Lucky, Is there another set of numbers following the4011-17? The two sets of numbers you have listed here are the model and type. There should be another set following the type and that will be the code. The first two numbers of the code will be the year that your motor was manufactured. See if you can find that third set of numbers. Ogy
So is it a rare engine? What are the years of your engines. I looked up the model number on briggs website and it says its a 4hp and gave me a whole lot of info just not the year. Thank you so much for your help. If you got any recommendations about what to do do my engine please tell me. I will paint mine white btw.
Oh Lucky, I have a hundred recommendations and about a hundred questions. To start; I'm going to assume that you are just looking to get your motor running and use it in a minibike. If you can answer a few questions for me it will give me an idea of which direction would be best for your purposes. Is this your first small motor? Are you familiar with how these motors operate? Have you ever taken one apart before? Does this motor start and run right now? The answers to these questions will allow me and others on this site (who know a lot more than I do about motors) to give you all the help you need. You asked if these motors are rare. While 3hp and 5hp Briggs are everywhere, the 4hp are plentiful but just less common. Let us hear from you. Ogy
So I got it running. Really good spark. Tore apart carb, cleaned, and reassembled. The gasket is leaking a bit between the tank and carb. Flushed the tank because there was stuff in it. Took the head off. Oil has been sitting on the piston so it was very well lubricated and almost no carbon build up. I am not a mechanic but I LOVE motors. Worked on lots of small engines. So I have never completely disassembled a horizontal like this but I know how it works and could probably do it. I have worker with lots of these including 2 and 4 strokes. I want to tear it down and do a full rebuild on the engine. BTW a small bit of the cooling fin on the head is broken. And if I could find a cheap minibike frame or maybe even build one i would love to use this engine in it.
Lucky, Because you're looking for a reliable motor to install and run on a minibike; I'd do the following; Check for compression by pulling on the recoil starter handle very slowly. There should be a lot of resistance if the compression is good. Start the motor. Does it stay running. Does it run smoothly or does it gallop or run a short time and quit. Is the exhaust black and smokey or relatively clear. If the motor runs and continues to run without black exhaust then the internal components of your motor are still in pretty good shape. I'd remove the recoil housing and clean the flywheel magnets with some very fine 1000 grit emory paper. Clean and degrease the fins and all the rest of the motor. Don't mess with the points and condenser. If it's running then the ignition is ok. After everything is degreased I'd remove the cylinder head, clean the carbon from the head and valves, install a new head gasket, and torque the headbolts to 110 to 120 inch pounds. Take a hundred pictures of the carb linkage and the governor linkage (especially on the 5hp) and save them. Remove the carb from the motor and then remove the tank from the carb. Thoroughly clean the tank so it's shiny inside. Your carb will probably be a pulsa jet type. Remove the four screws of the side cover and you will see a rubber diaphram covering a spring. Remove the spring and it's cap and give the carb a good cleaning. If they are in good shape you can reuse the spring and cap but do not reuse the diaphram. They're cheap. Replace it. Reattach the carb to the tank using new gaskets and reattach the carb-tank assembly to the motor using a new gasket. Some of the 5hp motors used two gaskets. Any painting should have been done while the motor was disassembled. Put new decals on if you desire and you should be good to go. I should have mentioned to examine the starter rope. If it's at all worn; now is the time to replace it. Give a shout if you run into any problems. Ogy
That motor has insane compression. I can't start it while it is on the ground. I have to bolt it down to something. I already did most of the stuff you said. The motor runs very well. Stays idling fine and when you open throttle it runs good. There is a little bit of grey smoke. Not a lot and definitely not black but there is a small bit. I already cleaned the flywheel magnets and coil but the flywheel does have some surface rust on it. I took the head off when I got it. The Cylinder had oil sitting on it. So it was well lubricated and it took a lot of the carbon of the piston. I did give the valves a bit of a clean by scraping them off but how else should I clean it? The head gasket was in really good condition. My torque wrench is broken right now but I will have it fixed soon. When I took the head off it was just loose sitting there. So I reused it. I did all the steps you talk about in cleaning the carb. I didn't have new gaskets at the time so I just reused the old ones. I did flush the tank but how do I clean the inside? Also I think my carb is missing part of the linkage? Do you have any idea where I could get the parts I need? I just made a thread about my motors and took a lot of pics. By comparing them I see that both are missing parts. And is the engine 4 or 5hp? Also after I have started the motor the recoil is loose and then it snaps back every few seconds? What could cause that? Thanks for all the help.:thumbsup: