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

[FederalQ]

 

[EchoShindaiwaMakitaDolmar]

It had not been fueled prior to last week when I fueled it and started it to make sure it ran.

It has the HD filter with the foam cover on it. I’ll try it without

Did removing the foam cover off the filter help at all?

 

[hbabler]

Did removing the foam cover off the filter help at all?

It did not. That being said I ran it today and it behaved perfectly

I’m wondering if it just needed to be broken in a bit. I’ve never owned a new saw before so is that within the realm of possibilities?

 

[eric4]

I'm taking delivery of a burned up smurf blue DCS6421, snagged on ebay for a nice price. Quickly put an order in on an HD filter kit (since this saw was missing filter and top cover anyway) and an 85cc big bore.

Now, I'm already reconsidering my route, after reading thru this thread more. Since I'd like to keep this saw, to replace my cs-7310, an OEM 7900 top end sounds like a better idea. It also sounds like the HD filter hinders air flow fairly significantly, so I'm going to attempt to setup a redbeard 2" v-stack adapter, with this aliexpress foam filter. Eyeballing the dimensions, it looks like this setup might fit under the low top filter cover, so we'll soon find out!

If this isn't cutting it on filtration, then I'll get the redbeard foam filter, and cut a hole in the lowtop cover, but I figured this would save me $50 if it works. Plus it'd look stock.

 

[eric4]

Well... the quest for the proper cylinder has been a little more frustrating than anticipated. Does anyone have a reliable source for a 7900 cylinder, with left side decomp? I found the kit for $200 at Repair Clinic, but after placing my order, they revised the price to $370! SawAgain has them for $270, which is currently the best price I can find. HLSupply has the version with top decomp for $240 shipped, but I believe that's got the SLR exhaust flange.

Anyone know if there would be a performance hit, if I used the SLR cylinder, with non SLR muffler? Would it be worth paying more for the proper 7900 cylinder?

 

[Shane¹]

You can use the regular muffler with the 7910 style cylinder with no downside. Only downside is decomp is on top right. My suggestion would be run the saw with the big bore until you find a decent price on a used OEM cylinder. Did you already buy a left side decomp cover?

 

[eric4]

You can use the regular muffler with the 7910 style cylinder with no downside. Only downside is decomp is on top right. My suggestion would be run the saw with the big bore until you find a decent price on a used OEM cylinder. Did you already buy a left side decomp cover?

Thanks for the advice! Might go that route... Reading some mixed opinions on the Big Bore vs 7900. Lots of people say they have the same power, but others are dead set that the 7900 is the only way.

My saw already has recoil side decomp cover, and I do kinda prefer the grey cover look. Already got my big bore kit which has recoil side decomp, but just found the kit on SLE Equipment for ~$230, so I put that order in as well. I've got a hunch though, that when they reach out to Makita to put in their order, I'll also get notified that the price went thru the roof. I'll wait to hear from them, and if the price does go up, I'll stick with the big bore kit.

Here are some pics of the BB kit I received. I'm no expert on determining cylinder/piston quality, so I'd love to hear what y'all think. Ring looks like a solid 1-piece design

 

[Shane¹]

Thanks for the advice! Might go that route... Reading some mixed opinions on the Big Bore vs 7900. Lots of people say they have the same power, but others are dead set that the 7900 is the only way.

My saw already has recoil side decomp cover, and I do kinda prefer the grey cover look. Already got my big bore kit which has recoil side decomp, but just found the kit on SLE Equipment for ~$230, so I put that order in as well. I've got a hunch though, that when they reach out to Makita to put in their order, I'll also get notified that the price went thru the roof. I'll wait to hear from them, and if the price does go up, I'll stick with the big bore kit.

Here are some pics of the BB kit I received. I'm no expert on determining cylinder/piston quality, so I'd love to hear what y'all think. Ring looks like a solid 1-piece design

I have a big bore a couple different 7900s 7300s and 6400. I think the big bore is pretty darn close to a stock 7900. Never ported a big bore but I have no complaints with my big bore

 

[eric4]

I have a big bore a couple different 7900s 7300s and 6400. I think the big bore is pretty darn close to a stock 7900. Never ported a big bore but I have no complaints with my big bore

Glad to hear it! Maybe I'll sit on my 7900 P/c kit, if i'm able to get it for the price I paid, and still run the big bore for a bit!

 

[Powerstroke Cowboy]

The biggest problem with the big bores is the size and shape of the transfer tunnels.

Opening them up the the same shape and size as an OEM cylinder should bring them to life.

I'm with Shane. I'd run the BB till I found a good price on an OEM cylinder.

 

[Ketchup]

Beware the cost of pistons for 7900. You may find a used cylinder for $150, but an OEM slug is another $100. The meteor pistons are cheaper, but still put you close to the cost of a full oem kit.

 

[eric4]

The biggest problem with the big bores is the size and shape of the transfer tunnels.

Opening them up the the same shape and size as an OEM cylinder should bring them to life.

I'm with Shane. I'd run the BB till I found a good price on an OEM cylinder.

Thanks! I was thinking of having a go at porting a cylinder for the first time...Maybe the big bore kit would be a good candidate

 

[Wilhelm]

I never use the DeCo on my PS-7310 , if I were to buy and install a new OEM 52mm P&C kit I'd just plug it no matter which side it's on.
My two PS-7900's feature no DeCo nor do they need one - though maybe I do not need one.

240$ on HLSupply sale actually ain't that bad, folk better stock up!

Genuine Makita Cylinder Piston 52mm EA7900P

www.hlsproparts.com

 

[Wilhelm]

Thanks! I was thinking of having a go at porting a cylinder for the first time...Maybe the big bore kit would be a good candidate

F

SOLD Thread '7910 top end. New OEM.'

Dec 5, 2024

Bought this a few years ago for a project, but didn't end up using it. $250 shipped to the lower 48.

• Flying_Dutchman
• Replies: 11
• Forum: Parts Only

• 

 

[SOS Ridgerider]

Thanks for the advice! Might go that route... Reading some mixed opinions on the Big Bore vs 7900. Lots of people say they have the same power, but others are dead set that the 7900 is the only way.

My saw already has recoil side decomp cover, and I do kinda prefer the grey cover look. Already got my big bore kit which has recoil side decomp, but just found the kit on SLE Equipment for ~$230, so I put that order in as well. I've got a hunch though, that when they reach out to Makita to put in their order, I'll also get notified that the price went thru the roof. I'll wait to hear from them, and if the price does go up, I'll stick with the big bore kit.

Here are some pics of the BB kit I received. I'm no expert on determining cylinder/piston quality, so I'd love to hear what y'all think. Ring looks like a solid 1-piece design

This is what you need. That is the left hand side decomp Dolmar PS-7900 cylinder, with the non windowed Dolmar PS-7910 piston. Best of both worlds, and the price is right. Don't confuse it with the Makita EA7900 top end, which has top right decomp and SLR step in the exhaust.
This top end was never officially offered on a stock saw here in the US, thus it saying for Makita DCS7901, which wasn't sold here.

I have stocked up on a few of these, and it's exactly what you're looking for.

Makita Genuine Part 038-130-070 CYLINDER / PISTON CPL., DCS7901

038-130-070 - This is a genuine part for Makita; not an aftermarket part.

sleequipment.com

 

[eric4]

This is what you need. That is the left hand side decomp Dolmar PS-7900 cylinder, with the non windowed Dolmar PS-7910 piston. Best of both worlds, and the price is right. Don't confuse it with the Makita EA7900 top end, which has top right decomp and SLR step in the exhaust.
This top end was never officially offered on a stock saw here in the US, thus it saying for Makita DCS7901, which wasn't sold here.

I have stocked up on a few of these, and it's exactly what you're looking for.

Makita Genuine Part 038-130-070 CYLINDER / PISTON CPL., DCS7901

038-130-070 - This is a genuine part for Makita; not an aftermarket part.

sleequipment.com

That was the same kit I ordered from repair clinic, and the price went from $200 to $375 or something... Same story with a clutch cover for this saw

Placed the order thru SLE a couple days ago for this kit and clutch cover, so fingers crossed they won't play the same game.

 

[SOS Ridgerider]

That was the same kit I ordered from repair clinic, and the price went from $200 to $375 or something... Same story with a clutch cover for this saw

Placed the order thru SLE a couple days ago for this kit and clutch cover, so fingers crossed they won't play the same game.

Awesome! They won't change the price on you. I've bought all kinds of stuff at these prices. SLE is my go to for older parts. To my knowledge they don't get parts directly from Makita. Makita doesn't have any of these older parts in stock themselves. All from distributors that still have stock.

 

[eric4]

Awesome! They won't change the price on you. I've bought all kinds of stuff at these prices. SLE is my go to for older parts. To my knowledge they don't get parts directly from Makita. Makita doesn't have any of these older parts in stock themselves. All from distributors that still have stock.

Rad! That is good to hear. If that's the case, then I'll hold out for the OEM P/C 7900 kit, for this saw.

Just got my Makita today in fact, and started tearing into it. The saw was sold 'for parts' since it said the powerhead was locked up. I assumed that it had been straight gassed, but to my glee, a nest was made in the flywheel, seizing up the recoil. Piston still has machining marks! I've freed it up now, and plan to sell the 6421 P/C for parts.


I'll have it all cleaned up tomorrow, and will test for spark, flush the carb, and soak the bearings in Marvel Mystery Oil until my 7900 kit arrives

 

[eric4]

Tore into the makita again today! Got it all clean, tested positive for spark, rebuilt the carb, and flushed out the crankcase. Looks like the piston and cylinder can be revived to run once again. The ring is currently seized up, but I'll try to free it, and clean out any carbon in the ring channel.

Still haven't gotten confirmation from SLE about the availablility and pricing on the 7900/7910 piston/cylinder kit, as well as a clutch cover... but I'll be patient for now. Having the big bore kit is certainly tempting to throw on, but the OEM kit seems worth it...

Totally stunned at the weight of this muffler - 20oz! I've got an order placed for a Stihl 460 muffler in stainless, which will hopefully be a bit lighter. Apparently they're nearly a direct fit on these dolmar saws, and come stock with dual screened ports.

 

[Wilhelm]

Gut the OEM muffler, open up the factory exhaust outlet - You'll have an awesome sounding screamer!