55 hp carb adjustment?

[gunterm]

Hi everyone,

I just bought a boat last week with a 55 hp Chrysler, not sure what year but the boat is a 1971 so it's probably about that age.

Previous owner had a shop manual which was passed down to me, I want to adjust the carb but I need an accurate tach. Closest thing I could find was an 8cyl/6cyl one from an automotive store. Will that work?

Also if I could find the model of the motor and posted it here would I be able to get the year and some info about the ignition system? The cowl says "Magnapower" on it if that helps...

thanks in advance!

 

[keebler130]

Re: 55 hp carb adjustment?

http://www.tinytach.com/tinytach/index.php

May want to try this site. Have seen others here order from them,

I have a 45hp and am ordering mine Friday.

 

[eurolarva]

Re: 55 hp carb adjustment?

Tach is not that critical. If you are just doing the idle adjust so it is around 700 to 800 rpms. Set it as low as it will go in forward gear to get a smooth idle. If it starts to get rough or coughs kick it up a bit. I doubt an auto tach will work unless it is an inductive one. If your motor is from 1971 none of the parts places will go back that far most start at 1975 and newer. Chryslercrew sells parts manuals and service manuals that are in acrobat you can download or they can mail you. ID plate on yours should be around the carb on the lower cover stamped on a piece of metal about 1 inch by 2 inch.

 

[gunterm]

Re: 55 hp carb adjustment?

Got it, engine model is 5591

I messed up and mistook what I thought the manual said was the idle adjustment screw and turned something else. This one does change the idle speed though, I've attached a picture of it with the red arrow pointing to the screw.

 

[gunterm]

Re: 55 hp carb adjustment?

Pretty sure I got this right:



Also one more thing, I'm not sure which spark plug it uses, I found two different answers searching the web and looking in the repair book, its either an NGK B6HS or B8S.

There is a tach wire on the terminal block of the engine that goes through the harness up to the front, I found a tach that goes as low as 2 pole 4 cylinder.

 

[gunterm]

Re: 55 hp carb adjustment?

I made some changes to my above posts, bump.

 

[eurolarva]

Re: 55 hp carb adjustment?

5591 is from 1969. Try using L-82C champ plugs. Best bet for a tach is going to be an inductive type or you will have to contact tiny tach and tell them the make and model of your motor. just google tinytach and go from there.

 

[gunterm]

Re: 55 hp carb adjustment?

Cool, thanks!

Does anyone know what the screw in the attached picture adjusts? I messed with it thinking it was the idle screw and I've messed something up...

 

[bumpy]

Re: 55 hp carb adjustment?

I try to order from tinytach website and they want like 11 bucks to ship that tiny thing and cabellas no cheaper, so i found a website thats same price as tinytach website with your choice of shipping as low as 1.81 , which i took lol,

http://www.aircraftspruce.com/catalog/inpages/tinytach.php glad i could save you a few bucks dont mention it, and the ones they have are all resettable hours