45hp Honda dies when throttling down

[onagas]

45hp Honda dies when throttling down

My engine dies on me whenever I throttle down. It idles like it is running on only one or two cylinders. When I throttle up rapidly it to a high rpm it runs okay but the minute I slow down it dies. When its running okay at a higher rpm and I throttle down rapidly to idle it doesnt die. I overhauled the carburetors and changed the head gasket but it still does the same thing. Someone told me I need a valve job. I'm skeptical about this because it runs smoothly at a higher rpm.Would appreciate some ideas on whats the problem.

 

[Bear]

Re: 45hp Honda dies when throttling down

Re: 45hp Honda dies when throttling down

Lack of fuel due to an airleak somewhere between gastank and fuelpump or carbs, I think (actually I don't know, this is a long "take me to the top"). <br />What happens if you squeeze the bulb at (rough)idle? Is the bulb soft at this time?<br />I think the accelerator pump makes it rev past this weak spot and then get enough fuel, even if there is a air leak somewhere. Are you shure the carb gaskets are tight? No air leaks there?<br />Water in gas tank, carb bowls and fuel filter? Drain the carbs in a clear glass bottle and see what you find. Do you have fresh fuel?<br /><br />When did this start?<br /><br />"All there questions and no answers"<br /><br />/Bear<br /><br />Honda 45 1991-1997 Honda 50 1998-. Never had a problem what so ever.

 

[hondon]

Re: 45hp Honda dies when throttling down

Re: 45hp Honda dies when throttling down

Sounds like you may well be experiencing a faulty check valve between your accelerator pump dashpot and the carbs.I would certainly get this engine to square one to troubleshoot this further. Adjust the valves. Do a leakdown test ,and sync the carbs. Take a fuel sample to check for contamination.If you are not using one ,add a water separating fuel filter.

 

[onagas]

Re: 45hp Honda dies when throttling down

Re: 45hp Honda dies when throttling down

Thanks guys for all the ideas. Will try to check everything you suggested. I have twin engines with two separate tanks so I know its not the gas. I believe its something between the gas tank and the carbs.Also try to switch manifolds on the engines and see what happens.

 

[onagas]

Re: 45hp Honda dies when throttling down

Re: 45hp Honda dies when throttling down

Also I noticed that when I tried to tune the carburetors the second carb doesnt respond when I turn the screw.

 

[enn]

Re: 45hp Honda dies when throttling down

Re: 45hp Honda dies when throttling down

Your carbs need balancing - you need special tool to do this - the bad syncronisation of the carbs will give all the symptoms you mention.<br /><br />