Re: 1984 Chrysler 90 HP
Well, you have a 4 cylinder 90. It is actually a de-rated 105. This happened when Chrysler started rating their engines at the prop instead of at the powerhead. Getting late so I will be brief.
Your friend, and the guy you bought it from? Don't listen to them! --No offence, but the carbs stick out like women's T*Ts and every man wants to **** with them.
They need to be the last thing you mess with!
The engine is an unknown to you--no history--so start from scratch and assume that everything that can be out of adjustment is.
Start with the basics. Do a compression test on all four cylinders. Then check for spark on all four. Put in new plugs (Champion L20V, 322, NGK BUH), Check to be certain that timing is set to 30 or 32 degrees advance at wide open throttle. Then, starting from the fuel tank, check the complete fuel system for clogs, leaks, and restrictions. Replace the fuel pump diaphragm and gasket. Replace the water pump impeller. Change the lower unit oil. Now, buy a manual and synchronize timing and carbs.
After doing this if you still have a problem, NOW it is time to mess with the carbs. First, using the manual, set the low speed needles--open 1 1/4 turns from lightly seated to start and adjust from there. Just be certain to not set them leaner than 3/4 turn out or you will melt pistons.
Now, if you have flooding problems, clean the carbs. A good disassembly and cleaning with WD40 will usually be good enough without rebuilding them.
PS. While on most engines changing carbs will not yeild more horsepower, That engine has small 1 5/16 venturi WB carbs. If you get the larger manifolds and TC carbs with 1 5/8 venturis, you can squeak out another 5-10 HP. If you are interested in larger carbs, send me a private message.
Parts can be found at the Chrysler Crew or
franzmarine@aol.com