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Still having problems with my boat motor not running after the fuel filter empties

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I can pump the bubble I have replaced everything but I can pump the bubble and fill up the filter in the motor and that we're talking about a 25 horse Mercury two-stroke 1999 model EH electric start telehandler my first one ever two-stroke to fool with but to check the motor to see if I'm getting suction to the carburetor there are two lines coming from the head both one from each cylinder they come around to the reed block and go into it under the carburetor and by the diagram it says there a check valve on the end of them I'm thinking that's where it gets its pulse how do I go about checking these valves and see if I got suction I was wondering could I get a pressure checker that goes into spark plug hole Will it show me a little vacuum there or can I just turn it over see if it pulled I don't know what's the best way to check this without taking it all the way apart and which it's already drove me back to smoking but it's driving me crazy I wake up 3:00 in the morning thinking about how I can fix this and go fishing it has done broke me and I need some suggestions please anything how to check or how to rig up something to check vacuum from the motor because when I pull the carburetor back off to double check it I want to be able to check the vacuum from the motor to make sure I'm not just wasting my time and money before I go in to it too deep probably already am
 
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One thing about it though I'm going to get it if I had to break it all the way down put gaskets in bearings in the hole motor I'm going to get it it will not whoop me at least it not without one more big three-letter word of a fight!!!!!!!!
 

azsunfun

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I can pump the bubble I have replaced everything but I can pump the bubble and fill up the filter in the motor and that we're talking about a 25 horse Mercury two-stroke 1999 model EH electric start telehandler my first one ever two-stroke to fool with but to check the motor to see if I'm getting suction to the carburetor there are two lines coming from the head both one from each cylinder they come around to the reed block and go into it under the carburetor and by the diagram it says there a check valve on the end of them I'm thinking that's where it gets its pulse how do I go about checking these valves and see if I got suction I was wondering could I get a pressure checker that goes into spark plug hole Will it show me a little vacuum there or can I just turn it over see if it pulled I don't know what's the best way to check this without taking it all the way apart and which it's already drove me back to smoking but it's driving me crazy I wake up 3:00 in the morning thinking about how I can fix this and go fishing it has done broke me and I need some suggestions please anything how to check or how to rig up something to check vacuum from the motor because when I pull the carburetor back off to double check it I want to be able to check the vacuum from the motor to make sure I'm not just wasting my time and money before I go in to it too deep probably already am
you will get pressure from spark plug area not suction, are you sure of your fuel to oil ratio mixture, is there crap in the tank blocking flow, is your tank vented, if you look in intake and can see your reads take a look for sludge balls keeping reads open, and are you sure your not actualy flooding the motor, mercs dont like flooding.
 

Ziggy

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More than once have I had the checkvalve in the squeezeball fail and starve the motor.
Check the easy stuff first.
Has the motor been sitting around a while? 2stroke fuel loves gumming up carbs, venturis and such. Fuelpump diaphram?
 

Outdrive1

Outdrive1 Marine Sales https://www.outdrive1.com/
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Couple things on little motors. I’ve owned a few on mini Schiadas. One, the clear plastic filter on the motor needs to be leak free and tight, or the pump cannot pull gas up to it. Check the o-ring. Make sure it’s super tight.

Second. Change the diaphragm in the pump. It’s cheap. And easy. And they need to be fresh.

Last. Those pumps have a tough time pulling a long distance or through a water separator or external filter. Make sure it has an easy or short path, if not add a small electric pump in the boat to help it.


My two cents. Good luck.
 

HST4ME

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Pull the reed block off and look at the reeds, make sure none are standing open. There is a rubber strip that divides the crankcase halves that stretches around the reed block that should be replaced. The fuel supply line from the tank should be no bigger than 5/16 and ideally it should be 1/4 inch. Small motor fuel pumps do not draw enough vacuum to pull the volume of fuel through a 3/8 hose correctly.
 
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When I pulled the carburetor back off after replacing everything from the tank to the motor and I had done rebuilt the carburetor but I put the same gasket back on it came off of the intake and carburetor when I got the checking I pulled it back off and I was falling to vacuum how it sucks cuz I didn't know when a two-stroke this is my first one when I got around to where it sucks through the head through the tubes and the reed block up through that little hole in the carburetor somebody had put the wrong gasket on it about 10 years ago they rebuilt the carburetor and this is a 99-25EH 2-stroke Mercury it's been sitting 8 years or 10 I don't know but the only thing wrong with it after I replaced all the hoses and got the leaks fixed they had the hole covered up with the wrong gasket I went back in my kit found the other gasket compared it in it lined up with everything and I checked to make sure that I put the right one that came off of it that I took off of it on it so I didn't make the mistake it was made before I got it they did that and that's why they sold it off the motor was bad head gasket or something probably they thought the bearing or something was bad the way it was shaking but it runs like a little brand new Honda four-stroke four-wheeler now it runs so good I could not believe it when I put it back together it's like I thought it was running before but it was just hitting on one cylinder I guess because the bottom plug was soaked but when I got it fixed and cleaned in plugs Man I really appreciate all y'all's hair cuz y'all really help me think this thing through and I found a problem and it really made me feel good about myself when I found it and I'm sorry I have to use text to talk and can't punctuate everything with that I just can't see good enough That's one thing that makes it hard to work on motors carburetors especially have to have magnifying glass but I got it thanks to y'all's help All y'all's input everybody y'all have taught me how the two-stroke motor operates we do vacuum on the tank pressure on the tank and way it sucks up through the check valves I have learned a lot I want to thank everybody that had some input because you really helped me and saved me a lot of money if I would have took it to a dealer it would have cost me a lot of money thanks again everybody
 
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