Dolmar 6400 BB spun crank & other problems

[BuckthornBonnie]

Problematic Dolmar with 3yrs average run time on an AM big bore kit. Wouldn't idle, carb wouldn't tune/- piston had excessive wear but no scoring. Stripped it down and found this:

"Spun" crank, flywheel side. Slip fit into both old and new bearing. Had a noticeable rock with flywheel off.

 

[BuckthornBonnie]

And-




Caber rings, HD filter upgrade.
I didn't build this saw, but did supply the kit from Weedeaterman... I liked the looks of it.
Here's the kicker- my buddy never told me that he noticed the crank play. He asked a local mechanic who said it's probably fine. Lesson learned; only build a saw on a good bottom end. It'll eventually fail if you don't.

 

[TreeLife]

Thorough inspection saves a lot of heartache my friend, lesson learned. Snag some parts from some of our illustrious members here and put some good oem parts on the Ole girl. @Miller Mod Saws

 

[Angelr]

[QUOTE = "BuckthornBonnie, post: 517151, member: 1725"] Y-

[Adjuntar] 90418 [/ ATTACH]
[INCLUIR] 90419 [/ ATTACH]

Anillos Caber, mejora de filtro HD.
No construí esta sierra, pero sí proveí el kit de Weedeaterman ... Me gustó la apariencia de eso.
Aquí está el pateador - mi amigo nunca me dijo que él notó el juego de manivela. Le preguntó a un mecánico local que dijo que probablemente estaba bien. Lección aprendida; sólo construir una sierra en un buen extremo inferior. Finalmente fallará si no lo hace. [/ QUOTE]
I've seen that in more cylinders, I do not think it's a crank problem

 

[BuckthornBonnie]

Thorough inspection saves a lot of heartache my friend, lesson learned. Snag some parts from some of our illustrious members here and put some good oem parts on the Ole girl. @Miller Mod Saws

Yep. I never build up a questionable bottom end. He got bad advice lol.

 

[TreeLife]

Yep. I never build up a questionable bottom end. He got bad advice lol.

If it was me I would contact Mr miller for the bearings and perhaps a ported top end and new piston. It will really rip after that, Carl knows his way around a Dolmar.

 

[BuckthornBonnie]

[QUOTE = "BuckthornBonnie, post: 517151, member: 1725"] Y-

[Adjuntar] 90418 [/ ATTACH]
[INCLUIR] 90419 [/ ATTACH]

Anillos Caber, mejora de filtro HD.
No construí esta sierra, pero sí proveí el kit de Weedeaterman ... Me gustó la apariencia de eso.
Aquí está el pateador - mi amigo nunca me dijo que él notó el juego de manivela. Le preguntó a un mecánico local que dijo que probablemente estaba bien. Lección aprendida; sólo construir una sierra en un buen extremo inferior. Finalmente fallará si no lo hace. [/ QUOTE]
I've seen that in more cylinders, I do not think it's a crank problem

Poor plating quality? Dirt ingestion?

 

[BuckthornBonnie]

If it was me I would contact Mr miller for the bearings and perhaps a ported top end and new piston. It will really rip after that, Carl knows his way around a Dolmar.

We are thinking of parting it out.

 

[TreeLife]

We are thinking of parting it out.

Whaaaaat?!

 

[BuckthornBonnie]

Whaaaaat?!

Haha, I know...I know. It's a 6400 that needs a crank, bearings, gasket/seals, p/c, etc. The case threads are suspect as well.
I'm a Stihl guy... if it were a different model then I'd probably do it up.

 

[TreeLife]

Haha, I know...I know. It's a 6400 that needs a crank, bearings, gasket/seals, p/c, etc. The case threads are suspect as well.
I'm a Stihl guy... if it were a different model then I'd probably do it up.

I can't like this lol

 

[BuckthornBonnie]

I can't like this lol

Haha, it's sacrilege.., I know.

Anyone need parts? Pretty much everything else is ok. I think my buddy is done with it, but I'll confirm.
We could probably trade for a decent 046-660 project (w cash on our end if needed).

It had previously scored the original top end.

 

[SOS Ridgerider]

Post up some pics of what you have, and what you're looking to get for it. I'm always looking for Dolmar stuff.

 

[TreeLife]

Lol back off Sondre!

 

[SOS Ridgerider]

Lol back off Sondre!

Never! Lol

 

[blsnelling]

F-Cast rings?

 

[BuckthornBonnie]

F-Cast rings?

Ahh... Good question and I thought the same thing at first.
As far as I know it was a regular Caber ring. It made decent compression but nothing great. I ran this saw a few times--/ it was "ok" and comparable to an 044/440 (despite being 85ish cc).

 

[BuckthornBonnie]

Tank, handle, 2 carbs (one AM), 32"bar, 18"bar (maybe), air filter upgrade, newish AV, all fasteners... should be used but in decent shape.
The case worries me: it had a failed case gasket that someone epoxied (that failed, too). The case screws came out in what I can only describe as a "biased" feel. There's a few signs that it was dropped. I wonder if it was dropped hard enough to load the crank/bearings and cause this failure.

 

[blsnelling]

Ahh... Good question and I thought the same thing at first.
As far as I know it was a regular Caber ring. It made decent compression but nothing great. I ran this saw a few times--/ it was "ok" and comparable to an 044/440 (despite being 85ish cc).

I think F-Cast rings now come standard on most pistons.

 

[BuckthornBonnie]

I think F-Cast rings now come standard on most pistons.

Think they're too hard for weaker plating?