DOLMAR/MAKITA Dolmar PS-9000 starting problems.

[Vonstro]

I've got a number of Dolmar saws. I like them, probably because I'm so familiar with them. I've got a strange problem with my PS-9000. I went to start it a couple of weeks ago, after putting it up last Fall, and now, suddenly, the starter pulls VERY hard. It's a big saw and has always taken a strong arm to start, but now I can barely turn it over. I pulled the spark plug and the engine turns over as expected. Also removed the muffler and carb to inspect the import/exhaust ports and everything looks clean. I'm at a stand-still. Any help would be appreciated!

 

[Squareground3691]

I've got a number of Dolmar saws. I like them, probably because I'm so familiar with them. I've got a strange problem with my PS-9000. I went to start it a couple of weeks ago, after putting it up last Fall, and now, suddenly, the starter pulls VERY hard. It's a big saw and has always taken a strong arm to start, but now I can barely turn it over. I pulled the spark plug and the engine turns over as expected. Also removed the muffler and carb to inspect the import/exhaust ports and everything looks clean. I'm at a stand-still. Any help would be appreciated!

Does it pull hard , without the plug in .?

 

[jacob j.]

Pull the starter and see if something is binding either the starter or the flywheel. It probably wouldn't hurt to pull the clutch drum as well.

 

[Junk Meister]

Is it possible your P/C lost its lubrication? My 056 Stihls tend to do exactly what you are describing. a dab of prime (fuel mix) in the plug hole or carb usually help me especially when the saws are cold in the winter. .. spin the saw over a few times before putting the spark plug back in to get the lube distributed and avoid wetting the plug/flooding the saw .. If that changes the story (saw Pulls over easier) You can Deduce your own conclusion(s). I myself acknowledge I am getting older so notice little issues like this.

 

[Shane¹]

Did you ever figure this out was the cylinder just dry?

 

[Vonstro]

I'm still working on this one. I removed the muffler so I could get a good look in the cylinder. The piston seems to move freely and everything looks good. When the plug is pulled, the machine turns over freely. As soon as the plug is replaced, I can barely pull it past one compression stroke. The starter looks fine, seems to pull fine otherwise. I'm really struggling with this one. I think I'm going to retrofit a decompression valve, but that still doesn't explain why the machine is acting the way it does.

 

[Squareground3691]

I'm still working on this one. I removed the muffler so I could get a good look in the cylinder. The piston seems to move freely and everything looks good. When the plug is pulled, the machine turns over freely. As soon as the plug is replaced, I can barely pull it past one compression stroke. The starter looks fine, seems to pull fine otherwise. I'm really struggling with this one. I think I'm going to retrofit a decompression valve, but that still doesn't explain why the machine is acting the way it does.

Any chance fuel lock up in crankcase ? after you reinstall plug , you can’t pullover , but you can with it removed ?

 

[Vonstro]

Yeah, the engine turns over nicely when the plug is removed. This is a saw that I've used for years, without a problem. This issue just popped up out of the blue!

 

[Squareground3691]

Yeah, the engine turns over nicely when the plug is removed. This is a saw that I've used for years, without a problem. This issue just popped up out of the blue!

Leave plug out , turn saw so plug hole is facing upside down , and pull over see if fuel comes out of crank case from plug hole ,

 

[Vonstro]

Just tried it, but still no help. I still can't get past one power stroke before it stops short. Damndest thing I've ever seen!

 

[Stump Shot]

Just tried it, but still no help. I still can't get past one power stroke before it stops short. Damndest thing I've ever seen!

Did you put storage oil in the cylinder when you put it up in the fall?

 

[Squareground3691]

Just tried it, but still no help. I still can't get past one power stroke before it stops short. Damndest thing I've ever seen!

I thought you said it pulls over easy, with plug out ?

 

[ErnieG]

Loose coil and magnets sticking to the flywheel...

Ernie

 

[Shane¹]

Pulls over fine without the plug in correct? Have you tried to pull it with the Killswitch off maybe flywheel key sheared and ignition is way early

 

[Vonstro]

Did you put storage oil in the cylinder when you put it up in the fall?

Yes

 

[Vonstro]

Pulls over fine without the plug in correct? Have you tried to pull it with the Killswitch off maybe flywheel key sheared and ignition is way early

I thought you said it pulls over easy, with plug out ?

Yes, but ONLY with the plug out.

 

[Vonstro]

Pulls over fine without the plug in correct? Have you tried to pull it with the Killswitch off maybe flywheel key sheared and ignition is way early

Yeah, I've tried pulling with the switch off. I've also pulled the flywheel, just to have a look behind it. Everything seems fine.

 

[Stump Shot]

Yes

Aha! That really bumps up the compression then, until after you start it up and run it, then it will be back to normal again.
A little squirt of mix down the spark hole or carburetor may wash away a bit of the oil and relieve some of the extra compression possibly. Besides getting it to fire up without too many extra pulls.

 

[Vonstro]

Well... after struggling with this problem for long enough, I disassembled the saw, and thoroughly cleaned everything. The cylinder and piston had more oil on them than I would have expected, but everything was otherwise very clean. I also took the opportunity to install a decompression valve, something I had thought about adding for the past couple of years. Everything is now back to normal. I'll add a couple of pictures.