Truck Died

[JohnB]

Truck was running beautifully today. Took a 30 mile ride. While sitting at a light, it just died. Tried starting and it just cranks with out any firing at all. Got towed home, checked carb and gas it coming out when pumping accelerator. There is a leak around the shaft in the carb but thats been there for a while. Poured a little gas down the carb and tried to start but nothing. Seems probable to be a spark issue? I haven't had it strand me for over 15 years and haven't done any work on it as far as tune up etc. It was running smoothly up until today. So.....any help on where to start on troubleshooting this. Coil, points, ballast resistor? I'm kinda lost at this point other than having it towed somewhere again. It gets driven maybe once a month and only short trips.

Thanks John

[PwrWgnDrvr]

Bummer, John!
in this order:
1. +12 at the coil
2. dwell, then points and condenser, rotor and cap
3. coil

[JohnB]

Bummer, John!
in this order:
1. +12 at the coil
2. dwell, then points and condenser, rotor and cap
3. coil

Thanks Terry, I'm charging the battery tonight and I'll tackle this tomorrow. Feeling kinda dumb while realizing I haven't had to do much to this truck in years. I've forgotten how to work on the thing. I'm sure it will come back to me. Like riding a bike, right?

[712edf]

Not alot of places to pull over in Alachua County either. Those roads have NO shoulder, or they didn't 35 years ago.

Bucky

[JohnB]

Not alot of places to pull over in Alachua County either. Those roads have NO shoulder, or they didn't 35 years ago.

Bucky

Yeah Bucky, it wasn't pretty. Friday afternoon rush hour. If you're familiar with the area; I was on Newberry road making a left onto 8th ave. In the outside turn lane. Traffic was backed up for a 1/2 mile. People were pissed and less than understanding. Oh well, it's not like I was enjoying it anymore than the people I was hanging up.

[jeffc57]

1st thing I would check, since your running points, is the ballast resistor. the engine grounds

[Jim100]

I recently had the same thing. The ballast resistor was toast but so was the coil.
jim

[JohnB]

Checked the truck this morning. Intake manifold valleys were full of gas. It was dripping out the throttle body shaft. It used to drip a small amount but not like this. I checked the ballast and it was 0.6 ohms resistance so that seemed ok. Cleaned the distributor cap and rotor. The points had spark so I buttoned it up and it started after some cranking. It stumbled a bunch and died again. Kept trying and it started running good again. Throttle shaft stopped leaking too. I'm thinking I had some dirt that got stuck in the carb and it flooded causing it to stall out. Float was probably stuck and gas just kept coming in. The carb is original and probably still needs a rebuild. Any recommendations on where to send it? Thought it would be electrical but turned out to be fuel.

Anyone know what the capped off black hose at the bottom left of the carb is for. Original owner put a short piece of plugged black hose on it. It has 2 hose clamps on it. I dont see any logical place for it to attach.

[Wildergarten]

Anyone know what the capped off black hose at the bottom left of the carb is for. Original owner put a short piece of plugged black hose on it. It has 2 hose clamps on it. I dont see any logical place for it to attach.

Looks like a positive crankcase ventilation (PCV) line. Do you have a PCV on one of the valve covers? If not, it may not be the original carb.

[JohnB]

Anyone know what the capped off black hose at the bottom left of the carb is for. Original owner put a short piece of plugged black hose on it. It has 2 hose clamps on it. I dont see any logical place for it to attach.

Looks like a positive crankcase ventilation (PCV) line. Do you have a PCV on one of the valve covers? If not, it may not be the original carb.

Mark,
Both valve covers have openings. Passenger side has the black cannister that should have a hose going to the air cleaner but the original owner has it going out under the truck. Drivers side has an elbow with a hose that dumps/vents under the truck. Original owner was an old timer who didn't like anything emissions related even back in 1970. For the past 20 years I have just left the truck as he had it. The carb has the metal tag with the number 4823S, which corresponds with a 1970 318 Dodge. Either it's the original carb or he switched the tag when he got a new one. Maybe the drivers side valve cover had a PCV valve at one time or maybe the elbow is the PCV valve? The hose caping off the carb is the same size as the one going from the elbow to under the truck. I'm going to get into the manual and parts book tonight and see if I can figure something out.

[712edf]

JohnB I am somewhat familiar with the area. I lived west of Alachua behind Sante Fe HS back in 87-89 & worked briefly at a pipe plant (it's gone now) in Newberry. Later I worked for Ray's Metal Works at the GE/Gates battery plant (it's closed too) on 441 east of Alachua. My dad worked at the Carlon plant in High Springs from 87-05. But I haven't been in that area in over 20 years.

I am also having issues with my old 2-barrel carb on my 75 W600 318. Just not as bad as yours. I never had a spark issue (until I burned some wires) but had fits with fuel pumps & the carb itself. If I trusted the new ones I would just replace it. I have rebuilt mine & believe it's beyond help.

Bucky

[712edf]

And yes the hose from base of the carburetor should go to a PCV valve at the valve cover & larger hose from black breather canister should connect to air cleaner/breather housing. PCV valves became common (required?) in cars in 1966. Possibly on gas powered light duty trucks then too.

Bucky

[JohnB]

Bucky,
That explains the fitting on the carb then. I need to figure out if the elbow on the Driver side valve cover IS the PCV valve. I'm not sure what advantage there is to bypassing the air cleaner and the PCV valve except for maybe the engine breathes a little better?
I live right in downtown Gainesville and it has grown a lot since you were here. I retired here because my daughter went to UF and decided to stay here so we moved up from south Florida. It being a college town makes it kind of crazy for an old guy but I'm making the best of it for now. Maybe move on when my wife retires.

[712edf]

The thing that I disliked about Florida the most was too many trees. I like some open spaces & a good view.

In the 80's one of the bars in Gainesville would have a midget tossing contest.

The point of a PCV valve & the valve cover breather arrangement is partially to allow for the pressure changes inside the crankcase due to the crankshaft whipping around & pistons slopping up & down. Before PCV valves engines often had a blowby tube. Tractors had them too. But the air that came out of them was deemed dirty so the government decided to suck it into the intake manifold & burn it.

A clogged or improperly working PCV will alter performance. It affects the air fuel ratio. I have actually had an engine leak oil when the PCV was clogged.

Bucky

[712edf]

As to where to send the carb, over on the power wagon advertiser site I have a thread titled "My W600 failed me today" or something to that extent. I believe it's in the 72-93 sub-forum. Anyways one of the other posters (oldndcctrucks) offered to rebuild it for me. Apparently he has a knack for them. Also there is a website for Mike's Carburetors which sells parts & kits for just about everything old that you can imagine. Excellent knowledge & service.

Bucky

[PwrWgnDrvr]

Crankcase pressure is built up by piston blow-by of combustion gases. Rotating crank and pistons moving up and down does not change pressure.

[JohnB]

"In the 80's one of the bars in Gainesville would have a midget tossing contest."

Bucky
No midget throwing contest anymore but they do have a bar with hatchet throwing. Thanks for the explanation of the crankcase ventilation.