Can someone explain VAPOR LOCK to me..

[badmix]

My truck acted funny today. I drove it around, made a few stops. At one stop I was inside for about 20min. came out and the truck wouldnt turn over, it acted like it had a dead battery, Ive got dual batts and I checked voltage, plenty of juice. I flipped the switch to combine them for extra power and it wouldnt start. The neg. batt cable was getting really hot and a lil smoke from tryin to start it. After a few minutes of scratching my head, I turned the truck over and it started up. Ive since turned it off and started it up every so often and it fires right up. When I was first having the problem. the motor didnt want to turn over at all.

Now just b4 I turned the truck off the first time b4 it wouldnt start any more, I went to a place where some high school kids were washing cars for cheap. So, I sat there and let them wash my blazer. I didnt turn the truck off, just idled with the A/C on. after they were done, I drove the truck about 5 miles and turned it off. That is when it wouldnt initially start. But now it starts every time.

So I was thinking maybe vapor lock? I dunno. The batts are fine and the alternator is charging properly. I also just tuned the truck up (new plugs, wires, cap & rotor).

even though its fine, id like to know why it did what it did.


Thanks

 

[BGKYK5]

Doesn't sounds like vapor lock - it wouldn't effect cranking. Vapor lock isn't related to your starter at all. It is when the fuel in your lines (or possibly fuel bowls if carbed) boils. The fuel vapor in the lines prevents liquid fuel from reaching the engine. If it happens it is usually on a really hot day when the engine is shut down hot and you try to restart it before it cools. With vapor lock, it would crank OK but not start.

 

[badmix]

yea, after some research that is what I figured. It is hot out , but the truck wouldnt crank, it acted like it had a dead ass battery. But then whatever happened , happened and it started and I didnt do anything, kinda weird.

 

[BKinzey]

"Wash" or at least rinse, your K5 again and see if it happens again. Sounds like electrical problem and if a wire is getting hot that could be a poor connection. Maybe the water is causing a short?

Probably should check your connections anyway.

 

[greg mgm]

I had the exact same thing happen to my 78 truck, and it was caused by the starter. After I put headers on my truck, I had regular starter problems...until I bought a Powermaster mini starter. Problems gone

Even if you don't have headers, your starter could be beginning to crap out. Doesn't sound like vapor lock though.

Speaking of vapor lock, my truck cut out because of it. On long trips, or uphill climbs it would have short hesitations, but it didn't stop the engine completely. After re routing the fuel lines away from the headers and insulating them, problems gone again. The factory lines were 1 1/2" from the header...not good!

 

[gone huntin]

You need a starter and make sure it has a heat shield. Hot soak no start problems are common on starters that are on the way out.

 

[badmix]

What is a good brand name starter? What about Napa?

Im guessing the truck is starting to show its age now. I just replace the ORIGINAL U joints a couple days ago. And now im guessing the starter?!?!?

Oh well, beats having a car payment.

 

[gone huntin]

My personal choice is to get it rebuilt at a local rebuilder with good quality parts, especially if it's an original Delco starter.