I know this is an older video I am doing alot of research for my Volvo love the car but tons of issues all lights are illuminated on the dash hard cold starts drinks fuel like a V12 and I am not sure what's going on I have checked everything I am beginning to think 🤔 there is a bad ground somewhere cos when I say all dash lights are on they truly are the stereo won't work either has a funny numerical code that is displayed on the LCD screen not sure if the 4WD is working how do I test that? ....also my car doesn't have the Haldex correct? My Volvo is a 2000
i can't help with the electrical issues - maybe just fire the parts cannon at it? Regarding radio - if the battery is disconnected you need to enter a 4-digit pin to 'unlock' the radio. This is an anti theft feature. Regarding the 4wd system - jack up all 4 wheels and see if they spin when it's in gear. If the rear wheels don't spin the system is damaged. Regarding Haldex system - Haldex was introduced in 2003. I don't know which month or VIN # the change happened at. If your car is a 2000 it will have a Viscous Coupling (VC) like this. Hope this helped answer your questions :)
@@sebastianciupinski8973 I don't know if Volvo still make them, but they can be found in any awd Volvo pre 2003, when the haldex system was introduced.
Under conditions where torque is shared on both sides but at different levels itll allow slip. But he wont be able to spin it hard enough or fast enough by hand to make that happen. If he can make them slip by hand its def blown
Prelude Dude is right. The torque I can apply isn't enough to overcome any initial friction in the unit. I believe it also works by heating up (to a point) as it slips, and changing into a thicker state, where it then grips, and cools. As it cools more slip is allowed. This cycle goes back and forth. The coupling also accounts for differences in turning radius between the front and rear tyres, the same way a diff does between left and right.
@@aralez3061 Initial friction? But if it does not allow differential movement not even when stone cold, once you force it to rotate independently then it will get even harder by getting warmer. Even when the fluid is cold it never functions as an open differential. It seems that it always places stress on the driveline in normal city driving with a lot of turns.
@@PrimalMiltos By initial friction I mean the friction that is created when the shaft starts trying to turn. From what I have read and various volvo adverts there is meant to be 5% of torque going through the shaft under normal driving conditions, to decrease response time.
@@aralez3061 Now it makes sense. It's always engaged ever so slightly. They say for example the Express van has 35%-65% F-R torque distribution. Which explains why there is no delay see one here: ua-cam.com/video/JQdroEnlv6I/v-deo.html
I have xc70 2001, its uses same viscous coupling. When I drive in reverse, there is none torque to rear wheels. I tested it on ice, and in reverse, it only rotating front wheels, like a normal fwd car. But driving forward, all wheels spins very good, and all is fine. Is it normal for old xc70 (v70xc) or there is a problem ir viscous coupling? How do you think?
There's a reverse lockout. its to stop the rear wheels driving the prop shaft and to I think helps prevent damage to the grearbox. Mostly applicable under hard braking.
@@aralez3061 thanks. I already welded viscous coupling and freewheel together, and now I have full time AWD. And no problems or damage to gearbox. Also I strengthen the gearbox and bevel gear connecting point.
Thanks for that!
This was quite helpful tone. Thank you.
Glad it was helpful! Thankyou for the feedback :)
I know this is an older video I am doing alot of research for my Volvo love the car but tons of issues all lights are illuminated on the dash hard cold starts drinks fuel like a V12 and I am not sure what's going on I have checked everything I am beginning to think 🤔 there is a bad ground somewhere cos when I say all dash lights are on they truly are the stereo won't work either has a funny numerical code that is displayed on the LCD screen not sure if the 4WD is working how do I test that? ....also my car doesn't have the Haldex correct? My Volvo is a 2000
i can't help with the electrical issues - maybe just fire the parts cannon at it?
Regarding radio - if the battery is disconnected you need to enter a 4-digit pin to 'unlock' the radio. This is an anti theft feature.
Regarding the 4wd system - jack up all 4 wheels and see if they spin when it's in gear. If the rear wheels don't spin the system is damaged.
Regarding Haldex system - Haldex was introduced in 2003. I don't know which month or VIN # the change happened at. If your car is a 2000 it will have a Viscous Coupling (VC) like this.
Hope this helped answer your questions :)
Can those units be rebuilt? Mine binds up in turns occasionally.
As far as I'm aware they can't be rebuilt, and are a fully sealed unit. Opening it would destroy it. How do you know it binds up?
Can i change this vcu oil?
No, it is a sealed unit.
@@aralez3061 yes, but how about drilling a hole with a drill and replacing the oil? Then we can cover it with a bolt
@@aralez3061 ua-cam.com/video/8nDn1rqL_3Y/v-deo.html
@@turgutakdogan15 I guess that could work, but draining the cooked oil my be painful - my understanding is it's quite sludgy.
@@aralez3061 It's a mixothixotropic fluid, not really an "oil."
What's the OEM part number?
Pretty sure it's 9463313.
@@aralez3061 the question is where to get such part...
@@sebastianciupinski8973 I don't know if Volvo still make them, but they can be found in any awd Volvo pre 2003, when the haldex system was introduced.
So the functioning one is acting just like having a solid shaft. Why have viscous coupling if no speed differential is allowed?
Under conditions where torque is shared on both sides but at different levels itll allow slip. But he wont be able to spin it hard enough or fast enough by hand to make that happen. If he can make them slip by hand its def blown
Prelude Dude is right. The torque I can apply isn't enough to overcome any initial friction in the unit. I believe it also works by heating up (to a point) as it slips, and changing into a thicker state, where it then grips, and cools. As it cools more slip is allowed. This cycle goes back and forth.
The coupling also accounts for differences in turning radius between the front and rear tyres, the same way a diff does between left and right.
@@aralez3061 Initial friction? But if it does not allow differential movement not even when stone cold, once you force it to rotate independently then it will get even harder by getting warmer. Even when the fluid is cold it never functions as an open differential. It seems that it always places stress on the driveline in normal city driving with a lot of turns.
@@PrimalMiltos By initial friction I mean the friction that is created when the shaft starts trying to turn. From what I have read and various volvo adverts there is meant to be 5% of torque going through the shaft under normal driving conditions, to decrease response time.
@@aralez3061 Now it makes sense. It's always engaged ever so slightly. They say for example the Express van has 35%-65% F-R torque distribution. Which explains why there is no delay see one here:
ua-cam.com/video/JQdroEnlv6I/v-deo.html
I have xc70 2001, its uses same viscous coupling. When I drive in reverse, there is none torque to rear wheels. I tested it on ice, and in reverse, it only rotating front wheels, like a normal fwd car. But driving forward, all wheels spins very good, and all is fine. Is it normal for old xc70 (v70xc) or there is a problem ir viscous coupling? How do you think?
There's a reverse lockout. its to stop the rear wheels driving the prop shaft and to I think helps prevent damage to the grearbox. Mostly applicable under hard braking.
@@aralez3061 thanks. I already welded viscous coupling and freewheel together, and now I have full time AWD. And no problems or damage to gearbox. Also I strengthen the gearbox and bevel gear connecting point.
@@Kriststtyou have any picture of how everything is done? How did you strengthen the gearbox?
What year Volvo did that come from?
And model, I’m trying to find this exact viscous coupling for my build.
@@eddiealonso6650 This one came from a 2001 P2 XC70.