Two cylinders not firing after washing engine compartment

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Just got back to the truck after a two year hiatus. I got it running after a loose distributer wire and actually it was running pretty smooth. I drove it up and down the lane a couple time to get things cooking and then parked it in the drive and proceeded to hose down the entire inside and outside of the truck with water. It had been sitting in a mouse infested "tent" all this time and was filthy with mouse scat and dust and who knows what. Yes, I even hosed the interior of the truck as it's very bare inside and plenty of rust that a little water doesn't hurt. So I think at least. I also hosed down the engine compartment. Afterward, I turned on the engine and let it heat up to help dry. I did not notice any hesitation in starting or any rough idle. I think I then turned the car off after 10 minutes or so. A few hours later I wanted to move it and suddenly some of the cylinders weren't firing. I figured I got something wet and needed to dry it. Nothing seemed wet though I wiped down the plug wires and dist. cap inside and out. Still no luck. Ok, let it sit overnight. Today, same deal. I've narrowed it down to the cylinder nearest firewall and cylinder second in from radiator. There is no spark arriving to the plug as tested by grounding plug end to engine block. On the dist. cap, these plug leads sit side by side toward the passenger side of the car. I've checked other leads in these spaces and still no spark so not the leads. I've changed to a new dist. cap but no change. I'm getting a little fearful of the unknown. By the way, it's a Delco dist. from Mallory from way back when (no snark please). Any guesses, folks?

Many thanks!

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If there is no spark at the sparkplug end of the wire then my guess would be a bad wire.
 
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If there is no spark at the sparkplug end of the wire then my guess would be a bad wire.
You mean bad plug wire? I did switch out the wire with one that was firing and still now spark. Perhaps I got confused. Seems strange two wires would go bad at once? I started looking at the firing order and I'm completely confused now. As mentioned, the car was running great when I put it away 2.5 years ago and again yesterday after fixing the loose dizzy wire. But if I follow the firing order (see the pic) it sure doesn't appear to be correct. #1 is near radiator, correct? Where on the cap should #1 be? I don't have any numbers on my cap....
 

Steamer

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Cylinders are numbered front to back, 1 through 6.
Firing order is 1-5-3-6-2-4
You have wires 2 and 6 switched.
 
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Just checked again.....firing order appears to be correct to me. Did you get that from the pic? Please see the new pic. #1 I have circled in yellow. Is that correct? I also just swapped out one of the wires and can confirm that still no spark through the new wire....in position 2. What would a bad dizzy do? The fact that the two non-sparking wires are next to each other seems key. But what??

sparks.jpg
 
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Well I guess in that first pic indeed they were wrong. Hmm, in the new pic, however, they are correct and still we aren't getting spark in 2 and 6. Your help is much appreciated!
 
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I've water logged a few vehicles over the years but it sounds like you done the due diligence to ensure that all the water has been dried up.

Have you turned the engine over with the cap off to ensure the points are opening and closing on those cylinders? Could be flat spot.

> There is no spark arriving to the plug as tested by grounding plug end to engine block.

Have you pulled the plugs and looked them over? From that statement, I can't tell if you just touched the plug wire to the block or pulled the plug and did the test. They do tend to foul at the most inopportune times...how old are they?

Also, it's a good idea to replace the rotor when you replace the cap.
 
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I didn't see any reason to pull the plug as the spark is not arriving to the end of the lead...when grounding the lead to the engine block. I have not turned the engine over while watching the rotor. Certainly, the points are opening on the other firing cylinders, correct? If there is a flat spot, it is on the dizzy, yes? I don't see how it would have happened from washing the engine but who knows. The plugs are pretty new....well, they have very few miles on them but then sat for 2.5 years. However, the car was just running great before I did the washing. I do have some old gas in the tank, from 2.5 years ago....but I don't see how that would effect the spark through the leads. Maybe something is disturbing the correct seating of the cap? It does have a new condenser BUT I am not 100% sure it is the correct one. I didn't have a part number on the old one but I did have a model number for the Delco dizzy. Auto parts guys did some back tracking but it seemed a bit iffy. It certainly looks the same and fits. I'm under the impression there is not a not of difference on the inside of a condenser but....could it be the wrong one and cause 6 and 2 to not fire?
 
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Thank you. I'll try the WD-40, 1MAC. Cap seems quite dry inside, however. Dizzy, dirty battery terminals could cause this? Grounding strap...where would you suggest running this, from where the neg lead of the battery is on the frame to, say, the hoisting hook? ? I'm not sure I have one, but I might have run one in the past. I have never had an issue sparking leads of the head. I still can't understand how those leads would stop sparking after simply washing the engine bay.... I was thinking perhaps the cap is not seated correctly however I have taken it on and off many times and paid attention to re-attaching it. Maybe something broke off the dizzy.....
 

whitey45

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Water will collect on top of the cap in the wires, pull the wires out and wd40 or shop air. Also olugs can foul real easy after not firing after the wash!
 
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Coil, plug gap, dwell, etc. It could be a whole bunch of things. If you are shorted out, your coil will be kinda flat on the subsequent spark. Check the resistance of each distributor wire with a multimeter set to ohms.

First I'd clean anything that isn't, with abrasives, steelwool, wire brush etc.

Yes, the engine hoist hook is my ground. There should be one on the hook to battery, and, on the starter going to the frame. Try using a single jumper cable to restore a soild ground on the negative, for troubleshooting purposes. I'd go for new chrome on the hardware, even if it isn't Teq, just for the starter, the engine hook, etc.
 
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Thanks all. The truck was running just fine after washing. I turned it on and let it idle for 10/15 minutes to help dry out the engine bay. Since no spark is reaching the end of the lead on those two cylinders it seems pointless to worry about gap/carb/timing/valves.... And the engine runs on the four cylinders. I'm no expert but it seems it must somehow be the dizzy is not sending a spark down those two leads....why is that? Am I fair to think it's not the rotor or condenser or points since it is consistently the same two leads with no spark, 2 and 6? Is it possible for a dizzy to go bad in such a way as to only miss the spark in 2 and 6? And I have swapped out leads to those cylinders so that indicates it's not a spark plug lead issue. Does that not leave something in the dizzy? I have swapped out the cap, too, and the problem remained. Maybe the cap is somehow suddenly not seating correctly. Ground strap on the block, sure, but the engine was running just fine....
 
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Dizzy
Coil, plug gap, dwell, etc. It could be a whole bunch of things. If you are shorted out, your coil will be kinda flat on the subsequent spark. Check the resistance of each distributor wire with a multimeter set to ohms.

First I'd clean anything that isn't, with abrasives, steelwool, wire brush etc.

Yes, the engine hoist hook is my ground. There should be one on the hook to battery, and, on the starter going to the frame. Try using a single jumper cable to restore a soild ground on the negative, for troubleshooting purposes. I'd go for new chrome on the hardware, even if it isn't Teq, just for the starter, the engine hook, etc.
Dizzy, what do you mean "if you are shorted out" and "new chrome on the hardware"?
 
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a circuit with a short is what happens when your car wash solution is carrying an electrical current to ground where it isn't supposed to. The coil cant fire in short bursts, instead it is drained and it doesn't get enough voltage to carry an arc across the spark plug gap/contamination.

Where a screw is used to conduct a ground, it will work fine if it is cleaned of oxidation, I will 'chase' the tapped hole if it is rusted. I take that one step further and replace the original patina hardware, with fresh chrome, as it is more oxidation resistant. The only problem with that is, I keep the vehicle running by grabbing something from Hillman, and my engine bay gets cheap looking because I'm too disorganized to get the original ones plated or whatever, plus I loose patina and it looks like a hack job.
 

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