Martin's Argosy Rebuild Thread

[bkahler]

Right, I forgot about all of the fuel tank work you had to have done.

What did you end up doing for a fuel tank sending unit?

[martin300662]

Originally Posted by bkahler

Right, I forgot about all of the fuel tank work you had to have done.

What did you end up doing for a fuel tank sending unit?

At the moment I have left the original sender in place, but because of the extra depth of the custom tank means it will show empty when there is still approx 2in of fuel left in the tank..... I don't think is a bad thing until I get a better idea of mpg.

I did get the inlet pump and strainer for the alternate sender but decided that is a task for another day!

[bkahler]

For the time being if it works then leave it alone!

I'd rather have a sender tell me I'm empty and have several inches of fuel left than have it tell me it's 1/4 and be empty!

[martin300662]

A good news/bad news day....and in future I will keep my mouth shut and not tempt the Airstream Gods.

Good news first - Bella is back!

All new brakes, bell cranks, suspension, steering overhauled, ball joints checked, and now steering damper in place and working great



First long run on the Centramatics, showed the improvement in terms of vibration - I can let go of the wheel and she carriers on in a straight line with no movement of the steering wheel - hurrah!





She drives, steers and stops great. Probably too well as the slide out dinette table shot out the first time I braked heavily.

Now for the bad news.

The aforementioned fuel gauge sender appears to have gone out on the way home and flipped the reading from reading nearly empty to open circuit (full). Hopefully just a wire come loose but who knows.

Worst she has decide not to change gear. Goes into drive and reverse fine but at the point that she should change up she doesn't.

Oh well progress is progress just now have some more 'essential work' that needs to get down before the motorhome get together.

[bkahler]

Martin,

Have you tried placing the shift lever in D1, D2 and D3 individually? You should be able to feel the shift lever give a little bit of feed back as you select each gear. Once each gear is selected does Bella move in that gear?

Also, the TH400 uses vacuum to shift so it's possible you have something wrong with either the vacuum hose or the shift modulator on the transmission.


If you do end up determining that your transmission needs to be removed I have what is supposed to be a freshly rebuilt TH400 that I just removed from my Argosy. When I bought the Argosy it supposedly had a freshly built 350 engine (never started) and the freshly built TH400. I also have a new torque converter to go with it.

The TH400 is of no use to me so if it will help you out I'm sure we can work something out that doesn't affect your pocket book

It might be your cheapest option to keep you going until you decide to do a power train upgrade.

Brad

[martin300662]

Originally Posted by bkahler

Martin,

Have you tried placing the shift lever in D1, D2 and D3 individually? You should be able to feel the shift lever give a little bit of feed back as you select each gear. Once each gear is selected does Bella move in that gear?

Also, the TH400 uses vacuum to shift so it's possible you have something wrong with either the vacuum hose or the shift modulator on the transmission.

I think the shifter linkage is working and adjusted correctly, as (following the instructions in the light truck manual) I have to lift to move from Park to Reverse, and from Neutral to Drive, D2 and D1 (although it feels like I could slide from Reverse into Neutral without lifting, same with Drive back to Neutral). Reverse engages reverse, Drive engages drive, D2 engages drive and D1 engages drive.

So I am suspecting the modulator; the issue is I can't find the modulator! It appears from the manual it should be on the drivers side towards the tale of the trans....there is nothing there. Also I can't find a vacuum take off on the intake manifold that routes towards the trans. Any suggestions?

[bkahler]

Originally Posted by martin300662

I think the shifter linkage is working and adjusted correctly, as (following the instructions in the light truck manual) I have to lift to move from Park to Reverse, and from Neutral to Drive, D2 and D1 (although it feels like I could slide from Reverse into Neutral without lifting, same with Drive back to Neutral). Reverse engages reverse, Drive engages drive, D2 engages drive and D1 engages drive.

That sounds right.

So I am suspecting the modulator; the issue is I can't find the modulator! It appears from the manual it should be on the drivers side towards the tale of the trans....there is nothing there. Also I can't find a vacuum take off on the intake manifold that routes towards the trans. Any suggestions?

Passenger side right next to where the dipstick tube enters the transmission.

[martin300662]

I still can't see the modulator but have a replacement reserved at the local NAPA....just need to build a pair of ramps like Peter's first to get Bella up in the air to get under her!

[PeterH-350LE]

Originally Posted by martin300662

I still can't see the modulator but have a replacement reserved at the local NAPA....just need to build a pair of ramps like Peter's first to get Bella up in the air to get under her!

Martin, no need for fancy ramps quite yet, you should be able to see the modulator from inside looking down on the passenger side. Usually there is a metal tube running up to the intake for the vacuum line. I would first check that you dont have any cracked rubber down by the modulator and up by the intake.

[bkahler]

Here's a another picture with a slightly different view.

[bkahler]

One thing still confuses me about your problem. You said no matter which drive selection you make it stays in the same gear. So in D1 (low) you're still in D3. That would indicate the transmission is not down shifting. I think when you manually select the gear the shift mechanism is forced to the selected gear. That doesn't seem to be working.

I'm not sure what that means

[martin300662]

Hi Brad, the issue is, when pulling away normally, and selecting the Drive position on the gear selector, Bella isn't upshifting based on engine speed. So she pulls away and I can run her right up to 50mph (with the engine screaming) and she does seem to upshift.

When I select L1 or L2 it goes into a forward driving gear but I haven't tried actually anything other than just moving forward to check it is engaged so have on idea what actual gear it is in (or if she would upshift to 2nd if I select L2).

I have assumed that Drive means selecting a gear where the trans would shift 'automatically between all gears (dependent on engine speed) whereas L2 still gives gears 1 and 2 (so could be used to downshift for overtaking if the trans is in 3rd) and L1 would restrict the range just to 1st gear (so should not be selected if already travelling above a speed that would over rev the engine) and really is only there to stop upshifting when pulling away on a surface with low traction, maybe this is wrong?

So Bella appears to engage a gear for pulling away no matter if I select Drive, L2 or L1 (so I assume 1st gear in each case) but does not upshift, even if travelling at over 40mph (which is supposed to be the max speed at which 1st should be engaged).

Does that make for sense?

[bkahler]

Originally Posted by martin300662

Hi Brad, the issue is, when pulling away normally, and selecting the Drive position on the gear selector, Bella isn't upshifting based on engine speed. So she pulls away and I can run her right up to 50mph (with the engine screaming) and she does NOT seem to upshift.

I added the word NOT in the last sentence above. I'm assuming that's what you meant to say.

When I select L1 or L2 it goes into a forward driving gear but I haven't tried actually anything other than just moving forward to check it is engaged so have on idea what actual gear it is in (or if she would upshift to 2nd if I select L2).

It would be interesting to see what it actually does when you make the above tests.

I have assumed that Drive means selecting a gear where the trans would shift 'automatically between all gears (dependent on engine speed) whereas L2 still gives gears 1 and 2 (so could be used to downshift for overtaking if the trans is in 3rd) and L1 would restrict the range just to 1st gear (so should not be selected if already travelling above a speed that would over rev the engine) and really is only there to stop upshifting when pulling away on a surface with low traction, maybe this is wrong?

You're correct about the Drive (D3). It should start out in 1st (D1) and then up shift through 2nd and then to 3rd.

When the selector is in D2 or D1 I'm thinking it should be stuck in the gear selected. In other words if you selected D2 it should strain to accelerate until it gets into the speed range where D2 would be appropriate. Selecting D1 should keep it in 1st gear.

I say the above based on what I vaguely remember happening with my Ford truck, different manufacturer so may not be the same. For some reason I'm thinking if you manually select D1 or D2 then that is the gear the transmission is in just like a manual transmission.

So Bella appears to engage a gear for pulling away no matter if I select Drive, L2 or L1 (so I assume 1st gear in each case) but does not upshift, even if travelling at over 40mph (which is supposed to be the max speed at which 1st should be engaged).

Does that make for sense?

Yep, makes sense. It sure sounds like the vacuum modulator is not working. Like Peter suggested it could be a vacuum line or it could be the modulator or worst case somethings wrong inside the transmission.

[martin300662]

Thanks for catching the typo Brad!

Just for info, can anyone explain how the modulator actually causes an action? It appears a plunger mechanism actuated by vacuum, but how does the plunger change gear? Does it push against a mechanism or have some sort of hydraulic action?

[martin300662]

So after a little "interweb" searching, I found this video that is pretty explanatory

https://www.youtube.com/watch?v=DrPF05kS154

So the gear selector limits the range (Drive allows all three gears, L2 just the lower 2, and L1 just 1st), the governor build pressure to actually change gears but the fluid pathways that are available are opened by the modulator.

So in Drive all three gears are available, governor speed builds pressure and the pressure pushes a piston that decides the fluid pathway, but only if the modulator is allowing it.

I also learned that if the trans has a problem under no circumstances am I going to be working on it!!!!!!

[martin300662]

This is what I found at the connection of the modulator vacuum line to the inlet manifold (which itself is a twin connector).



If that isn't bad enough the plastic T was broken and the connection would have been flaky at best.



Trouble is I can't find a piece of 7/32" vacuum line in stock anywhere (1/4" is to big and 3/16" too small for the inlet end).

At least I have a smoking gun.

[martin300662]

A temporary fix with the large ID line and a couple of cable ties = Bella is upshifting!

Just need to find the correct line now....

[Gregsch]

Bravo! Good for You. About time you got a break.

[bkahler]

Cool! It's great that it was something simple for a change.

It sounds like you might just need to order the correct size vacuum hose from some place like Rockauto. I pretty much order everything now days as it's just easier and doesn't waste my time running around. It seems that all the local auto parts stores all carry the same stuff and anything odd just isn't available locally.

It might be worth the effort to check all the other vacuum lines while you're in there working on it.

Brad

[martin300662]

The other vacuum lines look new Brad; just another case of a half-a#@*d repair, done by someone that took the quickest route to solve a problem.

I have found a few others whilst investigating this one; one in particular will sound familiar. Why do people install nice new fancy plug leads but try and use cable ties rather than replacing the broken wiring loom? Two of the wires were already laying against the exhaust manifod and showing signa ofmelting. One of the ones mentioned by Chiefair on your engine thread are on the way from Amazon.