1989 Arriva with Mercruiser 5.0 high idle after carb rebuild

MikeyArriva

Petty Officer 3rd Class
Joined
Mar 28, 2012
Messages
96
Hey guys, been a long time since Ive been in here but havin a new issue with the ol girl.

OK SOO.....After owning this, my second Arriva for 2 years, near the end of last Summer I was sick of how it seemed under powered and tricky to start, so i started by changing the cap and rotor, plugs and wires. While doing the wires one by one I came to notice that the #2 and #4 wires were backwards..as in #2 wire was going to #4 cyl and vise versa... how ridiculous is that.. and i drove it like this.. no idea how long it was like this before i bought it or what they may have done to make it run somewhat decent besides sluggish out of the hole.. Now it was running like ive never seen. jumps up on plane instantly and runs around 45mph at 4500rpm but.... I began noticing shortly after that when I started the boat I was getting a bunch of black smoke out the back and sometimes it was tricky to fire up. it would start but then die or start to die before I pushed the throttle down in neutral to keep it going. As i left the dock sometimes I would have to give it quick shots of throttle to keep it from stalling out. once it warmed up though it seemed fine. I pulled it out and brought it home and shut her down for the winter.

So its spring now and a couple weeks ago I ordered a new carb rebuild kit (rochester quadrajet 4 barrel) and rebuilt it with a friend that knew how to rebuild them. Everything went smooth in the rebuild. every screw we took out we counted the turns and put everything back the way it was. I did an oil change the other day and while warming it up its noticeably different.. starts right up with just a couple shots of throttle and then back in neutral, very little to no smoke coming out the back so i was very happy.. I left for a bit to let it warm up and when i came back I noticed that it was now idling at 2000 rpm. I tried turning the idle screw on the left of the carb (right side if i'm looking at it) but it made no difference. Is there something i'm missing? is there something that may have been done earlier to make it run while the wires were backwards that would cause it to run so high now that that everything is proper and clean? or do i just need to have it in the water in gear to adjust the idle or what.. sorry if this is just rambling. I want to give all the info i can of everything i've done and what i'm seeing. I know with my old Arriva and the force outboard it had to be in gear in the lake to set the idle which didn't make sense to me and i don't know if this is the same but i'm a little worried popping it into reverse off the trailer or even floating it and going into forward at 2000rpm. is there something else that might be going on that i can look at or change or do in the yard before i take it up to the lake next weekend. thanks guys!! I have manuals for the boat and the mercruiser but apparently its just the owners manual and not the maintenance manual so im not sure what to do except turn to you. Cheers with an ice cold Bud Light from up here in small town Ontario Canada
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,766
Is the throttle cable allowing the throttle blades to completely close ? Is there anything with the linkage on carb that won't allow throttle blades to fully close
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,090
every screw we took out we counted the turns and put everything back the way it was.

Ayuh,..... That's a Startin' point,.... Not the finish line,..... It needs to be properly Adjusted too,......
 

MikeyArriva

Petty Officer 3rd Class
Joined
Mar 28, 2012
Messages
96
Ok I figured that was the case. I'm not a mechanic just learning everything as I go. Can the adjustments be done in the driveway on the muffs or does it have to be in gear in the lake?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,090
Ayuh,.... Ya get it pretty close in the yard, 'n try it on the water,....
If further adjustments are necessary, find a helper,...

I don't really do Quadra-jets, but others will be along,....
 
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