yamaha 2 stroke 175 hp

[rocket ron]

this motor wont start when its hot, it cranks over fine , im not sure if its lack of spark or if it is fuel

[99yam40]

We can not tell from this side of the computer screen, you will have to test things to see

[rocket ron]

thanks , but i was hoping that some one might have encountered the same problem that could point me in the right direction

[halfmoa]

Great info here http://forums.iboats.com/engine-frequently-asked-questions-faq/general-engine-checks-joe-reeves-188767.html

and here http://forums.iboats.com/engine-frequently-asked-questions-faq/outboard-wont-start-158071.html

and here http://forums.iboats.com/engine-frequently-asked-questions-faq/how-testing-your-boats-fuel-system-283363.html

If you can narrow down your problem further using the diagnostic tests in the above posts and post any questionable results you'll have better luck getting an answer. Some of us can be a little harsh.

[robert graham]

Usually they have a bit more trouble starting when they're cold, generally start instantly when motor is warmed up. Maybe try pumping the primer bulb a few times when motor is hot and give that a try. Are your spark plugs good and clean? Good Luck and let us know what you find!

[99yam40]

thanks , but i was hoping that some one might have encountered the same problem that could point me in the right direction

Sorry if that sounded harsh, I missed the part about when hot, but you still need to check to see if it is sparking or not.

A inductive timing light or a spark tester works well to see that each plug wire is getting spark.

Also give more info on the motor like model # and what is happening and when

[rocket ron]

thanks im putting the motor in with marineland today,the spark plugs look new, i should know by the end of the day what is faulty

[rocket ron]

ok i got the engine back from the shop & they did a service ,change plugs & oils ,the usual, they tell me the plugs where oily & the fuel mixture was a bit rich,which they tuned it better, but they couldnt find a fault, i guess i will find out this weekend.

[99yam40]

If this thing runs fine but has trouble starting after getting warmed up then you or the shop will have to do some testing in those conditions, while the problem is occurring.

Since you will not post a model # no one even knows if this thing has carbs, or injectors

[rocket ron]

oh model number is UL 500232 X 6G5 1996 yr