426 first start up after complete rebuild.


6 replies to this topic
  • 84rm250

Posted October 07, 2009 - 09:54 AM

#1

Like it says, i got my bike all back together lastnight and am going to start it today.
I'm kinda worry'd about the first start up because it will be a semi dry start up (only the oil i coated everything in on reassembley) Is there a way around this? Some way to prime the oil system first?
What would be the best way to break it in? New rod kit, piston&rings, and a rebuilt head.
Is there a way to bleed the cooling system? or just fill it and check it after the first warm up??
Any help would be great! Thanks in advance!

  • grayracer513

Posted October 07, 2009 - 11:15 AM

#2

... it will be a semi dry start up (only the oil i coated everything in on reassembley) Is there a way around this? Some way to prime the oil system first?

The 426 oil fill puts the oil in the feed side of the system, so that's not a worry. If you want, you can lay the bike on it's side, remove the oil filter cover, and pour a bit of oil in there to speed up the rise of oil pressure. If you're really concerned about it, pull the spark plug (or use the manual compression release if you have it), loosen the oil manifold at the head, and crank the engine until oil is pumped out at the loose fitting.

What would be the best way to break it in? New rod kit, piston&rings, and a rebuilt head.

Read:
http://www.thumperta...607#post8676607

Is there a way to bleed the cooling system? or just fill it and check it after the first warm up??

Fill it, wait a minute, and refill it, then check after it runs for two minutes (carefully), then again after it runs a while longer.

  • 84rm250

Posted October 07, 2009 - 12:28 PM

#3

thanks for the help gary, but i beleave i have bigger problems now :busted:

while trying to start it just now if feels as if it has very little compression, dont need to use decomp lever at all to kick it over. It back fired once out of the 10 times or so that i kicked it.
timing off? valves miss adjusted? i had the shop rebuild the head and set the valves.. i know i put the rings in right.(how the man. says to) What else could cause this??

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  • 97 Polaris Ultra SPX

Posted October 07, 2009 - 12:36 PM

#4

Check your timing.

  • 84rm250

Posted October 07, 2009 - 01:06 PM

#5

ok, that was my first guess. i'll do this tonight. Anything else that could be wrong? my buddys 250 feels like it has 8 times more compression as my beast.

  • grayracer513

Posted October 07, 2009 - 01:30 PM

#6

Who is Gary?

  • 84rm250

Posted October 07, 2009 - 06:50 PM

#7

Who is Gary?


Sorry, Gray.... Guess i should read what i'v typed before i post it. My bad.





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