Carb tuning/mods for modded saw?

[masculator]

Put some photos up that explain what you have done and are proposing because I think your terminology is getting lost in translation

I.E. what you call a transfer port and what we are imagining are 2 different things!

 

[Rusty-880]

Gouge in bottom half of cyl, below exhaust port. Don't talk down to me. Wont take it in person from anyone, wont on here either.
I've always played with chevs not so long with two strokes, assumed comp test the same way., Gauge in spark plug hole and crank it?

 

[Rusty-880]

Put some photos up that explain what you have done and are proposing because I think your terminology is getting lost in translation

I.E. what you call a transfer port and what we are imagining are 2 different things!

The extra slot I bored in from intake port. The one where everyone says I've stuffed it. Cant put photos up till tomorrow sorry. Should have gone to bed hr or so ago actualy...

 

[masculator]

Gouge in bottom half of cyl, below exhaust port. Don't talk down to me. Wont take it in person from anyone, wont on here either.
I've always played with chevs not so long with two strokes, assumed comp test the same way., Gauge in spark plug hole and crank it?

I WASN"T talking down to you I am trying to understand what you are saying!!!

you were the one who started throwing insults D&*^head! so don't talk down to me!

If you can post some pics of what you have done and plan on doing we might be able to help you, because as it stands I do not think anyone on here is truly understanding what you have done or are planning on doing!

If you do this we may be able to get up to speed with where you are at, and what you have or haven't done wrong.

 

[Terry Syd]

I just went out and got a look at the tube of 'Cold Weld' - it is made by Permatex. Unfortunately, the temperature rating was on the package and isn't on the tubes. It is around $30 for two 1oz tubes.

I'd like to see a comparison to this stuff and GB Weld. I wasn't able to find a tube of GB Weld in Oz, but I found this stuff and started using it. Anyway, the stuff is great, I'll never go back to using Araldite for even the simplest jobs.

 

[masculator]

I just went out and got a look at the tube of 'Cold Weld' - it is made by Permatex. Unfortunately, the temperature rating was on the package and isn't on the tubes. It is around $30 for two 1oz tubes.

I'd like to see a comparison to this stuff and GB Weld. I wasn't able to find a tube of GB Weld in Oz, but I found this stuff and started using it. Anyway, the stuff is great, I'll never go back to using Araldite for even the simplest jobs.

Permatex is rated to 350f, and doesnt stick as well as the JB weld which is rated to 500+f, JBweld is readily available and ####s all over the permatex cold weld!

 

[Rusty-880]

Thanks for the info everyone. I'll work it out from here based on that. If the thread is going like this with arguing I'll take the good info given and end my posts here.
Thank you

 

[Terry Syd]

Well, then it looks like you just talked him into getting some GB Weld.

 

[masculator]

Thanks for the info everyone. I'll work it out from here based on that. If the thread is going like this with arguing I'll take the good info given and end my posts here.
Thank you

WTF only one arguing was You. if you post some pics so we can understand what you are saying we might be able to help you.

don't mistake the fact that what you have told us confused us and that we need more clarification as an argument cause it isn't! if you want help make yourself clear so that you can get it. show us some Photos and we might have a clearer idea of what you are talking about and be able to advise you better!

 

[Rusty-880]

Your cr%p from post #15 on. Don't matter if you don't agree, I don't want to get cranky on here so finishing this before I do.

 

[masculator]

Your cr%p from post #15 on. Don't matter if you don't agree, I don't want to get cranky on here so finishing this before I do.

Pardon me? you threw insults at me after I asked you to clarify what you were saying so that I could help YOU!

If you want help then clarify what you are talking about don't tell me I have been trying to start an argument! I asked for you to clarify what you were saying cause what you were saying didn't add up!

If you want help then keep the post going and If I can help or be bothered to from this point on I will!

 

[AUSSIE1]

He obviously means "combustion chamber". Not hard to work that one out.

The reason he is getting low readings is because he is using an auto comp gauge. My Ryco will give similar readings. You need a comp gauge with the valve in the end at the fitting. Supercheap etc have these.

Rusty, post some pics when you can.

 

[mtngun]

assumed comp test the same way., Gauge in spark plug hole and crank it?

with throttle at least part way open. Either lock the throttle open, or set choke lever on fast idle. As Aussie1 pointed out, gauge must have a check valve (white schrader) at end of hose, not all gauges do.

Took .032" off the spare cylinder, kept tripping decomp valve by half stroke on a pullstart and only gave 135psi.

Is this a different 880 cylinder ? Exactly where did you take off the 0.032" ?

Pics would help on the jug(s).

 

[splitpost]

Aussie you beat me to it,Yeah Rusty sounds like that comp tester you got is giving you low readings,can you please post some pics of your cyl mods .......chris

 

[AUSSIE1]

If Rusty is getting 135 psi after machining 32 thou off the base and it's tripping the decomp, I think he will be surprised by the reading from the correct gauge!

 

[Rusty-880]

I'll look at different comp tester. Gota do some work this morn, post some pics at lunch.

 

[mtngun]

If Rusty is getting 135 psi after machining 32 thou off the base and it's tripping the decomp, I think he will be surprised by the reading from the correct gauge!

How do you machine 32 thou off the base without machining a pop-up piston, too ? Unless it had 52 thou squish to start with, not likely for a Stihl.

It doesn't take much to trip a Stihl decomp.

This thread is like a guessing game. Rusty gives us a few bits of information, and then we take turns guessing what he is talking about. :msp_rolleyes:

 

[AUSSIE1]

How do you machine 32 thou off the base without machining a pop-up piston, too ? Unless it had 52 thou squish to start with, not likely for a Stihl.

It doesn't take much to trip a Stihl decomp.

This thread is like a guessing game. Rusty gives us a few bits of information, and then we take turns guessing what he is talking about. :msp_rolleyes:

Fair enough!

 

[Rusty-880]

Considering my original question was about tuning I didn't have pics organised.
Post some in a min.
With any minor mods to the saw it has always been difficult/ impossible to tune easily or correctly. Runs to rich at full revs with only L screw set so it will idle.

Found this in old two stroke book;
"The single difficulty with pressure pulse caburetors is that they are extremely sensitive to both cylinder displacement and crankcase compression ratios, working well only on engines for which they are specifically designed"

If mods make it flow and scavenge better wouldn't the carb need recalibrating to work with differences in pulse pressure?

 

[Rusty-880]

Couple more to come