Hot starting troubles

[Yamacat17]

I have a 16 zr7000 limited with 7500km (4600miles) that recently is having issues when starting hot. It's got the most recent flash and has started relatively well with new flash until recently. It seems to "stumble" immediately when cranked then will not fire, can take 2 or more tries until it cranks over 2 or 3 times then fires normally. It has never failed to start but seems to not be firing up as usual lately. Once running it's running better than ever but the starts are starting to get embarrassing..not sure where to even start looking, any help or insight is appreciated.

 

[maim]

have you done the plugs yet?

 

[Yamacat17]

I have not, pretty low mileage to replace plugs. But I guess it's the first place to start for sure..

 

[Confused]

I have not, pretty low mileage to replace plugs. But I guess it's the first place to start for sure..

I replace plugs every year, it's cheap. They foul fairly easily, especially if you start it and not let it warm completely up.

 

[grizztracks]

Sounds like possibly a bad starter. Mine started doing the same last season. I replaced the battery at the start of this season but it continues to struggle at times so I order a new starter and will be swapping it out tomorrow. These starters are known to have problems with the magnets slipping or breaking causing them to be less efficient at cranking over the engine. Also, if the magnets come loose and lock up the starter they can cause internal motor damage.

 

[Yamacat17]

Sounds like possibly a bad starter. Mine started doing the same last season. I replaced the battery at the start of this season but it continues to struggle at times so I order a new starter and will be swapping it out tomorrow. These starters are known to have problems with the magnets slipping or breaking causing them to be less efficient at cranking over the engine. Also, if the magnets come loose and lock up the starter they can cause internal motor damage.

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Let me know how that works out for you. I have a brand new battery this year so that rules out power issues. I do feel that when it "stumbles" initially it's not cranking at full speed possibly. There's definitely a big difference when it cranks 3-4 times then fires like it should.

 

[grizztracks]

Let me know how that works out for you. I have a brand new battery this year so that rules out power issues. I do feel that when it "stumbles" initially it's not cranking at full speed possibly. There's definitely a big difference when it cranks 3-4 times then fires like it should.

Mines intermittent and some times when I attempt a hot restart it won't crank at all. You'd think the battery was dead but after a few attempts it would suddenly take off. I've done a lot of these starter swaps and always pull the old starter apart to see what's going on inside. I don't think I've ever seen one yet that didn't have a cracked magnet.

 

[grizztracks]

Swapped out my 2015 Viper starter tonight. Very easy 30 min job and the new starter definitly is rolling the engine much faster. After the replacement I separated the original OEM starter and was surprised that the magnets were still intact. The issue ended up being worn out starter brushes. I'll probably replace them and keep the starter as a spare.

 

[Yamacat17]

Swapped out my 2015 Viper starter tonight. Very easy 30 min job and the new starter definitly is rolling the engine much faster. After the replacement I separated the original OEM starter and was surprised that the magnets were still intact. The issue ended up being worn out starter brushes. I'll probably replace them and keep the starter as a spare.

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Great job! The pics are a nice touch. Once the two bolts are out does the starter just pull back to remove? Did you go with the OEM replacement?

 

[grizztracks]

Yes, once the bolts are out it slides back. There's an o-ring that seals the nose cone of the starter to the engine block so there will be a little resistance pulling it out.

I've replaced many starters over the years in Yamaha engines and other powersports engines. I typically don't replace them with OEM starters due to cost and the fact they don't seem to last. I usually buy starters from DB Electrical and have had good luck with them but the Yamaha 3 cylinder starter is currently out of stock at DB so I ended up ordering from Rare Electrical which I've also purchased from in the past and so far haven't had any problems.

 

[srvfan]

Mine starts lousy hot after I got the latest flash starter spin fine. It will let out god awful back fires if I crack the throttle just slightly that seems to help. If I just crank it , it will pop a couple times sputter and die. Wait 30 seconds crank it and kaboom it will blow your ear drums out. Utterly dissatisfied with how this sled starts/runs compared to a Vector . Cold starts are better after flash

 

[Yamacat17]

Yes, once the bolts are out it slides back. There's an o-ring that seals the nose cone of the starter to the engine block so there will be a little resistance pulling it out.

I've replaced many starters over the years in Yamaha engines and other powersports engines. I typically don't replace them with OEM starters due to cost and the fact they don't seem to last. I usually buy starters from DB Electrical and have had good luck with them but the Yamaha 3 cylinder starter is currently out of stock at DB so I ended up ordering from Rare Electrical which I've also purchased from in the past and so far haven't had any problems.

I replaced the starter today, what a difference in cranking speed then before. I pulled apart old starter and can't see anything broken or out if place (magnets all good). The brushes are definitely worn but all still there and intact? The new starter sure spins it up much much faster and have had no issues so far. I also replaced the plugs with iridiums at the same time, the old (original) ones looks fine. Fingers crossed it will be back to starting like it always did before.

 

[Yamacat17]

I replaced the starter today, what a difference in cranking speed then before. I pulled apart old starter and can't see anything broken or out if place (magnets all good). The brushes are definitely worn but all still there and intact? The new starter sure spins it up much much faster and have had no issues so far. I also replaced the plugs with iridiums at the same time, the old (original) ones looks fine. Fingers crossed it will be back to starting like it always did before.

Now that I look back at your pics, my starter and brushes look pretty much exactly like yours...

 

[grizztracks]

Glad to hear the new starter helped. Did you go with aftermarket for the replacement starter?

 

[Yamacat17]

I did, I went with a Kimpex...