Only needs to be one. The vehicle will wake regularly and self level until it cannot achieve it anymore - eg. On the bump stops.
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Only needs to be one. The vehicle will wake regularly and self level until it cannot achieve it anymore - eg. On the bump stops.
Not when you put it offroad height first and then remove the fuse for the EAS to do the 'droop test'.Quote:
Originally Posted by Tombie
The plans vs reality.
During the week, the 4x4airseals valve block o-ring and dryer bits arrived.
The plan :
Refurb the front valve block first to see if it was leaking back into the gallery causing the C1130-66 code and the slow drop (~20mm/day) on both front bags.
Car up, wheel off, peel back a bit of the wheel liner and valve off. I thought I'd pop off the gallery pipe rapidly to see if anything came out thinking that if it was clean I'd finish the day with the valve refurb. Copped a blast of white powder which put paid to that.
The reality :
Valve apart to find visibly deteriorated O-rings and lots of white dust. Clean and reassemble for later. I laid out the orings on the doc sheet provided which made it super easy as a couple of them are fairly closely sized. That way I didn't have to think. Remainder back in the bag for the rear valve block at a later date. Took a lot of cleaning to get all the silica dust out of the valve body and components.
So given the line was full of silica, compressor and center valve out next. As is typical of this car, the compressor housing was missing a bolt, as was the compressor bracket, so remove the 4 of what are supposed to be 6 bolts. Realise I should have removed the rear pipes before pulling the bolts out and put the bottom bracket bolt back in while I wrestle the intake and exhaust pipes free.
Take the dryer off the compressor and pop the cap. Looked like the top filter in the dryer was slightly cocked, so I thought I'll just tap that on the ground to pop it out, forgetting it's holding the dryer media in place. So the filter comes out followed by the media all over the driveway. To be fair I'd only had one coffee this morning. Dryer re-build went as documented with the new cap and back on the compressor.
Time to remove the center valve block. Let the reservoir leak off a little bit and then popped the pipe out to be greeted with a strong and light blast of silica dust. Brilliant. Remove, clean and rebuild center valve. A few cycles of blasting through all the lines and pressurising / de-pressurising the reservoir with the air gun to get as much silica dust out as practical and put it all back together again.
I slotted the top bracket on the compressor while it was out. There is absolutely no way I could see of getting to that bolt with the top soundproofing cover on other than with a ratchet spanner up past the dryer, so I didn't even try. I figure without the soundproofing I might be able to go over the top of the compressor with a long 1/4" drive and a universal joint, but I could not get the cover off with the compressor in place so I figured I'd have no way of getting it back on.
The reservoir leak to gallery seems to have gone. Everything functions as it should and it's currently sitting at offroad height sans fuse 26 to see if it drops at all overnight.
One trick I found handy was to get a bit of light silicone spray into the top and bottom of the voss connector and work the tube back and forward to free it up. After that all voss connectors went in with nothing more than finger effort and an 11mm spanner to nip them up.
Checking the records, this compressor has about 70,000km under its belt and was a brand new Land Rover Hitachi sometime between 2012 and 2015 (the car was off the road for a few years after snapping the crank). The desiccant had a significant amount of powder.
For the record, I have a good condition genuine Hitachi dryer cap if anyone needs an emergency spare on a Sunday arvo.
I didn't do the rear valve block as that passed all the previous leak tests. Let's see if it stays up now.
It's looking like a win. This is for a D3 with the 2010 software update for the Hitachi compressor. Apparently the pressures are different for a D4, so I wouldn't be surprised if the algorithm differs also.
On startup (after a wakeup) if the height hasn't changed outside of tolerance it appears to :
- Open the reservoir valve and measure the pressure. If it's within ~1 bar of the max pressure (according to the book) then
- Close the reservoir valve
- Open the exhaust valve and vent the gallery
- Close the exhaust valve
- Turn on the compressor
- Wait until gallery ~> 6bar is reached
- Turn off the compressor
- Vent the gallery.
If the reservoir is lower than 1bar of max pressure then
- Turn on the compressor
- Wait until gallery gets to > 17.7 bar
- Turn off compressor
- Close gallery valve
- Vent gallery to ~ 2.5 Bar
If the height has dropped (it was 28 degrees when I parked and it's 4 degrees now), then
- Start the compressor
- Open the reservoir valve
- Raise to correct height
- Same as reservoir lower than 1bar of max pressure
If it's in the same wakeup then it only checks the height to be within tolerance and doesn't do any of the reservoir pressure or compressor function tests.
On mine, after a "charge up" the gallery vents twice because it bounces back above 5 bar and vents again. Seems to settle between 3 & 4 bar (might be an issue with wear on the center reservoir valve as there's a pretty significant detent in the rubber of the valve face from wear/age). It does seal however, whereas it continued to rise > 5 bar before the valve block re-seal.
So it appears the compressor runs on *every* start after a wakeup event (I haven't been able to ascertain how long that is, but if I pop into the shop quickly it doesn't happen when I come out again), even if it's for a matter of seconds.
The manual says the pressure tolerance is ~1bar but on mine it pumps up to 17.7 Bar and doesn't seem to spark the compressor until < 16 Bar. Hard to really say as the Gap takes a while to refresh and the measuring cycle happens pretty quickly.
All the 2010 software update for the D3 does is vent the gallery if it's > 5 bar (on mine it generally vents to ~2.5bar) when idle to ensure the compressor isn't trying to start into a high head pressure.
With a 24 hour time lapse, it's interesting to watch the car move around as the outside temperature changes. As you'd expect the pressure in the springs changes with temperature (as per the ideal gas law) and the car tends to move around a tiny bit, but when you take into account the static friction on the suspension components it tends to happen in small "bursts". I guess that's "slowly increase the torsion on a bush until it goes *squeak* and re-positions".
Just a final thought but maybe the Gap reports pressure absolute, so 16.7 bar above atmospheric becomes 17.7 bar on the gauge. That'd make more sense in relation to the pressures listed in the book. So max pressure of 16.7 bar becomes 17.7 on the Gap, and minimum of 1bar in the gallery becomes 2 bar on the Gap.
Brad, hope you had breathing protection on when you copped the blast!
Yeah, I wasn't that smart which is pretty silly given I have a pack of N95s. Spent the best part of Saturday arvo through yesterday coughing. Same as when I last went under the house. Loads of fine dust in the air.Quote:
Originally Posted by Tombie
Still, at least I wasn't dry cutting a stone benchtop with a 4" grinder.
It was quite something to see the fine sparklies in the sunlight from the darkness under the car. Almost reminded me of fine mica dust. A bit like when I binned a bike at the race track, knowing something bad was happening and looking up at the shower of "pretty sparks".
"Stupid is as stupid does".
Awesome find and write up BradC. I live in Albany and know what you mean about the cold nights.
Hoping to revive this thread. Have the same c1130-66 code, came on the first time on long drive from Darwin to Adelaide whilst towing camper trailer, then a couple of times since on same trip. Usually after a few hours towing, but once only 20 mins after starting.
So I have done the 'droop test' overnight expecting something to drop - however no drop? Just wondered if any suggestions about where too...compressor was replaced about 2 years ago. 2014 D4 SDV6 at 120000km. Also only just had timing belt service done.
Would you still start with valve block service? Appreciate any advice.
Start with the center valve block. Easy to get to and if it's full of dust you know you've got to do the whole thing.