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doughboy65

A 6hp model isn't going to have a great amount of compression but is normally in the 70 psi or greater range. It really depend on how fast one can pull the manual starter cord.... HINT... a rope around the flywheel will spin the engine over faster.

Why didn't you list the compression that you are currently getting? We would be interested in knowing your starting point.
 
Thank you for the info ! Right now I am getting just above 30psi in both cylinders. I can get it to fire a couple of times as I crank and prime it. I am afraid the compression is too low to draw fuel .
 
Fairly common for the head gasket to blow between the cylinders.------You must take the head off before going any further.
 
I have the head off now but I do not see any evidence that the gasket is blown. A lot of carbon build up though. The pistons seem tight in the cylinders and no cracks
 
Thanks to all who are helping me out. If I am getting any measure of compression it should draw fuel huh? Maybe it's a carb. problem. The motor had set up for several years. I put a kit in it, new points and condenser, and a water pump kit. Should be almost like new! Any way thanks for the help so far !!
 
I got the parts today. head gasket ,fuel pump ,and thermostat. Compression is much better around 70. Been pulling on that crank rope for a couple of hours now! Still can't get it to crank. Spark is good. No matter how I adj.the fuel it does not kick off. Acts like it is not getting fuel to cyl. Carb bowl is full. I've been priming and I get it to spudder.
 
70 psi compression is okay, and if you have spark that will jump 1/4" on both cylinders, that leave the fuel system.

In all probability the carburetor is fouled somewhat. Remove, clean, and rebuild it as needed. Be sure to manually clean the horizontal brass high speed jet that's located in the center bottom portion of the float chamber as fuel must flow thru that jet before it can gain access to any other fuel passage.

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 
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