660 clone saw questions -direction

[Willoughby]

I have built 3 of these saws 1 for my son 1 for a friend both were stock and run well , then I built me one with a hyway 56 mm BB cylinder, when I measured squish without a gasket it was .019 so I went with that , the 2 stock saws had enough compression that if you failed to reset the de-comp after they coughed -it hurt - Im am 61 with a few health issues , but Im not that weak , at least imho, this BB saw kicks the decomp off in 1/4 of a pull , I did get it started but I think I need a D handle off a sno mobile - where can I find these ? and should I add a base gasket or run as is at .019?
also I am having trouble testing compression , Ive tested some old macs 65 psi and 100 psi , but I cant get a good enough pull for these chinesium 660s , maybe I am getting weaker , Im using a tester ive had for years , im a retired auto tech , some where I heard auto comp tester may not work for saws ? I cant see why not -but educate me -Im here to learn -tell me how to test compression on these C660s & point me to the D handles please --any help -advise much appreciated, thanks in advance for any and all replies

 

[Nutball]

I have a question for you: Does the bottom of the piston go higher than the bottom of the exhaust port with that big bore kit?

Also, are you using the popup piston?

 

[Willoughby]

no pop up , I didn't check port timing , maybe I will take a look, one thing I did notice the exhaust port was larger than normal width , I fit the gasket to port then to muffler had to trim a lot more off sides of both than normal.

 

[Nutball]

Yea, you just need to take the muffler off and turn the crank to TDC. It would be great if it didn't open the exhaust port to the crank case like other 660 big bores.

 

[Willoughby]

it starts, idles and revs, Ill pull muffler and look tomorrow

 

[Wonkydonkey]

I'm not saying the op does or don’t, but I had a 660 bb which Freeported, I cooked it milling..
Anyhow I got a hyway bb, one of the transfers was a few deg from the other, but I sorted that.
The squish was around 20 iirc. And it does not Freeport

But getting onto the decomp closing, I thought I’d read that some have drilled the holes slightly larger or got husky decomps

As for the D handle... a few have fitted them... iirc you can get them on the bay.. from definitive Dave......
https://www.ebay.com/itm/New-Genuin...622140?hash=item341fba99bc:g:3hgAAOSwb0BeKdkI

 

[Willoughby]

Yea, you just need to take the muffler off and turn the crank to TDC. It would be great if it didn't open the exhaust port to the crank case like other 660 big bores.

no free port on exhaust , and yes to Husqvarna de comp, got 2 d handles ordered

 

[MustangMike]

I prefer the Stihl Elastostart handles, a little larger and they have "cushion".

I had a Big Bore that was impossible to start (I developed a 2 handed pull to start it), so the builder took the saw back and raised the exhaust some.

I think the saw now runs stronger and is easier to start, so check the exhaust timing and I would make it 100 or lower. It will make a big difference.

Also, compress your solder several times to check squish to make sure you are not off on that.

 

[MG porting]

Funny I took the ported big bore off of one of my 660s and put one of my ported standard bore cylinders on it and the saw is way stronger than it was and I ported them both to same I'm wandering if its because of the Freeport.

 

[MustangMike]

Often when they increase bore size the internal transfers shrink, making the increased displacement unproductive.

My best running 660s are standard bore, but the big bore Doc built for me is close.

 

[67L36Driver]

From the information I have received, the Stihl coil employs a bit of retard to aid startup. The Farmertec does not.

I have a Farmertec MS460 clone that I cannot start at all.

 

[MustangMike]

I have not had that problem and have used a # of the AM coils on 440, 460 and 660 saws.

 

[MustangMike]

Your clone may have another problem such as hydro lock or poor cylinder timing.

 

[MG porting]

From the information I have received, the Stihl coil employs a bit of retard to aid startup. The Farmertec does not.

I have a Farmertec MS460 clone that I cannot start at all.

Is it just to hard for you to pull it over?? If so make friends with using a decompression valve on it and make sure you're close with your carb settings I would set them at 3/4 out on the low setting and 1 & 1/2 on the high setting that's what most of the clone 440 and 460 carbs want to run at but spend a little more money and put a OEM tank vent on it and a OEM carb you can get those pretty cheap.

 

[67L36Driver]

Just hit BIN on an OEM coil.

I’ll report later. [emoji1696]

Good to know on the Farmertec carb setting wise. [emoji6]

 

[MG porting]

Just hit BIN on an OEM coil.

I’ll report later. [emoji1696]

Good to know on the Farmertec carb setting wise. [emoji6]

If you replace the carb with a hd17 or hd16 you'll be very surprised and happy on how it will run I've modified two of the farmertec one's and still the OEM carbs out perform the AM one's.