78 E150 351W carbureted

So my van has always had a bit of trouble starting after a hard rain, and im 90% sure that this is due to moisture in the engine bay, more specifically the distributor. I replaced the distributor cap about a year ago and that seemed to help up until recently. I have tried opening the cap, wiping it all clean and then blowing any excess moisture out with compressed air or leaving a fan blowing on it for a bit. This did the trick up until this week.

I am wondering if the distributor cap is indeed the source of my problems. I can get the engine to turn over, but it never catches the spark and fires. I have checked and it is getting fuel, and there is def good compression, as this engine has ran great since i got it.

What should be my order of operations to diagnose this problem?

pull spark plug wire and check for spark. If it has spark, would that point to carb issues?

if it does not have spark, that would limit me to the distributor/cap/wires?

how do i test each of these? I would rather not spend the money for new wires, is there a simple test to see if they are still usable? The cap and rotor are cheap parts, should i just buy some new ones and see if that does the trick?

anything else i may be missing, im trying to solve this problem by the weekend so i can take the van out to tailgate, so any advice would be greatly appreciated.

9/26/2011 12:25:28 PM

For wires, I always assume that if they snap on firmly and they don't have any damage to the sheathing that they are still good. You can look at it in the dark to see if there is any arcing coming from the wires, but the van would have to run first.

Have you cleaned the points?

9/26/2011 12:42:48 PM

remove the spark plug. keep it plugged into the wire and touch it to a part of the engine bay that would serve as a ground point. Have assistant crank the engine over and look for spark.

9/26/2011 12:52:16 PM

I havent sanded them down yet, i just took a rag and wiped everything in the cap clean. The cap is under a year old, but the points are a bit corroded. So i just take some fine grit sandpaper and sand all of the corrosion off each metal point? Isnt the corrosion caused by arcing and by taking off more material(sanding) it would make the arcing worse? Do I need to re gap them? I was planning on replacing the cap and the rotor since it is cheap.


^cool, checking that when i get home and have a neighbor to give me a hand cranking it while i check

[Edited on September 26, 2011 at 12:55 PM. Reason : ^]

9/26/2011 12:54:34 PM

This engine does not have ignition points. Or rather, it shouldn't. It should have the old school Duraspark electronic ignition, and I'm willing to bet you have a module that's shit the bed. Where is this heap at?

9/26/2011 1:00:56 PM

haha, it is off of Kent Rd. And i wasnt sure what he was talking about with he points, mostly because i didnt see any points in the cap. You are right ZX, it has the old duraspark. any way to check and see if the module is bad? Is that tough to replace?

9/26/2011 1:12:47 PM

Id say its either the ignition module or something in the carb...the mix of water and gas making it not crank properly.

ZX knows the deal/process better than I would...good luck.

9/26/2011 1:21:42 PM

^thanks, but no water in the carb. The engine bay on this van puts the carb almost inside the vehicle under the doghouse. there are some holes in the vent tray that is below the windshield that i think is the source of the water on the distributor.

I havent had any carb issues to this point, so i doubt that would be an issue. This thing has run great and has only done this after hard rains and sitting for several days.

ZX, i am going to replace the cap and rotor when i get home today, if that doesnt help i may be getting in touch with you about the ignition module.



[Edited on September 26, 2011 at 1:45 PM. Reason : \/ your mom wanted it, you didnt have to watch or buy the speakers after i plowed her]

9/26/2011 1:27:26 PM

i think the problem is that you are a rapist.

[Edited on September 26, 2011 at 1:33 PM. Reason : seriously though, have you checked the candy supply? molesting vans run on candy.]

[Edited on September 26, 2011 at 1:36 PM. Reason : perhaps if you were a better DOGG Digital speaker salesman, you would have the money for repairs...]

9/26/2011 1:31:48 PM

Well maybe not the carb then, Im not aware of the layout of the van, I was just using the reference to water, perhaps in the fuel line somewhere to make it not start, but it would be sluggish instead.

Could very well be the dist. which I hate messing with those things.

again, good luck lol

9/26/2011 2:12:30 PM

Changed distributor cap and rotor, and after several minutes it started up. Im just wondering if there is another underlying issue since i went through a distributor cap in less than a year

9/27/2011 8:12:49 AM

Good to hear. Sounds like you'll be all set for when school lets out this afternoon.

9/27/2011 11:29:02 AM

Did you get touched where you pee as a kid? If you dont have anything constructive to say then fuck off. This isnt chit chat and we cant help you with your " my mommy is a whore and my daddy molested me" issues.

9/27/2011 12:19:06 PM

Well, you'll have plenty of time to live in a van down by the river when you're...LIVING IN A VAN DOWN BY THE RIVER!

9/27/2011 1:28:57 PM

Quote :

"Changed distributor cap and rotor, and after several minutes it started up. Im just wondering if there is another underlying issue since i went through a distributor cap in less than a year"

cracked ignition coil. cracked coils are notorious for malfunctioning in a moisture-rich environment but will work fine otherwise.

9/29/2011 9:47:42 AM

Thanks UnderPSI, i will be checking the coil this weekend. I dont want to be replacing the cap and rotor every 8 months.

9/29/2011 12:24:44 PM