spudulike

Been cracking on with a few Stihl MS200T/020Ts that I have had kicking around the workshop far too long. People keep asking me if I have any for sale and the answer now is YES:thumbup: Just finished a 2009 saw in good clean condition, the other one in the pic is a few years older and just started on a clean looking 020T.

It is the oil that dictates the oil to fuel ratio and not the equipment as many think, Stihl HP is 50:1 mix for all saws. The 048 is a big slow revving saw and 50:1 is fine in it:thumbup:

One of the seals had deposited its nitrile all over the bearing making it a bit notchy, sprayed carb cleaner on it to soften the grunge and then span it over and oiled it - negligible play and spins sweetly now. Reducing the thickness of the base gasket will up the compression and give the saw some more torque:thumbup: Compare a saw running 135psi and 150psi - that is the difference:biggrin:

As I said - Sphericals:lol:

Started work on a Jonsered 2051, it starts but idle was pretty hit and miss plus the saw won't restart when warm. Compression plummets when warm. A pressure check shows the flywheel seal was shot, letting out enough air that I could feel it coming out:lol: The bearing behind it was tight but flushed them both out and they run just fine now. The piston had been put on the wrong way round by the previous owner so have corrected this and have been tweaking the gasket thickness to get a bit more go out of it!

It sounds lean on the L screw to me - try richening it by turning the L screw 1/4 turn counter clockwise and adjust the idle speed to make it tick over OK. The story of American Market sounds a load of sphericals to me!

The seals are more likely to go than the crank gasket leaking. The clutch side tends to go first but not always. The brake bleeders produce vacuum and is what I use to vacuum test - pretty easy to use. You could use a bicycle pump a balloon and some tube to pressure check and just apply soapy water around the seals - not a great method but may just work for you!

Sounds a bit like a carb set up issue - when you get it going on the fast idle, does the saw....fast idle - race with the chain spinning or is the fast idle setting a bit low? The issue may just be that the carb L screw needs setting by someone who knows what they are doing! The feathering usually means that the saw is running a tad lean - you could try turning the L screw out by 1/4 turn and then adjust the Idle screw to compensate and see how that goes! What colour is the plug after running a while?

It is the pitch or measurement between links - forget the other two, your saw is designed to take 0.325" and will perform faster and more smoothly than any other pitch.

The carb kit would be £10-15 and then just stripping the carb and cleaning it would be another hour, the cleaning materials...... £25 - you do get what you pay for so it would be interesting to see what the guy does for the money!

OK, looks like we are talking about an MS200T, forget the comment about the throttle valve, the mechanism is pretty reliable - the throttle valve is the disc that opens and closes to let the fuel/air vapour through and a sticky throttle can cause the revs to hang on when the throttle is closed. Nothing will work as well as a pressure and vac test to diagnose issues! The MS200T carb has a few issues - the £25 fix may work but have no idea as to what the sellers skills are! The 020T carb is generally a more reliable carb. It would be worth trying a known good carb on the saw!

The running on is a possible sign that the crankcase is pulling in air when in its vacuum state, the items a vac and pressure check will show up are carb inlet manifold leaks, impulse line leaks, cylinder base gasket leaks, decomp leaks, crankcase gasket leaks and crankshaft seal leaks as well as any cracks etc The carb itself can leak air as well but the leak down test should not include this. You should rule out that the throttle valve isn't snapping shut properly - had issues like that before!

Yes, on real bad ones it can be on the inlet side as well! If the transfer isn't fully removed, you run the risk of damaging the rings. If the seize has been bad, it is also worth running a diamond file around the exhaust port to make sure the bevel is clear of aluminium as well. I usually use different grades of wet and dry paper to lightly hone the bore.

Computer keyboards Rich, 20 years in manufacturing and 10 in Sales/Marketing - it is the roots in manufacturing where the mechanical knowledge partially comes from!

The black lines are OK if they are not scores, they appear to be caused by heat and if you can't feel them with your fingertip then the cylinder is OK. You can usually tell if the scores are through the Nikasil as the acid/alkali will fizz along the score if it is through the plating. As long as the bore is smooth, all should be OK - from the pic, it looks like there may possibly be a chip out of the top of the exhaust port???

Full rebuild Rich, it has the 020 carb already, comp at 155psi without any tweaks - just cleaning it up and repalcing parts as necessary! Let me know what gives - should be ready in a week or so!

You are lucky Martin, both parts are the same as my knackered 2165 Jonnie:thumbup:

Oh my, what have I done:blushing: Martin - you need some cheap natural bristle paint brushes to get all that crap off the saw parts - if you are keeping the bearings in place - flush out any crap out of the bearings! Will check out the 2165 I have and compare part numbers. My bench..............just started on one of my MS200Ts - will be up for sale once done:thumbup:

Can you lower the idle to around 2,700rpm? If you have the L screw on one turn out and the revs won't come down, I would suspect an air leak and if it remains unchecked, the next stop is a fried piston:thumbdown: Have you set the WOT at 14,000rpm? and if so, is the screw on turn out? If you are richening the mix beyond the normal 1+1 turns - go very carefully as you are compensating the air leak by richening the fuel system!

I think Rich is reverting to his native Welch.....boyo...theres lovely:blushing:

The ported 357XPs are known as the angry wasps for obvious reasons:thumbup:

That would chafe a bit:lol:

Rich....your saw sounds like that Irish guys 024 a few months back, think he ebayed it in the end after nothing would fix it:001_rolleyes: Good luck with the cooking:thumbup1:

Have you vac and pressure checked it? Splits and some seal problems show up better on pressure check and some seal problems show up on vacuum check only - just depends on what may have failed.

If the carb has been cleaned (thinking of foreign bodies in the gauze filter) then it sounds like you may be getting puddled fuel in the crankcase on idle that is then flooding the engine when the saw is leveled. Try turning the L screw in on idle, when you hit the highest revs, undo it 1/8th of a turn and, when the saw is pretty cold, crank the throttle open and see if it picks up OK, if it bogs, open the L screw up slightly more, if not, leave and adjust the idle for correct idle speed. Try the test again - sounds fuel related and the common issues are crap in the carb, position of the fuel line/filter or the issue I mention above. Airleaks can cause similar issues but will cause soaring in revs on idle and can happen when the saw is on it side - have you pressure AND vac tested this saw, if you have, have you pushed, pulled and rotated the crankshaft when doing it? Another common problem is a hole in the impulse line where it joins the crankcase - the vac and pressure tests can miss this if you are not thorough! The pulling on the top handle at different angles can make the hole open and close causing issues! Good luck Rich:thumbup: