Yamaha 25 HP 2-stroke hard starting

[JimS123]

The motor is a 2007 model. I also own Evinrudes that are 1988 as far back as 1953 and all start 2nd pull. I asked this question 2 years ago but didn't really get a good answer.

The motor takes 8 or 9 pulls to start. I asked my local Yami dealer mechanic and he said check the choke. I pulled off the plastic cover and found that the choke on the bottom carb was open maybe 1/64". Not adjustable so I bent the linkage. Now both butterflies close tight.

The next time out it started on the 3rd pull. A week later I went on vacation and left the boat in the water for a week and it started first pull every time. Then I came home and a week later it took 6 pulls. Now its back to 9 pulls each time.

The carb is left full with the hose connected all the time. I use stabil with each tank. I pump the bulb (its always hard), turn throttle to "start", choke on and pull, pull pull.

I tried to replace this POS with an Etec this year, but the 25 still has not been released.

If this is normal for Yami, I'd just like to know. Once it is running it runs absolutely perfect all day long and starts on the first pull. Its just the cold starts that are a problem.

 

[99yam40]

Re: Yamaha 25 HP 2-stroke hard starting

what is the starting procedure in your owners manual and are you following it?
without a model # it is hard to tell what motor you are talking about and what all it has on it.
Do you have a service manual for it?
Does this thing have a primer pump to add a little fuel when you pull the choke out like the J/E had? Sorry but I am not familiar with the 25

 

[JimS123]

Re: Yamaha 25 HP 2-stroke hard starting

The starting procedure in the owners manual is:
* put throttle to start
* pull out choke fully
* Pull starter cord repeatedly till it starts
* If no start in 4 or 5 tries, increase throttle
* turn off choke when it starts

Yes, I am following the procedure to the letter.

Its a 2007 Yamaha 25 HP, manual start, short shaft, model 25MSH.

No, I did not buy a service manual.

No primer pump.

 

[99yam40]

Re: Yamaha 25 HP 2-stroke hard starting

Only thing I can say is to check the basics compression, spark, and fuel. If it has good compression and spark and still does not start in 3 or 4 pulls, pull the plugs to see if they are wet, just to see if they are getting fuel at that point or if they are fuel fouled.
A service manual will give the procedures for adjusting the carbs after they have been pulled and serviced (cleaned)as Yamaha recommends. Hopefully the fuel is fresh and no water present in the tank, filter, and carb bowls

 

[surfga]

Re: Yamaha 25 HP 2-stroke hard starting

The motor is a 2007 model. I also own Evinrudes that are 1988 as far back as 1953 and all start 2nd pull. I asked this question 2 years ago but didn't really get a good answer.

The motor takes 8 or 9 pulls to start. I asked my local Yami dealer mechanic and he said check the choke. I pulled off the plastic cover and found that the choke on the bottom carb was open maybe 1/64". Not adjustable so I bent the linkage. Now both butterflies close tight.

The next time out it started on the 3rd pull. A week later I went on vacation and left the boat in the water for a week and it started first pull every time. Then I came home and a week later it took 6 pulls. Now its back to 9 pulls each time.

The carb is left full with the hose connected all the time. I use stabil with each tank. I pump the bulb (its always hard), turn throttle to "start", choke on and pull, pull pull.

I tried to replace this POS with an Etec this year, but the 25 still has not been released.

If this is normal for Yami, I'd just like to know. Once it is running it runs absolutely perfect all day long and starts on the first pull. Its just the cold starts that are a problem.

Definitely not normal. I have the exact same engine and it has never taken more than 3 pulls, regardless of how long it sat. I have gone months in between starts and it will start first pull sometimes. I never keep the fuel line connected either.

I hope you get it sorted. Ours has been a good little motor, sorry you have had troubles with yours.

 

[JimS123]

Re: Yamaha 25 HP 2-stroke hard starting

Its not the fuel, fuel lines or gas tanks. The fuel is always fresh and I have 2 different tanks that act the same.

Its done it since it was brand new. It now has about 50 hours on it.

Once it does fire, it starts up OK and the choke action is normal. What's so exasperating it that it will start with barely a half pull for the rest of the day.

PS - I should also mention that it smokes a lot when started up - regardless of whether its a cold or hot start. As soon as you shift it into gear and go its fine. I broke the motor in using the recommended procedure (50:1 for 1st tank), but then switched to 100:1 per Yamaha. I am now using a 75:1 oil mix, based on recommendations from this forum. Several have said that 50:1 should be used, so I compromised.

 

[99yam40]

Re: Yamaha 25 HP 2-stroke hard starting

I had to re read your post from the start again and I wonder about your statement
"The carb is left full with the hose connected all the time. I use stabil with each tank. I pump the bulb (its always hard), turn throttle to "start", choke on and pull, pull pull."

I have never had a motor to have a firm bulb after setting for a week or longer. Matter of fact most of the time they will need some pumping after tilting the motor all the way up and setting for a while. This will cause the carbs to lose fuel out of the bowls and when you set them back down the bulb will not be firm as you can pump fuel into the bowls to fill and then the bulb will become hard or firm.
The bulb I had on my Yamaha was difficult for me to squeeze ( just did not feel right after owning J/E in the past)when I first got it so I replaced with a spare from my Johnson. It is a lot more flexible and easy to squeeze. I can tell when the carb bowls are full as the bulb gets hard and no more fuel can be pumped. There are several possible problems with yours:
it is not getting enough fuel to start out with and the fuel pump has to pump enough into the carbs before it can fire up.
It has fuel fouled plugs and it takes some airing out to get the right mix to fire.
the motor has bad/ weak compression
Or the motor is not firing some times
My bet would be on not having the fuel needed in the carbs at cold start. But that is just my opinion.
Have you pulled and cleaned the carbs or at least drained to make sure they did not have water or trash in them. Yamaha says to pull and clean as routine maintenance

Do keep us informed on what you find out as the problem, because it will help others when they do searches for their problems

 

[JimS123]

Re: Yamaha 25 HP 2-stroke hard starting

Starved for fuel at the beginning is my theory as well.

I have 2 tanks that I use - one is a new one with the OEM Yamaha hose and bulb. The other is an OMC tank with the connector replaced with a Yami part.

On every other motor I have ever had, I used to always pull the line at the end of the day and run the carbs dry. I have left the hose connected with this motor to ensure that there is fuel available. Truthfully, I never noticed a difference with the 2 types of bulbs.

The motor is only tilted at the end of the day for 5 minutes or so to load the boat back on the trailer. Likewise, a 5 minute additional tilt when relaunching.

The first time out at the beginning of the season and it takes several pumps of the bulb to fill the carb bowls. But I swear after that a week later it won't take any additional priming. You squeeze and the bulb is hard.

 

[99yam40]

Re: Yamaha 25 HP 2-stroke hard starting

I do not know what else to look at unless the float needles are sticking in the seats and finally open up letting fuel into carbs or maybe the rings are sticking and there is not a lot of compression at first until they come loose and start sealing properly.
You could do a compression check after it has sat for a while and then do another after it has run and see how big of a difference there is.
Do you use ring free? If it smokes that much it maybe building up carbon.

 

[JimS123]

Re: Yamaha 25 HP 2-stroke hard starting

The owner's manual says to use ring free so that's what I have been doing.

 

[BaitThrower]

Re: Yamaha 25 HP 2-stroke hard starting

This happens to my 30Hp 2-stroke Yammy as well. Basically the throttle never stays at the start position after you crank on the cord, it spring loads back to idle and I need two hands to yank ojn the rope because there is good compression on the motor... Same deal, 8-9 pulls to start but then fine all day and starts on first pull. I found the trick is to have a second person hold the throttle open a little extra past the start position while you crank and then it kicks over quicker on a cold start.

It doesn't really bother me to be honest and I dont see it as a problem really. It's just not getting fuel until you crank it a few times with the throttle open.

 

[ENSIGN]

Re: Yamaha 25 HP 2-stroke hard starting

I agree that the primer bulbs do feel funny,try putting a clear piece of hose between the fuel pump and carb so you can see if the primer bulb is really pumping enough fuel.If not I would try a different brand of bulb.GL Ted

 

[fishwalton]

Re: Yamaha 25 HP 2-stroke hard starting

Interesting thread.........think I will talk to my mechanic and see what he says.

I have a 2006 Yamaha 25 hp., 2 cycle, electric start. When cold it always requires 2 grinding start attempts (choke engauged) and does not fire. On the third start, it starts. The rest of the day it starts with only a slight touch on the electric start button, choke not required.

It starts much harder than my old 1973 Johnson 20 hp, which the Yamaha replaced. I'm the second owner of the Yamaha and only owner of the Johnson until it was sold.

Had decided the hard starting was just inherent with this motor, but after reading the thread I'm now wondering if this is normal.

 

[junkyardwarrior]

Re: Yamaha 25 HP 2-stroke hard starting

Interesting thread.........think I will talk to my mechanic and see what he says.

I have a 2006 Yamaha 25 hp., 2 cycle, electric start. When cold it always requires 2 grinding start attempts (choke engauged) and does not fire. On the third start, it starts. The rest of the day it starts with only a slight touch on the electric start button, choke not required.

It starts much harder than my old 1973 Johnson 20 hp, which the Yamaha replaced. I'm the second owner of the Yamaha and only owner of the Johnson until it was sold.

Had decided the hard starting was just inherent with this motor, but after reading the thread I'm now wondering if this is normal.

Old post but worth mentioning.

assuming the fuel is 100% excellent quality. Poor fuel quality will get you nothing but trouble and what I'm fixing to mention is meaningless with less than ideal fuel.

Take the black plastic silencer off of the front of the carbs. 4 phillips head screws one on each corner. Don't drop em.
Pull the manual choke lever all the way out.
See if the choke plates are closing ALL THE WAY (no gaps between the plates and carb).
If there is any gap, you'll have to fool with the links a little to get them to shut all the way. I usually bed the little tab on the bottom carb's choke lever. Just a little is all it takes usually. I have seen them where one is fully closed (bottom carb) and the top is open an 1/8". In a case like that I just made another connector link out of a coat hanger wire. Or you can bend the link in the middle which will shorten the link and pull the top choke closed more.
main thing here is to make darn sure they're closing COMPLETELY-meaning zero gap or less than 1/32" at the very most.


Next thing to make sure of is that the throttle plates open just a little when the twist grip is moved to "start". On the 25 Yamahas, I usually like to just twist the grip in neutral until it won't twist any more and then see where the butterflies are. They should open a little bit. Fast idle should be about 3000 RPM give or take-that's how you know it's set correctly. There is a stopper on the right side of the engine, a phillips head screw with a jam nut. Most of the duck hunters here just take the screw completely out so that if it's flooded, they can open the throttle a ways and they'll start faster. Also helps if the engine is dead cold and it's 15? outside. Remember...this is an old school 2 stroke. You need to get the choke plates completely closed and the throttle butterflies open at least a little. This causes air pressure to drop behind the choke plate which pulls fuel through the main jet at a high rate-which starts the engine.

 

[darkerheart]

Re: Yamaha 25 HP 2-stroke hard starting

my new 20hp was the same,9 pulls at the boat ramp but at home with the muffs was fine.after many trips to the dealer and after an older mechanic there had a look it was a simple adjustment to do with the timing,a screwdriver and 5 seconds,now good,helps when the right personal do the work and not young no-it-alls,a dealer stuff-up from day 1 but a simple fix.also start it in the down position if possible as this affects the floatlevels.also someone has said about the throttle moving from the start position,mine has a wing-nut to maintain revs so i tighten this on the start position when pulling the cord to keep it in the right position.

 

[jspriddy]

Re: Yamaha 25 HP 2-stroke hard starting

I'm certainly no expert on Yamaha's, or any other for that matter, but it's my understanding that Yamaha's are somewhat cold-natured. Mine, a '94 25 hp electric, certainly is, and others I know with Yamaha's say the same thing.

John

 

[32holland]

Re: Yamaha 25 HP 2-stroke hard starting

my new 20hp was the same,9 pulls at the boat ramp but at home with the muffs was fine.after many trips to the dealer and after an older mechanic there had a look it was a simple adjustment to do with the timing,a screwdriver and 5 seconds,now good,helps when the right personal do the work and not young no-it-alls,a dealer stuff-up from day 1 but a simple fix.also start it in the down position if possible as this affects the floatlevels.also someone has said about the throttle moving from the start position,mine has a wing-nut to maintain revs so i tighten this on the start position when pulling the cord to keep it in the right position.

You mave have saved the day! I have a 2010 25 MSH, it ran great the first couple months and has started terribly ever since. Yah the last 3 years! I brought it back to where i bought it when it was about a year old. They charged me $300 ( should have been under warranty as far as I'm concerned) and rebuilt both carbs and installed new plugs. It continued to start awfully hard, sometimes 20 pulls! I've owned numerous old OMC's which all started in 2-3 pulls and I was disgusted with this POS. The dealer insists its fine. I checked the timing with a timing light, was reading 4-5 rather that the required 7! Can't wait to let it sit a few days and see how it starts, I'll reposts as this could save others from needlessly suffering as I have.

 

[darkerheart]

Re: Yamaha 25 HP 2-stroke hard starting

i still find that if it sits for a few weeks it still is hard to start but if i start it once every week no problem,just a fuel thing i,m guessing very annoying,i would,nt buy another yamaha,not impressed at all.

 

[darkerheart]

Re: Yamaha 25 HP 2-stroke hard starting

i thought it was maybe getting better to start but i was only kidding myself,a few mates have yamahas as well and they are similar,hard to start if sitting for more than 2 weeks.i finally solved the problem,i sold it ,never yamaha again,made the mistake though of taking it to another dealer to give it 1 more chance but what a waste of $300.

 

[32holland]

Re: Yamaha 25 HP 2-stroke hard starting

i thought it was maybe getting better to start but i was only kidding myself,a few mates have yamahas as well and they are similar,hard to start if sitting for more than 2 weeks.i finally solved the problem,i sold it ,never yamaha again,made the mistake though of taking it to another dealer to give it 1 more chance but what a waste of $300.

My timing was off by 2-3 degrees, I too thought i had it fixed. It started 1st pull the next two days, tehn i let it sit for a few days and I have pulled pulled and pulled. What a POS. I've been thinking of trading it in for an etec. I may try a different mechanic but from what I read its probably a waste of $$$. I've also thought of drilling a hole in the cover so I can shoot starting fluid in but I just cant bring myself to do it to a 2010. Its teh only brand new outboard ive ever owned. ive got severl OMC's from teh 60's which all start in 2-3 pulls. ABSOLUTELY DISGUSTED.