DIY VCU service

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Sounds good to me. Once you get into it, It's really not that complicated just messy..I wouldn't bother with the bleed nipples I couldn't get the fluid to flow through the gun very well. It just made a even bigger mess. I used a big syringe instead...suck the fluid up and then inject into the hole, occasionally turning the vcu as you go.

I think I used the 30k fluid in mine...but mine is quite slack which is what I wanted...so a 60k should be fine....I would guess a 100k fluid is around stock vcu spec?.

You could just remove some of the old fluid until your vcu frees up a tad and see how it goes from there?
 
Having read through this thread, would a suitable DIY guide be:

1. Drill 10mm holes on opposite sides of the VCU 180deg apart.
2. Allow fluid to drain, helped by compressed air/solvent/heat.
3. Ensure VCU can be turned by hand.
4. Tap and plug bottom hole.
5. Refill with 60,000 cst siloxane - 160ml?
6. Tap and fit plug or grease nipple to top hole.
7. Test VCU on bench - ensure it turns slowly with breaker bar but resists rapid rotation. Adjust fluid volume as necessary.
8. With VCU fitted, do 1 wheel up test.

I can understand exactly what you mean by point 7 and its a great description - but it would be great to have some figures to test against. Not sure if there are any floating around.
 
where are the figures?

its the same as the wheel-up test, just off the car.

How many peeps want to dismantle there car on a regular basis to check the VCU - thats why the wheel up test was invented. Just very few bother to post results.
 
where are the figures?

its the same as the wheel-up test, just off the car.

How many peeps want to dismantle there car on a regular basis to check the VCU - thats why the wheel up test was invented. Just very few bother to post results.

Um, did you watch the video? Length of lever 780mm, weight 7kg. It seems to have been shot in real time so there's your timescale.

No, not many would want to remove the VCU for testing. My point was, in the context of rebuilding one, that the video might be a guide to whether the job was successful.
 
Your all getting too anal about figures amounts etc......I was the same to be honest. No one could give me a straight answer, so I bit the bullet and when for it..what is there to lose when the vcu is fooked anyway.

Drill the bloody holes empty the old fluid refill until you are happy plug the holes fit to car and enjoy.

I was going to do tests and figures but in the end I could not be arsed...Just wanted the hippo back in 4x4 mode for winter.

You can sit there waiting for facts and figures or just do it . Job done!
 
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Your all getting too anal about figures amounts etc......I was the same to be honest. No one could give me a straight answer, so I bit the bullet and when for it..what is there to lose when the vcu is fooked anyway.

Drill the bloody holes empty the old fluid refill until you are happy plug the holes fit to car and enjoy.

I was going to do tests and figures but in the end I could not be arsed...Just wanted the hippo back in 4x4 mode for winter.

You can sit there waiting for facts and figures or just do it . Job done!

True LR spirit! However, would you say 160ml is the right amount? I need to know how much to buy... :p
 
One thing to be careful about is getting swarf in the VCU. If the plates are as close as mentioned any foreign bodies in there would spell trouble.
 
Some popcorn to be chewed on....

If the fronts have lost traction, and the wheels are spinning, the VCU needs to drive the back axle. Lets say the fronts are spinning at 10MPH - that's 15KMH So....

15KM = 15,000M
15,000M / 2M (roughly tyre circumference) = 7,500 Wheel Revolutions Per Hour
7,500 / 60 = 125 Wheel Revolutions Per Minute
125 / 60 = 2.1 Wheel Revolutions Per Second
2.1 * 3.2 (roughly Freelander's diff ratio) = 6.7 Prop Revolutions Per Second

So if the difference in front and back prop speeds is greater than (say) 6 or 7 revs per second, the VCU should be 'tight as' (ie transmission damaging levels should all wheels have grip). How much lower than this though should it be 'tight as'?

If you're reversing on full lock - whats the fasted you'd be driving? Probably about that 10MPH. So at 10MPH on full lock reverse, and the fronts travelling the full 12M turning circle, what circumference would the rear axel take? This would give the speed of the back axel and therefore speed difference in props. That would be the level you don't want the VCU 'tight as'.

Probably a bit anal this, but peeps do like popcorn.
 
True LR spirit! However, would you say 160ml is the right amount? I need to know how much to buy... [emoji14]
It's in one of my posts in this thread somewhere the amount I used..I think it was nearer 140ml I could not physically get any more in. It does not take a lot...

I bought 500g or 1/2 a kg of the stuff....I belive this equates to 500ml I only used around 140 ml.

Cost me 30 earth pounds from eBay.
 
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Some popcorn to be chewed on....

If the fronts have lost traction, and the wheels are spinning, the VCU needs to drive the back axle. Lets say the fronts are spinning at 10MPH - that's 15KMH So....

15KM = 15,000M
15,000M / 2M (roughly tyre circumference) = 7,500 Wheel Revolutions Per Hour
7,500 / 60 = 125 Wheel Revolutions Per Minute
125 / 60 = 2.1 Wheel Revolutions Per Second
2.1 * 3.2 (roughly Freelander's diff ratio) = 6.7 Prop Revolutions Per Second

So if the difference in front and back prop speeds is greater than (say) 6 or 7 revs per second, the VCU should be 'tight as' (ie transmission damaging levels should all wheels have grip). How much lower than this though should it be 'tight as'?

If you're reversing on full lock - whats the fasted you'd be driving? Probably about that 10MPH. So at 10MPH on full lock reverse, and the fronts travelling the full 12M turning circle, what circumference would the rear axel take? This would give the speed of the back axel and therefore speed difference in props. That would be the level you don't want the VCU 'tight as'.

Probably a bit anal this, but peeps do like popcorn.
I'm not fond of popcorn[emoji2]

But if someone knows the precise ingredients for perfectly baked vcu please let us all know.[emoji106]
 
I'm not fond of popcorn[emoji2]

But if someone knows the precise ingredients for perfectly baked vcu please let us all know.[emoji106]

Like.jpg
 
It's in one of my posts in this thread somewhere the amount I used..I think it was nearer 140ml I could not physically get any more in. It does not take a lot...

I bought 500g or 1/2 a kg of the stuff....I belive this equates to 500ml I only used around 140 ml.

Cost me 30 earth pounds from eBay.

I just emailed this seller to ask if he will supply 200mls or 300mls of 50,000cst and if so how much. It says in the listing 50,000 is available.
Silicone Oil 30,000cst 30000 T3 Silikonol Syncro 400ml | eBay
 
Um, did you watch the video? Length of lever 780mm, weight 7kg. It seems to have been shot in real time so there's your timescale.

No, not many would want to remove the VCU for testing. My point was, in the context of rebuilding one, that the video might be a guide to whether the job was successful.


yes i did - that's one time - are you suggesting that all VCUs will be exactly the same - we have more figures than that - but you need a lot to be able to derive a consensus as to what is acceptable, what tolerance is allowable and what is definite no-no.
 
yes i did - that's one time - are you suggesting that all VCUs will be exactly the same - we have more figures than that - but you need a lot to be able to derive a consensus as to what is acceptable, what tolerance is allowable and what is definite no-no.

I suppose we need an insider at Bell to tell us exactly how they are tested. That would be the standard to aim for.
 
So long as I can do the one wheel up test and have the weight drop in an acceptable manner (ie freely unlike it was when I bought it) and don't keep spinning the wheels on wet roads I will be happy. At the minute if the road is wet and a little greasy I can spin the fronts in third gear. And that is in a 1.8 K series with no torque! But I guess no weight over the wheels either.
 
Our seller replied and it is interesting. Here is his reply.

Hi
The minimum I can sell is 400ml and the price is £25. Just buy one of my current listings and state the viscosity required in the check out message. Most freelander owners buy 100,000 from me



So he has sold to people repairing Freelander VCU's before, Mmmm, I wonder who they were?
My IRD and Diff could well have been weakened by the tight VCU so I wouldn't consider 100,000 even if it was correct for the original VCU's but might go for 50,000 or 60,000.
 
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