Fuel delivery problem?

[IDBob]

Well I was given a 1970 Highboy a month ago. It had been parked from 1996 til now. Not trusting to use the gas sitting in the tank we hooked up a boat tank to it and it started right up and drove home the 20 miles from where we picked it up to my place fine.

I drained the dark yellow old gas out of the gas tank and put ten new gallons in and it starts up and runs fine when it's not moving. I put a new clear gas filter between the fuel pump and the carb. I also replaced the fuel filter on the fuel pump.

When I wind up the engine I noticed that there was air bubbles coming into the clear fuel filter between the pump and the carb and that the clear filter would empty out instead of staying full. The truck will idle, and wind up with no problems, but the minute you try driving it it starves out. It will still idle, but not pull at all without cutting out. It's simply underivable.

My first thought was a plugged tank. I hooked up the compressor and blew back thru the tank from the fuel pump. It acted like there might be some blockage so I drained the tank removed it and put a couple of gallons of paint thinner in it and sloshed it around a day or so. I cold still blow air thru the connection at the top of the tank and it seemed clear.

I put the tank back in, hooked everything up and the truck started right up as usual. But it still won't pull under power. I can idle anywhere in low gear, but push the throttle and it's a no go. I'm still getting the clear filter emptying out when I try to run it.

I'm guessing that I've got a partially plugged tank or a bad fuel pump. I've got another tank in my old 69, but it's got a different size fitting and I'll have to drill new holes along the edge of the tank to get it to bolt into the 70. I don't have a fuel presser tester so I'm going to hook up the boat tank we brought it home on and see what happens. Boy talk about frustrated.

I guess the problem could also be a carb problem, but it starts, idles and winds up fine.

Any ideas?

[fitzwell]

cracked rubber line under the truck??

I understand the "revs under no load" part. Could you possible be dealing with a vac advance that is inop as well?

in a truck that has been parked for 12 years, fuel lines would be one of the first things i'd look at.

[IDBob]

I didn't check the lines under the truck other than blow air thru them. I'll do that next. Thanx for the tip fitzwell

[Thunderfoot]

Like fitzwell said... sounds like it is sucking air somewhere in the fuel line... could also be a pin hole in the pickup tube in the gas tank as well...
If it ran ok on the boat gas tank hooked up I doubt that the fuel pump is bad unless it just went bad...

[IDBob]

Well I'm still frustrated. I hooked up the boat tank like we used to drive it the 25 miles to home on and It's doing the same thing, air bubbling into the filter between the carb and the fuel pump. Still won't run under a load, but idles and runs fine when you romp the throttle. I followed the fella whom drove it home and I'm going to ask him if he had any trouble when he drove it. He didn't mention anything like I'm running into when we brought it home.

The fuel filter empties when you do that, so I'm still thinking perhaps the fuel pump sitting there went bad. If it was a carb then I'd think I'd have idling problems and it just idles and runs great unless you try to drive it.

I hate to just replace parts til I find what's wrong, but for 27 bucks I can get a rebuilt fuel pump and 13 buck filter from Napa. I suppose a new fuel pump will at least eliminate that thing as the problem.

Any more ideas here guys, I'm going nuts.

[IDBob]

Your right basketcase I should have a fuel pressure gauge in the toolbox. The truck has a standard tranny. I'm going to Napa on Monday, our Napa is closed on weekends here, and pick up a fuel pressure gauge and see if what kind of readings it says.

What kind of vacuum pressure should this engine (360 FE) be pulling? I don't have a book on it yet. I've just not seen an engine that would start well, Idle well, go up the rpm scale so well and then just starve out when you tried driving it.

Must admit I'm not the greatest mechanic, but I've rebuilt my share of engines over the last 45 years.

[Thunderfoot]

Bob, It should have a fuel pump on it like this (picture below) in that canister on the bottom of the pump is a filter element inside. Use a metal type band wrench to unscrew it from the pump and the element is inside. You can get replacement elements with new gasket from the parts stores...
I bet that the bad gas in the tank plugged up this filter beings it wont run on the boat tank now...



filter for pump at Shucks for $2.00

[IDBob]

Thunderfoot I changed that filter out along with putting in another clear inline filter between the pump and the tank after I took out the gas tank and flushed it out with paint thinner.

I got a few rust flakes but not many and a bunch of brownish stuff when I flushed the tank and when I blew air thru the fitting at the top of the tank it seems to be open.

I've run pressure in the tank and can find no leaks between the tank and the fuel pump.

It still is bubbling air between the fuel pump and the clear filter. When running it seems the carb will suck that filter dry, but it keeps idling fine and will still rev up. I'm going to put a fuel pump pressure gauge on it Monday and see what it's actually pumping.

When you try driving it it will just die out when you depress the throttle. Let up on the throttle and it goes back to a nice idle. Pump the throttle and it wants to lerch and jerk as fuel goes thru the carb. Seems like it just isn't getting fuel under a load.

I'd think that there would be enough gas in the carb to keep from dying on initial acceleration, but that doesn't seem to be the case. The motor will idle and rev up fine out of gear. It just sounds great til you try to drive it.

Very frustrating. I'm not a carb tech, but as well as it runs, idle's, and revs up out of gear I just can't see it being a carb problem. Perhaps there is a problem with the vacuum advance. I'm going to check that next.

Oh as an add on I put in a new set of points and a hotter coil I had from my old two wheel drive 69 pickup.

[IDBob]

Well here we are at part 11 I guess. Put a fuel pump gauge on it and it said 1.5 to 3 pounds intermittently. Folks at the parts house said I needed a new fuel pump so I got one today. It came with a new filter so I'm going to bolt that up in a few minutes.

I had the friend come down and take a look at it and the thought it needed spark plugs so I put a new set in and he was right they were pretty glugged up.

Sure hope this solves the problem, I'd like to get it on the road before gas goes to 7 bucks a gallon. It was $3.80 locally today. Sure glad I'm out of the truck driving business.

I'd also like to thank all you guys that jumped in and helped me. This seems like a great place for us old Ford owners.

I found some really good info on which adapter to use to install a din radio and I'm planning on putting a 205 transfer case into it with the 203 box bolted to the front with one of the Advance adapters this summer.

This is going to end up just being a work rig for hauling my camping trailer out for hunting season and some fishing and hauling stuff for the place. Can't afford to take it to far anymore.

I've had the Mother Earth News plans for their Gasogen wood gas generator for a few years now and perhaps it's time to take a look at that again the way gas prices are going.

[IDBob]

The Highboy saga continues.

Well lets see, its' been quite a while since I've done much to this truck or got back to check out the forum. I rebuilt the carb and fuel was gushing up the two holes in the top of the carb. Read up here on what caused that and put a new float in and cleaned out the needle seat and it still did the same thing. Gave up and bought a carb rebuilt by Holly from Shucks and put it on. Did the new filter thing again because I'm still getting kinda brown gas through the see thru filter.

Started it up and it ran like a new truck. I drove it around town here for a few miles and other than the need to adjust the throttle linkage it drove fine. Decided to drive to town and pick up some plumbing I needed. It's 10 miles and this is the first time I've had the truck out on the road above 35 mph. Found out that the speedometer only goes to 40 and stays there til I drop back down below 40 mph.

Well I got to town, loaded up my plumbing and headed over to my old hunting partners house to gloat a little about getting it running. Got within a block of his house and it just died. I got it started by pouring some gas into the carb and hooking it back up to the boat tank, then it started spitting gas up out of the two holes in the carb like the carb I rebuilt.

Now what. The brand new carb had 15 miles on it and there was two brand new fuel filters in the line. Lets see?

New carb
New fuel filters
New points, condenser, rotor, Dist cap, wires, coil and plugs.

Well I'm pretty frustrated by now. Gave Shucks a call and they said they had to have a return authorization from Holly and gave me the 1-800 number to call them. This was on Saturday so the truck is parked on the street across from my buddies house til Monday when I can call.

Meanwhile I talked to a friend and he said that he'd need to rebuild the new rebuilt carb to make sure it would run right. He said I'd have a hundred plus in it.

Monday I called Holly and after they heard what it did they said they would not warrentee it and that it was something I had caused. I told him I talked to a mechanic and they wanted a hundred bucks to rebuild it and I expected it to run longer than 15 miles and could I please talk to his supervisor. He gave me a return number. I can't believe the carb with two brand new filters in the line sucked something thru that plugged the needle valve.

Got the new carb yesterday and bolted it on and hooked it up to the boat tank. A few ounces of gas in the top of the carb and it started right up and ran home on the boat tank. I did replace both fuel filters, the inline and the factory filter and sure couldn't tell if they were plugged from running new gas out of the main tank. To tell the truth I'm just afraid to hook it up to the main tank again. I'm looking at either a replacement tank now or putting in a new tank somewhere else than behind the seat for this truck. I'd sure like to get it running. Anyway for a free truck this one is sure frustrating.

Anyway it's back parked in my yard and I'm still not hauling the gravel I need in my driveway. Time to think about borrowing the neighbors pickup to haul in some gravel before it starts snowing here.

[fordman]

it does kind of sound like it needs a new tank and lines. or the old tank and lines cleaned out. it sounds like the carb was loading up. with its spitting gas up out of the vents. one other thing i can think of is if the inline filters were put one in the correct flow position. its just a guess. or maybe the rubber lines have a small air leak inthem and shot air to the carb and then sealed up and flooded the carb. it could also be a bad fuel pump doing that too.

[IDBob]

it does kind of sound like it needs a new tank and lines. or the old tank and lines cleaned out. it sounds like the carb was loading up. with its spitting gas up out of the vents. one other thing i can think of is if the inline filters were put one in the correct flow position. its just a guess. or maybe the rubber lines have a small air leak inthem and shot air to the carb and then sealed up and flooded the carb. it could also be a bad fuel pump doing that too.

Thanks for the hints fordman. I'm going to simply replace all the fuel lines and the tank. It's got a new fuel pump and I went out to check the inline filter to see if it was put in with the direction right and it was OK. I've already got so much money in this "free" truck that a little more certainly won't hurt.