burnt harness ??
- Thread starter boatin
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whatabudro
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boatin said:This site diagnosed my miss
I was wondering what causes the v/c harness to burn?
This is a quote from BJS in your last thread
"I'm going with the masses w/ the inector wiring harness usually it's a result of a bad glowplug that has damaged the harness."
You will have to at least change the bad GP so you don't fry your new harness.DO NOT USE AUTOLITE GP'S. They tend to swell over time then you can't pull them out. Stick with Motorcraft Beru's. Don't rush taking the old one out in case of carbon build up on the element.If you break it off chances are you will have to remove the head. If it's hard to come out use alittle carbon cleaner on it from the boat shop and work it out slowly. Good luck.
threejacks
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Must batteries be disconnected before unplugging wiring harness to check for burned wires?
BJS
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Nope you don't have to unplug anything as a matter of fact you can unplug the outer harnesses while the engine is running 
but don't lick the connector it'll shock the heck out of you.
threejacks most of the time you have to actually pull the valve covers off to find the damage. There are some times when there is such an electrical draw that the connectors @ the valve cover gaskets are damaged and you can check those easily but the harness that usually burns up is the under valve cover harnesses that go directly to each injector & glow plug
but don't lick the connector it'll shock the heck out of you. threejacks most of the time you have to actually pull the valve covers off to find the damage. There are some times when there is such an electrical draw that the connectors @ the valve cover gaskets are damaged and you can check those easily but the harness that usually burns up is the under valve cover harnesses that go directly to each injector & glow plug
BJS
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you can spray it around the threads and let it soak down into the cylinder. When you have the gp out turn the engine over to blow the carbon cleaner out.
Take and fill the depression taht the gp sits in w/ the carbon dissolver and then work the gp back and forth it should start getting such that you can turn it further and further.
When I did mine I had one that was fried that was problematic though difficult to turn I kept w/ the 1/4" drive rachet. I loosened it such that the threads finally came loose I couldn't pull it out so I just threaded it back in and ran it for another few thousand miles and then when I was in there for injectors I figured it'd be the time to try & get it out an if I broke it I had plenty of time to pull the head if I needed to. I found that I could clip the gp w/ a needlenose set of vice grips around the hex head of the gp and w/ a little rotational force and pulling straight out the gp finally came out.
Take and fill the depression taht the gp sits in w/ the carbon dissolver and then work the gp back and forth it should start getting such that you can turn it further and further.
When I did mine I had one that was fried that was problematic though difficult to turn I kept w/ the 1/4" drive rachet. I loosened it such that the threads finally came loose I couldn't pull it out so I just threaded it back in and ran it for another few thousand miles and then when I was in there for injectors I figured it'd be the time to try & get it out an if I broke it I had plenty of time to pull the head if I needed to. I found that I could clip the gp w/ a needlenose set of vice grips around the hex head of the gp and w/ a little rotational force and pulling straight out the gp finally came out.
threejacks
Full Access Member
Are the plugs on the wiring harness a snap plug or just a regular plug. I'm showing me age but with bi-focals I can't tell what kind they are and I don't want to break the harness?BJS said:Nope you don't have to unplug anything as a matter of fact you can unplug the outer harnesses while the engine is running
threejacks most of the time you have to actually pull the valve covers off to find the damage. There are some times when there is such an electrical draw that the connectors @ the valve cover gaskets are damaged and you can check those easily but the harness that usually burns up is the under valve cover harnesses that go directly to each injector & glow plug
BJS
Full Access Member
the plugs @ the valvecover gaskets you press down in the middle of the top surface and pull out. once you get under the valve cover it's a friction fit If I recall correctly I'll look @ my spare harness when I get home. The connectors @ the injectors have 2 types of possible connectors one with a wire bale attachment the other w/ clips on the side either move the wire bale down to release or GENTLY pry the clips away from the injector.
The glow plugs are a friction fit just like the spark plugs on a gasser. The oil serves to make great suction so pull w/ a pair of pliers on the actual boot not on the power supply wire.
The glow plugs are a friction fit just like the spark plugs on a gasser. The oil serves to make great suction so pull w/ a pair of pliers on the actual boot not on the power supply wire.
