Needs help with new DOLMAR 5100

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Quadrafire2

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Hi,

I am a new member in need of some information/help:dizzy: .

First of all I wanted to thank everyone here for sharing all of this useful and great information:) . I am an amateur chainsaw user, I have a Quadra Fire insert stove that I have been using for the last 8 years. Most of my firewood I used to buy but with the prices of wood going for $250 a cord or more I decided to “fetch” my own firewood.

My fist chainsaw was, and still is the Husqvarna 141 with 16” b/c. I have been using this saw for the last 3 years, it is a great saw that I used it for felling and bucking some black cherries (~20” diameter) and oaks (mostly branches) that I have around my property.

I new I needed a new more powerful saw mostly for bucking 4 to 7 cords of firewood a year. I did a search found this forum and did a lot of reading. I decided to get a new Dolmar PS-5100S and I was just doing a final search to see if there was one on ebay and to my surprise I found a used one for sale by a Pawn shop! I got it for $201 delivered! I thought it was a good deal…

When I got it I fist inspected it and it looked like it had the original DOLMAR bar and had a date code of 0511 (November 2005)! I removed the top cover and the filter looked clean, after further inspection I decided it is time to start it, three pulls with chock and one pull in center position and it started right up! Like I mentioned I am new to chainsaws so I can not really tell if it is tuned correctly but it idled smoothly and responded well to throttle changes.

I ordered a new 18” 3/8 b/c from Amick’s (Tony was very helpful) and also had to get the new boot insert, it did not have one, and a new spark plug gapped to 0.5mm. I checked the compression and had to pull start 7 to 9 times to get the needle gage to stop moving and it stopped at around 175 PSI. I tried a few times and got similar results every time.

Now finally to my question (sorry for the long introduction) with all the readings it sounds to me that this saw is very powerful but when I try to buck large logs 20” to 24” in diameter, with the spikes in and some good pressure the saw bogs down and stops! I have to release the pressure for it to continue cutting. Is this normal or is there something wrong with this saw? If I do not put pressure it seems to cut well but from the readings it sounds to me that it should not stop the chain from moving when I put pressure on it!

I ordered a new larger 3/8 20" b/c from Amick's but I wounder if the saw has enough power to move it after last experience:confused: .

Any help would be greatly appreciated.

Rony
 
Sounds like you are asking too much from a 50cc saw...I know my 026 will not let me "dawg in" when using the 18" bar. Try to cut with out leaning on it.

Don't waste the money on a 20"b&c, get a 60cc or 70cc saw for the bigger stuff. A 7900 would be sweet
 
From what I hear, the 5100 is a screamer, but you have to let it work at its own pace. Pushing almost any saw into wood will make it bog down. After you cut with the saw for a while you will find a good combination of pressure and cutting speed. Play around a while and if you think it isn't running right, take it to the nearest dealer and have them tune it for you. Welcome to the site and good luck.
 
2000SSM6,

Thank you for your reply. That is what I was afraid off... For some reason I must have missed this in all my readings. I thought the 5100 with 3.8hp was powerful enough but I guess it is not true, I should have gone for a bigger saw.

Rony
 
510

Oddly enough, my ps510, 1 step down from the 5100, seems to do really well. Depends on what I'm cutting though. In hardwood, say hard maple or oak, you can really lean on it, but can put a little pressure on it and work it back and forth it really cuts like a champ. I'm getting the 5100 for the extra .6hp. In softwood it does VERY well. My 510 has about 3 full cord, 9 face cord through it as well as 20 or 30 blocks ripped from this weekend and last week. I'm soooo impressed with it, hence why I decided I want the 5100 for christmas. Remember one thing, the newer saws are made to cut fast, not have torque. This was the hardest thing I had to learn. Also, try adjusting your carb, that can make a HUGE difference with speed and torque. Good luck bro and get to using that new saw buddy... Cheers eh?

:cheers:
Dude
 
2000SSM6,

Thank you for your reply. That is what I was afraid off... For some reason I must have missed this in all my readings. I thought the 5100 with 3.8hp was powerful enough but I guess it is not true, I should have gone for a bigger saw.

Rony

Oh, it's got the power. That saw smokes in the cut at around 14K and needs to eat the wood by itself. I keep a 3/8 16" on my 026, that seems to be a perfect combo. It is mostly used as a limbing saw anyway.

Try to keep the saw in it's upper rpm's and see if it cuts better...
 
What kind of shape is your chain in? Do you have to push hard on the saw to make it cut?

Steve
 
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Thank you for you help everyone!

The b/c are bran new from Amick's, It seems to be cutting fine if I do not put pressure on it but if I dig the spikes and pull up, the saw stops. I can only put a little pressure, is that normal?

I played with the H screw adjuster, it was all the way counter CW at the limiter, so I removed the limiter and tried to go out further. I think it go worse! Is that possible?

Thanks,
Rony
 
Before you mess with the jets anymore, I would take it to a shop to have it tuned, unless you are confident in your work. The incorrect jetting could damage your saw.
 
I agree with plant biologist it probably needs tuned by a shop with a tach. It sounds like it is running too rich it will run stronger a little leaner but if you go too lean you will kill the saw so take it to a shop. My friend has a husky 350 that eats up some wood with an 18 bar by what I understand the 5100 is a lot stronger than the 350 so get it tuned and let us know how it does.
 
PlantBiologist,

I might just do that but if possible I like to work on my own tools/equipment/cars myself to some degree. I am not trying to be a smart**s but is it really so difficult with tuning a carburetor? There are three adjustments H L & S, all you have to do is first back the top speed H adjuster all the way out CCW, then set the idle with the S adjuster, set the H for top speed (this might be a little tricky to do by ear but possible), check for smooth/fast acceleration with the L adjuster and finally fine tune idle adjuster S again.

Is this too difficult to do? Am I taking a chance?

Thanks,
Rony
 
JT78,

The last thing I want to do is kill the saw! I know if it will run too lean it will destroy the piston. I am probably going to take it to the dealer soon.

By the way I thought that making it richer it will cut stronger (more pollution though) and not the other way! Am I wrong on this assumption?

Thanks,
Rony
 
PlantBiologist,

I might just do that but if possible I like to work on my own tools/equipment/cars myself to some degree. I am not trying to be a smart**s but is it really so difficult with tuning a carburetor? There are three adjustments H L & S, all you have to do is first back the top speed H adjuster all the way out CCW, then set the idle with the S adjuster, set the H for top speed (this might be a little tricky to do by ear but possible), check for smooth/fast acceleration with the L adjuster and finally fine tune idle adjuster S again.

Is this too difficult to do? Am I taking a chance?

Thanks,
Rony

Not a smart__ at all. We all like to work on our own saws and encourage everyone to. A carb out of adjustment could cause your saw to quit and require a major repair.

I am not the expert on this subject, Lakeside has a wealth of knowledge though. Tuning a carb can be done without a tach, but you should have experience doing this before hand. You shouldn't turn the jets all the way out CCW, since you removed the limiting caps. Most carbs, as far as I am familiar with, recommend turning both L and H jets all the way in CW, and then backing them out 1 to 1.5 turns CCW. This is your rough adjustment and vary depending on the saw and type of carb, and final adjustments should be made from here. Please someone interject if I am wrong. With a used saw that didn't seem to run correctly to start with, I would have it done professionally the first time so you know what it should run and sound like.

Tuning a carb is not difficult, but it is easier after you have done it a few times. I still have mine double checked at the shop before I start sawing, but I am just paranoid. Good luck and let us know how you make out.
 
[QUOTE
Now finally to my question (sorry for the long introduction) with all the readings it sounds to me that this saw is very powerful but when I try to buck large logs 20” to 24” in diameter, with the spikes in and some good pressure the saw bogs down and stops! I have to release the pressure for it to continue cutting. Is this normal or is there something wrong with this saw? If I do not put pressure it seems to cut well but from the readings it sounds to me that it should not stop the chain from moving when I put pressure on it!

I ordered a new larger 3/8 20" b/c from Amick's but I wounder if the saw has enough power to move it after last experience:confused: .

Any help would be greatly appreciated.

Rony[/QUOTE]
That saw should do ok w/ 20 in bar, although I wouldn't expect it to feel like it would w/ say a 16in.
I have an 032 ( W/ a 20 in. 3/8 p. b&c.)I mounted an aftermarket electronic module on the top cover.
Ok , the reason I bring it up is because it ran quite like what it sounds your Dolmar does not long ago. I actually run it about 30 minutes bucking some 15 inch oak and started pushing it hard and fast to see if it was flawless and only when I pushed it hard and fast it would make about 1/2 a cut before it would kinda miss and bog ,then die if I tried to keep it going in the cut. It would start back up and clear out and run good until I would really push it hard and fast again. I richened it up slightly and it didn't get better. The top cover felt very warm, almost hot and I perceived the module being mounted on it above the cylinder may be getting to hot and mal functioning. So when I got her home I stuck some aluminum tape underneath the module between the cylinder and top cover to divert some of the heat away from the module. I also installed a new NGK plug for the standard Bosch which looked Ok. Took it back out and I haven't got it to die or bog out yet since. (All done at very warm temperatures)
If I were you I would try a new spark plug and make sure your carb is clean and properly adjusted. If your saw sounds like it isn't getting enough fuel it could be fuel delivery and usually the saw dies out and your spark plug stays clean and dry. If your plug looks cruddy or dark,mabe wet ,perhaps your ignition is failing when hot.( I have been assuming when you said your saw stops that the engine was shutting down.) If the saw doesn't seem to run normal and you are unsure what to do, do not keep running it as you could cause further engine damage. Have an experianced saw mechanic check it out. Air leaks or a crack in the carb could cause it to burn to hot and damage your piston and cylynder. A good service center could pressure check it and get a better idea where to go from there if it isn't a simple fix.
 
check the chain

take a few thous off the riders. also if you are pushing then the chain is dulllllll:chainsaw: sharpen the chain when it starts slowing and throwing sawdust not chips.
Just My Ber Monies Worth
Cheers Mates:cheers:
 
If it is running too rich it will cause it to run poorly pull the spark plug if it is white it is too lean if it is black too rich it should be a light brown color. The best way to set a saw is with a tach (unless you have the experience to set one by ear and even then you can be off by +/- 500 rpm). If set right that saw should scream through some wood as long as the chain is sharp and the rakers are allowing the teeth to bite in. You already stated that it was a new bar and chain so I would assume the problem is either the carb or the ignition. Trust me it is worth spending 20 or 30 dollars to have it set or you could spend 50 bucks on a tach so you can do it yourself in the future as well. You do have to admit that 50 for a tach is better than having to buy a new saw in the longrun. Good luck hope this all helps.
 
Thank you for you help everyone!

The b/c are bran new from Amick's, It seems to be cutting fine if I do not put pressure on it but if I dig the spikes and pull up, the saw stops. I can only put a little pressure, is that normal?

Yes, the way it sounds - let the saw do most of the work, not you!

I played with the H screw adjuster, it was all the way counter CW at the limiter, so I removed the limiter and tried to go out further. I think it go worse! Is that possible?

Thanks,
Rony

Yes, it will run strongest when just right.

A tach is a good investment, when tuning newer saws, without beeing very experienced at it.
 
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Here is a pic of the spark plug from my 359 which is set at 13,200rpm

Pic100.jpg
 
Your 5100 will handle 20"-24" wood, but lightly "dog in". The saw has to do most of the cutting. It was made for smaller wood.
 
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