My 59 F100 with a 351 Windsor and Rochester Quadrajet carb has just arrived from Florida and although it starts it will not run or idle. The truck also seems to have had fitted an AC Delco electric pump fitted. Any ideas before I start stripping stuff out as I think it's either the carb needs the jets cleaning or the choke is sticking on. It seems the Rochester carb, dependant on the model, may have an automatic choke...I have linked some pics of the carb.....any of you fellas recognise an obvious problem? Also the AC pump seems to run for a while....maybe it's low on fuel but I don't think this would cause it to start then cut out because it will start again straight away and keep running if I "blip" the accelarator. Thanks Lee
Rochester Carb & Fuel system - a set on Flickr

 

You've got something that's a mess, but I'm not sure exactly what. It appears you have two fuel pumps, an electric and a mechanical, and you really should only need one. I would figure out what the deal is there, and try to make one or the other work. The mechanical would be the simplist, imho.

I don't know anything about the quadra jet, and I've never been a fan of them, so I can't help you with that. I have no idea why anyone in their right mind would go to all the trouble to adapt that carb to a Ford. It appears the choke plate is partially open in the one picture, so it's not likely the choke is stuck, but I'm not there to play with it and watch it's operation. If the plate opens as the engine warms up, it's not stuck. Running better when you blip the throttle is a function of squirting a shot of petrol from the accelerator pump. So it sounds something in the idle circuits is non-functioning. It could be as simple as dirt in a passage somewhere, or a fuel delivery problem from your two fuel pumps, clogged filter, something in that realm.

I don't know if this is helpful, but at least it'll bring the post back to page 1, where a better carb guy than me might see it.

Good luck, and congratulations on getting your truck home.

 

Thanks Wayne
Yeah it struck me that two fuel pumps could be a little over the top as well as that nowhere in the line did I see any sign of a filter. The truck when shipped is recommended to have a small amount of fuel...I think there may be some gunge dragged in somewhere. I think I'm going to drain things down, clean through as well as clean out the carb thoroughly then fill with fresh fuel and see what happens.

The Rochester carb seems to be popular on marine installations but like you I was not convinced it was good for the 351 Ford

Any recommendations should I take it off and start again? Holley something?

 

Rochesters are OK...in your pics is 099 a filter or an AC electric fuel pump. Also...check the big fitting that is the fuel inlet...there might be a filter in there which is a slug of sintered brass.

Check the fuel pressure with a test gage to see what your system provides. Maybe your previous owner put in the electric pump to prime the system after it had been sitting for a while so that he wouldn't have to crank the starter enough to fill the carb float bowl.

If you get fuel and it won't idle start by looking for a vacuum leak (possibly a bad gasket between the carb and the manifold or a disconnected vacuum line). Sometimes you can find a vacuum leak at the carb base by spraying some WD40 or carb cleaner around the base of the carb while it's running. You can see it getting sucked in and you can sometimes hear a change in the sound of the engine.

 

It's an AC electric pump...I cannot see a filter anyplace. I have spoken to the previous owner and he says.... "I did have issues with if the truck sat for more then a few weeks without being started that they carb would freeze up and I would have to get it cleaned. I'm wondering with it being flooded like it was by the driver if the fuel is sitting in the carb and became stale. The fuel filters would clog about once a year"

When I switch on the ignition the AC pump continues to click which suprises me as I thought if I was not cranking the engine/drawing fuel it would not click.

Do you mean the big fitting on the side of the carb? Is there a filter in there?

I've ordered a new gasket set for the carb and have bought some carb cleaner spray. I will check the vaccuum issues.

I'll be acting on all the advice Saturday and hope to get the old girl running then !!

 

Yes...in your first picture (img_0095), it shows the fuel line where it attaches to the carb. The large brass fitting (one inch or so wrench size) holds a filter element. If it's there it is a sintered porus metal slug about 1/2 inch in diameter and an inch long. Those filters can be plugged up without really looking very dirty. You'll be able to buy a replacement element without any problems at any of the auto stores....find the oldest parts guy there because the kid with the computer will want to know what model and year car to plug into the computer. You'll probably have to tell him that it's a 69 Chevy C10 pickup with a 305 V8????

Dan

 

There's a filter inside the carb (or at least there should be) where the line connects to the carb. You can see where it goes in image_0096, in the bottom right corner, under the vacuum line is the word FILTER. You may have a clogged filter, pull it out and take it into a parts store to compare.