Dolmar 5100s died

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Months ago a thread was posted about 5100's running lean. I mentioned in the thread that my dealer [D&D enterprises-Salem Indiana] cut a notch in the rubber gasket under the air filter. This foam gasket makes the atmosphere side of the diaphragm pull air through the air filter. Dealer says plugged air filter equals not enough fuel pumped to carb equals burnt up saw. I don't know if this is true or not but my saw is still running fine.
I did have to have the coil replaced.

A plugged air filter doesn't equal a lean saw. The fuel diaphragm is pumped by the case pressure. A dirty filter equals a rich running saw because there is more fuel than air.

It sounds like this saw has been run lean. 6 months of weather makes a huge difference in saw tuning. Since it is now cold, air is more dense. The colder it is, the more fuel you can add. So if this saw was set up when it was 70 degrees (lean from the factory to boot) and hasn't been adjusted at all since then, this cold weather may push it over the limit in terms of a leaned out air/gas mix.
 
huskystihl
Senior Member

Join Date: Mar 2008
Location: ohio
Posts: 324


Ps in dolmar should be pos post #84
This thread covers this problem with the 5100.
 
A plugged air filter doesn't equal a lean saw. The fuel diaphragm is pumped by the case pressure. A dirty filter equals a rich running saw because there is more fuel than air.
epicklein22, if you look at the carb you will see that the atmosphere side of the diaphragm not the crankcase side is required to get its air through the air filter. That is the purpose of the foam gasket!
 
A plugged air filter doesn't equal a lean saw. The fuel diaphragm is pumped by the case pressure. A dirty filter equals a rich running saw because there is more fuel than air.
epicklein22, if you look at the carb you will see that the atmosphere side of the diaphragm not the crankcase side is required to get its air through the air filter. That is the purpose of the foam gasket!

So is this saw's carb similar to the intelli-carb system stihl uses?
 
Another :heart: lovely :heart: Dolmar story!

Have to wonder about Dolmar.

Sounds like these things are junk to me. Feel bad for the dealers that are trying to defend these things. I'll take a 346 or an ms 270 anyday over one of these turds.
 
epicklein22, sorry I know nothing of intelli-carb system. I do not think 5100's are junk. However,I do think the factory tried to get to fancy with this setup. The 7900 is not designed like this.
 
It's quite possible that the dealer was trying to take me for a ride. All I know is that after I told him that no way was I going to pay for the repair and that if the job weren't done under warranty, I would have him take the new parts off and I'd take the saw home and fix it myself and after I left those messages with the distributor, the problem was suddenly resolved.

Chainsaws don't play a big role in my life, but I know enough to keep the air filters clean and to check the plugs from time to time, especially on a new saw, to make sure they're not running too lean. Neither dirty filter nor running lean were involved here. I suspect a manufacturing defect, but, as I said, I'm no expert.

My other two saws, a 028WB and a 031, are both about 30 years old and, as such, pre funny fuel and limiters on the needles - so that's all new to me. They have never given me any sort of trouble that required dealer intervention. They did get so rickety and hard to start from old age that I took them to an independent tech who works for a dealer, and he declared them non-repairable. That's when I bought the Dolmar. But since I hate to throw away things that look repairable to me, I sought advice here, and with that and some elbow grease I got them back into perfect working order. So, even though the Dolmar was out of action, the Stihls saw me through nicely.

So far the repaired Dolmar is behaving well, and I hope it will continue to do so because I really love the way it makes firewood.

You did good. Sounds like your telling him the parts would come out if no under warranty got the ball rolling there, good for you. That was very odd the way I see it. He's waiting on warranty approval after he's already done the saw, doesn't make sense to me. If they said no and you said you wasn't paying either what was he planning on doing, keeping the saw untill someone pays. I'm glad you got it striaghtened out and all turned out well.

I have a 5100 I like very much. Its a mean little saw, really has some gonads for a 50cc saw. I haven't used it very much and its taching right at 14,500 and seems to run good, real good.

If I were you I wouldn't put a whole lot into all the negative posts about that saw. That little saw and Dolmar in general creates alot of attention on this site, maybe more so than anywhere else. I hardly heard of Dolmar untill I came to this site. In my area they are mostly unknown. This site has been very good for Dolmar so natually should one fail its gonna be reported right back where it was first read about and inquired about, here. So your going to see some negative posts but in the big picture overall the saws failing and reported on this site are very small compared to the big picture overall across the country.

Run that saw and not worry about it.
 
Sounds like these things are junk to me. Feel bad for the dealers that are trying to defend these things. I'll take a 346 or an ms 270 anyday over one of these turds.

From my experience in Stihl and Husky shops that sell around 1200+ units a year and work on several times more than that, all brands have thier different problems with certain makes/models/componets over the years. Some are taken care of faster than others within the companies that make them.

I am not a die hard fan of any brand. I just like the good stuff and there are many good models and manufactures, not just Stihl and Husky. I refuse to be brainwashed by any of them and claim they are the best. There are just to many factors to be taken into consideration.
 
k&n ftw?

Hmmm.. kinda like K&N 2 stroke air filter oil for dirt bikes & quads?

Has anyone modified the stock airfilter with K&N material?

That is probably our best bet not having to clean these filters so frequently.

1m setting Epoxy, fine cuts making sure the piece is bigger than the area it will replace so that it's not sucked in, especially the small areas??

The bottom part of the filter will be tough, but PROBABLY doable...

Going to go stare at the airfilter for awhile...I have an extra K&N hanging around.
 
epicklein22, sorry I know nothing of intelli-carb system. I do not think 5100's are junk. However,I do think the factory tried to get to fancy with this setup. The 7900 is not designed like this.

Well, I still don't know how a dirty filter will cause any saw to run lean. If it truly does cause a leaning condition, there should be wayyy more dead saws out there...
 
Well, I still don't know how a dirty filter will cause any saw to run lean. If it truly does cause a leaning condition, there should be wayyy more dead saws out there...

What he's saying is that, in theory, if the atmospheric vent on the metering side of the carburetor is plugged, the diaphragm would not be able to flex (and open the needle valve) like normal, therefore restricting the flow of gas. (On this series of Dolmar saws, this particular vent is not out in the open air like many other saws, instead it is connected to the air filter via a foam seal). However, I seriously doubt the probability of that, the amount of air space/flow needed to allow that diaphragm to operation properly is minuscule. IMO, Unless the air filter were somehow completely, totally sealed off, (not possible...the saw would quit long before it gets to that state), even a "plugged" air filter is not going to affect the operation of the metering diaphragm at all.
 
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Has anyone modified the stock airfilter with K&N material?

I looked at the outerwears pre filters for the filter but really couldn't see anything that may work..

but a outerwear will cost the same, if not more than what a new filter will cost...

I would think that any filter oil would help make dust stick to the filter, but would also make the carb run a bit richer dew to the less air getting through the filter.
 
What he's saying is that, in theory, if the atmospheric vent on the metering side of the carburetor is plugged, the diaphragm would not be able to flex (and open the needle valve) like normal, therefore restricting the flow of gas. (On this series of Dolmar saws, this particular vent is not out in the open air like many other saws, instead it is connected to the air filter via a foam seal). However, I seriously doubt the probability of that, the amount of air space/flow needed to allow that diaphragm to operation properly is minuscule. IMO, Unless the air filter were somehow completely, totally sealed off, (not possible...the saw would quit long before it gets to that state), even a "plugged" air filter is not going to affect the operation of the metering diaphragm at all.

Thanks, explained it perfectly.:bowdown: I thought I might have been loosing my marbles.:biggrinbounce2:

I am going to say the cold weather (with the carb adjusted for warmer weather) + a lean setting at the factory lead to the failure of this saw.
 
Thanks, explained it perfectly.:bowdown: I thought I might have been loosing my marbles.:biggrinbounce2:

I am going to say the cold weather (with the carb adjusted for warmer weather) + a lean setting at the factory lead to the failure of this saw.

I'm thinking so too...our regional rep warned us to check RPMs on ALL PS-5100's before we sell them...that being said I have yet to see one that was running dangerously lean.
 
From my experience in Stihl and Husky shops that sell around 1200+ units a year and work on several times more than that, all brands have thier different problems with certain makes/models/componets over the years. Some are taken care of faster than others within the companies that make them.

I am not a die hard fan of any brand. I just like the good stuff and there are many good models and manufactures, not just Stihl and Husky. I refuse to be brainwashed by any of them and claim they are the best. There are just to many factors to be taken into consideration.

I gave the 5100 a shot based off reviews and price and they didn't hold up. I'm not brainwashed and am willing to try new and different brands. This is first hand field testing and if you do a search on this model many of them have failed and not just under comercial use, usually the weekend woodcutters are having failure as well. I ran a 7900 and was impressed but no way would I trade the proven performance and reliability of say my 460 for the johny come lately of the saw world. To each his own I just will never own one again.
 
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