What's on your bench today?

[spudulike]

Got the 200t back together. Nearly. Enough to run it up. Just need some clutch springs (BARRIE).

 

Started good and comp is at 160psi.

 

This is after replacing the crank and bearings with another.

 

Got a technical question. What is the wear limit on the crank bearings area. The old crank looks ok but not sure what the limit is for it. The bearings are shot though.

 

I don't have any spec info although the saws have a little play on the bearings down to the type of bearing and the one on the clutch side is generally the first to go.

 

These saws often knock a little on idle on well used saws but doesn't give issues until thye really get bad!

[Rich2484]

Ok cheers spud. The saw was in bits when I got it so don't know if its any good. Guess I wil get some bearings and seals and see what happens.

[spudulike]

How do you go about muffler modding?

 

Read on here to measure exhaust port and make it no larger than 80%

 

Does it mean measure exh port on cylinder or the port on the exhaust....

 

Might be best to get advice from the beginning

 

Also how do you set the carb after... just a 1/4 turn on the H or do you have to adjust both?

 

Have a few candidates... 064,044,024

 

There is lots of talk on the size of the outlet, there is mention of 80% of the area of the exhaust port on the clinder bore side but some say it really doesn't matter.

 

On the carb - lots of misguided info on this - I have yet to find a ported or muffler moded saw that actually needs richening - the extra flow in the carb draws extra fuel and it will need leaning off IMO

[burrell_]

i can tell u what will be on the spud bench tomorrow

WALKERS crisps :lol::lol:

a 046 ms 200t 372 crank and fly wheel carbs and al sorts of wounderfull things i give him

and payment is still cake

[spudulike]

i can tell u what will be on the spud bench tomorrow

WALKERS crisps :lol::lol:

a 046 ms 200t 372 crank and fly wheel carbs and al sorts of wounderfull things i give him

and payment is still cake

 

Yeah but what type of cake:lol:

[burrell_]

i will get something to keep the misses sweet as she puts up with me :lol:

and for u home made cake :lol:

[spudulike]

i will get something to keep the misses sweet as she puts up with me :lol:

and for u home made cake :lol:

 

I think you will be wearing your tea if she reads this:blushing:

[burrell_]

u bring the wost out of me

[mikerecike]

Testing a coil

Have this Mcculloch on the bench was running fine then spark became nothing more than a very weak tingle on the fingers - with either recoil or turning engine over with drill.

 

Noticed also that the flywheel fins have gone for a burton - no idea how that happened - pulled about a kilo of dirt out of the flywheel side cover. Wonder if overheating can damage the coil?

 

ALSO - Can you test a coil with just a multimeter? If so what's the process ? If not what machine (apart from my finger tips and arm getting a belt) can definitively test a coil?

 

 

 

 

Coil is a 219848-01 Mcculloch

 

Cheers chaps

[GardenKit]

Testing a coil

Have this Mcculloch on the bench was running fine then spark became nothing more than a very weak tingle on the fingers - with either recoil or turning engine over with drill.

 

Noticed also that the flywheel fins have gone for a burton - no idea how that happened - pulled about a kilo of dirt out of the flywheel side cover. Wonder if overheating can damage the coil?

 

ALSO - Can you test a coil with just a multimeter? If so what's the process ? If not what machine (apart from my finger tips and arm getting a belt) can definitively test a coil?

 

 

 

 

Coil is a 219848-01 Mcculloch

 

Cheers chaps

You can test the coil with a multimeter set to Ohms. There are 2 coils within the module.

The Primary coil which has only a few windings should have a low resistance, probably around .7Kohm (general figure, but coils do vary) and is tested between the little connector that the kill wire fits to, and the main body.

The Secondary coil has very many windings of fine insulated wire and should (general figures again) read around 7-10Kohms between the spark plug terminal and the main body.

 

Figures well outside of these could well indicate a duff coil, but I have had many coils with good readings that still wont produce a strong enough spark, so I seldom use a resistance test.

 

I prefer to use a spark tester. many cheap testers just test for a spark, but cannot test for a good spark. An ordinary spark plug can be used in its std form, but unless the coil is very weak it will show a spark. If you open the gap really wide, or even remove the tag it will make it much more difficult for the coil to make a spark, so if one can jump a big gap it must be quite good.

 

Or you can use a fancy tester such as the one below.

 

Coils can produce a spark when cold, but fail when hot. If testing resistance you can do it hot and cold for comparison. A failing coil can also upset timing, causing all sorts of weird symptoms