wr426 starting / timing issue


42 replies to this topic
  • s3v3red

Posted June 08, 2013 - 09:20 AM

#21

well f***, now i have to clear that hole.... lol

  • Do I Care?

Posted June 08, 2013 - 09:31 AM

#22

well f***, now i have to clear that hole.... lol

Yes and if you didn't see my second post here it is...
The timing seems perfect in your pic. Maybe you are 180* out. Remove cams, turn crankshaft counterclockwise one revelution until the ''I'' mark on the rotor is aligned with stationary pointer. Now refit the cams as pictured in your pic.

Can't hurt to try.

  • s3v3red

Posted June 08, 2013 - 11:39 AM

#23

If they aren't 180 out, wouldn't that damage them if I did turn them 180 out?

  • s3v3red

Posted June 08, 2013 - 11:42 AM

#24

I don't know how they could be, I placed my thumb and finger over compression holes (spark plug hole, compression release hole) and they compressed on that stroke.

The piston is at top position.

That is top dead center, correct?

  • Do I Care?

Posted June 08, 2013 - 11:45 AM

#25

If they aren't 180 out, wouldn't that damage them if I did turn them 180 out?

No, the piston will still be at TDC if the ''I'' mark is as mentioned in my last post.

  • s3v3red

Posted June 08, 2013 - 11:46 AM

#26

ok, ill give her a go. Thanks for the help.

  • Do I Care?

Posted June 08, 2013 - 11:50 AM

#27

I don't know how they could be, I placed my thumb and finger over compression holes (spark plug hole, compression release hole) and they compressed on that stroke.

The piston is at top position.

That is top dead center, correct?


That does not tell you 100% whether or not it is on the firing stroke at TDC.
However, you are correct by saying that when the piston is at the top of the stroke, it is at TDC.

  • s3v3red

Posted June 08, 2013 - 12:48 PM

#28

well, it doesn't back fire now. but still refuses to start... Im at such a loss as to what the problem is. The carb has been cleaned, timing set both ways, new fuel, new spark plug, used a timing light to verify firing time...

Edited by s3v3red, June 08, 2013 - 12:49 PM.


  • Do I Care?

Posted June 08, 2013 - 12:53 PM

#29

well, it doesn't back fire now. but still refuses to start... Im at such a loss as to what the problem is. The carb has been cleaned, timing set both ways, new fuel, new spark plug, used a timing light to verify firing time...

If it does not backfire, that is a start, now you need- compression, spark,fuel.
I am thinking that you messed with the carby settings so set it all how it was originally. If you have lost the O-ring from the fuel metering screw in the process, it will not start (at least not until 100 or so kicks).

  • s3v3red

Posted June 08, 2013 - 01:11 PM

#30

the pilot screw 0-ring? no, its still there

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  • Do I Care?

Posted June 08, 2013 - 01:22 PM

#31

First of all- remove carb to check if the AP is working correctly. If it is you should see a nice stream of fuel when the throttle is applied (with fuel in the carb). If not- check that the AP nozzle is not blocked (common) and that the diaphragm is not perished (it will have cracks if bad). There are mods that you can do to this but that is up to you, use the search bar above. See part number 31 in exploded view below.

Check that the float needle valve and float needle are 100% clean! Now- check that your float needle valve 0-ring is not perished by blocking the fuel with the float needle- If it drips, leaks or still flows- replace the O-ring or float needle valve. See part number 24 in exploded view below.

Blow air jets clean and air passage with compressed air or carb cleaner. These supply air flow to the jets. See parts 20 and 23 in exploded view below.

Check that the fuel metering screw 0-ring is intact (if it isn't it will idle high or rev out completely) and the circuit is not blocked . For your info it goes fuel screw, spring, washer, O-ring. See part number 24 in exploded view below.

Now check that the pilot jet is not blocked or varnished and that the pilot circuit is not blocked- Replace if necessary. For your info- if the pilot jet is too small it will have trouble idling and stall easy. In addition it will run best with the choke on and the fuel metering screw past 2.5 turns out. On the other hand- if the pilot jet is too big it will flood with the choke on or stall and or idle high. In addition it will run best at 1~1.5 turns out and or do nothing when the fuel metering screw is turned all the way in (it should stall if correct). See part 21 below.

Check that the leak jet and circuit is not blocked. Some people like to go smaller on this jet by a few sizes to reduce bog off idle. See part number 20 below.

Check that the main jet, main nozzle/emulsion tube circuit is not blocked. For your info- if you are spluttering through high throttle range ie. 3/4 when the throttle is applied , do not have crisp response, backfire when throttle is let off, motor takes time to wind down from 3/4 throttle, you may be running rich. On the other hand- if you are overheating, revving out before peak performance, backfiring when throttle is applied, lacking performance, you may be running lean. See part numbers 17 and 18 below.

Check that the float height is set right- see [color="#22229c"]manual[/color][color="#282828"] for specifications.[/color]
Posted Image

  • slwracing

Posted June 13, 2013 - 03:27 PM

#32

You asked what the cams look like from the rt side, the lobes are almost flat on the top side, I had a 426 that the cam sprocket twisted on the cam, they are pressed on. So after figuring that out my test is this, when bring the kickstarter up to close to TDC it should hold your weight or about 165 lbs ,standing on the kickstarter, if it doesn't the cam timing is off, just don't use the decompression lever to get it over TDC.

  • Thommo_400f

Posted June 13, 2013 - 03:38 PM

#33

They shuold look like this

WR426002.jpg

  • s3v3red

Posted June 14, 2013 - 11:27 AM

#34

IMG_20130614_142525.jpg

Here's how mine look.... they both look high compared to yours.

  • s3v3red

Posted June 14, 2013 - 01:01 PM

#35

Its alive!!! Thank.you for that picture.Saved me hours of frustration.

  • Do I Care?

Posted June 14, 2013 - 04:46 PM

#36

Its alive!!! Thank.you for that picture.Saved me hours of frustration.

Great news!
Did it turn out that it was 180* out or did I make you check for nothing?

  • s3v3red

Posted June 15, 2013 - 06:43 AM

#37

Apparently it was 180 out too.Yes. thank.you all for.your help.

  • s3v3red

Posted June 15, 2013 - 07:40 AM

#38

Time to order some new cams and then.hopefully she.will be reliable.

  • s3v3red

Posted June 15, 2013 - 11:27 AM

#39

Unless there's some way to reset the cams?

  • Do I Care?

Posted June 16, 2013 - 04:35 AM

#40

Apparently it was 180 out too.Yes. thank.you all for.your help.

Glad I wasn't wasting your time and no problems :thumbsup:
Not sure what you are on about resetting the cams?
Enjoy!




 
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