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

[Mac&Homelite]

Would anyone know the numbers on the main bearings and seals for a Makita 6401 as I would like to order them from a bearing supplier over oem.

 

[67L36Driver]

That would be worth a repair attempt.

Place magnet in the original position and clamp it firmly. Drill from the outside with a convenient size tap drill (#10-32 ?). Use a drill press. Don’t hand clobber it! Tap flywheel, clearance drill and countersink the magnet for hex socket flat head screws.

 

[usmcbuckwild]

That would be worth a repair attempt.

Place magnet in the original position and clamp it firmly. Drill from the outside with a convenient size tap drill (#10-32 ?). Use a drill press. Don’t hand clobber it! Tap flywheel, clearance drill and countersink the magnet for hex socket flat head screws.

Its missing one of the magnets all together, unknown if its a N or S polarity that is missing. I’m not going to throw it away, that’s for sure.

Been thinking about possibility of being able to modify a newer model electronic ignition mounted under the flywheel and removing all but 1 of the magnets. I’m sure some crackpot inventor out there has done it

 

[67L36Driver]

Dolmar 116 fuel cap?

I’m short one. [emoji21]

Any others fit? Stihl? Husqvarna?

 

[67L36Driver]

Prolly came off by crashing into the pole laminations on the coil frame. Loose main bearing or possibly tramp steel/iron picked up by the magnet(s).

 

[usmcbuckwild]

Prolly came off by crashing into the pole laminations on the coil frame. Loose main bearing or possibly tramp steel/iron picked up by the magnet(s).

Bearings are nice and tight, no vertical or lateral movement. There was some very minor scuffing on the pole.

 

[mgr1]

Have you another flywheel on the way?

 

[wrooster]

Its missing one of the magnets all together, unknown if its a N or S polarity that is missing. I’m not going to throw it away, that’s for sure.

how do you make a magnet with only one pole, either N or S?

because i'm thinking that every magnet has two poles.

 

[wcorey]

how do you make a magnet with only one pole, either N or S?
because i'm thinking that every magnet has two poles.

In this case the effective pole is the inward face of the magnet, to reverse the polarity it would have to be flipped opposite of the radius that it's formed to.
As they usually tend to be brittle, that wouldn't work out well...

 

[KiwiBro (deleted)]

Hi all, was just posting in a Dolmar thread and the option of a carb mod by Poleman came up, and then others have said they like the unlimited coils and now I'm thinking maybe I need to jump down another rabbit hole to see what can be done to my stock 7900. Should I turn and walk briskly away or pimp my 7900? I don't mind the limited coil and like to tune it pretty fat anyway but I would be happier if it would stay in tune when the weather changes. Currently, it warns me of poor weather on the way by falling out of tune long before the rain hits.

I've got the HD filter on it, but did keep the stock filter set-up. I like going longer between filter cleanouts with the HD filter but could swap back to the stock set-up if the general consensus is that's a better option.

What say you all?

 

[67L36Driver]

Looking for a serviceable 116 (45mm) cylinder. [emoji848]

 

[usmcbuckwild]

Have you another flywheel on the way?

I do, another member here has graciously hooked me up with one.

 

[usmcbuckwild]

how do you make a magnet with only one pole, either N or S?

because i'm thinking that every magnet has two poles.

In this case the effective pole is the inward face of the magnet, to reverse the polarity it would have to be flipped opposite of the radius that it's formed to.
As they usually tend to be brittle, that wouldn't work out well...

This explains it pretty well. If you have 2 magnets and place them on your bench, they will attract each other and “snap” together. Now if you flip one magnet over, they will push away from each other. Same idea inside the flywheel. 3 magnets are placed in such a way that they “attract” each other and the 4th one is “backwards”. The 3 magnets charge the system and the oddball magnet is the trigger.

 

[wcorey]

The 3 magnets charge the system and the oddball magnet is the trigger.

Thinking a bit more about this...
Are those plates that came loose the magnets or are they just steel and the magnets are in that outside thicker band?

 

[mgr1]

Plates are the magnets. They are glued with epoxy.

 

[usmcbuckwild]

Thinking a bit more about this...
Are those plates that came loose the magnets or are they just steel and the magnets are in that outside thicker band?

To be honest; I’m not sure. The outer band seems to be 1 piece, so if the band IS housing the magnets then my crackpot idea will be much more complicated.

 

[usmcbuckwild]

So I just pried one of the other remaining plates off and they definitely are NOT magnetic. It appears as if the magnets are iside the outer ring. Its almost as if the entire outer ring is magnetic, which make no sense whatsoever.

 

[usmcbuckwild]

Poor old wood chisel.... Got used on metal.

The outer ring is 100% magnetic. There aren’t an actual magnets, it appears to be impregnated with any “magnetic material” in specific locations. I did chip off a piece and applied it to each of the steel insert locations and one of them is definitely opposite polarity.

 

[mgr1]

So the strips are blocking the magnetic fields?

 

[usmcbuckwild]

So the strips are blocking the magnetic fields?

The strips are transfering the magnet field. My assumption is that the magnetic ring is epoxied in, steel plates are epoxied onto the ring then the entire assembly is machined to tolerence.