dissecting an earthquake chainsaw

[deputyrpa]

The difference between my stock 4518 and the one I ported was amazing. The muff modded and ported quake was faster than a 025 in 12" black locust and the quake was pulling PM chain. (RS on the 025)

Did you do both intake and exhaust? Widened and lowered? I may do it, but I haven't decided yet. I'll butcher my lil Poulan 3816 first for practice.

 

[Chris-PA]

I'll give the muff mod a shot. It's got it's hands full to impress me though, in a 14" chunk of red oak, my de-catted but otherwise stock 420 Dolmar was well under half the time it took the 'Quake to bog its way through it.

You'll probably want to pull the base gasket too.

 

[MasterMech]

Did you do both intake and exhaust? Widened and lowered? I may do it, but I haven't decided yet. I'll butcher my lil Poulan 3816 first for practice.

Dive right in. I pulled the base gasket and it STILL had over .040" left in the squish band. Widened the exhaust a LOT, and slightly enlarged the intake. If I still had it I would have raised the exhaust considerably and cut the base, as it was blowing 200psi with just the base gasket out. Probably would have raised the transfers a tad too to compensate for the cylinder sitting lower by .040"

 

[deputyrpa]

Dive right in. I pulled the base gasket and it STILL had over .040" left in the squish band. Widened the exhaust a LOT, and slightly enlarged the intake. If I still had it I would have raised the exhaust considerably and cut the base, as it was blowing 200psi with just the base gasket out. Probably would have raised the transfers a tad too to compensate for the cylinder sitting lower by .040"

I dove in to the P3816. It's got plastic, slide-in transfer ports, a bead of silicone for a gasket and really small intake and exhaust ports. Pics soon.

 

[MasterMech]

I dove in to the P3816. It's got plastic, slide-in transfer ports, a bead of silicone for a gasket and really small intake and exhaust ports. Pics soon.

Cool. Would like to see the pics. I have a 38 and a 41 cc just waiting for me to get the itch.

 

[rw48]

How exactly do you modify the exhaust. I get the impression you drill or widen the muffler. Or are you working on the ports.
Just starting on doing my own work.
Thank you.

 

[deputyrpa]

How exactly do you modify the exhaust. I get the impression you drill or widen the muffler. Or are you working on the ports.
Just starting on doing my own work.
Thank you.

see my thread "Practice Poulan"

 

[deputyrpa]

Well, I dissected my Earthquake. I noticed that the piston and the top of the jug had some carbon buildup. Probably from the cheesy spark plug it came with. I got an NGK BPMR7A to stick in it. When I cleaned the piston, I also noticed that the top was not smooth, but mottled (sorry, no pic). I hope they come that way, and that mine isn't defective, because I finished done modding it. I cleaned it up, widened the exhaust and the intake ports, and reassembled it without the base gasket. The squish with the base gasket was 0.042, and with RTV it should be about 0.020 or so. It was pumping 155 psi before the mod. I'm waiting for cure, and will check the compression cold, and finish assembly tomorrow. I had already done a muffler mod.

Has anyone cut slits in the double d carb screws? If so, did you cut through the housing that surrounds them, or cut the housing back to expose the heads? Thanks.

 

[MechanicMatt]

I used foreceps to get them out, then cut slots.

 

[diggers_dad]

Unbelievable! This is the thread that won't die about the saw that won't die. I still have my first 38 cc and run it occasionally. It hasn't let me down yet.

DD

 

[MechanicMatt]

Yeah, I had a ryobi 10532, It had those darn screws. I really liked that little saw, probably shouldn't have let it go. But oh well.

 

[Rogviler]

When I cleaned the piston, I also noticed that the top was not smooth, but mottled (sorry, no pic). I hope they come that way, and that mine isn't defective, because I finished done modding it.

I noticed that as well. Mine had a little bit of casting flash that was sticking up too, which I removed as I also deleted the base gasket. I saw it mentioned before so I'm guessing they come that way.

Has anyone cut slits in the double d carb screws? If so, did you cut through the housing that surrounds them, or cut the housing back to expose the heads? Thanks.

Like others, I removed the screws to cut the slots, but I have a 42cc Homelite cheapie that I just cut through the housing. That works okay, but the screwdriver does tend to get hung up in the slots sometimes, so I elected to do this one clean.

Most on here probably won't "get" the sticker , but a pic of mine for kicks:

-Rog

 

[Deleted member 83629]

use yamabond or hondabond to seal the crankcase. i put a top end in the husq 55 one time and used RTV and in 2 weeks of constant use i had it apart because of a air leak.

 

[deputyrpa]

Yeah....you're right. I thought I might be able to get away with Ultra Black Hi-Temp Gasket maker, because that's what I have. I use it to make gaskets in tranny and oil environments, where it works well. I'll go out and get some Yamabond today.

 

[DexterDay]

Took my 58 cc Quake out for a little run yesterday. Got my new bar and chains (courtesy of MasterMech). This was a nice saw at 45 cc. Even nicer when I put the DP muffler on it. Add in a 58 cc motor and it's tons of fun now!!

Ran it against a 55 Rancher (53 cc) w/ 18"- 3/8" , a MS 362C (59 cc)w/20"- 3/8", and the Quake (58 cc) w/16"- .325. All were wearing Stihl RS.

The 55 and the Earthquake were almost equal in times. In soft wood (poplar) the Quake was a smidge faster, in hardwood (Pin oak), the 55 took it by a little.

 

[diggers_dad]

Took my 58 cc Quake out for a little run yesterday. Got my new bar and chains (courtesy of MasterMech). This was a nice saw at 45 cc. Even nicer when I put the DP muffler on it. Add in a 58 cc motor and it's tons of fun now!!

You can shoe-horn a 58 cc motor in there?!?! Direct cylinder and piston replacement? Is there a build thread?

DD

 

[DexterDay]

You can shoe-horn a 58 cc motor in there?!?! Direct cylinder and piston replacement? Is there a build thread?

DD

They sell a kit for $60 on eBay. Need to replace crankshaft as well. The 58 cc machine has a longer stroke than the 45 and 52... Or for $80, you get the entire motor, already has bigger crank, piston and cyl, just have to put your gas tank, carb, etc on there.

The 52 cc kit is just a piston and cylinder swap.



All the Chinese 45cc, 52cc, and 58cc use the same chassis and plastic size.

So yeah, it fits just fine. Pull your 45cc out and shove the 58cc in.

I posted all the pics in this thread, about 10 pages (plus or minus 20 ) ago.

 

[deputyrpa]

I cheated again. I couldn't get Yamabond locally, so I used some Permatex Copper Hi-Temp Gasket stuff. I sprayed several layers on, and let it dry. Cranked the jug on and it looks like it sealed well. We'll see. I did a cold compression test, and she blew 165 psi.

 

[Rogviler]

I cheated again. I couldn't get Yamabond locally, so I used some Permatex Copper Hi-Temp Gasket stuff. I sprayed several layers on, and let it dry. Cranked the jug on and it looks like it sealed well. We'll see. I did a cold compression test, and she blew 165 psi.

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

 

[deputyrpa]

Dag Nabbit! The engine is surging here and there, so I suppose it's sucking air. So much for the copper stuff. It's supposed to be a dressing for gaskets, and not meant to be a gasket itself. I'll wait for some Yamabond.