Hey all, my neighbor has a beat up 1978 he's willing to give me for free. I ran a number of tests and concluded that the fuel pump is not pumping and the fuel line appears to be clogged.

I confirmed voltage to the pump and that the screws for the electric pump have continuity with ground. I also tried to run the pump without the fuel line to see if it would dump fuel. No dice.

eventually I tried to hook up an external electric pump but it won't pump through the old electric pump.

Additionally i tried to pump to the carb through the fuel lines from a gas can using an electric inline pump i bought. It appears the fuel lines are clogged because I couldn't get fuel to the carb. When I put a gas can/electric pump near the front and bypass the fuel lines that run under the rig it fires right up and runs.

To make matters worse, someone tried to replace the filler neck and when you try to fill the thing gas just pours back out! It currently has a little under 1/4 tank.

I'm kind of confused here, are the lines clogged and pump is dead or is something keeping air from exiting/entering the tank thus there is no movement there?

I'm open to suggestions and debating dropping the tank but really confused as to why I can't fill the thing. I know the owner had someone replace the fuel pump earlier in the year, it looks like they created more problems?

Any tips on how to troubleshoot it are much appreciated! I'm debating whether this is too big of a project, I'd like to be able to at least drive it home rather than tow it

 

Since it has been messed with and you have no idea what has been done, you probably should not try to figure it out at the sellers (donors?) location. I'd recommend getting it home and taking the time to find how it's SUPPOSED to be plumbed and wired and then blowing out the lines and whatever needs to be done to get it right. Then check over the engine and fluid levels and such.

Will the person allow you the time on his property or do they want it gone? Do you live close enough that you can drive it with your temporary tank and pump? Are you sure it runs well enough to make it home? If you're going to try to make it home, I'd at least have a tow strap ready and a fire extinguisher just in case. Do you think the cooling system is ok for the trip?

 

I've had no luck finding a diagram of the fuel and vent lines. Any idea where I might track one of those down? My understanding is that even a bad charcoal canister
should cause things to lock up like that?

I appreciate the concern/advice, truck is in the street in my neighborhood where its pretty normal to wrench on the block so not a huge issue. More hoping for tips on how to fix the thing than whether its appropriate to work on it in the location or not but ty

 

I wish I had some specific Chinook info. I've seen a few posts and build threads out there. I just did a Google search for Chinook Toyota with IH8MUD and Yotatech added and there's quite a few links to build threads. Might be your best bet for the info you need.

Good luck with it!
Scott in AZ.

 

thanks, i'll keep looking. I know the chinooks are basically wired/routed like stock trucks so with this thing its the same as any 2wd 78. hopefully I'll figure it out

 

Got the thing home by running a pump to a jerry can. If I blow on one of the lines to the charcoal canister it dumps gas by the tank? I'm confused on how that happened but I think it may be a clue that the tank is not venting. It did have a pressure regulator set to 5 which seems both high and unnecessary for a stock engine