Force 35 hp rough idle and low compression

[joe3]

I have an older 35 hp force outboard that has been running great until I spun a prop and since then it is hard to start, hard to keep running, and when I put it in gear will stall out. I checked the compression and have about 80 psi in both cylinders. I pulled the carb and cleaned out (was very clean to begin with), checked the spark by pulling the plugs and grounding the head against the motor body. Seems to be ok. I pulled out the fuel pump and took it apart and saw no holes in the rubber and the spring valves seem to fit tight. There is some gas that can exit the carb when cranking. The motor will eventually start if I increase the idle speed. The choke does not seem to work as it never closes. I pulled number one plug ran the piston to TDC and the timing mark lined up. Have not checked the timing but the motor does run sometimes now and when I get it into gear and move the throttle forward will sometimes take off and run without a flaw and seems to have pretty good power. I am running it on an 18 foot pontoon and seems to have pushed it along fairly well when running. What to do next is now a mystery. Please help and thanks

 

[jerryjerry05]

Re: Force 35 hp rough idle and low compression

Welcome!!!
Fill out the profile,location??
You might be close to someone who can help?
Year?Serial#s Pics?
Anything you add can help!!
80# is probably wrong.
The guage or the wrong procedures.
Remove both plugs and try again with a different guage.
The GOOD thing is both cylinders are at 80# if there was a big difference then you'd need to worry.
Set the air/fuel screw at 1 turn out for inital adjustment.
RPM's in gear about 775-800 In neutral about 1100-1200
The choke, spray some WD or any spray lube on the choke slide.
Turn the key and as you turn it, push in the key to activate the choke.
To work the choke,you MUST hold the key in while it's turning over.
Key not in=no choke and poor starting.
Check the gas for water,clean the plugs.
Post the results of the new comp test.

 

[joe3]

Re: Force 35 hp rough idle and low compression

Thanks for the help. I don't know exactly the year of the motor but here is some stats about it:
1. Force 35 hp, 2 cylinder, serial number tag has been removed. Not sure why when I bought it was this way.
2. Checked the compression with a brand new gauge with WOT and both cylinders about 80.
3. Fuel mixture screw is turned out from seated position about 1 to 1 1/2 turns. When it does start I have adjusted this screw to the middle position between rough idle in and rough idle out which ends up being around 1 1/4 turns out.
4. Key in and choke closes but after that if starts then opens full open and does not move.
5. plugs look dark to black and if it does not start then wet. Plugs are new. Gets good spark when pulled and grounded to chassis. Have checked spark with spark checker but looks pretty good with the test I did. Seems like it should ignite the gas if there is any gas in the chamber.
6. Bulb squeezes up and can hear and feel the gas pumping up in line.
7. Gas filter screen is clean and was never dirty as was the carb bowl and jets.
8. Changed out brushes on starter and turns over quickly.

How do you check if there is water in the gas? I just filled it with premium gas so seems like should be ok but not sure.
As your posts says if the motor does not start in a few seconds then something is wrong. Mine will eventually start but it seems right on the edge of starting can hear it and see it coughing and will sometimes start if I manually open the throttle plate inside the carb. I thought I had it the last time it started because I was able to adjust the fuel mixture screw and the idle to about the 1000 rpm in neutral. It runs rough though and when shifting into gear can stall out. Seems to be backfiring or coughing not sure which. I have been trying to upload some pics but the upload manager must be messed up because it just sits there with the flying kite going around in circles with nothing happening after minutes ( the file is very small 700Kb). Not sure what is going on with the upload manager.
Hope some of this info helps.

 

[joe3]

Re: Force 35 hp rough idle and low compression

Sorry was supposed to say "did NOT test the spark with a spark tester"
Also to minimize the problem and get to the basic issue.

The motor is hard to start and when it does start it will stall when going into gear unless I push the throttle control just right to get it going quickly. When up and running in the water runs perfect.
Thanks again.

 

[joe3]

Re: Force 35 hp rough idle and low compression

Update: removed the carb again (which is easy) to check if getting gas and to flush out again. There was nothing obstructing any holes as I blew it out with carb cleaner. Took out the fuel mixture screw and blew that out and every other hole. Readjusted the float setting to be slightly below level to see if that kept some of the extra gas out of the throat when cranking.
Put back together and now it does not even fire. Compressed the bulb multiple times and even took the carb off again to make sure there was gas in the float bowl. It was full of gas. Not sure what happened but won't even fire now. Turns over like crazy.