VCU Test

Bell Engineering, who I believe to be specialists in all things transmission related, take the following view

"It has been reported*on some*internet sites*that to test the VCU if you* jack the one back wheel of your Freelander without the handbrake applied you should be able to turn the rear wheel and that if you cannot turn the wheel your VCU has seized -THIS IS TOTAL RUBBISH!* You would hardly be able to do this by hand as you would need a*2 foot breaker*bar and stand on it, the wheel will move very slowly - this still does not indicate whether the VCU is any good or not as all wheels will turn regardless of the condition of the VCU.

Another common fallacy for testing VCUs is the tipex test whereby you put a tipex mark on the shaft next to the front prop shaft and one opposite on the viscous coupling and if these marks have moved out of line after being driven round

If*a VCU has failed it is highly likely that it will have damaged the taper roller thrust bearing in the IRD unit.* There will be no obvious sign or noise and IRD failure usually occurs when reversing the vehicle upon which the thrust bearing collapses and total failure occurs normally breaking the teeth off the crown wheel and pinion which causes the banging and grinding noise."

Discuss.

Is there a sure VCU test?

The Mad Hat Man said:

yes
do a ****in :search:

Click to expand...

Yes, and the tests suggested throughout the forum (one wheel up or tippex) are being challenged by Bell Engineering and I'm looking for people's thoughts.

Is that such a ****in inconvenience?

yes
coz its been "discussed" to death.
You either believe what a concensus of knowledgable experienced peeps have to say or you believe a trader that want you to buy his product. " testing is a waste of time - buy one of my replacements".
A I said - if yu can be bothered to search - yu can read as many "discussions" as you want - if yu cant be arsed, then neither can I.

The Mad Hat Man said:

yes
coz its been "discussed" to death.
You either believe what a concensus of knowledgable experienced peeps have to say or you believe a trader that want you to buy his product. " testing is a waste of time - buy one of my replacements".
A I said - if yu can be bothered to search - yu can read as many "discussions" as you want - if yu cant be arsed, then neither can I.

Click to expand...

Oh I've read your posts on the subject - every thread involves you kicking off like some grumpy old sod.
Have you ever been wrong ..... about anything?

in my experience with viscous couplings which are designed to slip with little torque applied as in cornering but stiffen as speed and torque are to give a diff lock on rr and for the same on freelander but also as front wheels are geared slightly higher the slip needed to allow for wheels doing the same speed but shafts different ,they do stiffen and eventually seize more quickly in freelander than rr as rr is equall driven front and back so gets less work than freelander one ,surely its the seizing wether fully or partially that stresses transmission in freelanders as it does in rr ,testing rr v/c was allways done with bar on unit (degrees covered in certain time at certain temp with given force applied )this is no different to jacking up rear wheel and turning with bar ,with experience you can tell if its stiffening hence me asking people to do it regulary as difference eventually can be recognised and dealt with,if you jack wheel and turn with bar and it wont turn its fair to say its seized ,if it turns resonably stiffly but not back breaking and with a force tyres could easily cope with then its still okay ,admittedly its not exact but thats why checking reg matters ,only done 10s of freelanders but was given method by borgwarner as way of checking there boxes ,when worked for firm that reconned them for lr

East Lothian Freelander said:

Bell Engineering, who I believe to be specialists in all things transmission related, take the following view

"It has been reported*on some*internet sites*that to test the VCU if you* jack the one back wheel of your Freelander without the handbrake applied you should be able to turn the rear wheel and that if you cannot turn the wheel your VCU has seized -THIS IS TOTAL RUBBISH!* You would hardly be able to do this by hand as you would need a*2 foot breaker*bar and stand on it, the wheel will move very slowly - this still does not indicate whether the VCU is any good or not as all wheels will turn regardless of the condition of the VCU.

Another common fallacy for testing VCUs is the tipex test whereby you put a tipex mark on the shaft next to the front prop shaft and one opposite on the viscous coupling and if these marks have moved out of line after being driven round

If*a VCU has failed it is highly likely that it will have damaged the taper roller thrust bearing in the IRD unit.* There will be no obvious sign or noise and IRD failure usually occurs when reversing the vehicle upon which the thrust bearing collapses and total failure occurs normally breaking the teeth off the crown wheel and pinion which causes the banging and grinding noise."

Discuss.

Is there a sure VCU test?

Click to expand...

the statement is misleading.

How would all the wheels turn if only one is jacked up, the other 3 must be on the road and therefore cannot turn ?

It was not meant as a conclusive test, merely an indicator. The wheel can be turned by hand, just very slowly and with a LOT of effort. This indicates that the VCU will allow a quantity of slip, but does not indicate to what degree, it may be very nearly seized, or not at all as it is not quantitive rather more subjective. I may well be able to rotate a wheel by hand whilst the next person may not.

again, the tippex test was meant as an indicator - it would show if the front and rear props were turning at different rates. (the tippex marks should be put on the props not the vcu housing). Again, it wouldn't show the amount of slip allowed, merely that it will slip.

There is a conclusive test, it involves removing the vcu and putting in a vice and hanging a weight from it on the end of a breaker bar of known length and timing it through 1/2 rotation, and then comparing the values with known good ones.

All of the above have been discussed many times on this forum, with lots of different opinions, Hippo (I think) actually did some great write ups with lots of different figures etc.

Unfortunately, I don't have time to search through all the posts, but if you wish, the answers are there.

good luck.

(I have no axe to grind either way with any transmission specialist and the views expressed are merely my own - I have tested my vcu using both methods above (jacking and tippex) and am satisfied that mine is not seized. You may require something more definite, in which case, remove it and send it away for testing)

The thing is.... They are the best checks we have. If yu can come up with a better one - good. Until then don't knock it. Bell do very good repairs, but they have got some things wrong.

Optimus Prime said:

the statement is misleading.

How would all the wheels turn if only one is jacked up, the other 3 must be on the road and therefore cannot turn ?

It was not meant as a conclusive test, merely an indicator. The wheel can be turned by hand, just very slowly and with a LOT of effort. This indicates that the VCU will allow a quantity of slip, but does not indicate to what degree, it may be very nearly seized, or not at all as it is not quantitive rather more subjective. I may well be able to rotate a wheel by hand whilst the next person may not.

again, the tippex test was meant as an indicator - it would show if the front and rear props were turning at different rates. (the tippex marks should be put on the props not the vcu housing). Again, it wouldn't show the amount of slip allowed, merely that it will slip.

There is a conclusive test, it involves removing the vcu and putting in a vice and hanging a weight from it on the end of a breaker bar of known length and timing it through 1/2 rotation, and then comparing the values with known good ones.

All of the above have been discussed many times on this forum, with lots of different opinions, Hippo (I think) actually did some great write ups with lots of different figures etc.

Unfortunately, I don't have time to search through all the posts, but if you wish, the answers are there.

good luck.

(I have no axe to grind either way with any transmission specialist and the views expressed are merely my own - I have tested my vcu using both methods above (jacking and tippex) and am satisfied that mine is not seized. You may require something more definite, in which case, remove it and send it away for testing)

Click to expand...

Thank you

Don't forget that the VCU can also fail in such a way as it always slips. Hence Mondo mode, which has now been plagiarised to mean no prop shaft. Originally it was because his VCU failed in this mode and he then sold the car on.

I get a lot of pm’s about me video showing the one wheel up test. Questions mainly… me vcu is solid un dun’t turn…

Vid was done to help peeps. I can turn my wheel by hand. Does take a bit of effort, but I can turn it so the tread turns about 1 inch in 3 seconds, if I remember correctly. Naturally that aint a good way to measure, which is why the one wheel up test was created to measure the torque applied. Torque and length of bar are important. That’s our only comparison factor. The idea being we could all compile results world wide, and see what the average was. I’ve lost the measurements given to me so far. No great loss as there was only 11 or 13. Real shame as this could have been a chance to help people. If someone tells me theirs turns 20 times slower, then you know the answer. It it drops to the floor, then it’s more likely a BS VCU.

Bell (Austin on ere) also supports the one wheel up test.

Many don’t understand it, so a second video on how to jack up only one wheel and complete the test is on it’s way (filmed but not edited yet). Hand break off, taking up the slack, allow wheel to turn before measuring… has been discussed many times. As said, it’s the only test we have and we int got any betterer test. We were going to measure and film some duff vcu’s with Austin, but it never happened. Feked unit being fitted to ma hippo un one wheel up tested for comparison.

also the tippex test is only a crude method but it doe's work. . . . . .fink bell engineering is getting all smarty pants and i agree wiff floppy its just for trade . . . .most people on here are not going to whip off the vcu and stick it in a vice , so the info in this forum is best for purpose

Been thinking for a while about trying to see if we could collectively kick start the measuring campaign which started some time ago. Was wondering what the best solution would be. Post a request on as many Freelander forums as I can find? Advert on you.tube? Or ming could tow a sign behind his rocket…

just do it regulary on your own vehicle ,i know from experience but aint gonna hit my head on brick wall

You could always drive it round a wet grassy field for half an hour.

Soon tell you if things is working ok.

my point made i think

If your car has done more than 70,000 miles on the original VCU just ask for a recon one for Christmas (if you're lucky)

Hippo - I posted the few results that I knew about on Scribd. Maybe yu could add to the spreadsheet and I will update it?

Let me know of any changes required....

I keep reading this 70,000 miles number and at first it worried me - i was way past that with my original 2003 VCU that's been there from the factory. Now i just don't think about it - i'm on 130,000 miles and all i do is make sure to occasionaly check the tipex lines are moving and take it out on a snowy / muddy field. So far no problems.

DefUnct said:

I keep reading this 70,000 miles number and at first it worried me - i was way past that with my original 2003 VCU that's been there from the factory. Now i just don't think about it - i'm on 130,000 miles and all i do is make sure to occasionaly check the tipex lines are moving and take it out on a snowy / muddy field. So far no problems.

Click to expand...

see post#10

The Mad Hat Man said:

see post#10

Click to expand...

I have got drive to the rear when needed - tested on wet and muddy fields and in snow reading all that i have here about the VCUs, i'm surprised it's still working,but it is.

Edit: Or should i be waiting for a bang and a large bill soon?