Arctic Cat update

[scottessex]

So far I have not melted anything on the arctic cat, after 3 sets of pistons,
I can rebuild the top end in my sleep!
The last go round I re jetted extra fat, and I retarded the timing 7* for a total advance of 18*btdc.
Right now the water temps re 125-130*
EGTs are around 900* (a tad cool on purpose)
power is reduced by the timing I can tell, I had to take one degree of pitch out of the prop, but the engine is running very smooth and stable.
I have around 1.5 flight hours on the engine this time, a couple more hours of staying close to the runway, and I might venture off over some hay fields.
so far so good. keep your fingers crossed.

[Friendly]

I hope you whip that sucker inline!!! thanks for the update.

[Earthboundmisft]

Scott, good job man. Now that Im flyin, I can say I have experienced the constant concern about an engine out. It is on my mind more than I would like. Keep a tuned ear for a change in tone, your first clue.

[GrantR]

Keep a tuned ear for a change in tone, your first clue.

Not really. I think when Scott's 582 seized there was no warning. It seized hard enough to tweek the crank. Sort of like when you runover a stump with your mower and it suddenly stops!

[scottessex]

Exactly Grant, kinda like I hit some bad air or something.

[All_In]

Good news Scott, we all hope you got it this time. Keep us informed!

[RotoPlane]

It is surely sounding good to go. Oh, Scott.....don't forget to PM me on what my one piston expense share is.....you have probably saved me many headaches!

[pwongkit]

Hi Scott ...What model of the Arctic Cat that you are talking about? I got one the model is 1998 Arctic Cat ZR 600 EFI L/C cool Do you think OK for the gyro power?
pwongkit

[Passin' Thru]

Originally Posted by RotoPlane

It is surely sounding good to go. Oh, Scott.....don't forget to PM me on what my one piston expense share is.....you have probably saved me many headaches!

And I committed for the other one. We're all pullin' fo' ya!

[pwongkit]

Scott...any update for the Arctic Cat engine?
pwongkit

[scottessex]

No update this weekend, I was out of town.
The engine is a 1991 530 from a mountain cat EXT single pipe.

[scottessex]

UPDATE!
So far so good, engine has been running fine, no problems.
BUT since I cannot leave anything alone. I had a brand new
Hirth muffler assy, so I made brackets and straps, and mounted the Hirth exhaust just to see how it worked.
No difference in EGT temps or RPMs, It DID flatten the torque curve, seems to start building power around 4k rpm instead of 5k. also not near as peaky on the pipe.
I think I will stick with the hirth muffler, as it is quite a bit lighter, and smaller too.
Now to dial in the jetting, I am still running slightly rich on purpose.
I'll post pics later.

[All_In]

That is good news Scott!!!

[Friendly]

What are the hours on the engine now Scott?

[scottessex]

This is where it gets sad....... I only have about 4 hours on the engine, most of the flights have been 10-15 minutes. I'll stay over the strip just in case.....then land and check everything over to make sure nothing has loosened up etc.

The last 3-4 weeks have been extremely busy and hectic here, have not had too much time to fly,
Nothing planned for this weekend, so I might get an early morning flight in, Plan to venture out some, if nothing else just to put more time on it.
I did end up changing the Radiator, prop, exhaust, etc, I think I have it where it is going to stay now.
everything has been consistent so far as water temp, EGT, etc. no hickups.
I should be like Mike (earthbound misfit) and should have 40 hours on it by now, but it just has not worked out that way.