hi, i am posting for my husband who is outside pulling his hair out. He has a 1989 F700, c429. He was having issues starting so he bought a new battery and new coil. found that the coil wires were coroaded so replaced those. still trouble so new brain box and wires. things looking upbut not idling correct so my brother tried to adjust timing and pulled off old vacuum lines that looked like they went no where any ways. idles great! but now put it into gear and it stalls every time. he wants a diagram of where there should be vacuum lines to make sure he has all of them hooked up that needs be. I cant find one anywhere, any suggestions? he also is looking for the codes for the timing. any help would really be appreciated.

 

Unfortunately I dont have any experiance with these guys, but I'll try to be as helpful as I can.
Does it have an IAC valve, and are those vac ports plugged? What are the TPS voltages (if you have one)? Was the SPOUT jumper pulled when the timing was set? Is the firing order correct? What transmission? It sounds like it might be a vac controlled trans/sensor issue.

The big guys had all sorts of configurations depending on the options. Pics (photobucket) are very helpful if you don't have literature/names of parts.
-Mike

 

thanks for replying: no, dont see iac valve. yes pulled wire under distributer cap when setting timing, firing correct order. transmission has R N D D2 and only one vac line to it and it seems fine. there wasnt any problem with any of this before,...i did forget to mention it started with heater core leak on sat, and temp not getting hot so he replaced both thermostats and put fix leak in for heater core and changed plug wires. new battery was put in on fri and new coil on sat also.

 

Big block aren't really my cup of tea. Only thing I can think of is a TPS or gear selector switch, if you have 'em, or maybe wire routing.
Does it stall when put in gear or when the accelerator is depressed?

And for anyone who was wondering, the 429 is the 460's baby brother.

-Mike

 

when put into gear only. idle is ok.

 

Seems like you have a C6 trans so the trans is not the problem.
Is there not an emissions label under the hood with a vacuum diagram?
Is this truck fuel injected or carb? If carb you could probably block off all vacuum pipes, except the one to the trans and one to the distributer (if there is one).
It sounds like the extra load on the engine when you shift to Drive is causing it to stall which could well be a vacuum leak problem (if carb motor) or ignition timing or carb choke problem.

 

nope, no label diagram. carburated. but trying to see if we are missing a vacuum altogether. diagram would be so helpful.

 

https://www.ford-trucks.com/forums/9...am-needed.html Click on this link and read the post by rla. Might be worth a try to do what he suggests, although I doubt it will have anything for a F700.
You could also try asking on the page for Big Trucks (look above this page on the main forum).

 

he now thinks he is missing a vacuum line on the back of the carb. still stalling after tinkering all day.

 

Did your husband ever figure this out? I'm looking for a diagram as well for the exact truck!