1978 Javelin runs too rich at idle.

[causeway]

Hi there, I have 1978 85 HP Javelin. I rebuilt the carbs etc and it runs too rich at low speeds. It fouls the plugs and lots of blue smoke. Once up on the water its fine. Gas Mixture is 50:1. Compression is fine. Replaced plugs and it works fine for a while then starts to foul again. When I check the plugs they are wet. When I check the plugs after a boat ride before I start to idle again the plugs are TAN. Can I solder the low speed jets and redrill smaller holes to lean it up at idle? Or any other ideas . The low speed jets are fixed and there is no other factory sizes. Thanks George.

 

[tashasdaddy]

Re: 1978 Javelin runs too rich at idle.

no you can. have you check your compression? low compression can cause that also. are all plugs wet, or just some of them?

welcome to iboats.

 

[causeway]

Re: 1978 Javelin runs too rich at idle.

Compression is good. All plugs are wet. Runs fine at all other speeds, but when cruisin' the channels it just spews blue smoke and runs really rough. A tech mentioned using rim-fire plugs??
thanks george.

 

[tashasdaddy]

Re: 1978 Javelin runs too rich at idle.

if you are not running Champion QL77JC4 gapped at .030. do so that is what that motors is suppose to have. not NGK, Autolite, etc. these other plugs are known to cause problems.

if you still foul out open your gap to .035

 

[causeway]

Re: 1978 Javelin runs too rich at idle.

Alright then, I will try that. I used champions with no luck, then tried NGK .
I will try the champions again and open gap. I will update my thread after I test it.
Thanks George.