dolmar saws

[nmurph]

It is possible that the saw is in the early stage of a lean seize. The limiter may have fooled the operator/tuner into thinking it was properly tuned when it was actually lean and bouncing off the limiter.

 

[stihl 440]

I like my 2rings on my 385's pistons for that reason :msp_tongue:

 

[nmurph]

.......and I like a two pound lighter saw. I don't know what difference two rings would make? And many saws are single ring.

 

[mdavlee]

JJ and some of the others that cut production said the single ring saws needed a new ring and/or piston about every 600 hours. If that saw was used logging it may be ready for a piston and ring.

 

[madhatte]

My only complaint with Dolmar is their lack of a dealer network. I think that really hurts the saws themselves, in that if anything breaks (it will), it has to be ordered from somewhere. In a production setting, that's not OK. Otherwise and in all ways, I think the 7900 is the best bang for the buck on the market today.

 

[Chopper G]

Since I am 61 years old and only cut for fun, 600 hours is equal to about a lifetime of use, not a big deal...:hmm3grin2orange:

600 hrs seems pretty short, to me.

A pro using the saw 6hrs a day would have to re-ring and/or piston-swap the saw every 100 days of use, or 2.6x a year. Something tells me that Dolmar would not enjoy the reputaion it has if its pro saws required top-end tear-down 2-3 times a year.

 

[Anthony_Va.]

600 hrs seems pretty short, to me.

A pro using the saw 6hrs a day would have to re-ring and/or piston-swap the saw every 100 days of use, or 2.6x a year. Something tells me that Dolmar would not enjoy the reputaion it has if its pro saws required top-end tear-down 2-3 times a year.

:agree2:

Alot of guys run them 60hr/week. Thats having to tear the saw down every 10 weeks. Not for me. If that info is right. Thats at least four times a year replacing rings. Does seem pretty short.

If it were me, I'd get a 660 or 390xp. The 7900 may be just as fast, but I don't think it could handle 36" wood for as long as a 660 or 390. If I were logging with the saw every day, I'd want the one that could pull the bar with the least stress on the saw. JMO

 

[mdavlee]

That seemed short to me too but that is what some said they were doing. 600 hours of run time I would imagine would take more than 100 days to get. I really doubt the saws are actually run 6 hours a day.

 

[madhatte]

They're also really easy to work on.

 

[mdavlee]

I can't find the thread where some of them were talking about how long a single ring lasted vs the two rings. I know someone said it was 600 hours or so and the single rings were loosing compression and power. 600 hours of runtime is going to take a long time to accumulate that. I know people might work 60 hours a week but the saw isn't running all of that.

 

[Anthony_Va.]

I can't find the thread where some of them were talking about how long a single ring lasted vs the two rings. I know someone said it was 600 hours or so and the single rings were loosing compression and power. 600 hours of runtime is going to take a long time to accumulate that. I know people might work 60 hours a week but the saw isn't running all of that.

Yea, you're right about that. Maybe every 6 months to a year. Most guys I know swap out their saws after a year or two anyways. The saw does get ran alot of the day really though when logging. I would say about 50-60% of the day once you get into the cutting. Some days are different though.

 

[Chopper G]

That seemed short to me too but that is what some said they were doing. 600 hours of run time I would imagine would take more than 100 days to get. I really doubt the saws are actually run 6 hours a day.

Was this Dolmar-specific, or just "generally speaking" for a hypothetical single ring 2 stroke motor?

 

[mdavlee]

I can't remember and can't find it now. :bang: If you run a saw hard and have to replace a $15 ring once a year that isn't that bad for money invested vs money made in a pro setting. Most of us won't wear a saw out in 5 years. I know the dealer that's about 2 hours from me run a 7300 and 2171 as his main saws logging. He sold saws on the side and evenings. He was tearing them down every 2 years and putting new rings in.

 

[parrisw]

I got a chance to check the compression today after work. It is only about 160. The saw starts and runs just fine but I am thinking that 160 is a little low. It pops on the third pull with the choke set, then it starts with the fourth pull with the choke off. It isn't pristine but I have seen much worse. :hmm3grin2orange: Do any of you know what the lower compression limit is on one of these things?

Nice saw, aint nothing wrong with 160.

 

[bowtechmadman]

160 don't think I'd be worried a bit. Make sure it's tuned corretly and run the dog snot out of it.

 

[rms61moparman]

160 is great!
Run it 'til it hits 125 and slap another ring in it.


Mike

 

[Andyshine77]

160-psi means the rings are seated pretty good, most 7900's start out around 150, but I have seen a few with 180/190-psi right out of the box.

 

[Andyshine77]

thanks for the info I would expect 180 from a new one, the ring seems to be a little out of round the edge shows some grooves, I think I will pull it down and get the aluminum off the cylinder and put in a ring...cant hurt and it is cheap....:hmm3grin2orange:

My Poulan 4200 blows 180 as well as my Homelite 923. Those are the numbers I like to see

No reason for a new ring here, you're likely not going to gain any compression without adjusting the squish, 160-psi is above normal. Keep in mind we are dealing with metal to metal contact, it is normal to see some light scuffing/rubbing. To keep this to a minimum run 32:1 race oil.

 

[parrisw]

If you take it apart, clean out all the carbon from the ports and combustion chamber. Wont hurt to replace the ring, just don't expect the compression to get any higher.

 

[stihl 440]

Yea, you're right about that. Maybe every 6 months to a year. Most guys I know swap out their saws after a year or two anyways. The saw does get ran alot of the day really though when logging. I would say about 50-60% of the day once you get into the cutting. Some days are different though.

More like 70% to 80% of the day for us...and we run 8hr days...unless its a contract job and nice days sometimes we put in 10's. 600hrs seems really short...i know the amish logger that i talk to all the time..he has 066's and 660's that have 4years of logging on them..and they still run real strong.....never had the top ends off of them...and i know they run their saws pretty hard all day long....they also have a 460 that i think is 3 years old...never touched it either...he said he used to run 395's and he go 4 years out of them as well.......he was gonna trade in the 066 and buy a new one just beacuse of its age...i said he11 no!!...run it till it quits...and let me know when it does ill buy it!!..lol And my boss has a 046 in the woods truck and i think its 7 years old...it has ALOT of logging hours on it...and it still runs strong! Sad part of it is...he braggs up the dolmars pretty heavy but we all use the stihls more..lol I dont know...to each his own...im a husky and stihl man...mainly huskys but i dont have anything really against stihl either.....but i can honestly say that the dolmars dont impress me...they arent a poulan...but they aint a husky or stihl either in quality and reliability.but if you ask me 7900 vs 385xp=385xp wins every time.....7900's have the rpm for the small wood...but not the raw grunt power of the 385xp for the big trees. I've seen it and ran both ALOT....385 always comes out on top..regardless of what any cookie cutting movie tells you....