Advice setting up an 090

[av8or3]

The service manual says max off load engine speed is 8000 rpm. I set it to that on a warm saw and I get 6800 rpms in the cut. Saw cuts really slow at that speed. However....
if I tunes it to around 8000 rpms in the cut it cuts much faster and smoother.
I’ve also diagnosed an (intermittent) air leak on this saw one or both of the oil seals.
Seals are on order and saw runs steady if I start slow . If I piss rev it and drop it in the wood sometimes it will rev to 9200 in the cut ,stay there and just blast thru the log. I’ve leaked checked it, it leaks.
Once repaired , which is best way to tune it?

 

[jmester]

Those have a air vane governor. On the flywheel side. Service manual says set to 11,000 rpm with the governor defeated. The governor should come in at 8,000rpm

 

[Deets066]

Do a little grinding on that vane governor and it won’t drop it so low. Then you can tune it regularly.

 

[Sawrain]

090 I am working on now is 11,000rpm at 1 turn out on the H, no Governor, No chain.

Spec is with chain, just didn’t happen to have it on when checking it this time.

 

[av8or3]

Those have a air vane governor. On the flywheel side. Service manual says set to 11,000 rpm with the governor defeated. The governor should come in at 8,000rpm

I just haven’t read far enough into it yet. Thanks!

 

[av8or3]

Do a little grinding on that vane governor and it won’t drop it so low. Then you can tune it regularly.

Sounds like a plan. Thank you.

 

[av8or3]

Thanks all, I think I’m on the road to success now!

 

[rogue60]

Just winedup the governor spring a few more times so it disables it then tune like any saw. That's the 1st thing all the old loggers did with there 090's.
An ms170 will out cut an 090 with it's governor still operational lol

 

[rogue60]

Got mine out for a run not long ago been sitting a few years.

 

[Absolution]

I got mine off the shelf the other day. I stopped using it because the new west cylinder I had bought I'm pretty sure has some messed up port timing and was near impossible to start.

Which is sad because at the time I bought it was supposed to be the best aftermarket cylinders and over all it looked perfect.

I put the 070 jug back on it (I have 090 clutch installed) and it runs great again.

When I used to mill with it I had the governor just disabled in general still do. Although it's gonna stay on the shelf. Well it's going to be under bench before I get the ladder out to put it back on shelf.


Edit: the jug.

 

[av8or3]

I got mine off the shelf the other day. I stopped using it because the new west cylinder I had bought I'm pretty sure has some messed up port timing and was near impossible to start.

Which is sad because at the time I bought it was supposed to be the best aftermarket cylinders and over all it looked perfect.

I put the 070 jug back on it (I have 090 clutch installed) and it runs great again.

When I used to mill with it I had the governor just disabled in general still do. Although it's gonna stay on the shelf. Well it's going to be under bench before I get the ladder out to put it back on shelf.
View attachment 288844

Edit: the jug.

View attachment 288845

It looks like that’s how this one will be run. I could not get the governor to come up at the right rpm.
I eventually wound the spring so tight it effectively disabled it. Could not find the sweet spot. Tuned the saw with a tach to 11k and it cuts at 8500 or about
It will four stroke at will, just lift it out of the cut. I think it’s fine.

 

[Absolution]

View attachment 288867
It looks like that’s how this one will be run. I could not get the governor to come up at the right rpm.
I eventually wound the spring so tight it effectively disabled it. Could not find the sweet spot. Tuned the saw with a tach to 11k and it cuts at 8500 or about
It will four stroke at will, just lift it out of the cut. I think it’s fine.

I'm jealous of the AV lol.

 

[av8or3]

I'm jealous of the AV lol.

It is nice for sure. Machine vibrates like crazy in use.
I’m interested to know what you tuned your machine to and what speed it held in the cut. I’ve actually tuned this one a bit rich to 10,400 and it still holds 9500 in the cut.
I may have to revisit the governor.