1984 F250 ignition issues

So my 1984 Ford F250 auto w/a 460 will run for about 5-10 min and just shut off. I'm running a 600 cfm  edelbrock, replaced all the fuel lines and rear tank, replaced new fuel tank selector valve, all the fuel related relays and installed the fuel vapor/separator valve.

The MSD 6AL system looks very old and the engine compartment puts out alot of heat. I think its an ignition issue.  I recently replace the magnetic pickup, thinking it would solve the issue, only to have the truck shut down on me.

I'm thinking i should go back to the original electronic ignition system, but don' t know what came stock with a 460 at that year.

Is it just the Ignition Module?


Thanks

Do you have a tach?
When it does cut out, does the tach go to zero instantly, like you shut off the key?
Does it putter out like you ran out of gas?
How is your oil pressure?

Yes, in this year you would have the stock DSII system.
Gary has the EVTM posted up in resources.

Pay particular attention to the extra wiring for the Hot Fuel Handling in-tank pumps.
It's unique to the 460 and 351 H.O.

I had an in tank pump that would quit when it got warm, as in after I had driven for awhile.

Also what Jim touched on, I also had an intermittent cut out from a bad connection on the oil pressure switch for the fuel pump relay.

I have the 1984 EVTM, but don't have it on-line.  So I'll include the pages here 'cause there were some changes along the way and I want to make sure you have the right wiring diagrams.

It does have a tach. The truck just shuts off - but not like its running out of gas. I tried recreating the outage by pulling the fuel cut off relay. The truck sputtered and ran out of gas, so I've ruled out the fuel cut off relay. (and I recently replaced it with a new one).  

When the outage happens, it take a couple pulls to get it going again. If I wait a couple of min, it lights right up. This is why I think something is getting hot, and causing the cut off.

When it does go out, I checked the fuel selector relay (everything getting power) and most times I can hear the fuel pumps turning.

When you first start the truck cold, after (2) pulls you I can hear the fuel pumps charge the lines. It normally starts right up on the third - then 10 min later is shuts off all at once. When i try to start it back up I can't hear the fuel pumps.

I wonder how the Tach would effect it.

I replace both fuel pumps.

How did you find out your fuel pumps were bad? Just didn't hear them anymore?

Thanks Gary. What do you think about just swapping out the MSD for a DSII? Rock island has Ignition Control modules for around $30.00

I think I can use the MSD distributor. The truck still has most of the old wires, although most are cut.  

I think I'd try the DS-II box.  They work quite well, and it sure does act like a heat-related issue.

'84-460-Project wrote

It does have a tach.
I wonder how the Tach would effect it.

I was asking because the MSD unit only offers multiple sparks to a certain RPM, and then reverts to a single spark.
So I wanted to figure out if it happened as the unit switched modes.
Also many of these units (don't know everything about each model) have rev limiters.
So was considering that something had gone wrong with the pill.

But if you're willing to go back to the stock DSII, I'd try that first.

Shame about the hacked harness.
I would definitely be examining all of those connections.

After I found the bad connection, only the rear tank would cut out.

Found the bad pump by jumpering the oil pressure wires for the fuel pump relay and letting the pump run until I heard it stop. That is without the engine running so I could hear it better.

I couldn't find the Ignition control module in my garage stash, so now I'm on the hunt to find a good one. I plan to keep the MSD distributor. From the research I've done, it should work with a Duraspark ignition module.

Is there a difference between the Duraspark I and II? I found a Duraspark I on amazon for $38.00, but am having a hard time finding a II on line.

Rockauto has several ICMs between $20 - $50 for that year (but none say duraspark). I'm thinking they're OEM (Duraspark II comparable) and leaning toward those.

What do you think?

I know I have to go back through and trace/fix all the ignition wires. Its a mess.

Ignition Control Module goes on the drivers side fender well?

Another thing that's been on my mind: Fuel line placement.

Admitted rookie mistake - the current carb set up has the fuel coming in from the passenger side. I routed the new fuel inline up the firewall from the drivers to the passengers side, fitted the fuel separator(?) (T that restricts the fuel so it doesn't vaporize due to the hot conditions of the 460) on the passenger side. This is both the supply and return.

I plan to reroute the fuel lines to the front of the motor so I can capture the cooling fan effect. My only
worry is proximity to the exhaust manifold.

Do you think the fuel line placement could be contributing to the problem?

I can't tell you all the differences between DS-I and DS-II, but the II came out in about 1976, although it varied a bit by vehicle.  At the same time Ford introduced the larger distributor cap because the higher voltage of DS-II systems tended to jump across the smaller caps to the wrong cylinder.

And the module you want will have a blue grommet.  There are actually several DS-II modules, with grommet colors of black, red, yellow, green, brown, and white in addition to blue.  Plus, it goes on the driver's fender well/apron.

As for the fuel system, it may be possible to have the exhaust heat cause problems.  But what I would have thought for SURE would cause problems on Big Blue didn't.  The guy we call Florida Man () had the supply and return lines less than 1" from the driver's side header and it doesn't seem to have caused problems.  But it sure scared me, so I moved the lines and put a heat shield on them to make sure.

Would this one work?

https://www.rockauto.com/en/moreinfo.php?pk=49683&cc=1123816&jsn=568

Yes, that 's the DSII style module we all use.