tune up trouble

[ispurpleafruit]

I have a 1967 Chrysler Courier with a 120 hp mercruiser. I was doing a tune up and when I checked the timing, the mark was an inch away from the little tab that shows where to adjust to, also the tab dose not have multiple marks. It is just a thin metal tab with a line "scraped" into the paint. When I adjusted it to where the marks line up it ran rough and when I gave it gas it backfired a lot and stalled. I put it back to where it was and it runs ok, but it idles at like 950-1000 RPM. It gets around ok but when it comes to pulling a tube or a skier it really lags. does anyone have any ideas. Someone mentioned I should tune my carberator. I have tuned small go-cart carbs before but nothing this complicated and my manual seams like it is assuming I already know how to do this so it doesn't make a lot of sense to me.
Any Ideas

 

[mkast]

Re: tune up trouble

What manual are you using?

 

[Glastron_V210]

Re: tune up trouble

Check your timing marks:

1) Remove #1 cylinder spark plug
2) Rotate the crank by hand with the approprite wrench until you feel compression (air escaping cylinder
3) Insert screwdriver, and slowly rotate engine in the forward direction until you feel the piston contact the screwdriver. Continue to rotate until the piston reaches it's apex.

Your tdc mark should be pretty darn close. If not, make new marks and time to that. Sometimes the harmonic balacer will slip and cause the timing marks to mislead you.

Chay