Dolmar 421 sprocket clutch drum options??

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Colt Marlington

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4777BBA3-7D3F-4EA7-958D-BE21D71CF0F4.jpeg Yesterday I bought a used 421 for what initially looked to be a good price when it fired right up.

I knew there was some issue with the chain, but didn’t bother to pull the clutch cover as I was in a big hurry. Looks like CAD got the best of me on this one.

Anyway, although I have a basic understanding of mechanicals in general, I’m relatively new to the finer aspects of chainsaw tuning.

The saw needs a new sprocket clutch drum, and a chain, and I was wondering if the conversion to rim sprocket is a good option. Apparently the big advantage is being able to switch to a .325 chain.

Is the rim sprocket a more durable option?

In the future, if ever needed, will I be able to replace just the sprocket at a lower price than the whole drum?

I know I’ll need a 0.2mm shim I believe is correct.
And I have to buy a new chain anyway.
And if I do the switch, I assume a new bar also?
And are there any bars that will work with the rim sprocket conversion without modification for the oiler?

The saw came with a relatively new Oregon Double Guard 16” bar. I have no idea if it is the correct bar for the saw.

In the end I just want something that works.
But if I’m going through the trouble and expense wouldn’t mind getting a nicer bar and chain, within reason, either with the stock sprocket or the rim sprocket.

I appreciate any help that you guys can give me.
I’ve certainly learned a lot in the short time I’ve been here.
 
Dolmar PS-5105 clutch drum part number 181 223 200 and 10x16x0.2 washer for conversion from spur to rim sprocket.

I would do the conversion and be done with it, easy and cheap sprocket changes with rim sprockets.

As has been said before, contact Nate @fordf150 , he can get You what is required for the conversion.
 
Thanks for the advice all.

I see both points.

Honestly, I’d like to be able to ride down to the store and pick up an OEM sprocket and go cut something. I have a newish Stihl chain off my one non-working saw(Craftsman 2.3 16”) that I believe is a match.

But I wouldn’t mind a taller profile bar like a pro-lite or a forester.
 
That skinny little bar is great on that saw.

I got a wider one for mine. I used it for a bit, and now I’m back to the skinny one. I think the stock Dolmar bar is even skinnier than the one on your saw. Just a wee bit. The saw is more maneuverable with the skinny bar.

Don’t put a big fat bar on that tiny little saw.

There’s nothing wrong with getting it working good with minimal cost.

Where’s the pic of that spur drive? How do WE know it’s pooched? And it’s hard to tell from the pics, but isn’t there lots of tooth left on that chain?

What are ya? Mr. Money Bags? Ha!
 
There’s nothing wrong with how that saw is set-up. It will cut like crazy like that. The little chain is super smoooth and quick to sharpen. The skinny bar is like a scalpel.
 
8877BB4F-7879-46E6-96CF-2C8C472038C3.jpeg FF8BA371-5C58-49C7-BFEF-060034898643.jpeg A7282018-0686-4B1F-A56E-85EEBFF31CED.jpeg
That skinny little bar is great on that saw.

I got a wider one for mine. I used it for a bit, and now I’m back to the skinny one. I think the stock Dolmar bar is even skinnier than the one on your saw. Just a wee bit. The saw is more maneuverable with the skinny bar.

Don’t put a big fat bar on that tiny little saw.

There’s nothing wrong with getting it working good with minimal cost.

Where’s the pic of that spur drive? How do WE know it’s pooched? And it’s hard to tell from the pics, but isn’t there lots of tooth left on that chain?

What are ya? Mr. Money Bags? Ha!
Ha! Well the chain and sprocket are not supposed to look like this....are they?

The chain on the old Craftsman is the one I’m hoping will fit. It’s a Stihl.
I’ll have to get out my magnifying glass to check the codes on it.
 
yup, something went sideways there. Those parts are hooped, as you are aware. Two choices; spur or rim. You'll figure it out. You're all over it.

The little Dolly deserves a good set-up, imo.
 
yup, something went sideways there. Those parts are hooped, as you are aware. Two choices; spur or rim. You'll figure it out. You're all over it.

The little Dolly deserves a good set-up, imo.
Yeah, I really like the build quality of this saw. Really solid feel to it.
 
F29335E8-42AB-4FD6-8847-39DF213D70DA.jpeg 88277596-4A89-40E8-8A03-0FA871295929.jpeg That chain on the old Craftsman has seen better days.

Sooo....
Picked up some out of package chains at the outlet store today.

From the markings, and shape, looks like a 16” 3/8x.050 Oregon 91PX 56 link, and a 3/8x.050 14” Stihl Picco Extended 50 link.
Is that right?

So I guess I’ll just be ordering an OEM sprocket/drum, about $22.
And still thinkin about a new bar, 14 or 16...? I like the Stihl chain better, but..

Anybody using a 14” bar on a 421 or 4300?

If the 14 is not a good match I could still use that chain on the 009L I suppose. Or save it for the future CS361P-14.

Also got a little 10” bar and chain that’ll fit my 2511T or the 2620 pole saw.
All four pieces for $32.48 out the door. Gotta love the outlet store. Just wish they had a new bar for the Dolly too.
 

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The link count may not match up to the link count of what the dolmer wants. Also i would buy 2 rims 1 3/8 low pro and .325. That way you can use your 325 now and when you spot a good deal on a 3/8 setup you only got to swap rims. Then run both and keep buying whatever you like more.
 
The link count may not match up to the link count of what the dolmer wants. Also i would buy 2 rims 1 3/8 low pro and .325. That way you can use your 325 now and when you spot a good deal on a 3/8 setup you only got to swap rims. Then run both and keep buying whatever you like more.
Right. Probably just run that 50 link 14" Picco Super3 on the 009L.

I think the 56 link 91PX 3/8 that I got is OEM spec. So I'll use it to get it going.
 
I run a 420 6 tooth drum on a 5100 with 3/8 full size and gained some grunt, that would be the one drawback on a 421. Do they make a 6 tooth rim?
Good point. That 421 is a high revver. Probably not a lot of low end power.
 
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