2005 Yamaha RS Vector Overheated......New problems

[tjcz71]

Well I hope somebody here can help me out a little with this vector. I do a lot of sled repair, and this one is driving me banana's. It sent a stud through the heat exchanger, and pumped all the antifreeze out and ran until it stalled out. (customer ignored temp light) The dip stick and 1 ignition coil melted in place, along with the bottom of the air box nipple going to the stator cover.

Ive replaced the 3 coils and plugs, dip stick, stator, pick-up, thermostat, temp sensor......compression is 150lbs all 3, performed leak down test, all is good. Ive plugged the hole and was able to get the sled running.

It will fire right up when cold, after it runs for 4 or 5 minutes and heats up it will stall out and will not re-start until its cool again......

Any idea's cdi box??? Im lost and have over 15hrs of labor into this sled.


Thank you!

 

[maim]

Did it bleed correctly from the rear bleeder screw with the rear of the sled raised?

 

[tjcz71]

Im not aware of that bleeder screw, however all the heat exchangers are getting warm when its running. Where is that screw located? Thank you

 

[maim]

There is a screw in the rear crossover tube. It should be acessable under the rear exh shroud if I remember correctly.

 

[tjcz71]

Hmm, thanks...looks like a lot of work to remove that shroud, have to remove tank, and handlebars?

 

[maim]

No. You remove the exhaust tip covers and then the centre cover comes off.

 

[tjcz71]

Thanks will try that later this week

 

[smokingcrater]

Im not aware of that bleeder screw, however all the heat exchangers are getting warm when its running. Where is that screw located? Thank you

steam will heat them up just as well as liquid, but it isn't cooling the engine any... Also not impossible the stator is having issues, they can be damaged by the heat, and problems may not show up until the stator is hot. (wires expand, and suddenly short out or no longer make contact.)

 

[tjcz71]

I replaced the stator with a brand new oem one, thinking the same thing, will definitely try the bleed screw, was unaware of that, but all the exchangers get warm when running

 

[grizztracks]

If the engine ran out of coolant and ran until it quit I find it hard to believe there is not internal damage. In most cases overheating causes head gasket issues and without coolant to cool the oil, damage to critical engine components may have occurred.

When hot does the engine roll over easily, have you check compression when hot? Is there spark after it quits?

 

[tjcz71]

Yes there is spark when it quits, and it cranks over the same hot or cold....no water in oil, pulled valve cover to do leak down test, can hear valves open and close with air leaking into intake and exhaust when valves open....no bubbling in coolant.....will try compression test hot. thanks

 

[tjcz71]

Well after doing a leak down test with the engine hot, there is a very slight leak of air into the adjacent cylinders....pulled engine down to remove head, however the head bolts are completely stuck! Already stripped 2. I am assuming the head is severely warped. Any idea how may thousandths the head can be milled? Going to cut frozen head bolts...also, how do I re-time the engine? I marked everything, just want to be sure.
Thanks a million

 

[grizztracks]

Make sure you replace the chain tensioner even if it is the updated tensioner. You can follow this procedure for tensioner replacement and resetting the timing:

http://www.ty4stroke.com/viewtopic.php?t=90826


Maximum warpage allowed is .10 mm (.0039") but I'm not sure how much can be safely taken off. The heads that I've had machined required around .001" shaved to bring them within specs.

 

[tjcz71]

Great, thank you for your help

 

[tjcz71]

I've replaced the head gasket, and the sled is running better, but if I let it idle for too long it stalls out and its very difficult to re-start, if I keep the track in air, on and off the throttle it runs fine....until I let off the throttle, the idle is properly adjusted. One of my other questions is the LCD supposed to light up when you turn the key or only after the engine starts? It seems this problem is electrical....thank you