Dolmar 5100 wont run

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compression on 5100s

most saws have anywhere from 125 to 140 psi. 5100's have higher compression for what ever reason. anything above 90psi is sufficiant. keep in mind a saw can be scored and have good compression. i had an 880 stihl with 125psi comp. and the scored piston still kept it from starting. i could feel slight drag when i pulled it over when is discoverd the scrored piston and cyl.
 
They refueled the saw with the same mix they had ran it with since we bought it. I am here and they are checking it over..T minus 30 mins before i know whats up with it.
 
Ok well the results are not too bad. It needs a carb adjustment and rebuild. They said the gas was way too rich and ate the seals in the carburetor. Compression was great and the piston has normal use scoring. The cause of the gas leaking out the muffler was the carb was just pouring gas into the motor and choking it out. The warranty is out by a month so i waited a bit too long to take it for repair and im just tired of this saw. I have decided to sell it and get me a jonesred from the same dealer i took it to as i am very impressed with the quality of jonesred and the power they have :D
 
Yeah, those carburetor parts aren't made for running gas through them!!! Just kidding, glad you are getting it fixed up, too bad you aren't willing to try running it more. Too many people are running the 5100 too high and having trouble, I think when they are tuned back a little they make a good saw.
 
oh it was good til it stopped running but i have never had a problem with stihl and i want to try jonesred so yea. Dolmar is off my list til i can trust another saw. And the carb was set at 14,200 just to let ya'll know. But they dealer said overall it was in great shape.
 
If you decide to sell it out right,put it under chain saws in the trading post. Name your price,you may be surprised what that saw brings. Personally I would go $125.00 sight unseen(ma-be more if I see pics) for the complete saw,and I'll pay the postage. I am cheap,most here would probably do better. Just put it on the trading post.
 
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Ok well the results are not too bad. It needs a carb adjustment and rebuild. They said the gas was way too rich and ate the seals in the carburetor. Compression was great and the piston has normal use scoring. The cause of the gas leaking out the muffler was the carb was just pouring gas into the motor and choking it out. The warranty is out by a month so i waited a bit too long to take it for repair and im just tired of this saw. I have decided to sell it and get me a jonesred from the same dealer i took it to as i am very impressed with the quality of jonesred and the power they have :D

Thats what they said, dayumm if that isn't a new one. I rebuilt a few carbs this evening that are over 20 years old. Didn't see any ate up seals, thats the dayummest thing I've heard in a long time,LOL I'd get rid of it too and be done with all that BS your being fed. Letter go.
 
Compression was great and the piston has normal use scoring.

Sorry, but 120 psi is not "great" compression for this saw. Not even close. And I dont know what "normal scoring" is on a piston. It shoudnt be scored at all if its not running too lean, which it obviously was. 120 psi + scored piston = wrong fuel (whether because of carb settings, mix settings or other, im not sure but its almost certainly run too lean).

The warranty is out by a month so i waited a bit too long to take it for repair

You said you bought it 6 - 8 months ago. Dolmar has a 1 year warranty. Doesnt add up.
 
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Sorry, but 120 psi is not "great" compression for this saw. Not even close. And I dont know what "normal scoring" is on a piston. It shoudnt be scored at all if its not running too lean, which it obviously was. 120 psi + scored piston = wrong fuel (whether because of carb settings, mix settings or other, im not sure but its almost certainly run too lean).



You said you bought it 6 - 8 months ago. Dolmar has a 1 year warranty. Doesnt add up.

Maybe i missed it but where did he say it tested at 120 psi?
 
Maybe i missed it but where did he say it tested at 120 psi?

He sent me a PM because I was (previously) interested in buying the saw until all of these things started not adding up. From the PM:

darmour88 said:
Took it by the dealer and they told me it needs a carb rebuild and adjustment. Piston has minimal scoring from normal use and the motor has great compression of 120.
 
oxygenated fuel

That and users who don't realize the engine is turning too tight seems to be the killer of these little screamers.

I have nothing but praise for mine, over 3 years use, many cords, and lots of clean-up work.

It's my go to saw, and always puts a big grin on my face. In fact it impressed me so much I have added 3 more Dolmars to my fleet!

There seems to be a lot of dog piling on the 5100, seems most of the problems can be traced to operator error.
 
I see a new 5100s on ebay for $345 right now. I would like to get one but have not come close to wearing out the 2 520i makitas i bought new. I say new but they were 10 years old still new in the box for $200 each. They had slightly more power than the 540 that replaced them.

These have been problem free and i do tune for the season but not much more than that. I'm not sure which dolmar model they are but they have plenty of power with a 16'' bar and full chisel chain in hard wood. Pretty sure they don't run the same rpm as the 5100s but they do have pretty good grunt with the 16'' bar.
 
Running to rich?

sure a saw can run to rich, but i have never seen rich fuel eat up a carb. i would think twice about buying from a dealer who told me that. may be the fuel is diff. from hear in the northwest. and running lean or overheating is the only way it could be scored. scoreing means something is wrong.
 
Bad luck with dealers, huh?

[blockquote]They said the gas was way too rich and ate the seals in the carburetor. [/blockquote]

And now you're going to buy a saw from the dealer who served you that steaming plate of bs?

If it were me, I'd keep the Dolmar, and learn how to service it myself. It's not like these service techs go to university for 8 years to learn carb rebuilds, although they apparently all have Ph.D.s in bull####eing out there in Texas.

As a friend of mine from Colorado who's a priest told me, "if God had wanted Texans to ski, he would have made bull####e white."
 

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