I was driving fine at 60 then she started to stall. I let off the gas and it ran at 30 to 40 for a while then died. it started up and idled great, I got on the highway and same issue. I limped 60 miles home at 30mph. I changed fuel filter, tested the elec fuel pump. still same issue. any help is appreciated

First off, welcome to the forum.

What is the condition of the air filter? Do you have stock exhaust or headers? You may need to check the fuel lines and fuel volume. You mention an electric pump, where is it located in the system?

Also if the coach has been sitting around for a long time, the fuel pickup screen in the fuel tank might be clogging up with debris the more you drive and then it falls off when you stop.

_________________
Nick Taylor - Green & White 1974 Hall GTC.
www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com

thanks nick. the air filter looks good. it did sit a while. I put sea foam in both tanks filled up drove 100 miles then it acted up. it has headers. the elec fuel pump is on a toggle switch by the tank switch. it is mounted on the frame by the passenger mid frame. I found it when I changed the fuel filter. I don't understand the switch unless he just needed it at start up. previous owners burned up the first motor by putting diesel in it. the tank filter may be the issue. it only has 4000 miles on a rebuild and idles for ever just beautiful. is there a screen in each tank? switching tanks doesn't change anything. could it be bad wires , coil or plugs and shorting under stress?

The electric pump may just be a transfer pump between the two tanks. Mine only has a single 50 gallon tank so I have no switches. You'd need to check to see it still has the mechanical pump on the engine. It's on the right front of the engine below the alternator (right front is from sitting in the driver seat looking forward).

What did they do to remove the diesel from the tank(s)? Did they pull them out and clean them out or just siphon it out? I accidentally put diesel in my other motorhome from a gas can that a friend brought when I ran out of gas. I pulled the tank out to get it all out. I don't think a little would hurt anything as long as there was plenty of gas.

Each tank should have a screen on the fuel pickup. Sometimes they fall off. I had a Charger that would idle and drive great but every once in a while, it would have the symptoms you have. I had to pull the fuel line off under the hood that went from the tank to the pump and blow into it to clear the debris the pickup was getting clogged with. Eventually the tank had to be removed and cleaned out and a new screen installed.

You may have loosened up some crud in the tank with the seafoam.

_________________
Nick Taylor - Green & White 1974 Hall GTC.
www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com

that is what I thought with the seafoam. I can use my air compressor and blow the line back. if it works then I know I have to drop the tanks. I am in the middle of az desert now and it is an hour to a mechanic. if I can just get it going again long enough to get the tanks dropped. I have the records from all work done. this is well maintained. even new ac compressor. over 14,000 into this in the last 4000 miles. I don't know the story of how this ended up in impound?

Hopefully you can get it going well enough to get home. I don't know much about the history of your coach.

It was impounded? Is that where you bought it from?

_________________
Nick Taylor - Green & White 1974 Hall GTC.
www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com

I bought it from a guy who's son worked at the impound in Phoenix. I think maybe a repo. all the new work it doesn't make sense, I paid $5000. I have an appraisal from the paperwork at $21000. all the keys. the owners kitchen stuff and recipe box is still in it. I have all the paperwork on repairs and all manuals for the original and upgraded stuff. I think it was sold then reposed. I am at a lot in southeast az with my other rv and suv for winter. there is a rv repair about 13 miles away. I repaired a bunch of bad grounds today. I found some badly worn plug wires and rough plugs, I am putting new ones on tomorrow and blowing the fuel line back.

Strange, it is this same coach - http://www.hallgtc.com/hall_008.htm

A previous owner was trying to sell it here in California but then sold it to his son in Arizona and they had it for sale on Craigslist for a long time. His name was Joe and his wife's name was Bev. The father had done all the work on it and had the appraisal. He wanted to sell it for 20 grand and I told him he'd never get that for it no matter how nice it was.

Did you get all the manuals for it? Supposedly he had a user manual from Hall Coach but never sent me a copy for the site.

_________________
Nick Taylor - Green & White 1974 Hall GTC.
www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com

Depending on the type of carburetor you have, there is likely a filter screen on the fuel inlet. These things become easily clogged and should be checked. There could also be crud gorping around in the float bowl clogging up internal orifices. This stuff is usually a product of condensation congealing old fuel and bits of dirt and etc.

I'm betting that you do still have the mechanical pump and that the toggle switch and electric pump are there to push fuel from the tank(s) to the mech pump after the vehicle's been sitting long enough for the float bowel(s) to dry out. This is what happens with mine after about 2 weeks sitting.

Good luck!

thanks guys. I cleaned the carb. I put new plug wires on too. the old set was from another vehicle at some time. they were worn through to the core in places where no friction was happening. I blew the fuel line from the mechanical pump back and am only using the small tank. I also found a ground on the carb that was broke lose. I will download the pics to see if you can help. I did get all the manuals with this too. I am in my other rv in the az desert so it will take some time to download lol. On another note, we should have a get together down here some time. I have a lot rented until 3/16. It would make for a great picture. thanks for all the help.

I took it out and floored it for a while and it didn't kill. I didn't want to push my luck being alone on a holiday weekend. I am going to wait until Monday and give it a real try. If it is a carb issue I will be happy to put a new on . My other 78 dodge has a 440 and a new Holley and runs great. looking at the paperwork he put the electric in to help with gas running back into the tanks. looks like I need a new volt meter and a real oil pressure gage too. it is charging but it doesn't show it on the dash.

I found a letter from the VP of hall thanking the original owner for looking at the Hall. I will get this stuff to you guys with the original manuals.

So there was a solenoid on the fuel delivery line that is energized by the ignition switch that stops drainback? Nice idea! I always have to crank mine over quite a while before fuel reaches the float bowl, which is why most people have an electric pump back near the tank. Does yours have an electric or divorced choke?

the fuel pump is for starting for sure. I was turning it over after sitting 2 days and it needed the elec pump to get the gas up. I have electric choke. I fixed a ground on it. I think I need a new carb. what is the best choice. I put a Holley on my 440 and it is smooth. my isolator solenoid is shot or the huge fuse is blown. the alt is great but I,m not charging coach batteries. I am going to bypass the fuse to see. It looks like the original fuse and solenoid. the coach and front batteries are less than a year old interstate 27s. looks like they just opted for a fuel pump rather than a solenoid to stop drain back. it may have one that has just stopped working too. much to learn, on with the puzzle

OK. Then you must have a 4 barrel, right? The original was a Carter 2 barrel with divorced choke on an iron intake. I have an Edelbrock 1400 Performer on an Edelbrock Performer spreadbore intake with a squarebore to spreadbore adapter plate that woks great (after plenty of messing around to get it right). If I had my druthers it'd be TBI, but the cost is a factor. If you're OK with it, you can always rebuild the carb you have. Not all that difficult but you need a good place to do it. I rebuilt a number of Thermoquads before finally settling on the Edelbrock, which I also rebuilt.

I suggest that you get yourself a good multi-meter, preferably digital with automatic range finding, to help you deal with the electrical stuff that will surely come up. My Hall had 2 big cartridge fuses on the coach battery circuit, one of which is completely unnecessary, and both were of the incorrect type. You should start your troubleshooting by replacing whatever fuses are on the line with DC-rated fuses and see if the problem goes away. If not, you can start looking elsewhere. I spent quite a bit of time ironing out probs on mine and ended up with a modern, solid-state isolater and the same bunch of batteries that you have. Patience is required.

Oh. I thought that there was a solenoid in-line for some reason. The fuel pump is all you need, really.

thanks. The problem was the fuses. front was blown. I put in one slow burn fuse from my 2500 watt invertor and eliminated the rear. It charges now, I broke my foot so I have not had a lot of time for the carb. I have sprayed sea foam in the carb after start up for a few days and the carb is working much better. choke is floating like it should. I am going to change the carb filter and bring a spare and try a test drive.

Great! Be sure and replace that fuse with one of the right ampere rating before you forget about it. Inverters usually have very high current inrush, which requires a high amp fuse (or circuit breaker) - too big for the charging circuit. I've been keeping my eye out for a circuit breaker holder that can take just a single 100 amp panel mount breaker to replace the fuse, but maybe the best thing would be an old Trace fast blow fuse and fuse holder, because they have good shielding. I have tons of this kind of stuff kicking around the barn from my 35 years in the solar/wind business but most of it's pretty old and primitive by today's standards.

I opened the fuel line inlet on the carb and no filter inside. I cant see how any tube style could. I found a piece of varnish about 1/2 by 1/4" in there. the shape of the fuel line. It was solid like plastic. It must have broke lose when I put the sea foam in the tanks. I could see how that could have caused my issue. I have been running on my small tank since I started looking for a problem. I am going to add another can to the rear and hope it breaks up enough to not plug my line on the way to the filter. until then I am staying on the front. the varnish inside the carb was bad from burning that diesel. I am putting everything back together and trying to give it a whirl. Oh yeah I did get the right fuse from lowes and all seems good. I have two real deep cell 24s on the way for the coach. I have another 200agw solar battery hooked up to 2 100w panels for 110 invertor and inside led lighting . fingers crossed.

Great! Where are you keeping all these batteries?

im in kansas southwest ..xclose to oklahoma...texas...thinkjing of a hall reunion?

Long way from the West side of the Sierras!

I would love a reunion. It would give me a time line to get a new carb on this rig

I keep 2 24s both 75ah glass mats in the holding tray and the big charge tank under the table. it is the same set up I have in my class C. the big glass mat 150ah is only a little bigger than a marine but 80lbs. My panels charge everything in 4 to 6 hours. I have been off grid for over 3 years with this set up.

I also have to gp 24s in the sliding tray, same as the chassis battery, Interstate "deep-cycle" compromise specials. Having been in the off-grid solar and wind biz so damned long I first tried a pair of too-big AGM's, thinking that it would be pretty-much OK to mix metaphors with the FLA chassis battery. Wong. I knew better but had the AGM's taking up space in the barn anyhow, so what the heck? The problem is that the float (and bulk) charge points are different enough that the ever dependable (and not so bright) chassis voltage regulator would overcharge the AGM's but the combined resting voltage was too low for a healthy FLA in front. Cooked the big valve regulated bats in only 1 year and converted back to the lesser Interstates. What I REALLY wish is that they had bade the battery compartment tall enough to take a pair of T-105's. Nuthin doing, I'm afraid. So you don't have the propane tank in the under table compartment?

well I think I finally fixed the gas supply issue. I put in a new pump and it ran better. I had to dig into the carb. there is a small tube filter in the carb that feeds the jets. you have to take the top off the carb to get it out and clean it. I ran it up to 65 today and acceleration and down shifting while accelerating was good. I also found a small BB blocking the vacuum line to the vac advance for reasons unknown. I am going to try to run it 10 miles to the car wash to see if it plugs again. the rear tank is empty now. I have to change the fill neck and run it through metal flex pipe so the leaf springs don't rub through again
and I will clean it if I have too.

I have 2 AGM under my table hooked up to 2 100w panels and run a separate 110v system for lights and elec appliances. lets me use power tools too. I have my interstates on a smart charger plugged into the 110v system. 100% battery 100% of the time on both systems. has worked good for 2+ years now for me off grid

my propane is a 9gal under the front seat back behind a door

I will be heading north soon and will scan and post all the manuals I have for the gtc

How far North? My rig still has the original battery and propane setup with 2 X gp 24's in the slideout tray and 13 gallons of propane in the big space under the table. I just installed a "See Level 2" tank and voltage gauge to replace the POS original equip. The sender is stuck to the exterior tank wall (no penetrations) and the readout is from 0 to 100%. The coolest thing is that all three tanks, fresh, grey and black water, share a single pair of conductors. Amazing!! This is a very wothwhile project in spite of the kind of high price, but still < $200.00

It is running like new now. I will prob drive up to colodado for sure in june