2004 Honda 9.9hp four stroke will not start not even a spudder

[fishon71]

I have a 2004 Honda 9.9hp four stroke that will not start. It has spark on both cylinders, I have cleaned the carb and it has good compression (at least it feels that way) I can't even get a spudder even with starting fluid, I don't know where else to turn as it has all the basics to run - any tips to try?

 

[Sea Rider]

Lately some boaters are experiencing exact same issues. So you have spark on both cylinders. On a dark room, garage, remove cowl and pull rope several times assuming it's a non electric start engine. With plugs attached, check if plug caps or even plug cables divert electricitty to ground. If so, the plugs won't have enough punch to ignite fuel in combustion chambers. Other issue,spark could be poor, will need a spark tester to check that.

Happy Boating

 

[vcaptain]

Have you checked the valve clearance? Are the plugs wet when you pull them? A compression check will tell you alot, $50 at sears for a kit.

 

[fishon71]

Plugs are a little wet but not flooded
I have a compression tester but do not have the socket for the small spark plug.
Where can I find the valve adjustment procedure

 

[fishon71]

Lately some boaters are experiencing exact same issues. So you have spark on both cylinders. On a dark room, garage, remove cowl and pull rope several times assuming it's a non electric start engine. With plugs attached, check if plug caps or even plug cables divert electricitty to ground. If so, the plugs won't have enough punch to ignite fuel in combustion chambers. Other issue,spark could be poor, will need a spark tester to check that.

Happy Boating

Last night in the dark checked for spark leakage even wet all the wires - no leakage seen and spark at plugs looks strong.

 

[fishon71]

Have you checked the valve clearance? Are the plugs wet when you pull them? A compression check will tell you alot, $50 at sears for a kit.

I orders compression tester adapters for the small plugs, will test and update one I know the compression.

 

[fishon71]

Okay got my adapter today and jumped right on this. I have 125 psi on the top and 100 psi on the bottom. Now I know that is way off but it still should run but maybe rough. Also the top ran right up to 125 psi quickly with 4-5 pulls the bottom took a ton of pulls, maybe 10-12 to get to 100 psi. They both held and did not bleed off - what do you think?

 

[Sea Rider]

Don't know about Honda, on other engine brands, there should be a max of 15 PSI diffrence between both cylinders. If more could be due to piston damage, stuck or broken piston rings, scored cylinder wall, bad head gasket, Sorry, don't have experience with valves and their particular issues or 4 stroke engines.

Happy Boating

 

[vcaptain]

I'm no expert, but in my experience it should take the same amount of pulls on each cylinder to get compression, no more than 3 or 4.. You had both plugs out for the test? I'd pour some seafoam in the cylinders and let it sit, then turn it over, then check compression again. If ti's still off check the valve clearance as one or more may be stuck.