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D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

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  #21  
Old 24th February 2020, 12:47 PM
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Goran Goran is offline
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Well on top of everything else, range estimate was at 0 so I did a test run to get some fuel. On the plus side I made it back home.
However, the unassisted steering is soooo heavy I barely made it out of the drive
The whole adventure took around 12 minutes and it kept running, so maybe it can make it?

Although I am so worried hitting stuff because of the heavy steering, I may just order a flatbed truck.

Now I know why those 80's truck drivers had such huge arms

Just for info, I charged the battery back to full again, using a smart charger which displays capacity that went back in.
It put 4.8Ah back in. It seems to add up, at 25A draw, that's 11.5 minutes
Looks like I could have made it to the mechanic, if it wasn't for the heavy steering, especially at slow speed. It wasn't worth the stress. RAC charged me only £33 to upgrade to home start.

Last edited by Goran; 24th February 2020 at 02:00 PM.
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  #22  
Old 24th February 2020, 02:06 PM
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These little RC chargers are great! I was worried I didn't have a charger that can charge LiFePo4, as it turns out this little charger I already had for RC planes can do it!
Charges at 4A current.
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  #23  
Old 10th March 2020, 07:35 PM
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Well the new (remanufactured) rack is in. Its not a cheap job, 7.5 hours labour!
I have to say I made a mistake! I ordered a non-servotronic rack on purpose, but I forgot how those feel. I have been driving around with a non-working servotronic rack for years and really liked the heavier steering at slower speeds which made the steering feel more precise in my opinion and gave the car a lot of character. It felt like a big car. It felt more sporty.
Now the new rack is in the steering feels so light! I dont like it at all.
I may have to swap a remanufactured servotronic rack back in when I have time/money to blow
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  #24  
Old 10th March 2020, 07:42 PM
MikkiJayne MikkiJayne is offline
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So a broken servotronic rack is heavier than a non-servotronic? Is it any different while moving? I really dislike how light working servotronic is at low speeds - it feels like driving on ice.

What was leaking on the old rack?
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  #25  
Old 10th March 2020, 10:42 PM
HPsauce HPsauce is offline
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Quote:
Originally Posted by MikkiJayne View Post
I really dislike how light working servotronic is at low speeds - it feels like driving on ice.
I honestly never noticed that on my PF S8 which had it, it was brilliant!
I particularly liked the way it firmed up at "higher" speeds, it was rock solid at 140-150mph.

Though I did once have a real "driving on ice" effect from the power steering on a Rover 800 that failed in a very unusual way.
Basically it lost all road feedback, so if you were stationary you could spin the wheel and it would turn to the limit and "bounce" back to the other side, probably cycling 4 or 5 times before the bounces reduced to nothing.
It was actually just like driving a big old American car so it wasn't as tricky as you'd imagine, but very very weird at first.
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Last edited by HPsauce; 10th March 2020 at 10:46 PM.
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  #26  
Old 12th March 2020, 12:25 PM
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Quote:
Originally Posted by MikkiJayne View Post
So a broken servotronic rack is heavier than a non-servotronic? Is it any different while moving? I really dislike how light working servotronic is at low speeds - it feels like driving on ice.

What was leaking on the old rack?
I really disliked how light the servotronic rack was at slower speeds too. I only found out how different it is on my old S8 when the servotronic relay failed. At first I thought it felt too heavy at slow speeds but I quickly got used to it. So when I bought my current S8 which had a working servotronic rack, the first thing I did was pull out the relay
It felt great, much more precise because a bit if extra effort was needed, and it just felt right for the size of the car, like you could feel what the car is doing.
I was hoping the non servotronic rack would be a bit heavier than the servotronic, but it seems just as light as a working servotronic.
Just pull the relay if you want to try it for a few days.
They gave me the old rack back, he said it was one of the hard lines on the rack. I’ll have a look and let you know.
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  #27  
Old 12th March 2020, 01:28 PM
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I just had a thought it could be because the manual car is less heavy? Its hard to remember exactly, I think that the auto felt heavier with the relay pulled. The manual feels just right. And with the standard rack it feels too light. Maybe the standard rack feels better on a auto car?
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  #28  
Old 22nd March 2020, 10:33 AM
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Sorry to rant even more
I drove my father in law’s Citroen, I think its a C3?
The steering felt heavier than on my D2!
That is just depressing
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  #29  
Old 22nd March 2020, 10:59 AM
MikkiJayne MikkiJayne is offline
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In theory it should be possible to tune the servotronic to be weighted just how you like, anywhere between broken and max assist. Its just a PWM signal on the solenoid, with a ratio of speed to pulse width controlled by the module. Either fiddle with the speed signal in to the module, or drive the PWM directly with something like an Arduino and you can have whatever configuration you like.

If it was just one of the pressure lines failed on your servotronic rack thats a pretty simple fix using stainless braided hose and banjo fittings. HEL (who are 6 miles from me and do stainless brake lines) could make those up easily enough, then you could reinstate the servotronic with custom settings. I have three D2s with servotronic now so its something I want to investigate.
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  #30  
Old 22nd March 2020, 11:33 AM
ainarssems ainarssems is offline
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Servotronic on my S4 feels like it's either on at very slow speed or off once you get moving. I have not noticed any gradual increase or decrease in assistance.
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