79 Dodge D-50 Sport, start/run issues

[Onehairysalad]

Help!!! Just replaced my spark plugs + wires & truck had rough idles at first. Then I fixed the gaps, which were off. I cleaned them up & popped em back in. I also did the wires 1 by 1 so as not to cross, or mix up. Truck then began to idle violently, & finally only for a short amount of time if at all. Does anybody know what the issue could be here? The truck ran like a dream before any of this. Only work I've done is change the radiator, and fill it with thermocure. Also I got new hoses for it and made sure they were secured. Also I got a new pre heater hose & slapped it on, seemed a bit long, but I still got it in there. I also washed out the engine bay with degreaser and water multiple times, but I've driven it out of town since then. Not sure where to go from here!!!

[tortron]

Sounds like a pair of leads has been switched tbh.

- just saw you washed down the engine bay. If the cap and leads were wet you could have had them earthing out.

Double check your lead order. That they are correctly seated in the cap and on the plugs, that the cap is seated on the distributor,
Try again with everything dried out

[geezer101]

Water will get in anywhere it can and cause mad misfiring. Also check the press fit of the leads and the threaded caps on the spark plugs. I've had them loose straight out of the packet before. Check the posts in the distributor cap and the end of the rotor button for charring/burnt spots. A little fine wet and dry to brighten them up will help conductivity.

[85Ram50]

If its water in the Distributor cap WD40 was made for exactly that purpose. The WD stands for Water Displacement. Spray the contacts with it and that should solve the problem if it is water in the cap.

[Onehairysalad]

I also ordered some cheap champion spark plugs, so will replace those. Just worried I could've got some irreversible damage to my baby. I'm hoping this all turns out ok!

[Onehairysalad]

Alright sprayed it all with wd 40 & wires are sitting in the sun to dry out some. I'll let you all know how it goes!!! Thanks guys! You all the mvps!

[85Ram50]

For future use, when you spray WD on something electric and wet it is usually good to go right then. Blowing things dry with air is helpful too.
BTW I learned this the hard way whenever you hose off the engine or engine bay, start it first and keep it running until you are done and for a bit after.

[Onehairysalad]

Damn! Yeah I dont know what I screwed up here. Threw some new spark plugs, made sure the wires were in correct order and attached correctly. Car still rough starts violently shaking, and if lucky will run for a few seconds & slowly dies out. I guess next I'm replacing the cables again, I'll have to figure out how to test the distributor & coils next.

[Onehairysalad]

For info, idk if helpful, I used champion RN11YC4 spark plugs. I checked the gaps and all were set at .4.

[Onehairysalad]

Extremely frustrating because this thing ran better than my newer cars that I've had in the past. No issues whatsoever, always started without hesitation.

[85Ram50]

If the parts guy chose them have them confirm they are for your truck.
I feel for ya. I had this sort of thing happen to me on my 85 when two things happened. The balancer belt broke but I did not know it and I "rebuilt" the weber carb. It never ran well since except after I put in the new carb. I've still got to dial it in and right now its not wanting to start easy.
I would slowly go over what you did standing there reenacting it to see what wires or hoses you may have knocked off.

[tortron]

Do you still have the old plugs and wires?
It's hard to diagnose over the internet but it sounds like it's running on 2 or 3 cylinders.

Pull all the plugs.
Try a known good plug (probably the most tan and dry one that's currently in the engine)
Try that plug in each plugwire, holding it against the engine block to earth.
You are looking for a strong blue spark from each wire.
This will eliminate the distributor and coil as the issue.

If all the wires give a good spark from the good plug then try your other plugs in one and see if all your plugs give a good spark.
If there's a wire that doesn't give a good spark with a known good plug, then the wire is the problem
And same goes for the plugs, if you get a good spark on one plug, but no spark on another then the plug is the problem

That's a basic way to to it, sometimes the issue isn't immediately obvious (plug wires that fail when hot, plugs that spark in one orientation, but when in the engine are the wrong way, or a weak spark that gets blown out under compression) but don't worry about that for now.

The other possibility is that the timing is out. Did you loosen the distributor at all?

[Onehairysalad]

I think I should order some NGK spark plugs, I currently have 2 sets of champion plugs, 1 from rock auto & 1 from autozone. They are different lengths when measured side to side, maybe I should get a part# specific NGK, and clean out the wells & threads. It's even possible that some debris could have fallen down the well. I really thought that a spark plug change was much more simple.

Also, I did not remove the distributor, but I did remove the cap, and I wiped the inner workings down and sprayed it all with wd40. Also I cleaned & sanded all of the terminals. I tested the wires against the block & got spark from all 4. I dont quit understand how to test the spark plugs with the wires, as you mentioned. Do I remove the spark plug, and connect it to the wire with the key in the on position? Or would I have to crank to achieve that spark?

[geezer101]

Remove a spark plug, take the plug lead that was connected to it and reinstall the plug, ground the plug terminal to the engine and get someone to crank it over. If you can see a consistent electrical arc in the spark plug gap, you have a good ignition source from that lead/plug. This is a basic test for spark/ignition faults. Plugs are important (like stating the obvious here...) You need the correct plug type - threads too short, the electrodes are out of reach of the air fuel charge. Threads too long, risk of mechanical damage, pre-ignition of air fuel by carbon build up etc. Gap is too wide, weak spark. Gap is too close, not enough area of exposure to ignite the air fuel charge. Then there's the actual heat range of the plug, tuning tricks like plug indexing and dynamic engine tuning... there's a real science to it.

I would use NGK plugs. They are as OEM as you can get. And get the ones specifically listed for your engine type. If you suspect the coil hasn't been changed in 10 years (or ever...) get a good quality new unit. A coil will on average last about 10 years before it starts to break down. If you can upgrade to a transformer type coil with the ballast resistor as a package, they are superior to the oil filled can coils.

[Onehairysalad]

What is this? I just found this broken CONNECTOR to an air hose, connected to the ignition coil. 20200620_135629.jpg20200620_135629.jpg

[85Ram50]

It is part of the emissions system for the Mikuni carb On my 85 there are two of them with two hose connections each.

[Onehairysalad]

Do you know what part that is? I'll have to order a new one.

[geezer101]

Doubt you'll find one. Try a spot of crazy glue and reconnecting the broken barb. The ignition circuit won't connect up without a vacuum on that barb. This thing has killed lots of engines and left owners freaking out on why their truck suddenly stopped running... option #2 - disconnect the hose, block off the source vacuum and bridge the connection to the vacuum unit so it makes continuous contact.

[Onehairysalad]

Thanks guys!! Could this be the source of all of my troubles?
Rough, violent idles, to no start, etc? I've replaced almost everything in the ignition system a couple of times, and by chance found this little detail yesterday.

[85Ram50]

See if this place still has those parts attached to the fender of one of their units. http://om.lindellauto.com/om/fvn/def...am+50&search=1
Seems like they would get left behind after removing the motor etc.
I have no idea who they are I just found them searching. I also do not know if it is affecting your motor as the emissions stuff was ripped out of mine when I bought it.
One more thing, if you need help to find a new or used one Mike Warme is in LA (I think) he is a member here try to contact him he might be able to help you find one. There are also a lot of good junkyards in the valley but you probably already know that

[geezer101]

Try unplugging it and bridging the terminals/pins across the connector. If it decides it wants to run - bingo, found it...

[camoit]

Sounds like a stuck EGR system. The Mekuni carbs used a slider inside the carb to controll EGR flow. The valve under the carb was to just open and close the gas flow. If anyone want's to clean out the EGR passages just get a bottle of Chevron Techron. Use that stuff with a brush or pour it in the passages. It will melt carbon. And what ever is left over you can put in the tank.

[Onehairysalad]

I will check out the EGR & PCV valves, and clean them out. My buddy swears up & down that my rough idle is due to the open choke. I'm just not sure if it has been open when It was running fine. Does anybody have any input on fixing the choke flap?

[geezer101]

Check the choke butterfly when the engine is cold before starting. If it's almost completely closed and the butterfly has a little play in it, that would be considered normal. If it's open when cold, the wax choke pellet may have failed but the engine will run fine when warmed up. A tell tale sign it has given up is a thick looking grease built up on the throttle linkages below the choke housing. If that is the case I'd start looking for another carb. It is 'fixable' but #1 - the replacement wax pellet assemblies aren't easy to find and #2 - I have never been able to successfully remove one without damaging the choke body in the process.

[Onehairysalad]

Before I get to work on everything, I want to show you guys the fuel pump? Looks like a line is missing, but idk what the hell is going on here. Also I have a pic of the choke butterfly, it stays fully open, but I'm safe to leave it this way? At least for the time being?IMG_20200701_105004.jpgIMG_20200701_104923.jpg