FarmerTec 660 "Kit" - What's the latest on quality?

[Jason628]

I'll measure the base gasket later. I plan on using a hyway gasket. So for intake timing I'm getting open at 95 degrees abdc and close at 85 atdc. I think that gives me a duration of 170 degrees. Ex open at 95 atdc and closes at 85 as well and is again 170. Not sure if I'm doing this correctly.

 

[Jason628]

That sounds like a thick gasket! Usually they do not exceed .020. You should measure the gasket thickness.

Thinner gaskets can be made from soda cans, or purchased material.

I came up with .022 for the base gasket.

 

[MustangMike]

Then your squish must be tighter than what you measured!

 

[MustangMike]

The #s most use are when the Ex, Upper Trans and In open from TDC.

Are you planning to port it?

 

[Jason628]

The #s most use are when the Ex, Upper Trans and In open from TDC.

Are you planning to port it?

Not planning on porting it. I did even out the intake port a little because it looked like doodoo. I'll measure squish again. Did a vacuum test and have a leak. Pretty sure it is the intake manifold to carb flange. It is kind of a poor design. Pretty sure the stihl ring is notched around the bolts and this one is round and protrudes out like it's too big.

 

[Maintenance Chief]

Did you take off the outer ring?

 

[MustangMike]

Yea, that was my question also, you need that outer ring on there.

 

[MustangMike]

Always check the bevel on the ports, especially the lower side of the Ex which you can not see, you must "feel" it.

These often benefit from some porting. Making the Ex wider and the In lower often result in substantial gains.

Generally, on 660s, Ex in the mid to high 90s, Trans approx. 120, and intake in the low 80s will work well in conjunction with a timing advance (.020 - .030 off the key).

 

[Jason628]

Outter ring was installed for test. I checked all the ports and cleaned up all the sharp edges. Roof of the intake port was nowhere near straight. So I marked it with a ring and squared it off. Exhaust and transfers looked ok. Going to have to find a better inner ring or intake manifold combination. Might order oem.

 

[MustangMike]

I hear a lot of complaints, but I have always used the ones supplied w/o any problems, and one of my 660 is getting a ton of daily use with a pro firewood co.

 

[Jason628]

Ya... I've seen alot of mixed reviews. Fitment might vary depending on if you get a good one or not. I'll play around with it a little more and see if I can get the inner ring to fit inside better. May have intake manifold slightly crooked or something.

 

[Jason628]

I hear a lot of complaints, but I have always used the ones supplied w/o any problems, and one of my 660 is getting a ton of daily use with a pro firewood co.

So I disassembled and reassembled it several times and got it to kind of hold vacuum. Takes about a minute to drop from 20inhg to 15

 

[Jason628]

Using .050" solder I got .027 for squish with hyway pop up and base gasket.

 

[MustangMike]

It is generally most accurate when you go to the left or right of the plug, in line with the pin (eliminating piston rock) and cycle the saw several times to crush the solder as much as possible. It often springs back a bit if you just do it once.

 

[Nutball]

You should use twisted .020 or .025 solder, or it will easily spring back no matter how many times you squish it.

 

[Jason628]

Cool, I'll try on the sides with the solder I have. I ran it through several times on front and back using a new piece everytime. I hit a snag with my chain brake. The little detent lever is missing from my kit.

 

[Jason628]

So on the sides I got around .022-.024

 

[Jason628]

Top cover fitment is kinda crappy. Can't get a wrench on the plug. Going to have to modify it a bit.

 

[Wonkydonkey]

Not planning on porting it. I did even out the intake port a little because it looked like doodoo. I'll measure squish again. Did a vacuum test and have a leak. Pretty sure it is the intake manifold to carb flange. It is kind of a poor design. Pretty sure the stihl ring is notched around the bolts and this one is round and protrudes out like it's too big.

I'm not sur if you picked up what was said earlier ? Don’t forget you need the part 17 in the diagram

 

[MustangMike]

Your squish is good, and I have modded a lot of those plug holes so that the wrench fits OK. Need to do it even more when you delete the base gasket.