What's on your bench today?

[GardenKit]

Comp is good,

Sent from my GT-S5690 using Tapatalk 2

 

Not being funny, but how do you know the compression is good?

 

Just pulling the rope does not give an indication of compression as these engines are fitted with a valve lifter (decompressor)

 

The most you will generate from a vigorous pull (1000rpm minimum) is 110-120psi, which is quite low.

 

The actual working pressure needs to be around 150psi, but you cant measure it unless the valve lifter is broken.

 

Valve clearances are critical to the operation of these engines too, so worth checking.

[spudulike]

I got myself a non running BR600 cheap at an auction. It wasnt running because the fuel line was not connected. Anyway, i can get it started now but it only runs for a couple if seconds before stopping. The plug look past it so i will replace that but not convinced thats the problem. So was think sonic clean on the carb. Its a 4mix which i'm not that familier with. Any top tips.

 

Many thanks Mark

 

Sent from my GT-S5690 using Tapatalk 2

 

Any top tips....yes....sell it on ebay and buy a two stroke:lol: The four stroke Stihl engines are the spawn of satan!

 

If you haven't worked on them before...good luck - I did once and wish I hadn't!

 

Listen to Barrie - he knows a bit about these.....suspect (thats me being polite).....engines.

[fen01]

Not being funny, but how do you know the compression is good?

 

Just pulling the rope does not give an indication of compression as these engines are fitted with a valve lifter (decompressor)

 

The most you will generate from a vigorous pull (1000rpm minimum) is 110-120psi, which is quite low.

 

The actual working pressure needs to be around 150psi, but you cant measure it unless the valve lifter is broken.

 

Valve clearances are critical to the operation of these engines too, so worth checking.

 

After reading that not sure about comp either:o I get feeling this may be a learning experience (meaning pita)

 

Sent from my GT-S5690 using Tapatalk 2

[Ray1]

The 4 mix engines ain't that bad, if you do strip it down and remove the valves and associated parts always keep them as a set, inlet side and exhaust side. Valve, spring, cleat, spacer, nut, push rod, rocker arm and cam follower dont mix them up. When rebuilding dont forget to line the timing arrows up on the cam with the marks on the cylinder before re-sealing the cam cover.

 

Regular maintainence on these engines is essential, and i would reccomend more frequent than they state at every 200 hours.

[GardenKit]

On the subject of compression.

 

A new customer, local guy, came in with a Huskie 262. "stopped mid cut" he says.

 

"Just been somewhere else and had a new 'electric box'" (guess he meant coil)

 

" not much wrong, got good compression" he says.

 

It was quite hard to pull, and would not 'drop', but I tested it anyway. 80psi!

 

Pulled off the exhaust, and sure enough, there was a very scored piston. Lean seize I suspect.

 

The resistance that he thought was compression was in fact the piston scraping up and down.

 

Proper testing is essential IMO.

[fen01]

Cheers guys useful stuff:)

 

Like the story about comp! Just goes to show the difference between an engineer and someone who repairs 'off a menu'. there is no replacement for experience and logical problem solving.

 

Sent from my GT-S5690 using Tapatalk 2

[Rich2484]

Well how's this for service.

 

Ordered a new meteor piston for the 200t on Friday night. After hours, about 6 ish. It has turned up the morning.

 

Will update later after its fitted.

[Ray1]

 

Will update later after its fitted.

 

Fingers crossed it solves the problem.

[GardenKit]

Richard loves a chellenge.

 

Glad its not on my bench though.

[spudulike]

Richard loves a chellenge.

 

Glad its not on my bench though.

 

Fingers crossed it won't end up on mine either - go to it Rich, legs arms and fingers crossed - you can rebuild it - Can he fix it....YES he can:blushing:

 

Just ported, muffler modded and lowered the squish on an MS200t - 180psi - not too shabby:thumbup: Reckon it will be a bit of a weapon when done!

 

Had an issue on pickup - bunged the carb in the new US cleaner and the welch plug fell out - wonder why it didn't run well:001_rolleyes:

 

So Rich, mine is fixed and yours..........