Saw Won't start - ECHO CS6702

[ZaccN]

Recently purchased a echo cs-6702 from marketplace and everything with the saw seems fine except it wont start.

Ive put a new spark plug in, fuel filter, fresh fuel and confirmed that the ignition coil is working.

Does anyone know of any common things to try to get this thing started ?

 

[Conquistador3]

Silly question: were you sold the saw as working or as a non-starter?

If the former, contact the seller right now and try sorting this out.
If the latter, first thing remove the air filter, fully open the throttle, put a few drops of premix directly in the throat and see if it starts that way.

 

[Wood Doctor]

Check the compression. It may be too low and if it is, that's the culprit and a top end rebuild is on the agenda.

 

[ZaccN]

Thanks for the responses. Really appreciate your help and input.

The condition when i purchase the saw was "not working" The previous owner said he hadn't started it for over 5 years.

I have tried putting a couple of drops of fresh 50:1 into the carb through the air cleaner side but it still doesn't want to go. It semi starts with the decompression valve out, choke on and a bit of fuel through the air cleaner side of the carb.

I put a compression tester on it today and is only has 48psi max. did the test 3 times. 45, 48,48. I have also put the compression tester on another saw that starts and i only get 55psi max. the other saw is 62cc so i wouldn imaging there would be much difference between the 2.

The Echo manual says it should have 110psi so i thing a top end rebuild is what is needed.

 

[ZaccN]

Does anyone know a good place to source parts for Echo saws? In particular a CS-6702 piston kit and cylinder

 

[Justin Taylor]

Well I don’t believe you have the right tester on there because a saw would not start on 55psi take off the muffler and look for scores is the easiest way to look at the engine for damage

 

[Conquistador3]

There's something fishy with those numbers: are you 100% sure you are using a compression tester and not merely a pressure gauge?

 

[Wood Doctor]

Well I don’t believe you have the right tester on there because a saw would not start on 55psi take off the muffler and look for scores is the easiest way to look at the engine for damage

Considering how much these parts are going to cost, I would first take it to a small engine shop and see what they would charge you to do it. They could also check out the compression with their tester and perhaps order the parts for you if you want to attempt it yourself. The parts you are looking for go with the CS-6700 and then you look at the serial number range. Check several possibilities. Here's one:
https://www.ereplacementparts.com/echo-cs6700-001001-023377-chainsaw-parts-c-35043_35970_36814.html
But, Echo also has a site for parts direct:
https://www.echo-usa.com/Products/C...MI8vy_0Jyx5wIVZCCtBh1SBg_pEAEYBSAAEgJegfD_BwE

Good luck!

 

[ZaccN]

Thanks again for the suggestions in solving this.

I am using car compression tester kit. is that a certain brand/type for small engines ?


I removed the muffler today and could see some marking on the piston. i the proceeded to taking the cylinder off and discovered a lot of scoring on the exhaust side of the piston and the rings flush and jammed in.
The cylinder is not too bad but there is some light scoring just below the exhaust port that a finger nail can catch on.

My question now is, should i buy a replacement piston and rings and hone the cylinder slight and see if that works ? or bite the bullet and spend the money and get a new cylinder straight up ?

Some pictures below for you guys
https://imgur.com/a/5J5352U

 

[Conquistador3]

Those compression numbers are still strange: below 50psi is extremely hard to get because the engine will stop working at around 90psi. We'll get back to this later.

Anyway, before honing the cylinder try seeing if the lining is still sound and if the scoring around the ports is not too deep. From the pictures it looks like the cylinder can be salvaged but it will take a bit of effort, but pictures don't tell how deep scoring goes.
Before proceeding any further however you should try and find out why that saw seized. It could be straight and/or bad gas, but from here I cannot rule out an air leak as well. Maybe you should budget new crankshaft seals and a cylinder gasket just to err on the safe side? They are cheap insurance.

Now let's talk spare parts. I don't know what prices you get on Echo spare parts in Australia: they could be cheap like in the US or expensive like in Europe. While ordering spares in the US is tempting, always factor in shipping from and to there is simply horrendous. When all is said and done it may be just cheaper to source the parts you need locally.

 

[ZaccN]

Thanks for the quick response Conquistador3.

When i was purchasing the saw, the owner said that he hadn't started it for 5 or so years and it just sat on the shelf in his shed. The first thing i did when i got it home was empty the fuel and bar oil tanks. The Bar oil tank had pretty new looking Car engine oil in it and the Fuel deffinitely was not 2 stroke. It had an purple and orange like tinge to it and not a blue/green tinge like my mixed fuel does. I dont know much more about the history of the saw. The tank was full like it had just been filled up too.

The parts are hard to come by here in Australia and a US or a Uk site is going to be one of the best bets. So far from what i can gather is that the Piston kit is relatively cheap but the Cylinders are expensive. The only place online in Australia that has a pison and cylinder kit for an Echo saw ( not a Cs-6702) is selling it for $325.99 AUD On the ereplacements site a piston kit is $69.99 US plus postage

I have a local small engine shop that is an Echo dealer. I will have to see what he can get and how much they are before i purchase them.

 

[Conquistador3]

There are all hues of two stroke oils out there: the Echo/Shindaiwa full synth (labelled as "Made in Japan") we get here is deep blue while the Repsol full synth I usually use is urine yellow. But still five year old unleaded gasoline is poison for any engine and if it's oxygenated doubly so.

Right now I would focus on honing the cylinder and see if you can get a satisfactory finish: there's always time to order a new cylinder down the road.
Asking the local shop doesn't cost a dime and may find they are actually good. Or to be avoided at any cost.

 

[Jkstihl]

Can we get some pics.

 

[ZaccN]

Pictures can be found via the link here
https://imgur.com/a/5J5352U

 

[ZaccN]

Ordered a genuine piston kit online yesterday. Wont arrive untill 18th March

 

[Conquistador3]

Ordered a genuine piston kit online yesterday. Wont arrive untill 18th March

That's pretty normal with Echo/Shindaiwa outside the US market: if it isn't in stock at the dealership or at the importer expect to wait a few weeks.
In fact given the CS-6702 is out of production that's not a long time to wait at all: I am still waiting for a bunch of crankshaft seals from Shindaiwa which are used on current models and have no idea when they'll turn up.

 

[ZaccN]

Hi everyone,

just an update for you. The new piston kit arrived last week and still no luck with compression. My local shop had a secondhand jug off a CS-680 that i thought i would bolt up and see what would happen.
The saw still wouldn't start but felt heaps better on the pull, much stronger compression.

I poured a little bit of mixed fuel down the opening on the carburettor and wah la, it fired straight over.

The saw has a Walbro HDA-203 Carby on it and i've put a new diaphram kit in it but the fuel is still not getting through the carby and into the cylinder.

Has anyone had similar issues like this and what did you do to fix it ? I am really hoping to not have to buy a brand new carby.


Thanks,
Zacc

 

[Woodanhor]

Hi everyone,

just an update for you. The new piston kit arrived last week and still no luck with compression. My local shop had a secondhand jug off a CS-680 that i thought i would bolt up and see what would happen.
The saw still wouldn't start but felt heaps better on the pull, much stronger compression.

I poured a little bit of mixed fuel down the opening on the carburettor and wah la, it fired straight over.

The saw has a Walbro HDA-203 Carby on it and i've put a new diaphram kit in it but the fuel is still not getting through the carby and into the cylinder.

Has anyone had similar issues like this and what did you do to fix it ? I am really hoping to not have to buy a brand new carby.


Thanks,
Zacc

Have you checked or replaced fuel lines?
Try setting carb to initial settings

 

[ZaccN]

Fuel is getting to the carb. I've sprayed It all down with carb cleaner but that's about it.

What are the initial settings for these carbys/saws ?

 

[Woodanhor]

Fuel is getting to the carb. I've sprayed It all down with carb cleaner but that's about it.

What are the initial settings for these carbys/saws ?

I looked quick at manual I only see rpms listed
Did you get a manual already?

Heres a post that talks about it
https://www.arboristsite.com/community/threads/echo-6700-carb-settings-max-rpm.234536/

Edit: take a note of current settings by counting the number of turns in and write it down