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Old 01-27-2009, 04:33 PM   #11
HYDRAULICYAM
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Hi ...I have a 93 that sounds like yours and I havn't tried to cure it yet....Will warm up with choke on , Bogs and needs a little choke when staring out until warmer ....sputters at an idle and normally stops after 10 seconds when warm . pulled pto plug after parking one day and it was damp ...B8ES in pto side and a B9E plat. in ignition side....I intend to check crank seals tonight with some start aid. and will see about getting a gold plat plug for pto side.
...I bought last fall and have only put 80 km on it since . packing trail and setting ski track for my wife (and me).
....The blowing of of passages in carb sounds good but it is strange how its the pto side ,,normally it runs warmer...
Good luck to both of us..
Ron
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Old 02-22-2009, 08:18 AM   #12
masterblaster2
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Have an '88 and a 94 vk. Both had throttle switch problems. Eliminated switch. As to not idling, does it slowly throttle down till motor just quits from lack of revs or does it just quit when you let go of throttle?
Had to totally rebuild my 94 last winter. Only had 1700km on it and had died twice with previous owner. This was mainly due to lack of oil. The oil metering from the pump is really finicky with oil cable syncing to carb. Mine was getting only the idle mixture of 100/1 at 1/3 to 1/2 throttle. Redid everything including crank bearings on rebuild.
Also got some pro carb cleaner that you dunk disassembled carb into for 12 hours (make sure no plastic or rubber parts go into this) cleaned with spray cleaner and machine starts and idles perfectly.
Has anyone had one of the transmissions on these things apart?
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Old 04-26-2012, 11:10 PM   #13
vkdriver
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I've own a 2009 VK540III and know many other people that own VK's and a hand full of them had bran new VK's and they ALL have the SAME problem. I believe there is some type of design flaw in which CARB ICING CAUSED BY VAPORIZATION OF FUEL during certian condition occurs. I am also a pilot and carb icing caused by fuel vaporization in aircraft carburators is VERY COMMON during moist atmospheric conditions and within a certain temperature range. When it is very cold out -20C or colder, my VK starts and idles fine. If it is +2C or colder my VK will start but will choke itself and I am totally convinced it is carb ice. But if it is warmer than +2C OR if I pre heat my carb using a small heater placed in the engine compartment by the muffler (just because it's a nice place for it to sit) I start my VK without choke and it idles GREAT 100% of the time IF I pre heat the carb. Try it, and you will see.

And if it is between -20C and +2C (approximately) and I don't use a heater, idle is almost impossible 90% of the time once the carb icing develops... first I thought the choke was getting stuck, but once the idle got bad, further use of choke only make it worse so choke was working... once the engine heat warms up the carb and melts the internal icing then idle becomes perfectly normal. It never fails. I've never had any other type of problem with my VK. Other than this one problem, it is a great machine. Simple, strong and big. Good for work.


Anyone believe me?

Last edited by vkdriver; 04-26-2012 at 11:24 PM.
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Old 08-17-2012, 12:31 PM   #14
HYDRAULICYAM
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Update on my idle problem
http://www.acscc.com/forum/index.php...ery&image=3292
If this link works , you will see a skirtless piston which was found
packed into the ports and conn rod....
Discovered someone previously must have used starting aid and
melted the Mag seal and blown the pto seal out and also the
the inspection door to inj pump, and it was not in the sled.
It took about 250km and 3 winters and still didn't stop except I
decided to check the spark plugs and discovered one stuffed with
Almn....It never ceased to run and worked well except idle..lol.
the piston pin had eaten 3/16" into wall as well....
Found a SR540 engine and rebuilt it ,,,seems to run well now !
Tough engine as even the crank bearings were packed in piston
powder and never seized..
Ron
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Old 01-01-2013, 06:59 PM   #15
dieseltrax
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Hi. This may be an old thread but have you thought of disconnecting the TORRS. It's the safety start/idle/cutoff controller on more recent vk540s, kind of like the tether on most other machines. If you press the throttle or the engine revs even a little on it's own the torrs will kick in and shutdown the engine especially on very cold starts. Just in case it's not a mechanical problem.
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