What's on your bench today?

[geoff]

Again I agree Spud.

By the way,how do you feel about porting & sorting a little echo 26cc top handle?

[Rich2484]

Cheers Rich, I think we have solved many members saw problems and that is what the site is about, always glad to help and any waifs and strays end up on the bench and sorted.

 

Good mix on the site now and makes it a good place to discuss issues and get good advice and that includes your input of course:thumbup:

 

Ha I know nothing in comparison to you two. But I'm learning every time I see the work you do.

[GardenKit]

Thanks Rich, its kind of satisfying when we are able to help someone sort out their problems, and more than a little frustrating when we can't.

 

I do this sort of thing on the bench, day in and day out, so that it becomes sort of automatic, but when trying to sort things on the forum it is different.

 

Firstly we have to understand the problem as written by the arbtalker. Then we have to communicate the answer, or ask further questions.

 

This is where Spud excels. Besides his thorough understanding of the products he has the ability to compile clear and concise instructions. I have tried this but find it a little difficult, so on the whole I leave it to Steve because he is the master especially with saws.

 

Every now and then a topic appears where I say to myself "I can answer this!!" so I jump in.

 

Its a good forum.

There are many very knowledgeable members.

There are many inspirational characters.

There are those who talk nothing but nonsense, but also those who talk common sense.

 

I enjoy it immensely.

 

Thanks once again to Spud for this thread, and of course to Steve Bullman for the forum, as well as to all the Arbtalkers, without them there would be no forum.

[Rich2484]

Don't be too quick to put yourself down on the description part gardenkit. You can do it well enough to get the point through. And to get it understood enough to work with.

 

Although there is one question been bugging me lately and that to port or not to port? What is the pros and cons of porting a saw. Does it shorten the life of the saw? Why do it? And how do you know how much to take away? Is it like polishing a cylinder head inlet outlet ports? Does it add more hp to the saws engine?

Edited October 5, 2012 by Rich2484

[GardenKit]

Anyway, anyway,anyway, back to the thread title.....

 

On my bench today were

 

Tanaka long reach HT for full service and sharpen

 

Stihl FS55 thing, full of old, gummy fuel. Cleaned Zama in U.S. for 45 minutes, rebuilt with new diaphragms etc and hey presto!!...rubbish. Fitted new replacement Walbro and off she went..perfect.

 

John Deere Ride On for starting problems, simple solenoid replacement.

 

200t for full service and new brake handle.

 

Hayter Ranger mower for full service and new gearbox.

 

A couple of new chains fitted, a couple of sales, so a couple of PDI,s. 3 pairs of shears sharpened.

 

6 cups of tea drank, and an hour spent chatting to an old friend.

 

John Deere delivered back and another collected. Quite a quiet day compared with the last 6 months.

Edited October 5, 2012 by GardenKit

[GardenKit]

Don't be too quick to put yourself down on the description part gardenkit. You can do it well enough to get the point through. And to get it understood enough to work with.

 

Although there is one question been bugging me lately and that to port or not to port? What is the pros and cons of porting a saw. Does it shorten the life of the saw? Why do it? And how do you know how much to take away? Is it like polishing a cylinder head inlet outlet ports? Does it add more hp to the saws engine?

I am honestly not into porting. I don't see the need. But I respect those, like Spud, who do. So he's the man.

[Rich2484]

Sorry I should have said it. I was just throwing the questions out there to anyone able to answer some of them. Wasn't directly aimed your way gardenkit.

 

What are the j.d mowers like? We've got two roller drive garden mowers and we havnt used them yet. My thinking was j.d wouldn't put there name to any old crap.

[GardenKit]

Sorry I should have said it. I was just throwing the questions out there to anyone able to answer some of them. Wasn't directly aimed your way gardenkit.

 

What are the j.d mowers like? We've got two roller drive garden mowers and we havnt used them yet. My thinking was j.d wouldn't put there name to any old crap.

IMO the JD R series are unbeatable in the 43cm and 47cm models,both 4 wheeler and rollers, every bit as good as the KAAZ but cheaper.

 

The 54cm 4 wheelers are also brilliant.

 

I have sold quite a few of the 54cm roller models but its not quite as good as it should be in the transmission area. I will now only sell this big one to domestic users and will be selling KAAZ to heavy users.

 

BTW, JD dont just put their name to the SABO mowers, they own the SABO factory.

[Rich2484]

IMO the JD R series are unbeatable in the 43cm and 47cm models,both 4 wheeler and rollers, every bit as good as the KAAZ but cheaper.

 

The 54cm 4 wheelers are also brilliant.

 

I have sold quite a few of the 54cm roller models but its not quite as good as it should be in the transmission area. I will now only sell this big one to domestic users and will be selling KAAZ to heavy users.

 

BTW, JD dont just put their name to the SABO mowers, they own the SABO factory.

 

Learn something new every day

[spudulike]

A brief description of porting: -

 

What you are doing is increasing the flow of gasses through the engine, this in turn increases the venturi effect on the carb pulling in more fuel without adjusting the H screw.

 

The above has the effect of making the saw fourstroke more heavily at manufacturers maximum revs and allows you to run the saw at higher revs than would otherwise be achieveable on a standard machine.

 

The compression is raised by lowering the squish - distance between the combustion chamber and the piston by either removal of the base gasket, fitting a custom gasket or machining what we call a "pop up piston".

 

Port timing can be adjusted by raising the height of transfers and exhaust port and lowering the inlet port but generally I widen the ports and re-model the lower and upper transfers. There are constraints on the amount you widen ports such as the type of piston, ring end position and skirt width on open port pistons (windowed) and the size of the bore - this is where you need to be damn carefull!

 

Open the lower transfers out too much and the transfer velocity will be effected - it is all a balancing act!

 

Also windowed pistons can be opened up to increase transfer velocity!

 

Each element adds a little more and has the effect of allowing the saw to rev higher and hold higher chain speed in the cut.

 

The 357 is something I have really played with, typically they may run at around 14Krpm, the one I did for Burrell fourstroked very heavily at that speed and was giving a good coloured plug and about right at around 15Krpm. A standard machine may well fry at that and also the plug would be bleached white by the lean mix.

 

Once you have run a ported saw, it becomes a need - I have used standard saws bigger than my own and thought - is that it:confused1:, you get used to the wailing and blitz of chip and noise:thumbup:

 

The last thing is going up a pin on the sprocket and fitting a short bar - that gets really fun!

 

Hope that explains a bit!