85 horse carb question

[patrickj]

I had a boat mechanic tell me on the johnson an rudes the only difference in the smaller 3 cyl and bigger ones is the carbs... and that if you put 90 carbs on a 70 you have a 90...does this apply for force's? i have an 85 and im wondering if i can do this to mine.

 

[Frank Acampora]

Re: 85 horse carb question

Be certain he doesn't work on any of your engines!

On Force and Chrysler engines, Not only carbs, but port timing and gear ratios are different. Put 90 horse carbs on a 70 or 75 engine and you will get-----70 or 75 horsepower. Unless you modify your 85 ports and change to a 2 to 1 lower unit, it will still give you 85 horsepower. Note that some later Force 85 engines did have a 2 to 1 lower, but porting was still more conservative.

Much the same goes for other brands. If you research this subject here and in the outboard non-repair forum, you will see it has been discussed many times with the same answer.

Your "mechanic" is full of hooey and doesn't really know what he is talking about!

 

[patrickj]

Re: 85 horse carb question

he isnt my boat mechanic just some guy i was talking to that said he was a boat mechanic, well what about these reeds i keep reading about supposedly they have dual stage reeds that give your motor all around better performance... idle, acceleration, fuel economy...do you know any good or bad about reeds?

 

[Frank Acampora]

Re: 85 horse carb question

There are several brands of aftermarket reeds and the first brand that comes to mind is Boyeson. They are "dual stage" plastic reeds. There is also a fiberglass reed made but I forget the name. I have seen Boyeson reeds on a couple of engines and I, personally, am not impressed with them. However, the guys over at The Chrysler Crew seem to like them a lot. They are supposed to be a little more responsive. Again, however, if you do buy some, don't expect dramatic increases in horsepower. The main advantage with the plastic and fiberglass reeds is that if oune breaks, it won't damage the engine the way a steel reed would.

 

[patrickj]

Re: 85 horse carb question

im really want something to smooth out my idle... i do alot of trolling with the motor using sonar to find catfish in deep water and it tends to cough alot when idleing for long periods... i think they call it carbon cough... sometimes after i troll around for 10-15 minutes it will sputter one good time and die...then i restart it and it will idle for another 10-15 minutes and i read that the reeds will improve that and supposedly they are pretty simple things to install

 

[Frank Acampora]

Re: 85 horse carb question

Before you go invesing money, check you engine's fuel/oil recirculating system. Its purpose is to improve idling and prevent stalling as you describe.

Basically it takes condensed unburned fuel and puddled oil and cycles them to the (perhaps in your case, depending upon year) intake manifold to be burned before they accumulate and choke the engine.

On older Force engines: On the control cable side of the engine there is a plate connecting all three crankcases. At the bottom of this plate is a hose running to the intake manifold. This plate contains a screen and reed valve for each cylinder. Screens frequently are clogged on older engines. You remove the plate and clean the screens. Note that this system only improves idle. If it is non-functional, the engine will still run well at speed.

later model Force engines use slightly different ways of recirculating so if your engine is a later model, you must investigate the system.

 

[patrickj]

Re: 85 horse carb question

mine is a 1987, i will checking those screens, i know which tube you are talking about it comes off the coil side of the motor and runs around to plate behind the carbs. ill give those a once over. thanks alot

 

[patrickj]

Re: 85 horse carb question

i think i found my problem... when im in forward gear the little hose that i assume is part of the system your refering to is pinched as soon as i put it in neutral or reverse that hose is in the clear... i am going to take it out one day this week and test.