2002 150hp 2 stroke

[Towboat1]

I could sure use some advice! I have 2002 150hp Yam carbureted outboard, runs great, Idles fine . After I run the engine for a while if I shut it off it has a hard time starting back up , turns over just won’t start. I can smell fuel so I think it’s getting fuel , after it does start sometimes 15 minutes later it runs fine . Can anyone tell me where to start checking for the problem ?
Thanks in advance, Mike

[jimbliss]

Start with a compression test. Low compression causes warm motors to be hard to start. All cylinders should be with end of 10psi of each other.
Good luck.

[99yam40]

make sure you run motor at idle for a few minuets after a hard run to help cool off motor to see if that helps any.

Owners manual should say that

[jb123]

Have you tried repriming ball at restart ?
Changed checked fuel pumps ?

[Towboat1]

I just bought the engine , and did a compression check then! Right three cyl. were 98psi left three were 103psi. Is that strange to have all three on each side be the same ? What advice would you give? run the engine for 5 minutes or so at idle after running at 4500 for 15 or more minutes ? Boat had 80 gals of one year old fuel in the tank that I had pumped out and the carbs rebuilt at the same time, so I'm hoping its not fuel related .

Thanks,

[Towboat1]

jb123 we did try pumping the ball pressure up , but no I haven't done anything to the fuel pump. I think I'll replace the ball and hose this week to eliminate that possibility.

Thanks

[Towboat1]

Problem has gotten worst now engine misses when running at speed after its run for a while . Is there anyway to test the fuel pumps ?

[TownsendsFJR1300]

Try draining the float bowls on all the carbs. A tuna fish can usually fits well to catch what comes out.

Please pay attention to any crap coming out and also for any water in the carbs. If you find any, prime the fuel valve some more and pump out until all the water, etc is clear..

Have you checked (emptied, cleaned) the Yamaha, under cowl fuel filter, again, (checking for crap / water)?

[Towboat1]

I just purchased the engine and had the fuel tank drained and purged , the carbs rebuilt , new plugs , change all filters ! Engine runs great until it gets hot ! then misses and won't restart until it's sat for awhile

Thanks

[jimbliss]

Take a look at the plugs.
Make sure they are the correct NGK plugs and gaped wright.
You could also have a gas tank vent problem.