Crankcase vent hose- airbox...

[ResidentWarui]

Umm 2 questions.

1. So when I was taking my carbs out tonight I noticed that the crankcase vent hose to the airbox was disconnected... Could this have been a reason I was having so much trouble running my bike?

2. How can the airbox be removed with the carbs still in? I tried doing this as per the VM carb guide just released and there was no way it was gonna happen... Is it because the guide maker has a bigger bike? Mine being a 550 and his being a... 750 or 850 or something.. I ended up loosening the clamps on the engine side and the airbox stuff and wiggling back and forth until it was finally free.

Keep me updated. Rebuild happens this weekend

[Billy Ricks]

The vent hose being disconnected won't hurt anything although it should at least have its own filter. Previous owner was probably just trying to keep blowby from going into the fuel mixture. Can't answer you other question.

[ResidentWarui]

Yea that's what I thought.... Thanks for the reply...

Another thing is my oil level seems to have risen again...

Will that happen if it sits for a while or what? ...it doesn't smell like gas.

[Billy Ricks]

It might rise a bit as oil clears itself off all the internals. Make absolutely sure you don't have a leaky petcock and/or a stuck float.

[ResidentWarui]

Petcock was leaking somewhat. Another strange thing it did was it wouldn't put out any gas while on prime. Except in short spurts... Very strange.

[ptm]

Getting the airbox out is a little different on every model. You've just got to keep wiggleing and making sure it hasn't snagged any wires, and keep removing things until it comes out. On my 750 it's tight, but it does come out. THe 4th or 5th time you do it, it will be easier...

As for the crankcase breather - the crankcase side doesn't care - it just wants to vent, although it may get a little oil on things. On the airbox side, however, it may cause running problems since it is letting additional air into the box. These bike are very sensitive to the airflow through the box. Other more experienced people should be able to verify that or give more specifics about what kind of behavior that would cause. You might also try a forum search. That's probably been discussed before.

[ResidentWarui]

I see... Hopefully with my carbs rebuilt the bike will run well... who knows. The petcock thing is bogus as well.

[jimcor]

Nope, carbs gotta come off first to get the airbox out. At least on my '80 550L.

Crazy isn't it. Get to the cam chain tensioner, pull the carbs. Get to the starter motor, pull the carbs. Break a throttle cable, pull the carbs.

Boring weekend? Pull... 8O 8O 8O NOoooo!

[Jethro]

Petcock was leaking somewhat. Another strange thing it did was it wouldn't put out any gas while on prime. Except in short spurts... Very strange.

Make sure your gas cap vent is clear...

[ResidentWarui]

Nope, carbs gotta come off first to get the airbox out. At least on my '80 550L.

Crazy isn't it. Get to the cam chain tensioner, pull the carbs. Get to the starter motor, pull the carbs. Break a throttle cable, pull the carbs.

Boring weekend? Pull... 8O 8O 8O NOoooo!

Hahaha...I thought so..

Gas cap vent eh? Could that also make it leak sometimes when it's in the on position or is that just the sign of a bad petcock?

[Dink]

To remove the carbs slightly!! more easily. remove the air filter housing from the rear of the plenum chamber,loosen ALL clamps,pull the carb rack rearwards, and remove the boots btween the carbs and the cylinder head. then tilt the carbs forward a little and remove out the left hand side.
I would recommend replacing the vent hose to the plenum chamber, as the spigot on the plenum being disconnected will laow the bike to draw unfiltered air, this may be adding to your rough running.
Dink

[ResidentWarui]

Forgive me for not knowing what the word plenum means... Please explain

Going to work on rebuilding the carbs now....