HELP....Now I'm CONFUSED

[WATERTIMES]

Hey all !
Okay it's been a couple of days since I've been on,I didn't do the carb &
fuel pump til today and heres what I got, carb is clean,fuel pump
believed to be back in correct order, got my correct plugs today{J4C'S as well
as J6C'S}. I pulled out the J8C'S that were in it when I got it, I put the bottom plug in first, go to put the top plug in and it's too small, the thread size is too small. Whats up with that ?Do they make a bigger size thread in a J4C ? Help me.....Help me !!!! Any ideas as to whats up with this and how to work with it ? I was just gonna fire it up before stumblin block occured.

 

[F_R]

Re: HELP....Now I'm CONFUSED

The threads probably have been stripped out of the head and somebody has installed a Heli-Coil thread repair, which has come out. Look on the plug you took out, you probably will find it there. But you have to put a new one in because the installation tang will be gone. You will be money ahead to drag it by an automotive machine shop and have them put one in. It's a two minute job since it's already been tapped for it. The kit to do it yourself is expensive.

 

[5150abf]

Re: HELP....Now I'm CONFUSED

Check the plug you took out for a Heli-coil.

Sounds like previous owner stripped out the threads and had to tap it and the heli got stuck on the old plug.

 

[Vic.S]

Re: HELP....Now I'm CONFUSED

FWIW the "J" defines the thread size (14mm) and the reach (3/8")

there are a whole range of variations but all have their own code.

If you are interested look at the "Champion code" section on HERE

 

[WATERTIMES]

Re: HELP....Now I'm CONFUSED

Thank you guys again for info pertaining to my probs !
Well you were all right, the old plug had a helicoil on it. I probably did a wrong move,but I unthreaded it & put it on the new plug and she fired
up on the 3rd pull . I've got to pick up my carb rebuild kit today, I tried tuning the knobs {fast} was or seems to be runing rich, but can't get it to run
too lean. Listen to this{see if I'm crazy or not} I had sooo much exhaust
stuck in the barrel of water that I decided to blow it out by mouth....the engine started to run real strong, when I let it fill up again with exhaust it would run so-so, blow it out again it would run strong. Is this normal? I didn't get a chance to tune the slow speed because it was to dark to see anything so I will do that today. When I blow the smoke out of the barrel,it cleans right up and runs WOT great. I also wanted to mention that I was pokin around a parts site on here and was lookin at the cylinder head $, went down to spark plug list and they strongly reccomend using a J6J Champion plug, I'm using what I was told on here & it's the J4C
and I was also told to use the J6C's, whats the right answer to my needs ?

 

[F_R]

Re: HELP....Now I'm CONFUSED

We are still talking about a 1975 4hp, right? It is supposed to have J6J (now called J6C) spark plugs according to the factory parts list. Some older models used J4C so it's easy to understand the confusion.

Breathing it's own exhaust smoke will greatly affect the way it runs, as you have discovered. Even a tiny bit of smoke will affect it to some degree. You won't be getting that problem on a boat and will be able to dial it in properly

 

[ezeke]

Re: HELP....Now I'm CONFUSED

F_R is correct again, there is no reliable reference for anything but J6C as the current plug for your engine model. The best public listing for the plugs is at boatsetup.com and the BRP/Evinrude site has the same J6C plug as superseding the original J6J.

http://www.boatsetup.com/SparkPlugChart.pdf

Check the plug on the model-specific cylinder and crankcase diagram for your motor. You can then click on the number adjacent to the spark plug which will show the line item and original part number. Clicking the magnifying glass will show the superseding part.

http://shop.evinrude.com/

Product Details: Part Number:0593871Description:SPARK PLG J6C-8 PKPack Qty:8Dimensions:5.70 x 2.50 x 0.77 (in)Weight:0.12 lbsEquivalent Parts:N/A

 

[WATERTIMES]

Re: HELP....Now I'm CONFUSED

Hi F_R !
Yeah, your correct it's the '75 4hp. So you made me feel not so crazy,THANK YOU ! . The plugs I have are correct then. I got 2 of each yesterday J4C's-
J6C's, I wasn't sure of which one I should be runin with, right now I have the J4C's in it because I don't normally troll, but do ocassionally go slow.The way I have got the helicoil just threaded on my new plug....is that ok to do?
Hey, I'm seriously thinkin of goin into the marine mechanics school,can you, or someone here on the site tell me how many years it takes to become a mechanic ? What schools would be recomended ? As I said I'd be very interested in doing this profession, it's a challenge and it's fun ! NO KIDDING.
This seems very interesting to me.I may not be very good right now, but I would be when I learn in a school.