Balance VIS problem

Shogo10 · 24th May 2010, 11:14

Does the butterfly go back in to the manifold in the open or closed position or does it matter it's just i am trying to line up my worm gear wheel and can't seem to line it all up.
Does anyone have a picture of the proper position of the worm wheel thing?

Steve

chris75 · 24th May 2010, 13:09

lots of previous posts on this . This one may be of help

http://www.the75andztclub.co.uk/foru...ht=balance+vis

Clickernick · 26th May 2010, 21:43

It goes back in the OPEN position, as it is open at engine start up and idle up to about 3,100 rpm.

You may need to 'reset' your bal vis by pluging in vis before attaching to the plenum and activating by turning on the ignition. This will reset a 'good' vis motor to its starting position. Same routine for the power vis too.

rrobson · 26th May 2010, 21:54

Quote:

Originally Posted by Clickernick

It goes back in the OPEN position, as it is open at engine start up and idle up to about 3,100 rpm.

You may need to 'reset' your bal vis by pluging in vis before attaching to the plenum and activating by turning on the ignition. This will reset a 'good' vis motor to its starting position. Same routine for the power vis too.

isnt it closed under normal driving conditions? i thought it opened at around 3000rpm, which allowed air pressure and amount to 'balance' between the two banks

stocktake · 26th May 2010, 22:01

Look on the back of the balance motor just around where the oblong shaft goes through. you will see a 90° arc on the plastic. Then look in the shaft that has the oblong slot in it. You will see a small arrow. As long as the arrow is within the arc then that is correct. When you turn the ign on the VIS will reset to hold the balance flap open at rest

HTH

JohnDotCom · 26th May 2010, 22:16

My ongoing Project is going to need both VIS motors repairing replacing.

Shogo10 · 26th May 2010, 22:27

HI
Thanks for the replies yes i positioned the wheel so the arrow was pointing in the middle of the arc and the butterfly was partialy open. If i remember on the cogged wheel when i replaced the cover, there was a chunky bit of plastic that protruded out from the cogged wheel in the vis, and that was sitting between the 2 white microswitch buttons.
Would that be the correct position?

Steve

Clickernick · 26th May 2010, 22:42

Quote:

Originally Posted by rrobson

isnt it closed under normal driving conditions? i thought it opened at around 3000rpm, which allowed air pressure and amount to 'balance' between the two banks

Fraid not, wrong end of stick!!, always open up to 3000 rpm then closed.

Recently tried my new vis 'off' the plenum, attached to the butterfly (old duff vis still installed!!) and gassed the engine to actually see the butterfly close and then re open as low rpm resumed.

lots of confusion around but this is fact!!

Closes at higher rpm to shorten tract length to increase torque (runs as 2 x 3 cyl engines as regards air intake)
The use of the word 'balance' is a bit vague! Its open or closed, not somewhere inbetween.

Some members find there bal vis open about 5 mm,,, this is a knackered vis!! as the motor has failed due to a stiff butterfly between 5mm and completely closed. Common remedy is to shave the butterfly around the center pivot to 'ease' the operation of the flap, then repair or replace the vis.

Clickernick · 26th May 2010, 22:46

Quote:

Originally Posted by Shogo10

HI
Thanks for the replies yes i positioned the wheel so the arrow was pointing in the middle of the arc and the butterfly was partialy open. If i remember on the cogged wheel when i replaced the cover, there was a chunky bit of plastic that protruded out from the cogged wheel in the vis, and that was sitting between the 2 white microswitch buttons.
Would that be the correct position?

Steve

Thats right, now plug into the loom and activate the ignition and it should reset to the 'home' position which will corespond to an 'open' butterly upon refitting. The drive dog is oblong/rectangular so will only fit one way,, unless you turn the vis upside down in which case it will be impossible to attach to the plenum!!

all the best

rrobson · 26th May 2010, 23:09

thanks for clearing that up, seems a bit backward but nothing to do with these types of components is ever straign forward

sorry for the mini hijack, but when the engine speed increaces under load, the power vis operates obviously operates and opens the butterflies in the manifold, but does the balance stay open, or does it close as the power set open? or do the all stay open untill a set rpm when all close

24th May 2010, 11:14	#1
Shogo10 Newbie Rover 75 2.0 v6 connie SE Join Date: May 2010 Location: Portsmouth Posts: 21 Thanks: 0 Thanked 0 Times in 0 Posts	Balance VIS problem Does the butterfly go back in to the manifold in the open or closed position or does it matter it's just i am trying to line up my worm gear wheel and can't seem to line it all up. Does anyone have a picture of the proper position of the worm wheel thing? Steve

24th May 2010, 13:09	#2
chris75 same car since 2005 2001 Rover 75 2.0 v6 Connoisseur Saloon Join Date: Nov 2006 Location: Ellesmere Port , Cheshire Posts: 3,811 Thanks: 379 Thanked 549 Times in 466 Posts	lots of previous posts on this . This one may be of help http://www.the75andztclub.co.uk/foru...ht=balance+vis __________________ Who said it was simples ?

26th May 2010, 21:43	#3
Clickernick Posted a thing or two Rover 75 Connie SE Tourer Triumph Street Triple R Join Date: Aug 2009 Location: Bletchley, Milton Keynes Posts: 1,163 Thanks: 75 Thanked 91 Times in 65 Posts	It goes back in the OPEN position, as it is open at engine start up and idle up to about 3,100 rpm. You may need to 'reset' your bal vis by pluging in vis before attaching to the plenum and activating by turning on the ignition. This will reset a 'good' vis motor to its starting position. Same routine for the power vis too. __________________ Real walnut interior. Original refurbished Forked Spokes 16” with Michelin Primacy 4 rubber, Pioneer AVH-Z9200DAB double din Wi Fi phone integration. Retrofitted twin front horns. 160 re-map. Revotec fan. Silicone intercooler hoses and ‘O ring’ replacement. Top hose thermostat. New walnut and smokestone steering wheel with cruise upgrade. Brembo Brakes. Ceramic coated rear Exhaust. L/engine mount, Hydramount, Bosch MAF. Focal Access Drivers and Focal Amp.

26th May 2010, 22:01	#5
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,586 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	Look on the back of the balance motor just around where the oblong shaft goes through. you will see a 90° arc on the plastic. Then look in the shaft that has the oblong slot in it. You will see a small arrow. As long as the arrow is within the arc then that is correct. When you turn the ign on the VIS will reset to hold the balance flap open at rest HTH __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident

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26th May 2010, 22:16	#6
JohnDotCom * Rover 75 FaceLift Tourer CDTi 170BHP Auto ConnSE 2005 Model Starlight Silver Join Date: Nov 2006 Location: Abergele Posts: 28,735 Thanks: 0 Thanked 6 Times in 5 Posts	My ongoing Project is going to need both VIS motors repairing replacing.

26th May 2010, 22:27	#7
Shogo10 Newbie Rover 75 2.0 v6 connie SE Join Date: May 2010 Location: Portsmouth Posts: 21 Thanks: 0 Thanked 0 Times in 0 Posts	HI Thanks for the replies yes i positioned the wheel so the arrow was pointing in the middle of the arc and the butterfly was partialy open. If i remember on the cogged wheel when i replaced the cover, there was a chunky bit of plastic that protruded out from the cogged wheel in the vis, and that was sitting between the 2 white microswitch buttons. Would that be the correct position? Steve

26th May 2010, 23:09	#10
rrobson I really should get out more....... 75 tourer cdti, MG ZS 180, nissan terrano & 1.8t rover 25 Join Date: Feb 2010 Location: Pontefract Posts: 2,643 Thanks: 17 Thanked 295 Times in 218 Posts	thanks for clearing that up, seems a bit backward but nothing to do with these types of components is ever straign forward sorry for the mini hijack, but when the engine speed increaces under load, the power vis operates obviously operates and opens the butterflies in the manifold, but does the balance stay open, or does it close as the power set open? or do the all stay open untill a set rpm when all close