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Planemech · 10-18-2010, 04:21 PM

This is all about taking out a vintage RV without going through it completely. I had a sudden need to go to Tampa, FL on work and had planned to use the RV for this kind of trip. I have a 25 ft '83 Ford E350 Rockwood.
I had to have 6 new tires put on, the cruise control fixed and other minor service. I had experienced the standard Ford E350/460 engine fuel flow problems and thought I had that fixed.
One day out I had to replace the entire exhaust system. The muffler had collapsed and I had no power. Climbed two Montana passes at 25 mph.
NOTE:The exhaust shop found the tail pipe necked down from 3"to 2" and the muffler itself had a 7/8" pipe. They made it all 3" with a high-flow muffler. The 460 never felt or sounded so good. These engines need to breathe. That's why so many put headers on. The shop did not recommend this because of the heat already generated in the doghouse.

A couple of days later I stopped for lunch in a small town in Missouri and came out to find a puddle of green under the engine. By 5:30 I had a new water pump ($650).
The next day I started experiencing power loss again but it was more of a miss and starvation. Out of curiosity I pulled off the distributor cap - corrosion everywhere so I managed to find an Autozone on the way. Parts yet to be installed.
On day 6, I was trying to make Tampa withpout refueling and got the tank down to about 1/4 (aftermarket gage that I don't trust. Power had been gradually decreasing on hills and was getting bad enough for me to pull off at an exit. I thought maybe I was getting a form of vapor-lock with all the ethanol fuel. I let the engine cool, had lunch, and then decided to put some more fuel in. All the power I could ask for! This vehicle came with an in-tank electric fuel pump and no engine-driven pump. The tank pump must have failed in the past, they did that,so there was a frame mounted pump installed. I believe now that the power loss is due to either inability of the pump to draw from below 1/2 tank or from actually sucking air at that stage. Either way I'm going to have to drop the tank. One suggestion I got today is to use the tank drain hole (if it exists) to install a small standpipe and outlet to the pump. That way gravity would help instead of hinder. Comments?
I'm here in Tampa for 6 months so have time for fixes.

RedneckExpress · 10-18-2010, 04:48 PM

How much did the exhaust overhaul cost you? My old Dodge's exhaust has basically fallen apart, the muffler no longer has a bottom (Rusted and blown out), the pipes are all close to paper thin and waiting one good bounce to bust them off, tail pipes gone.... etc...

After reading through a number of older RV service manuals for the line alot of them said to go up to a bigger pipe diameter.

W8RLM · 10-18-2010, 04:55 PM

When I had a 1976 Mobilel Traveler on a Chevy chassis, I experienced a severe loss of power. I found out that there were TWO screens in the outlet of the exhaust pipe. Rust flakes from the exhaust pipe and the muffler had piled up behind the screen and almost plugged the exhaust. I used a screwdriver and a hammer to knock out the two screens. When I started the engine, it "blew its nose" and a big cloud of rust came out of the exhaust. The engine ram fine afterwards.

Something else for anyone to check.

W8RLM - Bob

Planemech · 10-25-2010, 06:11 AM

The exhaust repair was about $400. Yours might be a little more. I still had some 3" pipe. If it's a 460 you also want to check the exhaust manifolds. They are famous for cracking.

decodancer · 10-25-2010, 06:44 AM

I can so relate. My 83 Midas on a GMC just died on the 100 mile trip home the day I bought her. Didn't have roadside rescue then so it took 4 hours to finally get a towtruck that could actually get us home. Fuel pump that time. $400 including the tow. Second attempt a week later was just to the local Home Depot for remodeling supplys. One block from home, loud noises were coming from the engine. Water pump, might as well change the timing chain. Whoops, we damaged the radiator on the drive to the mechanic, fan was also bent so those had to be replaced. My $2900 low mileage great deal was getting very pricey. I was also told I needed to fix the exaust manifold, the former patch job was not going to hold. Actually got one long trip in before that happened. $1200 later and I had a great running vehicle. Did need ball joints to pass inspection this year, $600 more but I'm so emotionally attached, it doesn't even matter at this point. I've had several great trips and have the longest one planned. She may be old outside but mechanically she's almost new.

sknight · 10-25-2010, 06:52 AM

Electric pumps don't suck very well, that's why new vehicles have gone to in tank pumps.

I'd worry about possible clearance issues if you mounted a pickup in the drain plug. One good bump or road gator and your line could be snatched off. How close is your pump to the tank? If it's a good distance away then you'll be better off moving it closer to the tank or adding a low pressure pump close to the tank to feed your pump further forward.

How they eliminated the in tank pump is very important. It needs a clear run to about 1/4" from the bottom.

Since you're going to have time to work on it I'd try to go back to an in tank pump setup. It really does work very well and despite obvious concerns about electrical things in gasoline the environment doesn't have any oxygen. No oxygen, no chance of fires.

Planemech · 10-25-2010, 08:15 AM

I was thinking of going back to the in-tank pump if I have to drop the tank. I think there are shops here to do that. I'll probably wait until near time to leave because I'll have to get a hotel room and move out of the RV.
For all I know they just added the chassis pump and pull right through the old one!

RedneckExpress · 10-25-2010, 10:23 PM

Quote:

Originally Posted by Planemech

The exhaust repair was about $400. Yours might be a little more. I still had some 3" pipe. If it's a 460 you also want to check the exhaust manifolds. They are famous for cracking.

Nope, don't think Dodge did a 460, they did a 440, 400 and 360, I have the 360, and there are many days when I wish I had the 440.

Exhaust manifolds are in good shape, they get a good looking at whenever I'm doing the oil and other than being a light rust color, they're fine, the pipes coming from the manifolds to the cat are in good shape, just rather narrow, its not till after the cat that the pipe really goes downhill.

Quote:

Originally Posted by Planemech

I was thinking of going back to the in-tank pump if I have to drop the tank. I think there are shops here to do that. I'll probably wait until near time to leave because I'll have to get a hotel room and move out of the RV.
For all I know they just added the chassis pump and pull right through the old one!

Alot of electrical in-tank pumps are what are called pass-thrus, in that you can pull fuel through them via another pump. Personally, I'd go with a heavy duty aftermarket external pump setup and regular pickup straw and float in the tank.

leadman · 10-25-2010, 10:54 PM

The in tank pump would be your best bet. One reason the factories use them is the fuel in the tank helps cool them. It is recommended to not go below a quarter tank of fuel for this reason.
If you decide to go with the external pump you can check the pick-up in the tank by hooking a hand held brake bleeder type vaccum pump to the line and working the pump. You should be able to draw fuel into the resevoir for the vac pump if the line is good.

JimElliott · 10-26-2010, 09:58 AM

My 87 "Chebby 454" had the in the tank pump only with NO provisions on the engine for a mechanical pump.....
Now my 83 had a mechanical only pump and was a PITA (AC Delco) so I added a "Carter street/strip" electric which caused even more problems since the mechanical could not draw e'nuf fuel thru it on a heavy hill climb.
The "Edelbrock 1722 mechanical pump" eliminated the problem 100%
Now for the good part......Harbor freight has a platform lift (500 pounds) that is about 9" wide and 20" long for about $125.00 that will make life easy for you and I use it at the shop for rolling those heavy batteries and other uses....
My tank (80 gal) is 50" long and by simply removing the center strap (1 of 3) you just slide it under and remove the other 2 straps and drop it down and roll it out...
When you have it down it makes things simple like changing out all of those rubber lines including the genny fuel line & filter....
I do replace those rubber lines with fuel injection rubber...

Jim