from tank to carb to try to help it and it still won’t get to 3PSI. Don’t bother if you need 4-5PSI like most carburetors require. My truck can’t pull a trailer up a hill without cylinder head temps rising to 270F due to leaning out cylinders. Get yourself a better pump. This shouldn’t even be for sale.