I own a 18984 Bayliner Capri with an 85 hp Force outboard. I purchased this boat approx. six years ago. About 4 years ago I completely rebuilt the power head with the exception of going through the fuel system. The #2 cylinder went south. I only put about 2 hours of run time on it after rebuild and have recently started getting the boat prepared for the water again after sitting for almost 4 years. I decided to go through the fuel system just to make sure everything was up to par before setting it back in the water. The last thing I want is to burn up the fresh power head.
I have been turning wrenches for years on automotive and motorcycles and if anyone rebuilds engines knows that an engine is an engine and that they all function the same with minor differances in the systems which operate them.
With that said, upon diving into the fuel system on my 85 hp, I have noticed some small but possible problems with the system that could have alot to do with these engines having some runability issues. Especially in the lower rpm ranges. From what I have experienced, this particular engine is hell on fuel in the lower rpm's and is not that throttle responsive in comparison to most 2 stroke engines that are mounted horizontally as apposed to vertically.
I relate alot of this problem primarily on the fuel recirculation system. The fuel puddles at the back and bottom of the cylinders at low rpm's because the engine is mounted vertically. The current recirculation system re-intiates this fuel back into the intake manifold behind the carburetors. This is un-metered fuel which in turn can still give you a rich mixture at low rpm's even if you adjust the carburetor's fuel mixture. The carburetors fuel mixture screw only works for the idle circuit, not when you are just of idle puttering along.
I also noticed that the carburetors really are not seperated. They are connected with passages in the intake manifold itself. If one carburetor for one particular cylinder is slightly lean, you would never really know it because the one below it could make up the difference for it. Has anyone else noticed these possible design flaws? I am currently initiating some changes in the system to try to cure these runability issues.
I have been turning wrenches for years on automotive and motorcycles and if anyone rebuilds engines knows that an engine is an engine and that they all function the same with minor differances in the systems which operate them.
With that said, upon diving into the fuel system on my 85 hp, I have noticed some small but possible problems with the system that could have alot to do with these engines having some runability issues. Especially in the lower rpm ranges. From what I have experienced, this particular engine is hell on fuel in the lower rpm's and is not that throttle responsive in comparison to most 2 stroke engines that are mounted horizontally as apposed to vertically.
I relate alot of this problem primarily on the fuel recirculation system. The fuel puddles at the back and bottom of the cylinders at low rpm's because the engine is mounted vertically. The current recirculation system re-intiates this fuel back into the intake manifold behind the carburetors. This is un-metered fuel which in turn can still give you a rich mixture at low rpm's even if you adjust the carburetor's fuel mixture. The carburetors fuel mixture screw only works for the idle circuit, not when you are just of idle puttering along.
I also noticed that the carburetors really are not seperated. They are connected with passages in the intake manifold itself. If one carburetor for one particular cylinder is slightly lean, you would never really know it because the one below it could make up the difference for it. Has anyone else noticed these possible design flaws? I am currently initiating some changes in the system to try to cure these runability issues.