79 omc with 305 chevy tach will not work after hei conversion

[jasonrandolph]

I replaced my points with new hei dist with internal coil. Now the tach will not work. Which wire goes to the tach terminal on the hei? is it the grey wire that was previously on the neg side of the coil?

 

[Kainon]

Re: 79 omc with 305 chevy tach will not work after hei conversion

While I can understand why you would go with an HEI, Understand that it's not MARINE Approved.

the tach wire should be from the neg side of the coil, yea, but without lookin at a diag
You can hook a wire direct from the dist tach terminal to the lead terminal on the tach.

 

[jasonrandolph]

Re: 79 omc with 305 chevy tach will not work after hei conversion

Thanks for the reply. The dist I purchased said that it was USCG approved and is vented at the bottom. Are there no HEI distributors that are approved? I will try the grey wire from the neg side of the coil. If not, I will do what you suggested. Thanks for the help.

 

[Kainon]

Re: 79 omc with 305 chevy tach will not work after hei conversion

Sorry last I knew they weren't .. whose Dist did you buy?

i just looked at one "Marine HEI" and it looks like the old chev ones from the 1970's

all you would need to run that is a 12v wire from the run of the ign switch and tach wire from tach terminal to tach.
I know that style pretty well and my only other concern is that its setup for Marine,

no vac advance and mechanical advance weights & springs set for marine use.

 

[jasonrandolph]

Re: 79 omc with 305 chevy tach will not work after hei conversion

I bought it from AAA marine. The dist is called ChevPro. I have it currently set up from the old + wire from the coil but i am learning that it has a reduced voltage. Because of this, I will run directly from the ignition swith. I will still try the grey wire from the old coil for the tach. If that doesn't work, I will run the tach direct as you suggested. Thanks for your suggestions.

 

[Kainon]

Re: 79 omc with 305 chevy tach will not work after hei conversion

good luck, dont touch that wire while running, has a little kick to it.. Oh .. get yourself a Spare Ignition Module. It goes inside the dist.. quick easy replacement for those sudden losses of spark. Mine went ona trip to NY from near Boston, came a stop light 1000' after stopping for lunch and poof.. no spark. good thing K-Mart was walking distance. ( 1977 Chev Monte Carlo )

1979 does your engine have an ESA Module ? how are you going to connect that in? Did they Provide instructions?
and does that setup work with an ESA Module? or can you switch to a Mercruiser type setup?

hm...