80 HP Merc, won't 'put out'

[cyber]

I have a 1979 80HP inline 4 that I just acquired.

Did a comp test and had it idling on the muffs before
I closed the deal, seemed to run great!

1st problem was gas squirting out the vent on the bottom
carb, so rebuilt the carbs and eliminated that problem.

So, off to the river to see how much faster my 14' is gonna
go with the 80HP instead of the 50 HP that was on it.

So I get it going (idling) like a charm, but as soon as I try
to advance the throttle, either slowly or 'pinning' it, it
immediately dies. Tried for over 1/2 an hour (engine would
start right back up and idle sweetly) but as soon
as I try to speed 'er up --BLAH!-- dead, just like I turned
off the key!!

Any ideas what my problem is????

 

[westexasrepublic]

Re: 80 HP Merc, won't 'put out'

yep very simple, adjust Idle screw on carbs

http://forums.iboats.com/showthread.php?t=167352

there is a lot of info in the link I posted, but basically do this (to all your carb needles)>

"Initial setting is: seat gently, then open 1-1/2 turns."

then adjust adjust open or closed to tune your motor how you like your hole shot and top end.

YOUR IDLE SCREW IS #7 on the diagram
http://www.boats.net/images/diagrams/Merc2/MERMAR/90672/15.png

 

[cyber]

Re: 80 HP Merc, won't 'put out'

Thanx Westex!!!
When I 1st mentioned the problem of gas squirting out of the carburetor, it was coming out of item #2 (in drawing)
on my bottom carburetor. I opened & closed it numerous times trying to get the gas to stop squirting out.
My favourite backyard mechanic told me it was just a vent, no big deal. So anyhoo, he's the one that
rebuilt my carbs and now I see by the cutaway drawing that #2 is in fact a 'jet'. Is this the high speed jet??
If so, then my problem is likely that I turned both of these shut (top & bottom carb)
So should I start by backing both these off 1 1/2 turns, take it out on the water, and try adjusting while moving
in forward gear?Sure would be nice if that's my only problem, I was starting to think I got hosed on this engine.
Thanx again for all the help.

 

[westexasrepublic]

Re: 80 HP Merc, won't 'put out'

well it is a vent that lets the gas out....but it is a big deal, because it prevents the carb from flooding. problem is the reason it was flooding. You had/have a bad float on that carb.

ALSO all this stuff is easy to overthink, calm, deep breath....

So should I start by backing both these off 1 1/2 turns, take it out on the water, and try adjusting while moving
in forward gear?

YES

 

[cyber]

Re: 80 HP Merc, won't 'put out'

ALSO all this stuff is easy to overthink, calm, deep breath....

Funny, we've never met, yet you know me so well!!!:redface:

So then #2 in the drawing is a vent, not a jet, correct??

Is the only thing adjustable on my carbs #7 in the drawing, aka the
'idle screw'?? And in the link you provided to the various
carb adjustments, mine would be the 1st one on the list, the 'single
S/S adjustable needle valve', is that correct??

Are the 'jets' fixed, non-adjustable?? Should/CAN I change them??
Arrggghh!! I'm headin' for an aneurysm!!!!

Do I pretty much ignore all but the idle screw?? One last thing,
in the exploded view the dotted line from item #7 kind of trails off
into limbo, is that screw located in the middle hole of those 3 holes
on the right hand face of the carb??

 

[westexasrepublic]

Re: 80 HP Merc, won't 'put out'

Do I pretty much ignore all but the idle screw??

YES that simple, you'll know it when you see it. Take the cowl or covers off to reveal the carbs

 

[Dave1027]

Re: 80 HP Merc, won't 'put out'

Won't put out? Well if you weren't such a cheapskate. Can't you at least spring for dinner and a movie?

 

[cyber]

Re: 80 HP Merc, won't 'put out'

Won't put out? Well if you weren't such a cheapskate. Can't you at least spring for dinner and a movie?

Actually took longer than I expected for someone to answer
with something along those lines!! Good one dave.