115 hp cranking problem

[j. glenn]

1989 115 hp Yamaha has a problem with not cranking. Will spin over but will not crank, no fire on plugs. Only happens on water. I Have experienced the problem on last 5 times out. By the time I get it to shop it cranks and runs fine. Have had it checked out by 4 mechanics with no problem cranking in their shop. Cranked off trailer today, ran 1 mile, fished 20 minutes and would not crank. This is a repeat of last 5 trips. Loaded on trailer, drove 20 miles home and it cranks fine. Need help on this. Something is changing value. Would a kill switch, or ignition switch be the problem. have checked most connections.
Condition resets between water and shop.

jack glenn

[TownsendsFJR1300]

I would ask the mechainics run it either on muffs or in a tank of water for at least 20 minutes (or the time it takes to act up). It may be as simple as a bad ground that's acts up once warmed up and bouncing around, or ?

Obviously plugging it into a computer may show something too(if its available).

I'd look real hard at all the grounds (literally un-bolt them, clean, di-lectric grease, and re-install) especially around the coils, anything ignition related.

**The only real obvious change is that the engine gets hot and then doesn't start. Once it cools down, it starts...

[boscoe99]

Just as a point of reference for future conversations, cranking is the motor being rotated by the starter motor. Or, a pull cord. Starting is when the motor fires up. Running is when it starts and then continues to run.

Cranking comes first. Starting comes second. Running comes third. So, there can be a condition where it does not crank. There can be a condition where it cranks and fires but then dies. Finally and hopefully, it will crank, start and run.

Years ago before your time, a motor was started with a hand crank. The crank was installed into the motor, held with one hand and then rotated (cranked) with the other hand. If a motor tried to start in reverse during the cranking procedure the crank could quickly rotate backwards and break an arm. This is where the term cranking came from.

[TownsendsFJR1300]

Just as a point of reference for future conversations, cranking is the motor being rotated by the starter motor. Or, a pull cord. Starting is when the motor fires up. Running is when it starts and then continues to run.

Cranking comes first. Starting comes second. Running comes third. So, there can be a condition where it does not crank. There can be a condition where it cranks and fires but then dies. Finally and hopefully, it will crank, start and run.

Years ago before your time, a motor was started with a hand crank. The crank was installed into the motor, held with one hand and then rotated (cranked) with the other hand. If a motor tried to start in reverse during the cranking procedure the crank could quickly rotate backwards and break an arm. This is where the term cranking came from.

Your going to be posting that a bunch of times, but very accurate.

[99yam40]

you will have to test for spark when the problem is there to make sure if you are chasing an electrical or fuel problem

[j. glenn]

Thanks for the posts about my starting problems. Have cleaned all grounds to case and block. Checked all wire connections to electrical boxes. Ran on muffs for 20 minutes, used kill switch, engaged shifter and varied RPM’s. Shut down and waited 20 + minutes. (looking for residual heat). Motor cranked and ran on first revolution. Still looking at ECM and ignition switch as possible problem. Motor has never missed when underway only after stopping to fish. I am getting good on loading with *****ing motor. J glenn

[j. glenn]

89 yamaha 115 not starting

Thanks for the posts about my starting problems. Have cleaned all grounds to case and block. Checked all wire connections to electrical boxes. Ran on muffs for 20 minutes, used kill switch, engaged shifter and varied RPM’s. Shut down and waited 20 + minutes. (looking for residual heat). Motor cranked and ran on first revolution. Still looking at ECM and ignition switch as possible problem. Motor has never missed when underway only after stopping to fish. I am getting good on loading with *****ing motor. J glenn

[ausnoelm]

be pretty much a miracle if it is the ECM or the ignition switch for that matter, but not impossible of course. OH and thank you Boscoe for the cranking/starting/running thing, it helps is we all know exactly what the question relates to, rather than need to ask for explanations.

[j. glenn]

115 yamaha 89 starting problem

On the water today and had no problems, Ran for 2+ miles, shut down and restarted after 20 minutes, did this several times and had no problems with motor. Was nice to load on trailer using big motor. Thanks to TownsendsFJR1300, boscoe99, ausnoelm and 99yam40 for postings and advice. Not sure if all is well but sure felt good leaving the water. J. glenn

[TownsendsFJR1300]

Excellent!

Please re-post after several outings how its doing...