What's on your bench today?

[Dan Earp]

Dirty.... Lol you must be talking about someone else, i bathe my quarterly lol

[Eddy_t]

357 cylinder cleared of transfer, all shiny and smooth! Now just to wait for parts for everything!

 

 

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[felixthelogchopper]

Cheers mate, you may come to regret that offer.

 

I knew your suggestion would bite you on the bum . When I went to replace a mixture screw after flushing it out with carb cleaner, it went in a couple of turns then felt like it went solid. I didn't want to turn it any further as it felt like it would cause damage. Any suggestions, Rich?

[Rich2484]

I knew your suggestion would bite you on the bum . When I went to replace a mixture screw after flushing it out with carb cleaner, it went in a couple of turns then felt like it went solid. I didn't want to turn it any further as it felt like it would cause damage. Any suggestions, Rich?

 

Hmmm ok. Maybe cross threaded, maybe something got in there. Have you taken it out and checked the end. Should be a nice point. If not then its been crushed, or the thread should be nice. But the screw is steel and the carb ally so the thread may be crossed on the carb more than the screw.

 

A good inspection is required.

[felixthelogchopper]

Hmmm ok. Maybe cross threaded, maybe something got in there. Have you taken it out and checked the end. Should be a nice point. If not then its been crushed, or the thread should be nice. But the screw is steel and the carb ally so the thread may be crossed on the carb more than the screw.

 

A good inspection is required.

 

Cheers, mate. Will have a look on Monday when I'm back in. Maybe a little grease will help it. Other than that hiccup, it all seems to be going back together ok.

[Rich2484]

Cheers, mate. Will have a look on Monday when I'm back in. Maybe a little grease will help it. Other than that hiccup, it all seems to be going back together ok.

 

Ok. Can carefully try another mix screw to see if another one fits ok if its a pita to see the thread. I use magnifying glass to check these.

[mikerecike]

Cheers, mate. Will have a look on Monday when I'm back in. Maybe a little grease will help it. Other than that hiccup, it all seems to be going back together ok.

 

I think grease will create a different set of problems - i wouldn't personally. You sure you haven't mixed the H and L screws up - different thread sizes? - sorry not even sure what you're talking about but I'd steer clear of grease - i use a bit of wd40 after cleaning.

[felixthelogchopper]

I think grease will create a different set of problems - i wouldn't personally. You sure you haven't mixed the H and L screws up - different thread sizes? - sorry not even sure what you're talking about but I'd steer clear of grease - i use a bit of wd40 after cleaning.

 

No, I was careful to only take one bit off at a time. By the way, I haven't forgotten the paperwork I'm sending you.

[mikerecike]

Personally I work from the outside in, there are limitations on what can be done, there is a known SAFE maximum size a port can be widened - too wide and it can cause excessive wear or a snagged ring.

 

You also have limitations caused by where the rings end and by the type and size of piston skirt. There are again known distances a piston MUST cover a port by and distance a ring end must be away from a cylinder opening including the upper transfers.

 

The only work I do from the inside is re modeling the rear transfer and ensuring a smooth bevel on the inside of all modified ports - failure to do this will snag a ring pretty quick as some have found out:thumbdown:

 

There are many ways of looking at this type of work, I get 80% of the gains with the work I do and don't spend all my life trying to get the further 20% with port timing changes, my porting ethic is to increase flow within the cylinder and to improve blowdown and scavanging plus a hike in compression and generally get between 20 & 25% faster cutting speed with the work I do.

 

A recent MS200 came back to me with 190psi with the owner saying it hurt pulling it over - he had busted his wrist earlier though but still nice to see a modded saw having so much compression with a relaively simple mod. Standard MS200 of that age are generally 150psi and a real good one in standard trim - 170psi!

 

Hope that gives you a little insight - don't think it is easy, don't just attack the ports with nothing but hope, look at how wide your piston skirt is, look at where the rings end on the piston and personally would start by widening the exhaust and inlet followed by a muffler mod and then tune the carb based on what the engine is now doing - VERY generally, this will be turning the H screw IN by between 1/8 and 1/4 turn - this is down to the extra venturi effect on the carb caused by the extra flow you have created.

 

And they said it was easy:lol: Oh - and use diamond burrs forr the nikasil plating and HSS ones on large aluminium excavations - HSS or files are bad news on hardend plating!

 

Good luck:thumbup:

 

Cheers Spud that's a lot to think about - really appreciated - Question if you only did the exhaust and not the inlet will there be any gain at all? is it 50:50 in terms of gains - exhaust / inlet?

 

i'll bear this in mind - (was possibly gonna go down the dremel and a bag of hope route):

"don't think it is easy, don't just attack the ports with nothing but hope, look at how wide your piston skirt is, look at where the rings end on the piston and personally would start by widening the exhaust and inlet followed by a muffler mod and then tune the carb based on what the engine is now doing"

[spudulike]

Another ms200t has appeared on my bench. They must be breeding. I knew I should have spererated them.

 

This one is up for a bit of mod. No porting just a squish increase and exhaust mod. Don't see much point in porting as they don't leave much anyway and for a saw that is a working saw the squish and exhaust will be plenty. IMO.

 

Might even look at reducing the bottom of the pot a bit to get that extra bit of squish.

 

How much are you going to take off the bottom Rich, very interested in how much you think you can get away with!