I am posting this for a buddy. He just bought this used Cat. I went ok the
first time out, but he felt the need to clean the carburaters, because of
a little bottom end hesitation. Sometime this past week he was out again
and sensed a slight degrease in power (he figured it was him since he was
riding with two new 670 mxz's) Saturday we checked the carburators again,
when taking it for a little blast in the back yard, it seemed as if the
track was frozen (meaning it wouldn't turn) I lifted the rear off the
ground and it had just enough gumption to spin the track, once you got it
going up to the top end it was alright, but the power wasn't there
So we brought it back inside and took a look. The motor starts one pull,
everytime, alright, twice if it's cold. When first fired, it's fine, two
minutes later, it's back to it's same old tricks. It seems like at a
standstill the motor will not accelerate past the clutch engagement RPM
(~3500 RPM?). With the track up in the air it will, but only slightly
more. It seems to run a little rich also, but the plugs are a nice shade
of brown and there are no score marks on the exaust side of the cylinders.
This is what we have done so far;
1. Dissasembled and cleaned carburators (4 times)
2. Checked to driven clutch to make sure there was enough tension on it,
so it didn't go directly into "high gear".
3. Wiggled all electrical cables and ran it in the dark, looking for arc'ing.
4. Removed the drive belt to see if the motor was capable of higher RPM
without a load (No luck)
5. Checked the Expansion chamber and muffler for a mice nest.
One mechanic he talked to on the phone said it almost sounded like an
inner engine seal. He said on that year sled they had problems with the
motor in general, and this was one of them. Something to do with the gas
mixture no being compressed in each crankcase, because instead of the
mixture getting compressed, it gets forced into the opposite crank
chamber. The test for this would be a leakdown test.
I read a post from someone with a 1980's 440 LC had similar problems and
turned out to be a CDI box. (Something to do with the timing retarding on
acceleration) Does this seem possible?
Could someone with a service manual briefly explain what needs to be
plugged and the amount of pressure used for the leakdown test. Also some
specs, like the advance on timing and the proper compression I should get
with a tester.
Could you cc me in mail on this one if your going to post so I can be sure
not to miss it. If you would like to fax a couple pages from the service
manual, write me and I'll give you my fax number at work.
P.S. FOR SALE! 1994 Artic Cat Cougar 440 LC, see description above ;)