1977 mercury 850 linkage problems

[ccarpen4753]

Ok, I have a 1977 850 thunderbolt. The issue I am having is that at WOT the carbs are only about a 1/4" open and the boat is very sluggish. I have poured over the threads regarding adjusting the linkage but still cant seem to figure it out. Do the levers adjust while the outboard is running and under load? First pic is in neutral and idle. Second pic is all the controls moved as far as I can get them. Pics taken when motor wasnt running. Need some help knowing what and if i need to adjust.
-Carbs are clean
-125psi on all cylinders
-good spark on all cylinders

I havent adjusted any of the linkage previously

 

[Chris1956]

Do you have a standard MerController? Is the throttle lever vertical (12 o'clock position), when the motor is in neutral and at idle speed?

The throttle lever should be at the 7:30 - 8:00 position when at full throttle. Is it there?

 

[ccarpen4753]

Yes i have the standard Mercontroller. Yes the lever is at vertical when at idle. Full throttle it only goes to about the 9 o clock position. I was looking at the linkage to the butterflies on my carbs and Im not sure if it is postioned correctly bc it doesnt want to open the butterflies.

 

[ccarpen4753]

ive been trying to find some pics or diagrams on how the plastic lever on the top of the carbs is supposed be linked to the throttle linkage

 

[Chris1956]

Unfortunately my service manual (with your motor) was destroyed by Superstorm Sandy. You might try this link. The site says this is not OEM, but it looks pretty accurate to me. There should be a picture of your throttle arm.

www.boatinfo.no/lib/mercury/manuals/mercury_1965-1989_40-115.html#/0

 

[ccarpen4753]

ya ive looked over that manual. I am getting close to getting the stuff set right. Everything says u need a timing light, which I dont have. I got it to hit WOT and plane good, but cant seem to get the low idle set. And when I put it in reverse it revs up really high, but in forward i have to put the warm up lever all the way open to keep it running. I have found a couple of guides to adjust the idle screws on the carbs but when I adjust them it doesnt seem like the rpms change at all. Getting real frustrated.

 

[Chris1956]

You will need a timing light to set the idle pickup and WOT timing. You will not have any luck without it, and could blow up the motor.

After you set the timing, use some fresh 50::1 fuel mix and set the idle mixtures at idle speed. It will take a couple of minutes to get it correct. 1200 RPM is about when the main jets take over, and the idle mixture has no effect. Obviously you will need the motor running below that speed.