2001 F9.9MSHZ 4 Stroke Problems (long read)

[richardjones26]

Ok here’s what I have done in the last year
1 - Brand new carb old one wouldn’t work no matter how many times I cleaned it
2 – New gas tank, line and bulb
3 – New Impeller
4 – New Plugs
5 – New fuel pump diaphragm

So today I remove old Premium gas from tank and put in fresh premium then removed gas line from carb and pumped out all the old gas out the line via hand bulb, installed gas line back in place and primed carb. Tried to start nothing so removed drain screw found not gas in carb, pulled carb and cleaned gas now getting to bowl. Hooked up water line to water intake above prop primed the carb and proceeded to pull my guts out starting it finally a couch then another splutter then it ran. So let it idle in neutral for 2mins and then put in gear and slowly increased throttle till I was at full let it sit there at that position for 2 mins and down to idle. Walking away with a big smile letting it idle it cough and splutters and dies so back to pulling my guts out and it only gives little cough and splutters but won’t run. Personally I think this engine was designed by the son of Satan LOL. So apart from a full exorcism what else can I do?

[99yam40]

cough could be what is called a lean sneeze
clean carb with heated sonic bath to get all passages cleaned up and set to spec in manual

compression or leak down test to make sure cylinders are sealing is always a good thing to do 1st

[richardjones26]

Please remember I’m just a regular guy who does not have access to heated sonic bath and I do not have any gauges to test compression, I’m trying to repair myself as the local boat yard is $130 an hour.

[richardjones26]

Going to bypass fuel pump and use a gravity feed if it runs i guess im back to the pump again

[richardjones26]

UPDATE
Jury rigged a gravity feed bypassing fuel pump didnt do a thing so going to pull and clean carb again.

[richardjones26]

UPDATE #2
Figured out what went wrong kicking myself for being so stupid LOL, as in previous message I said new premium gas but what I forgot to do was flush the old stall gas out of lines and primer bulb. So this morning cleaned the carburetor and before hooking up gas line to it I primed the bulb for 10 min flushing all the stall gas into bucket (dirty brown gas) till it ran clear the primed more until I was satisfied. I then hooked line to carburetor and primed and 1st pull it fired up I’ve ran it at various speeds now for the last half hour with no problems. Thanks to all for your suggestions and help.

[rodbolt17]

I have said it before.
rebuild the fuel system at breakfast.

fill it with trash for lunch.

guess what is for supper ??