help with my boat

[sailboat man]

i boght a 1986 hunter 31 4 month ago and every time i crank my 18 hp yanmar it is stuck wide open how can i fix this promble to get it back to normal

[jrd22]

Hi, a little more info. is needed. Do you mean that when the engine fires the throttle is stuck wide open so the engine goes to full RPM? Is the throttle cable attached to the injection pump and does it move when you move the lever? Did this just start happening or has it always been this way since you bought the boat?

[stevensc]

Try this first, give all the cables and linkages from the handle to the carburetor with Kroil or some other kind of penetrant/lubricant give them a good work out opening and closing. Maybe something is sticking and this could loosen it up. in any case it won't hurt anything.
Good luck
Steve

[sailboat man]

Originally Posted by jrd22

Hi, a little more info. is needed. Do you mean that when the engine fires the throttle is stuck wide open so the engine goes to full RPM? Is the throttle cable attached to the injection pump and does it move when you move the lever? Did this just start happening or has it always been this way since you bought the boat?

yes the throttle lever moves back and forward but does nont trun down the rpm some body said the injection pump got trash in it

[sailboat man]

is there a manuel to take the injection pump out so i can clean it

[sailboat man]

Originally Posted by sailboat man

i boght a 1986 hunter 31 4 month ago and every time i crank my 18 hp yanmar it is stuck wide open how can i fix this promble to get it back to normal

it just happen

[jrd22]

An injection pump isn't something you can disassemble yourself (ordinarily). I would call your Yanmar dealer and get the manual. You might be able to remove the pump yourself if you have the tools and knowhow. If the cable and throttle arm are moving at the injection pump then unfotunately it might be something in the inj. pump that has come loose.
Good luck, John

[Boracay]

Try having a look at where the throttle cable connects to the injector pump.

Have a mate move the throttle control in the cockpit (make sure the engine is securely off, and the boat is properly moored).

Check that the cable sheath is properly attached to it's mounts both on(?) the engine and at the cockpit.

Look at how the cable connects to and moves the lever on the injector pump.

It should move smoothly with no binding.

Now check that the return spring on the injector pump has not broken.

If all looks OK disconnect the cable from the fuel pump throttle lever. Make sure none of the small parts fall into the bilge.

Now get your mate to move the throttle control again and see how smoothly it moves.

Move the throttle control on the fuel pump and check that it returns to the neutral position when released.

If all looks good reassemble and carefully retest.

This is the limit of my suggestions.

Unless, of course, some bright spark has reversed the gearbox and throttle controls.