Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 5th April 2020, 13:28   #11
vitesse
I really should get out more.......
 
Rover 75 Saloon

Join Date: Jul 2011
Location: Gävle
Posts: 2,515
Thanks: 395
Thanked 823 Times in 652 Posts
Default

Quote:
Originally Posted by Cosmin161 View Post
On another thread i've read that very few kv6es on road have both vis motors working.
While it is true that a lot of KV6s will have non-functioning VIS motors, it is by no means desirable. I offer a free checking service and generally find most owners will have one defective VIS (usually the balance), if unlucky sometimes both. However, functioning VIS motors make a lot of improvement to the engine, one defective motor is often not noticed, but owners who have replaced both motors generally report a noticeable improvement in performance, this is especially true of the weaker 2.0 engine.
Stocktake who has kindly answered your questions also provides a VIS renovation service. His renovated units incorporate many improvements over the original design and will probably outlive your car.

Regards
vitesse is offline   Reply With Quote
Old 7th April 2020, 17:38   #12
Synchromesh
Gets stuck in
 
Rover 75 Saloon

Join Date: Jan 2010
Location: Preston
Posts: 624
Thanks: 50
Thanked 44 Times in 32 Posts
Default

When VIS motors are operated in situ the load of the flap or butterflies reduces the speed of the motor and prevents overrun when the micro switch switches the motor off at the end of travel. If you operate the VIS motors off the car they run so fast that they reach the end of travel and operate the micro switch but they are spinning so fast the cam rotates a bit more than it should and switches the end of travel micro switch back on and the motor carries on spinning. Many years ago I repaired one and operated it off the car and the above happened. I remember having to strip the unit down again to rectify it but I can't remember what I did to rectify it. If I have to run them off the car now I apply some load to the output peg/square hole with my hand to prevent overrun.
Synchromesh is offline   Reply With Quote
Old 7th April 2020, 18:16   #13
stocktake
Vis Whiz
 
stocktake's Avatar
 
Rover 75 2.5 auto Saloon

Join Date: Jun 2007
Location: LEEDS
Posts: 20,582
Thanks: 2,057
Thanked 3,056 Times in 1,621 Posts
Default

Quote:
Originally Posted by Synchromesh View Post
When VIS motors are operated in situ the load of the flap or butterflies reduces the speed of the motor and prevents overrun when the micro switch switches the motor off at the end of travel. If you operate the VIS motors off the car they run so fast that they reach the end of travel and operate the micro switch but they are spinning so fast the cam rotates a bit more than it should and switches the end of travel micro switch back on and the motor carries on spinning. Many years ago I repaired one and operated it off the car and the above happened. I remember having to strip the unit down again to rectify it but I can't remember what I did to rectify it. If I have to run them off the car now I apply some load to the output peg/square hole with my hand to prevent overrun.
Mostly correct but as the power butterflies loosen with age or indeed wear there is a good chance a standard Power Vis motor can over run and the cam then hits both switches at the same time. This renders the Vis useless until stripped and reset. All of my Power Vis motors now incorporate a limiter pin that 100% stops this from happening.
__________________
Dave...



Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident
stocktake is offline   Reply With Quote
Old 9th April 2020, 12:58   #14
Cosmin161
Newbie
 
Rover 75 RJ

Join Date: Apr 2020
Location: Ruseni
Posts: 22
Thanks: 7
Thanked 5 Times in 3 Posts
Default

Hello.
I am sorry for my late reply but i'm working on this car on my spare time.( She had ALL the commun issues )
Thank you for the provided diagram. I checked again the microswitches and they work perfectly yet the motor spins without stopping. I think i will try to check the electrical conector but for now, i am satisfied with the way the engine idles and runs. It took time to make it idle propperly.
Electrically, now i'm left with a high speed radiator fan error code. When i test the fan with my diagnose i can hear the relay clicking but the fan doesn' start.
*The fan starts when the AC is on and requires the fan for cooling.
I read that i have to remove the front bumper to see whats causing the problem there. Will do that.
Someone wanted to scrap the car because he took it to many mechanics but still the car wasn't fixed. Here in Romania vag group cars are very popular but comun issues with vag group cars don't apply to rover cars so i understood why the car wasn' fixed. So i buyed the car (very cheap) from the guy and started working on it and then started to like it. Now it only has the issue with the cooling fan witch i will fix next week.
Other than that everything works.
Thank you.
Cosmin161 is offline   Reply With Quote
Old 9th April 2020, 13:13   #15
Cosmin161
Newbie
 
Rover 75 RJ

Join Date: Apr 2020
Location: Ruseni
Posts: 22
Thanks: 7
Thanked 5 Times in 3 Posts
Default

Quote:
Originally Posted by vitesse View Post
While it is true that a lot of KV6s will have non-functioning VIS motors, it is by no means desirable. I offer a free checking service and generally find most owners will have one defective VIS (usually the balance), if unlucky sometimes both. However, functioning VIS motors make a lot of improvement to the engine, one defective motor is often not noticed, but owners who have replaced both motors generally report a noticeable improvement in performance, this is especially true of the weaker 2.0 engine.
Stocktake who has kindly answered your questions also provides a VIS renovation service. His renovated units incorporate many improvements over the original design and will probably outlive your car.

Regards
True. My car is a 2.0 and had both vis motors broken. I managed to fix the balance one and the improvement was substantial. I don't intend to leave it like this but i don't want to get stucked on this issue. Since the engine works fine, i can fix the rest of the problems, register the car , and then check the power vis again.

Last edited by Cosmin161; 9th April 2020 at 13:18..
Cosmin161 is offline   Reply With Quote
Old 9th April 2020, 13:36   #16
stocktake
Vis Whiz
 
stocktake's Avatar
 
Rover 75 2.5 auto Saloon

Join Date: Jun 2007
Location: LEEDS
Posts: 20,582
Thanks: 2,057
Thanked 3,056 Times in 1,621 Posts
Default

Hi Cosmin,
Thank you for coming back to us and I am sorry you cannot find the fault. Providing the wiring on the car is correct then it can only be the micro switch.
You are correct not to let it stop you getting your car roadworthy, until you can find time to fix this simply leave the Vis motor unplugged.

I have only ever come across this once and that was when the plug that should go to the lamda sensor was inadvertently plugged into the Vis as they were the same plug fitting!!

When you are ready to look again at the Vis motor send me a message and I can tell you the colour of the wires that go to the Vis and what voltage they carry. That said a continuity test of the switches Open and closed) is a must to move forward.

Good luck with the rest of the car.
__________________
Dave...



Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident
stocktake is offline   Reply With Quote
Old 9th April 2020, 13:52   #17
Cosmin161
Newbie
 
Rover 75 RJ

Join Date: Apr 2020
Location: Ruseni
Posts: 22
Thanks: 7
Thanked 5 Times in 3 Posts
Default

Can you please tell me where are these plugs located?
Cosmin161 is offline   Reply With Quote
Old 9th April 2020, 14:20   #18
stocktake
Vis Whiz
 
stocktake's Avatar
 
Rover 75 2.5 auto Saloon

Join Date: Jun 2007
Location: LEEDS
Posts: 20,582
Thanks: 2,057
Thanked 3,056 Times in 1,621 Posts
Default

The plugs go to the sensors in the exhaust one of them is quite close to the vis motors at the back of the engine.
Just to make sure you have the correct plugs fitted to the Vis motors you should have the following colours on the plug.

Power:
1. Orange/Yellow
2. Black
3. Blue/Yellow
4. Blue/Pink

Balance:
1.Grey/Black
2. Blue/Orange
3. Black
4. Blue/Yellow
__________________
Dave...



Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident
stocktake is offline   Reply With Quote
Old 9th April 2020, 18:00   #19
Cosmin161
Newbie
 
Rover 75 RJ

Join Date: Apr 2020
Location: Ruseni
Posts: 22
Thanks: 7
Thanked 5 Times in 3 Posts
Default

Quote:
Originally Posted by stocktake View Post
The plugs go to the sensors in the exhaust one of them is quite close to the vis motors at the back of the engine.
Just to make sure you have the correct plugs fitted to the Vis motors you should have the following colours on the plug.

Power:
1. Orange/Yellow
2. Black
3. Blue/Yellow
4. Blue/Pink

Balance:
1.Grey/Black
2. Blue/Orange
3. Black
4. Blue/Yellow
SO... the VIS plug and the lambda sensor plug were swapped.(I had a o2 sensor error code but I thought this would go away after i drive it around since the car hasn't moved since 2014)
i feel so dumb now ) but i would never thought that the o2 sensor could have the same plug as any other plug on the engine.
NOW.. the power vis does this: With the cam of the gear between the microswitches if I plug in the cable the gear rotates and when it hits the microswitch it stops. But when I test it with the diagnose it doesen't rotate towards the other microswitch.. the balance motor does.
Cosmin161 is offline   Reply With Quote
Old 9th April 2020, 20:04   #20
stocktake
Vis Whiz
 
stocktake's Avatar
 
Rover 75 2.5 auto Saloon

Join Date: Jun 2007
Location: LEEDS
Posts: 20,582
Thanks: 2,057
Thanked 3,056 Times in 1,621 Posts
Default

Cosmin that's great news
Glad I could help.
If your sure the switches are OK then sounds like a dry solder joint or the relay is fried on the Vis
Part No: V23079A1003B301

Good luck with the rest of the car and most of all thanks for coming back to let us know.

Edit, just had a thought, if when you plugged the Vis motor in it is possible the gear over rotates and the cam actually hits both microswitches and then it locks up and will not move as both switches are open. Usually the resistance of the brown arm in the manifold stops this over run. have a quick look
__________________
Dave...



Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident

Last edited by stocktake; 9th April 2020 at 20:10..
stocktake is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 13:54.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd