Author Topic: 440 Invader bog  (Read 4726 times)

0 Members and 1 Guest are viewing this topic.

Kirk750

  • Newbie
  • *
  • Posts: 18
440 Invader bog
« on: March 27, 2017, 07:23:28 AM »
I have a 1981 Invader with a new crank new pistons. Starts and idles well after warming up and I take off it pulls really well but the more I ride it the develops a bog all the way through the power band. Carbs are clean with new orings new float needles and seats. I'm running 150 mains 120 pilots and the needle is in third clip.the carbs have been synced While going down the trail and you hold the throttle in one position it will seem to clear up a little. I originally thought it was a carb problem but now im wondering about timing. I did put a new stator in it at the same time. After riding it and I pull the plugs they are a nice light brown colour. Any advise is appreciated. Thanks.

kawhead

  • Hero Member
  • *****
  • Posts: 524
Re: 440 Invader bog
« Reply #1 on: March 27, 2017, 08:51:09 AM »
imo   not timing.....almost sounds lean   ie; clears up at steady rpm....when fuel flow catches up.....lite tap of choke help?

gixxer6

  • Hero Member
  • *****
  • Posts: 1565
Re: 440 Invader bog
« Reply #2 on: March 27, 2017, 10:09:40 AM »
I agree with kawhead.  Sounds like a lean condition.  Maybe a plugged fuel filter?  Or bad fuel pump? 

mswyka

  • Hero Member
  • *****
  • Posts: 1791
Re: 440 Invader bog
« Reply #3 on: March 27, 2017, 06:01:31 PM »
We have only had two instances where our sleds were boggy.  One turned out to be leakage around the O-rings in the carb bowl and the other turned out to be stuck rings and blow-by.
Intruders:  1978, 1979, 1981 Custom (Pink)
Invaders:   1980 440
Projects:    1981 Invader 440

Kirk750

  • Newbie
  • *
  • Posts: 18
Re: 440 Invader bog
« Reply #4 on: March 28, 2017, 08:01:06 AM »
I haven't tried giving it choke. Fuel filter is clean. Fuel pump would make sense because it seems to clear up at a lower rpm. Snow is done for this year but I was hoping to figure it out and have it ready for next year. Any one know the part number for the fuel pump kit?

Kirk750

  • Newbie
  • *
  • Posts: 18
Re: 440 Invader bog
« Reply #5 on: March 28, 2017, 08:05:07 AM »
The orings in the carbs are new. I put 1.5 needle and seat in because the 1.2 were unavailable. im thinking I'll start with the fuel pump.

gixxer6

  • Hero Member
  • *****
  • Posts: 1565
Re: 440 Invader bog
« Reply #6 on: March 28, 2017, 09:37:52 AM »
LLP 07-417.  Be careful, one of the gaskets in these kits did not get a necessary hole punched in it...  If you don't add the hole, the pump will not work correctly. 

Joel

  • Full Member
  • ***
  • Posts: 170
Re: 440 Invader bog
« Reply #7 on: March 28, 2017, 10:32:14 AM »
Does anyone have pictorial on the fuel pump gasket hole issue?
79 Drifter 440, 79 Invader 440,82 Intruder,81 LTD, 82 LTD x2, 82 GT Prototype,82 Interceptor #519

Kirk750

  • Newbie
  • *
  • Posts: 18
Re: 440 Invader bog
« Reply #8 on: March 28, 2017, 12:56:54 PM »
Thanks to all of you for your help and advise. I will update in the fall when I try the rebuilt pump.

kawhead

  • Hero Member
  • *****
  • Posts: 524
Re: 440 Invader bog
« Reply #9 on: March 28, 2017, 04:28:08 PM »
imo    go back to the 1.2 needle and seat,that helps with rough terrain....imo  95% of the time the used mic n/seats are better than new aftermarket.....used ones may show wear marks,imo they are well lapped[to a degree, not excessive worn], bet I haven't changed 4 or 5 bad ones in 35+ years.i use an outboard fuel tank and primer line to bench test carb overflow/fuel levels

Interceptor398

  • Administrator
  • Hero Member
  • *****
  • Posts: 2057
Re: 440 Invader bog
« Reply #10 on: March 29, 2017, 08:09:30 AM »
Does anyone have pictorial on the fuel pump gasket hole issue?

I took some pictures of the last one I did.  I will be gone for a couple days but will see if I can post them this coming weekend.

gixxer6

  • Hero Member
  • *****
  • Posts: 1565
Re: 440 Invader bog
« Reply #11 on: March 29, 2017, 11:10:30 AM »
I suggest the pictures, a description of the problem, the part number be posted and pinned to the top of the Tech Section. 

jimvw57

  • Hero Member
  • *****
  • Posts: 624
Re: 440 Invader bog
« Reply #12 on: March 30, 2017, 10:31:46 AM »
standard gasket (no hole)


Gasket with hole


Where it fits on the pump


Hope that helps!

Boomologist

  • Administrator
  • Full Member
  • *****
  • Posts: 141
Re: 440 Invader bog
« Reply #13 on: March 31, 2017, 03:04:35 AM »
Jim,
Nice pict's of the fuel pump gasket.
I'm talking with Bob about getting the manuals back online and would like to have your permission to include your pictures of gaskets.
Thanks,
     Boomologist