Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Echo => Topic started by: brettl on February 08, 2014, 09:49:50 pm

Title: CS400
Post by: brettl on February 08, 2014, 09:49:50 pm
Think I got screwed on a swap for this one. WHEN it starts, it dies in the first 5 or 10 seconds. Acts like it's sucking air and leaning out. Piston scores very visible but can just barely feel them. Cylinder has marks to. Question is, what's the minimum compression before it's toast? Gets to 90psi with 3 pulls. That seems awful low to me.
Title: Re: CS400
Post by: brokenbudget on February 09, 2014, 05:58:00 am
3 pulls isn't telling you anything. you pull until the number doesn't go up anymore. 90 would be the bare minimum.
regardless of compression. sounds like you have much bigger problems. I wouldn't run it until you get either the tuning or airleak issue figured out and ruined parts clean up.
Title: Re: CS400
Post by: mountainlake on February 09, 2014, 11:32:17 am
 Pull the limiter caps and adjust richer.   Steve
Title: Re: CS400
Post by: brettl on February 09, 2014, 05:10:32 pm
Thank you for the replies. I should have been more clear in my op, Brokenbudget. After 3 pulls, I can pull a dozen more times but it doesn't go past 90. I can't see any scores on the piston skirt from the intake but definite scores on it through the exhaust port. I'm hoping the cylinder doesn't have similar scoring but it seems to stand to reason that it will. From what I've read of this saw, I think it will be worth repairing. Thanks again
Title: Re: CS400
Post by: Cut4fun . on February 11, 2014, 08:29:31 pm
I like to see a min of 120psi
Title: Re: CS400
Post by: sharkey on February 12, 2014, 02:08:29 am
Specs show a minimum of 130psi static compression to run right.  Good would be more like 150psi.  Sounds like you need a piston and cylinder. 

Short block includes the crank;
Echo SB1100 (replaces SB1089)

P&C w/o crank, seals and related; Echo P021010574 and Echo P021036520.   
Title: Re: CS400
Post by: brettl on February 12, 2014, 03:35:16 pm
Yeah I think it's going to need a piston and rings and probably a cylinder. I swapped a rc plane I had maybe $50 invested in but could have sold outright for $125. Now I've found another CS400 in great running condition with case and extra chains for $200. Don't know whether to be happy and buy it or pissed off at myself about the trade, think I'll do both ;D.
Title: Re: CS400
Post by: sharkey on February 14, 2014, 07:39:13 am
How does that old saying go, something like; sometimes you get the bear and sometimes the bear gets you? 

Maybe the cylinder will clean up and you can get away with just a piston.  I know the cylinder plating is pretty tough on the small echos.  I wouldnt try to run it anymore untill you take it down and look.     
Title: Re: CS400
Post by: fordfairlane78 on May 20, 2014, 03:48:16 am
Pull the limiter caps and adjust richer.   Steve
I have done a lot of work on these Home Depot specials....they are extremely lean out of the box. ..like barely running lean. ....if some one used it for more than just limbing it is not a surprise that it is chewed up inside.  Typically though I have been able to get away with a bit of smoothing on the piston and a new ring.A little muffler work goes a long ways with these as well.