dissecting an earthquake chainsaw

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I have one of the 45cc versions that has developed what seems like a fuel starvation problem. I was planning on ordering a replacement fuel line and filter but I'm not sure if I should try and order the Earthquake item or do we know what model of Red Max this is cloned from?
 
I was having a hard time finding anything that would work myself, when I finally stumbled on some Permatex Moto Seal at O'Reilly. Apparently Carquest can get it as well. I found lots of good reviews of it on here and other sites for both base and crankcase sealing. Something else to look for if the copper stuff doesn't work out.

-Rog

I've used MotoSeal for a couple of years on several projects with no issues.
 
I bought several of the 3814 Quakes. Not bad little saws. I've spent a lot more and gotten less. Around here people want more for a beat to death Poulan Pro or plastic Homelite.

Alas, it seems the gravy train with biscuit wheels has finally rolled off the tracks. No more bay quakes:-(

What am I supposed to give people for Christmas this year now they want more for a bar chain combo than the whole saws cost??

Just curious, this thread is getting pretty long in the tooth. Anybody wear out a quake yet? A proper spark plug and MM seem to be all they "need" to run pretty good. Anything else I should consider? (No, I'm not going to port it).
 
After about 15 tanks through my 3814 it just up and quit oiling. I still have two more. One is in a box somewhere yet to be run. one has a leaking gas tank grommet so I have plenty of parts. The original is still running strong though.
 
After about 15 tanks through my 3814 it just up and quit oiling. I still have two more. One is in a box somewhere yet to be run. one has a leaking gas tank grommet so I have plenty of parts. The original is still running strong though.
Mine split an oil line and I put one from a Ryobi 1532 on it - it was much nicer. I'm curious what failed on yours. The pumps seem to be fairly robust.

Oh yeah - I also did some work sealing where the outlet oil line goes from the muffler area through the aluminium case to the bar mount. It was leaking there and not a lot of oil was making it to the bar. I used Permatex Ultra to seal it, and now it oils great and doesn't leak at all.
 
I bought several of the 3814 Quakes. Not bad little saws. I've spent a lot more and gotten less. Around here people want more for a beat to death Poulan Pro or plastic Homelite.

Alas, it seems the gravy train with biscuit wheels has finally rolled off the tracks. No more bay quakes:-(

What am I supposed to give people for Christmas this year now they want more for a bar chain combo than the whole saws cost??

Just curious, this thread is getting pretty long in the tooth. Anybody wear out a quake yet? A proper spark plug and MM seem to be all they "need" to run pretty good. Anything else I should consider? (No, I'm not going to port it).
Remove the decals!
CS3816Log-1024.jpg
And give it a little timing advance.
 
Mine split an oil line and I put one from a Ryobi 1532 on it - it was much nicer. I'm curious what failed on yours. The pumps seem to be fairly robust.

Oh yeah - I also did some work sealing where the outlet oil line goes from the muffler area through the aluminium case to the bar mount. It was leaking there and not a lot of oil was making it to the bar. I used Permatex Ultra to seal it, and now it oils great and doesn't leak at all.

I haven't investigated what exactly has failed. No oil is going anywhere, either the bar or otherwise, running or not which is why I suspect the pump over a ruptured line. I suppose it could be a blocked pickup or maybe a stripped drive gear.

One of the benefits of being a borderline saw hoarder is that if one saw doesn't run you just grab another;)
 
Hello from Romania! To Chris -PA : what kind of ignition these Quaqes have ? It is a rev limited ignition like one on the Ryobi or non rev limited ? The diference between them externally is the lenght of the first lrg of the coil, longer on the rev limited one. The flywheels are diferent, the key groove is a few degrees off .
 
Hello from Romania! To Chris -PA : what kind of ignition these Quaqes have ? It is a rev limited ignition like one on the Ryobi or non rev limited ? The diference between them externally is the lenght of the first lrg of the coil, longer on the rev limited one. The flywheels are diferent, the key groove is a few degrees off .
I don't know if the Earthquake ignition is rev limited, but mine now runs a Ryobi 1532 ignition and it does not seem to work any differently at all. Here is where I did the swap: http://www.arboristsite.com/communi...thquake-chainsaw.214984/page-154#post-4768462 The coil is just as you describe.

Mine does not like to rev very high no load - it will work just fine in the cut, and misfires when lifting in what seems like a normal way, but no load it just won't rev high. Given that, I suspect that both ignitions are limited but I do not know for sure. It may also be a carb that gets very rich once the air velocity increases, and so it never revs high enough to hit the limiter. However, the carb is a decent size for a 38cc saw, and I've been though it fairly carefully and don't see any reason that would be the case. Since no load revs don't matter and I've convinced myself that there is nothing wrong with it, I have decided to leave it be.
 
I did just the that in reverse : on aRyobi 40 cc i put a chinese coil and flywheel and now it revs much more that before. Another project was a Ryobi clone whit closed port strato cylinder and normal piston. It has from the factory a intake block whit blank strato intake,regular two ring piston,rev limited [Ryobi like] ignition.Whit a little porting , a modified muffler and non limited ignition is a lot more powerful.
 
I did just the that in reverse : on aRyobi 40 cc i put a chinese coil and flywheel and now it revs much more that before. Another project was a Ryobi clone whit closed port strato cylinder and normal piston. It has from the factory a intake block whit blank strato intake,regular two ring piston,rev limited [Ryobi like] ignition.Whit a little porting , a modified muffler and non limited ignition is a lot more powerful.
That's an interesting data point. As I said, there may be something else limiting my Earthquake's ability to rev, such as the carb or my porting job, in which case I would not hit the rev limiter anyway.

It is hard to tell if any of these ignitions are limiting, but I have several GZ4000 based saws that rev quite well. My Ryobi 1532 certainly pulls higher revs than the Earthquake, and I have a ported GZ4000 clone made by Jenn Feng in Taiwan that screams ( http://www.arboristsite.com/community/threads/my-first-strato-porting-job.250199/ ).
 
Ijust remembered : on my first project [ closed port strato cylinder and normal piston] i put a bigger carburator from a 50 cc chinese clone.Before the carburator swap the motor acted like rev limited, after it revs almost like the Ryobi 40 cc strato ported . So the carburator it seems the limiting factor on theese little clones. I have also a chinese 58 cc Redmax clone. Whith 34 mm stroke and 45 mm bore , a bigger[factory] carburator that 50 cc clones it revs like crazy[ Fuxtec kettensage 62 cc on Ebay.de]
 
So I did some mods to the CS3816 today. The squish was 0.035" to 0.040" which bugged me, so I turned the base on the lathe at work. Now it's right on 0.020".

Also I further opened the bottom of the transfers to better match the opening in the piston skirt.

It ran pretty nicely but the mixture seemed inconsistent and the purge bulb was pulling air. I'm tired of messing with this carb, so I swapped the shafts on to a Walbro WT391 from a Poulan/Craftsman. I also changed the carb inlet to a right angle tube from another junk carb - I could have just used a longer line.

It was too late to run it, but I'm hopeful it will run like I think it should now. I took some pictures of the finished jug, but the camera battery died. I'll see how it runs in the morning and post some pictures.
 
Well, I figured out why it ran so inconsistently last evening - the spark plug was not tight! Doh! Well, I wanted to try a different carb anyway, to see if that was why it did not like to rev no-load. It will be a little tough to tell now as I've changed several things at once. With the spark plug in properly I can feel a definite increase in cylinder pressure at low starting speeds.

Here was the cylinder with the previous porting work - the base is cut but it doesn't show up well in the picture. I've marked the intended change in pen:
IMG_6089-800.jpg
Here it is after grinding:
IMG_6090-800.jpg
The cylinder is not perfect, but most of those scratches are shallow and below the port.

The timing (duration) is now:
E = 147
I = 161
T = 106

Here is the WT391 installed. It will now use the splined Husky/Poulan adjusters rather than the D screws:
IMG_6095-800.jpg
It started right up with the screws as they were adjusted for the Poulan it had been in, and they only needed a little tweaking from there. It is going to get a workout today, as 2 fairly large trees fell on power lines here yesterday and I'm going over to buck up the wood. I'm cautiously optimistic as the saw feels better just playing around no load. By the way - the air filtration on this saw is excellent.

First I need to go put the 25" bar on its Chinese clone brother.
 
The little booger runs now! It has considerably more torque than it did, most probably due to the increased compression. Also, dropping the jug helped erase some of the excessively raised exhaust port error I made when porting it previously. It's really a sweet saw now. There was plenty in this mess to give it a test - I had a 16" bar on it (one of those "Tiger"-branded bars Baileys was selling with the 9-tooth tip sprocket):
IMG_1232-800.jpg
Here is the filter area after about 5 tanks:
IMG_1236-800.jpg
There's nothing in the intake although it's a little dark in this shot to see:
IMG_1237-800.jpg
These saws have a very nice centrifugal filter off the flywheel fan, similar to the ones on Husqvarnas.
 
I went over to split some of those oak rounds today, and took the Earthquake along - mostly because it had been a few days since I ran it, and that day was very busy. I wanted to see if my impression of how it ran held up. I purposely cut up some crotches that were well beyond full bar (16"), and it just cranked through them without fuss. I could bog it but I had to be ham-fisted to do so. Torque is definitely improved and it revs more willingly too. It's pretty impressive for 38cc, light and well balanced. It's not got as much power as the GZ4000/400 and clones, but it's a lot closer now - and supposedly a little lighter although I can't really tell.
 
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