DOLMAR/MAKITA The Official Sachs Dolmar Dolmar Makita Dolmar Chainsaws Thread

[Desko74]

Hi,
I would like to ask you.... if I may.
My 7900 full brand new.... not even started yet.
That was my plan to transform the muffler before start to work.
I'am thinging I have to adjust the carb. after the muffler mod.
Iam planning to make little bit richer.......1/8 turn to the "H" against clock wise.
Will it be enought? Or I should have to go with 1/4 ...?

 

[Sagebrush33]

Hi,
I would like to ask you.... if I may.
My 7900 full brand new.... not even started yet.
That was my plan to transform the muffler before start to work.
I'am thinging I have to adjust the carb. after the muffler mod.
Iam planning to make little bit richer.......1/8 turn to the "H" against clock wise.
Will it be enought? Or I should have to go with 1/4 ...?

I find it oddly humorous of @RI Chevy liking this post ..... LOL

 

[RI Chevy]

I didn't offer any help though. Lol

Ocean State

 

[Desko74]

I find it oddly humorous of @RI Chevy liking this post ..... LOL

?

 

[RI Chevy]

?

Just a joke.

Ocean State

 

[Woodslasher]

?

@RI Chevy is notorious for saying he can't tune a Dolmar right, so we give him a bit of a hard time about that.

 

[av8or3]

Hey fellows, I have a question. Are there guide bars out there other than Dolmar bars that will bolt right up to my 7900? I looked on eBay and found a Sachs-Dolmar branded 28” in ,404 that looked interesting. Just don’t know if it will fit my saw. Thanks!

 

[SOS Ridgerider]

Hey fellows, I have a question. Are there guide bars out there other than Dolmar bars that will bolt right up to my 7900? I looked on eBay and found a Sachs-Dolmar branded 28” in ,404 that looked interesting. Just don’t know if it will fit my saw. Thanks!

If it’s the same one I saw on there, it’s a 14mm mount bar for the older saws, like
133, 143, 166, etc. Oregon called that a D033 mount. The oiler hole is in the same spot as a D009 bar, but the slot is 14mm instead of 9mm.
I have a couple of D033 mount bars that I run on my 7900s with spacers on the studs from 14mm to 9mm, so yes, it’s definitely doable and pretty easy.

 

[av8or3]

Thank you!

 

[Desko74]

Wilhelm,
Sorry to bother You! Could you answer me the post #6104 ?
I am courious about your oppinion.
Thank you.

 

[Johnmn]

Wilhelm,
Sorry to bother You! Could you answer me the post #6104 ?
I am courious about your oppinion.
Thank you.

After a muffler mod yes you usually end up needing more fuel. It might be 1/8 turn or so but you will have to retune the saw either by ear or with a tach or both.

 

[Desko74]

After a muffler mod yes you usually end up needing more fuel. It might be 1/8 turn or so but you will have to retune the saw either by ear or with a tach or both.

Thank you.
I have a tachnometer. How much is the proper rev?

 

[Johnmn]

Thank you.
I have a tachnometer. How much is the proper rev?

Do you have a 7900 or a 7910? One has a 12,800 coil, one has a 13,500 coil

 

[Desko74]

Do you have a 7900 or a 7910? One has a 12,800 coil, one has a 13,500 coil

I have a Makita EA7900 (us far us I know it is equal Dolmar PS 7910. ) It means it is come with 12800,am I right?

 

[Johnmn]

I have a Makita EA7900 (us far us I know it is equal Dolmar PS 7910. ) It means it is come with 12800,am I right?

Correct it should have a 12,800 coil

 

[Desko74]

Correct it should have a 12,800 coil

In this case, not even necessary to tune the carb. 1/8 richer?
The saw is brand new,not started yet. But the muffler has been already modified, us my pictures shows above.

 

[Wilhelm]

Wilhelm,
Sorry to bother You! Could you answer me the post #6104 ?
I am courious about your oppinion.
Thank you.

Yes, retune after muffler mod.
I tune to max engine rpm with a tach.

Dolmar PS-7900 & Makita DCS7901 = 13.500rpm
Dolmar PS-7910 & Makita EA7900 = 12.800rpm

 

[Desko74]

Yes, retune after muffler mod.
I tune to max engine rpm with a tach.

Dolmar PS-7900 & Makita DCS7901 = 13.500rpm
Dolmar PS-7910 & Makita EA7900 = 12.800rpm

Thank You!

Please verify me. Am I right or not?
The new saws factory setting is not the max. rev . And unfortunately coil is controlling the speed as well . It causes double protection for the engine.
Therefore if I do not tune the carb, after the mufflef mod, it can not be any damage.... Am I rigth?
Only I will hear ignition failure, because the coil controll (12.800) disable the speed? Therefore I sould have to make it richer,
until the ignition faliure will disappear?

 

[Wilhelm]

The saw should be set to optimal/safe rpm in the factory, but variables like altitude and choice of fuel can and will influence the carb tune.

General consensus is to tune the saw under load while making a bucking cut!
The engine should 4-stroke (burble; brap...brap,,,brap) when the load is lifted, but clear up to a continuous tone when loaded (eeeeeeeeeeeee).

I personally tune by tachometer to max engine/coil rpm, this makes these saws run on the rich side when they have a muffler mod.
I am rather safe than sorry.
Also, I tend to switch between 18/20/24/36" bars without re-tuning - the richer tune makes me feel safer when utilizing the 36" B&C setup.

Please keep in mind that the coil limiter only prevents/protects Your saw from OVER REVVING, the coils rpm limiter will not protect Your saw from running too lean as the "in cut" rpm's are considerably lower than the coils max rpm!
This is regarding a factory stock saw with only a muffler mod.

If any of the above is incorrect I am certain someone more knowledgeable than me will chime in and correct me!

 

[RI Chevy]

12,800 limited coils should be illegal!