Echo cs-7310p MM help

[Red97]

Are these new 70cc echos STRATO?

No

 

[bryanr2]

Are these new 70cc echos STRATO?

No

 

[Idahonative]

I like a simple, quality design and this new Echo is definitely that. Everything is so quick and easy to access.

 

[Idahonative]

First tank today and I'm impressed. I've never had an echo run good out of the box. A MM and tune has always been a must. As @5000+ suggested earlier, I don't think the muff needs to be modified. At least not for the average firewood cutter. It doesn't seem to be plugged up like past models.

I hear others talking about how the 7310 is the weakest in it's class but it doesn't feel like it. Throttle response is good and it feels like it had loads of torque. I purposely leaned hard at times and it happily grunted like it wanted more. I know "feel" is subjective but I have some nice ported saws to compare by.

One thing I noticed was how fuel efficient it is. Took forever to burn through a tank. Not sure what Echo has done as far as combustion tech goes but look at the plug. Really even burn. And the color is deceiving. It looks light but it easily four stroked in the cut.

I give Echo a big GOOD JOB on this saw. It handles good and the anti-vib is excellent. And the filtration seems to be amazing like Mitch Webar and @andyshine77 said.

 

[5000+]

Wait till you run a couple gallons of mix thru it. Don't baby it and keep an eye on the tune.

 

[Piston Skirt]

First tank today and I'm impressed. I've never
I hear others talking about how the 7310 is the weakest in it's class but it doesn't feel like it. Throttle response is good and it feels like it had loads of torque. I purposely leaned hard at times and it happily grunted like it wanted more. I know "feel" is subjective but I have some nice ported saws to compare by.

That’s the point of a carburettor in tune.
Wait until you got it run-in.

 

[Idahonative]

So it's been determined that the muffler on this 7310 is just an empty can and has a good exhaust port. My question to you guys in the know is this: The spark arrestor screen is a pretty tight mesh in my opinion. How much will it help exhaust flow to just eliminate it?

And I'm not concerned about laws on public land prohibiting removal.

 

[5000+]

So it's been determined that the muffler on this 7310 is just an empty can and has a good exhaust port. My question to you guys in the know is this: The spark arrestor screen is a pretty tight mesh in my opinion. How much will it help exhaust flow to just eliminate it?

And I'm not concerned about laws on public land prohibiting removal.

You can, it may help some. But be better of making a larger mesh screen to keep mud wasps and other insects out, plus other debris.

 

[FergusonTO35]

Seems like Echo mufflers are either choked with catalyst and baffles or wide open. My CS-400 and 303 were the former (now fixed) and my CS-500P is as open as can be. In stock form just an open can with a screen and small deflector.

 

[Deets066]

I hear others talking about how the 7310 is the weakest in it's class but it doesn't feel like it.

Power isn’t the only factor when picking a saw. If it feels right in the hands and has features you like, then that’s what’s important.
But you are correct, power wise... it sucked hind tit compared to the rest of the class in stock form.

 

[5000+]

Once broken in, its up there with most of the class. 1 or 2 seconds longer thru a good size chunk of firewood is not that important to most. Hell, differences in chain brand and sharpening can cause that or more.

 

[Piston Skirt]

But you are correct, power wise... it sucked hind tit compared to the rest of the class in stock form.

While it is not something exclusively surprising, after a normal run in it is very on par with competition.
The 7310 gains around 10% of power after first 5-10 hours of engine operation and a bit more later.
This is quite a lot even for an Echo.
Of course it needs carburettor adjustment both new and after run in. This is something that anti-solenoid crowd has asked for very hard

And yes, the filtering system is second to none, the anti-vibe is as smooth as the best and not as flimsy as the flimsiest of the competitors. There are quite a lot of other strong features that actually make a worksaw, not just cookie-champion.

 

[Nutball]

Looks like they were trying to copy Husqvarna with the muffler. Husqy lower bolts are also super tight.

 

[smokey7]

Nice to see a non strato mag cased modern saw with a new closed 6 transfer port cylinder. Wish they chose a 50 or 52mm bore size tho.

 

[Lightning Performance]

Nice to see a non strato mag cased modern saw with a new closed 6 transfer port cylinder. Wish they chose a 50 or 52mm bore size tho.

Why?...
More weight more problems.
45-48mm jugs make good power ported on most OEM models of average middle sized saws.

 

[Piston Skirt]

Why?...
More weight more problems.
45-48mm jugs make good power ported on most OEM models of average middle sized saws.

It’s 51.
Bigger stroke (smaller bore) is even more problems for high rpm engine.
Although actually everything consists of problems making a decent emission compliant engine nowadays - combustion has to be controlled very precisely, it still has to be reliable with very little fuel to cool and oil to lubricate, still has to fit even under noise limits etc. etc...

 

[Piston Skirt]

Looks like they were trying to copy Husqvarna with the muffler. Husqy lower bolts are also super tight.

I think the diagonal seam pioneers were Solo, so that’s not particularly “copying 576”. I might be wrong but not sure if any of them had a crankcase brace there.

 

[Lightning Performance]

It’s 51.
Bigger stroke (smaller bore) is even more problems for high rpm engine.
Although actually everything consists of problems making a decent emission compliant engine nowadays - combustion has to be controlled very precisely, it still has to be reliable with very little fuel to cool and oil to lubricate, still has to fit even under noise limits etc. etc...

Shows you how much I looked into it

I been busy so my back took a giant chit... always fun.

The two newer motors in chainsaws I've had were 45 x 37.6 so the approach was not, it won't rev, it has grunt built in so let's go find RPMs. 661s have good RPM imo but lack grunt so the 37 x 56 does not really fit your mold.
Sorry, but subscribing to that, it's not possible, really does not live at my bench. Have had no trouble getting long stroke small bore motors to run very well or vice versa. I will admit RPM does make HP but little grunt. Saw needs grunt with no gear box shifting. Make it rev... then you get your HP.

Maybe I should work on more Echo saws. I'll give the 800 a shot and let you know how that goes. After that the Husky stroker motor. 40 x 56 still considering 40 x 54 that could be a BMFer imo. Jawnys 40 x 56 Squeel sure is a runner.

 

[Piston Skirt]

Shows you how much I looked into it

I been busy so my back took a giant chit... always fun.

The two newer motors in chainsaws I've had were 45 x 37.6 so the approach was not, it won't rev, it has grunt built in so let's go find RPMs. 661s have good RPM imo but lack grunt so the 37 x 56 does not really fit your mold.
Sorry, but subscribing to that, it's not possible, really does not live at my bench. Have had no trouble getting long stroke small bore motors to run very well or vice versa. I will admit RPM does make HP but little grunt. Saw needs grunt with no gear box shifting. Make it rev... then you get your HP.

Maybe I should work on more Echo saws. I'll give the 800 a shot and let you know how that goes. After that the Husky stroker motor. 40 x 56 still considering 40 x 54 that could be a BMFer imo. Jawnys 40 x 56 Squeel sure is a runner.

I think I've unintentionally written something between the lines which I had no intention to do
Anyway, contrary to the popular belief those 45x37.6 engines were made this way mostly for better combustion (read: emissions) and not for the torque.
Although in stock form they have the highest torque in class anyway, also peaking at the lowest rpms.
Needless to say the newest generation of 34cc's is living proof - older 38x30 was making less torque (and power) than the new 40x27.4.
The new one shaved off some grams too, because of smaller stroke/crank - even with all strato piping.

 

[Lightning Performance]

I think I've unintentionally written something between the lines which I had no intention to do
Anyway, contrary to the popular belief those 45x37.6 engines were made this way mostly for better combustion (read: emissions) and not for the torque.
Although in stock form they have the highest torque in class anyway, also peaking at the lowest rpms.
Needless to say the newest generation of 34cc's is living proof - older 38x30 was making less torque (and power) than the new 40x27.4.
The new one shaved off some grams too, because of smaller stroke/crank - even with all strato piping.

Well sure they were built for better/cleaner combustion cycles. Hemi chamber, very narrow squish and non strato but the muffler has a baffle to burn off more end gasses. The strato saws have mostly open hollow can mufflers. More than one way to make emissions tests.