Thread: Stihl 034 AV Super reconditioning

OEM parts from the US are probably still cheaper than OEM Australia?
eg http://www.baileysonline.com/Chainsa...-Chainsaws.axd

Failing that 3rd party parts also from the US are a good deal.
Meteor pistons have a good rep eg
http://www.baileysonline.com/Chainsa...036-MS-360.axd

Pistons are a lot harder to find but I'd be looking at ebay for these.
If you purchase from someone that deals with a fair few parts and has a good rep you will probably be OK.

This sort of repair will definitely requires a crankcase pressure test.

BobL: thanks for your help,
For the pressure test, is there a commonly available gadget/ method that is used to block off the carby port? Also, I've seen pressurisation through the carb.port and through the impulse line, is one better than the other? It seems the impulse line would be easier as I wouldn't needs to organise a plug with a valve arrangement..?
Cheers, Eo

Originally Posted by OzEo

BobL: thanks for your help,
For the pressure test, is there a commonly available gadget/ method that is used to block off the carby port? Also, I've seen pressurisation through the carb.port and through the impulse line, is one better than the other? It seems the impulse line would be easier as I wouldn't needs to organise a plug with a valve arrangement..?
Cheers, Eo

You can buy Crank Press Test kits but I made my own
Details are here. https://www.woodworkforums.com/showth...341#post920341

Thanks Bob, I'll have a crack

There are some very cheap vacuum/pressure gauges on ebay that would do the trick.

You need the gauge to get up top 6PSI on the pressure side and about 4PSI on the vacuum side

This one is only $12 http://www.ebay.com/itm/0-1-0-5-MPa-...item485ba855f7
You will probably end up paying more for the connectors although you can find them on line as well.

If you want a finer scale then for $28 there is this nice kit.
http://www.ebay.com/itm/Car-Tester-F..._Tools&vxp=mtr

Thanks Bob, you're a mine of information and I really appreciate your help.
If I could trouble you a bit more, re: part 'D' on your home made test rig; could I buy one or need to make one- I can do if necessary but for the sake of convenience...
Also, looking at cylinder kits online, the meteor brand has a compression valve hole. Can I just plug it permanently with a bung? I think that's part 'F' - 14x1 plug as per your picture? There's another brand available - called Hyway which doesn't have the hole, but I'm not so sure about the quality. Any thoughts?
Thanks again, Eo

Originally Posted by OzEo

Thanks Bob, you're a mine of information and I really appreciate your help.
If I could trouble you a bit more, re: part 'D' on your home made test rig; could I buy one or need to make one- I can do if necessary but for the sake of convenience...

I Guess you can buy these from the US. Probably quicker to make one?

Also, looking at cylinder kits online, the meteor brand has a compression valve hole. Can I just plug it permanently with a bung? I think that's part 'F' - 14x1 plug as per your picture? There's another brand available - called Hyway which doesn't have the hole, but I'm not so sure about the quality. Any thoughts?

Yes you can plug it but I would use a bolt rather than a bung. Make sure it doesn't go into the head too far. You should crank the engine around (gently) during part of the pressure test.

I've heard of Hyway buit know nothing about them in terms of quality.

Hi EO

Guess you are aware that the 034 Super piston/barrel are same dimensions as the 036, and as far as I am aware are interchangeable? I had an 034 Super - good saw. From what I remember when I was looking at similar kits, the 036 came with decompressor (hence tapped hole in head) whereas the 034S did not, and this was the only difference between the barrels. I had thought getting decomp would be useful (so was looking for the 036 kit), but since getting a 381 with decomp I changed my mind. I find it easier to start without decomp, tho if the saw floods the decomp does make it easier to purge the cylinder...
Cheers
Si

Hi all, I have a few questions possibly related to this area if I may in relation to the crankcase pressure test,
What can go wrong if it fails the pressure test? I'd guess fuel leaks for one (not running) fuel being forced out (when running), fuel not entering combustion chamber.
Is there a mechanisim/valve to allow air into the tank to replace fuel as it is used?
I ask because I have an issue with my MS250 that is unresolved (since I ran over it) It will run quite fine for 10 or 20 seconds but then seems to starve for fuel, I open the fill cap and away it will go again.
What does the collective think?


Pete

A saw that doe snot get enough fuel will be running too lean. The role that the fuel plays in cooling the P&C on a 2-stroke is very significant, not enough fuel means overheating even to the point of eventually cooking the saw.

Si- yeah I had read about the 034S/036 when checking out all the pros and cons of doing the reco, but was going to ask for confirmation, so thanks for that. You also pretty much confirmed my suspicions about decompression valves too- although I'm open to all advice of course. Still not sure if it's ok to plug the hole, or if I need to get the other cylinder without it..? I can't think why a bung wouldn't be ok really except it might work loose and the saw wouldn't run. I suppose I prefer to get the meteor cylinder with the hole than the other one which I haven't heard of quality wise.

Pete, when I was checking the whole deal out I found a bloke on youtube who has a series of chainsaw vids who was pretty informative about the whole lean/rich mix fuel thing and the various problems that can arise. Name of channel/ bloke is Andy Reynolds.He's an English chainsaw certifier I gather. Pretty poor quality camera and picture but I got a bit out of them. And a bit funny in his own way, definitely not your super organised workshop and so on. And there are heaps of other videos from other people as well. A pretty good resource as it turns out.
Cheers, Eo

Originally Posted by OzEo

Si- yeah I had read about the 034S/036 when checking out all the pros and cons of doing the reco, but was going to ask for confirmation, so thanks for that. You also pretty much confirmed my suspicions about decompression valves too- although I'm open to all advice of course. Still not sure if it's ok to plug the hole, or if I need to get the other cylinder without it..? I can't think why a bung wouldn't be ok really except it might work loose and the saw wouldn't run. I suppose I prefer to get the meteor cylinder with the hole than the other one which I haven't heard of quality wise.

Eo I wasn't sure what you mean by a "bung" and took it to be a cork or something that just jams into the hole. That is a no-no but a cut off bolt firmly screwed into the hole is fine. That's what I did on my 076 when the decamp valve developed a leak.

Bob, no worries, I can see why you'd think a cork might be a bit of a no no- but having said that I've seen some pretty dodgy fixes on machinery that will work for a bit- my dad's a classic for it. Anyway now that I know I can plug it, I'll spend a bit more to get the meteor- assuming the pressure test/ bearings are ok, or it might be more than it's worth/ more than I can handle.

Thanks everyone for your help, and hopefully ill be able to report back with some good news. I believe that photos are required..? )

Two things ...

1. This test is different from a compression test for a car, I suppose?
(As in the type where you screw a gauge into the spark-plug hole and turn over the motor)

2. I have an old 076 and I wouldn't want to be without the decomp valve. Best. Idea. Ever. in my (granted worthless) opinion.


Cheers,
Paul