150 flywheel magnet threads for puller

[gsdanno1]

Anyone know what the thread size is on the flywheel magnet for use with a puller. I'm changing my timing belt and my puller seems to only have standard thread bolts. Thanks

[99yam40]

are you trying to pull the flywheel or the magnets?
never heard of pulling magnets.

do you have metric bolts?
Yamaha bolts and hole threads are metric

probably need to post complete model # of your motor so others know what motor you are talking about

[fairdeal]

Yamaha's quirky documentation

[boscoe99]

Combination flywheel and rotor for the electrical generation system. On some models it also contains a harmonic balancing device.

When Japanese gets translated there is some confusion. Like what we call the hood of a car really being a bonnet. At least that is what they said on Wheeler Dealers. Fenders are really wings.

I seem to recall the bolts being 8 mm with a 1.25 mm thread pitch. Pull the flywheel and take it to Home Depot and find the metric (excuse me SI) thread size that will fit it.

[fairdeal]

Pull the flywheel and take it to Home Depot and find the thread size that will fit it.

I see what you did there....

[gsdanno1]

I found the size. I am trying to pull the flywheel so I can replace timing belt. I am currently using a pancake compressor to power an impact on a puller. Not working , will have to wire up my big compressor. While I have everything off , I want to change the balancer as well. I don't see anything in the service manual that addresses this procedure with the power head still intact on the lower unit. Has anyone done it this way ?

[boscoe99]

A 150 does not use a timing belt.

Perhaps you have an F150.

The service manual for a Yamaha outboard motor is severely lacking in detailed information. You would be better off following the Yamaha technical bulletin for the balancer replacement which is at

F150 Balancer Replacement Instructions

For changing the cam shaft drive belt take note not to damage the tensioner.

Timing Belt Tensioner Information

[rodbolt17]

and if you are mildly dyslexic like me,
when you think you have the 20* mark lined up.
look at the TDC mark for cyl 2&3.
it will be lined up with the timing pointer.

[rodbolt17]

best I remember with no manual here at the house.
if the flywheel is off line up the keyway with the stbd side crankcase parting line.

[TownsendsFJR1300]

Balancer replacement might take an hour going SLOW...

And it can be done with the boat in the water.

I watched the tech do mine under warranty, just make sure
marks are dead nuts lined up...

[pstephens46]

Or you can remove, throw them in canal. Bolt plate back on...

[rodbolt17]

not really.
the euro commercial model did away with it.
however they also changed the ECU and lowered the max RPM.
what other internal mods were made I cannot say.

[pstephens46]

I read about the F150B model. One change was to limit max rpm to 5750. I am going on 3 years with no balancers. Same as some crabbers around here and a sht ton of coonasses (not racial btw) in Louisiana. But this is a dead horse topic anyhow....

[rodbolt17]

I had a crabber ran a few years with a shredded balancer.
when he brought it to me with a complaint of an oil alarm I asked him how long has the motor been running without sqealing.
he said it squealed for a week then quit about 11/2 years before I got it in.
cleaned the pan and replaced the strainer and cleaned the oil pressure control valve and it ran another 2 yrs with a new blancer.
it finally died with about 8500 hours on it.
most neglected F150 I ever saw that refused to die.

[pstephens46]

I had a crabber ran a few years with a shredded balancer.
when he brought it to me with a complaint of an oil alarm I asked him how long has the motor been running without sqealing.
he said it squealed for a week then quit about 11/2 years before I got it in.
cleaned the pan and replaced the strainer and cleaned the oil pressure control valve and it ran another 2 yrs with a new blancer.
it finally died with about 8500 hours on it.
most neglected F150 I ever saw that refused to die.

8500 hours. Think he replaced with an ETEC?