flywheel puller

[albert1]

Hi all,

Can you use a good quality heavy duty 3 prong clamp type puller to remove the flywheel from a force 90hp or do you have to use an Harmonic puller ?

I have seen a post on iboats stating Harmonic pullers can strip the threads in the flywheel and another poster stated that he broke three Harmonic pullers trying to remove a flywheel. Conversely another post stated never use a prong type puller but did not state what the problem with that type is.

The decision for me is do I rent a heavy duty Clamp type puller for ?5 which looks like it could pull the flywheel of a 6 L diesel, or buy a Harmonic puller kit for ?25 which looks rather light and seems made to remove auto steering wheels.
From what I have been told Mercury/ Force use their own brand puller tool which is of a special design unlike either the Harmonic or Prong pullers.

Advice from persons with first hand experiance would be most welcome.

regards Albert.

 

[pnwboat]

Re: flywheel puller

If the flywheel on your 90 HP Force engine has three bolt holes around the center, then it was designed to be taken off with the harmonic balancer type of puller. Using the puller that grips the outer edge of the flywheel may cause damage.

You may have to heat the center area of the flywheel with a propane torch. Make sure the three bolts that attach the puller to the flywheel are threaded in as deep as they can go. Tighten the large center bolt of the puller down good and tight. Take a hammer and strike the top of the large center bolt in a downward motion, like you're trying to drive the bolt into the flywheel. If it doesn't come loose, check the center bolt and tighten down again if necessary. Strike the top of it again in a downward motion with a hammer and it should come loose. Don't be wimpy about striking the bolt, just make sure you hit straight down and not from the side. What you're trying to do is to break the bond that the rust and corrosion has created between the flywheel and crankshaft.

 

[albert1]

Re: flywheel puller

Thanks mate,

Will give the Harmonic puller a go, do you happen to no the size of the 3threads on the top of the flywheel, looks like quater inch to me, or is it metric 6mm, if its imperial and people have been using metric it might explain why some people have been stripping threads. the engine is a 1993 or 94 force by mercury.
Albert.

 

[ezez]

Re: flywheel puller

It's 1/4". Pulling the flywheel was a PIA on mine. I used a cheap harmonic puller. I used grade 8 bolts in the three holes. I heated the middle, pryed, pounded etc. It finally came loose but it took the better part of an hour.

 

[albert1]

Re: flywheel puller

Thanks again,
Is the nut in the centre of the flywheel standard thread, anti-clockwise to slacken off or the opposite, also the nut looks like 3/4 socket size to me is that right ?.

 

[pnwboat]

Re: flywheel puller

Not sure about the size on your motor. I have a 1988 125HP. The nut on mine is 1 1/16". Standard thread, not reverse thread. Lefty loosey, righty tighty.

 

[Frank Acampora]

Re: flywheel puller

Clean the internal threads on the flywheel before you but bolts in them. Make sure that the bolts are threaded in at least 1/2 inch so you don't strip them out. If by chance you do strip them, just re-tap to 5/16 inch.

Use a harmonic puller or a steering wheel puller. If you have an impact gun, use that to tighten the center screw and the flywheel may just pop off for you. If not, rap the center screw with a heavy hammer. You can heat the center of the flywheel and it may also pop it loose.

Don't forget to use the proper cuss words---they really do help.

Tighten the center nut back to 90-95 Foot Pounds when re-installing the flywheel.

I made my own puller out of 3/8 thick plate steel and a 1/2 X 20 grade 8 center bolt