When I had mine done (twice) by the local National Aircon people the young lady doing the job also didn't run the engine during filling. She just evacuated the system, did the nitrogen check for leaks and re-filled it. The we started it up and verified that it came down to temperature as per RAVE. She said it was interesting to have the official manual to do the right checks.

Also reckoned that underfilling is bad for the system. Told me that on an older car its a good idea to do a re-fill every 3 years or so even if the A/C still seems to be working OK as an older system will very slowly loose gas.

Not impressed by Halfords, Kwikfit or garages with a machine in the corner and a certificate on the wall. Guaranteed underfill. Especially on a high volume system like the P38. She said that frequently you just get a standard amount shoved in, maybe choice of small system or large and thats it. Certainly when Halfords did mine the first time they under-filled it as the fill lasted about 6 months. Her full fill lasted about 18 months and confirmed I had an intsy bitsy teeny weeny leak that wasn't properly showing up under test. But the fill had the UV indicator stuff in it so sufficient traces were left to confirm a leak.

Clive

Thats a piss take! Sounds like they are quoting for all four wheels on an L322 where, notoriously, nothing wants to move. Especially at the back! Even then its top end.

£30 to £50 seems to be fairly typical. Maybe this website is worth a try :- https://bookmygarage.com/blog/wheel-alignment-cost/

Think I'd want to be sure that things are pretty much right before trying the DiY laser kit. All this sort of thing is so much easier when you know what a good one looks like. Small errors will probably be fairly easy to handle and understand but if its got weird issues ...

Clive

Island listing for Boge fronts is OEM as in Original Equipment Manufacturer. Which doesn't necessarily mean original factory specifications.

I bought both front and rear Boge OEM from Island a couple of years or so back. I'm unconvinced that they are made to the original factory specifications although thats obviously a very difficult thing to assess when comparing old, factory, shockers with new ones.

Best I can say is that the damping doesn't seem quite matched to air springs. Air springs being inherently variable rate I'd have expected some shim stack differences to cope with the rate variation as opposed to the linear rate of coil springs. These sometimes feel caught out by spring rate changes on decent suspension excursions leading me to suspect that the shim stack, or equivalent damping control, is expecting a linear rate.

That said my main previous experience with air suspension was with Fournales motorcycle units which are much smaller volume and operate at higher pressures than the Range Rover system so have significantly more change of rate with travel. Poncing about with the pressure was good education in why damping has to be matched to spring rates and loads. I was never convinced that Fournales actually knew what they were doing when it came to road applications. An expensive lesson in not to believe the hype!

The damping action of my Boge OEM shocks sometimes feels a bit reminiscent of the Founales motorcycle ones when the baseline pressure didn't match what the damping side of things liked best.

Clive

Although its not supposed to be necessary with live axles both ends its probably worth forking out for a Hunter or similar four wheel alignment check just in case there is something seriously weird going on. Allegedly many KwikFit branches have Hunter equipment and will do the test for free. Not sure that I'd trust them to adjust things tho'.

Unlikely to be anything odd but I'm prejudiced mostly because pretty much everything folks bring me to fix or diagnose is odd.

Clive

Fortunately there is just enough room to get between the radius arm and the mounting to cut through the centre bush and bolt. Still leaves you with a thin "washer" holding the bolt head end on so the head end has to be bashed out.

One of many times when I really, really wished for a proper full lift hoist. In the process of putting a scissors one in the garage but only 12 ft ceiling so it won't go right up. But better than 16" on the ramps.

Clive

Trying to undo the seized ones on mine just ripped the centre bushes out of the rubber. So bush and bolt turned together. Only option was to cut.

Out of curiosity I tried extracting one of the cut off bolts from the centre bushes. 12 ton ram didn't budge them. So corroded together good and proper.

Next time if they don't pretty much come straight out I'll be cutting. No point in wasting time struggling for half an hour and still ending up having to cut. Find that the older I get the quicker I reach for the saw or grinder.

Clive

Genuines are alloy. Plenty thick enough in the wall not to crush. If bolt is not coated with copperslip or stubborn grease intermetallic corrosion between steel bolt and alloy centre tube will lock things solid. Modern bolt plating is inferior to what was used in the factory build. I'd have the grinder out and ready for anything thats been in there over 5 years! Might come out OK, might not.

Clive

Concerning the bush compressor insertion tool sizes mine goes from 69 mm Ø at the large end to 58.8 mm Ø at the small end. Taper section is about 16 mm long, angle approximately 6°. About 6 mm of parallel section at both ends. Whole thing is just under 30 mm long. I made it by boring through to small end diameter, adding a 6 mm deep recess at the large end size there cutting the taper until it ran out of the small end diameter. I didn't really bother control the depth of the parallel parts.

Its arguable that the plain big end diameter would be better made longer to give more support to the bush when first loaded. Might be easier to push bush through if the taper were made shallower and longer too. Made the length it was 'cos I couldn't be faffed to set up a longer boring tool. But it works well enough.

Clive

Hi Rob

PM me your E-Mail address and I'll send it all over along with the dimensions for the height sensor arm pivot pin. I make new stainless steel pivot pins as a matter of course. So far out of 3 sets of radius arm re-bushing jobs I've found two pins so badly corroded that the arm pivot wouldn't move any sense, two that were still free but well rust pitted and two that were, by garage standards OK to re-use. So looks to be a reasonable chance of finding unserviceable ones. By my standards all I found were useless but I'm an Inspector Meticulous type given half a chance.

My drawings cover more than you need if you do have access to a press. Although a force screw works its darn hard work. Press is far better.

Clive

Thanks for the help. Great link to the group test puts things into perspective.

Gotta admit that these high capacity small packs scare me. 20 year old Clive spent an "interesting" month doing load / power delivery tests on thermal batteries. Having both battery and load glowing red hot on the bench in front of you after a 5 minute full load discharge test rather makes the point about high current issues. 5 minutes being always long enough for an anti-tank missile.

Naturally having got it all together Her ladyship has changed her mind! She is going to take the battery off over winter and keep it in the flat hooked up to a maintaining charger.
Wimmin.
Still think I might get one for me tho'.

Clive

Thanks for that information. Pretty much what I expected so gonna be pot luck. Decisions, decisions!

£35 cheapy or £80 for one with a separate 12 volt power bank output off t'Bay. Or wait until next time round at LiDL as their Ultimate Speed branded one looks adequate VFM with a warranty. Certainly the little LiDL battery chargers are quite decent. Always bit of crap-shoot for boy-toy things out of LiDL. The good stuff is more than decent, especially given the price, but the not so good usually re-defines horrible.

On the bricks and mortar side EuroCar have an offering and Halfrauds list several, albeit the apparently decent ones seem expensive and not on shelf at the nearest branch.

Clive

Kev

I bought a spare set of radius arms for about £20 locally to rebush and exchange for mine so if you are doing your own the cost probably isn't a game changer.

I made my own tool-kit after the Laser Tools offering proved not to fit the P38! If you know someone with a lathe I can send you drawings. 8 pages worth! But thats for a comprehensive tool set using a threaded pull rod. If you have a press and one of the cheap chinee universal bush removal sets you probably only need to make the compression tube. Still need the drawings to verify that you have the right sizes of pressing tubes tho'. I used my set once with the threaded pull rod to prove the point then did the other bushes in the press. Much easier.

Clive

Has anyone got any experience with the baby "jump start" battery boxes?

Right now specifically interested in using one as a 12V power source for the alarms and anti theft devices on Her Ladyships BMW K1200LT which flatten the bike battery in about 6 weeks - 2 months. Garage in separate block so no power. I figure that she can easily pull something that small and, basically, portable off every week and take it back to her flat to recharge overnight. Presumably when it goes back on again it will top up the main battery whilst looking after the alarms et al. If I find one that works for her I plan to get one to do same job on my P38, which usually needs a top up charge a couple or four times a year if I'm not out and about much.

Problem is deciding on what is a good brand, which capacity specification to believe and whether a separate 12 DC output alongside the jump start one is useful. far as I can see most of the usual suspects quote the capacity for the USB 3.2 / 5V output in milli amp hours to get nice big numbers. Real 12 volt capacity seems to be around 1/3 of those numbers. Say 1 1/2 to 3 amp hours for the under £100 market.

Clive

Drawings and blurb in your E-Mail.

Holding straight is really only an issue when working solo. Those arms get heavy pdq! The bend really doesn't help.

Clive

RR

PM me with your E-Mail and I'll throw a pdf copy of my "complete" tool drawings across.
More than you need but its all there.
I think! Needs someone else to check them anyway.
My drawings are for one actually intended to be used with a pull screw as per the Laser tools "doesn't actually fit a P38" jobbie. Tried my set. It would work but nuts take a deal of turning to generate enough force to shove things in. Realistically a press is far better. Worst thing about press is holding things straight. Not quite got that bit sorted for doing on my own yet.

Or if you don't fancy making I guess I could box my bits up and send them by courier.

Clive

Rcutler wrote:

Yes I am hoping we can sort out another weekend, as again the radius arm and suspension work looks like a great plan. It might be worth trying to loosen some of the bolts before we head down next time. Obviously re tighten but an angle grinder was used on Gilbertd's car. Also the bushes do not come in a kit make sure you have exactly enough.

Best to get all new bolts and assume the old ones will need to be cut. Centre tube on my factory fitted bushes was alloy so corrosion lock against the steel bolt was inevitable given time. Sheradising, zinc plate et al will hold things for a while but anything much past ten years and you are on borrowed time. Cadmium plate is an effective protection but that's been verboten since about the mid 70's.

One of mine came out with (great) difficulty. The other three I eventually gave up upon and had to cut. No way I was re-using the old ones so wasting most of the afternoon trying to get them out was less than clever. Next time if two or three bashes on a bolt end don't drive it through far enough to hide the thread its getting cut. Or just cut and be done.

Clive

Its worrying how marketing buzz wins out over proper engineering.

It should be self evident that a polybush system can only work as advertised "provide improved control due to consistent steering geometry" when used as a cheap substitute for rose joints. With a bit more compliance for better NVH (Noise, Vibration, Harshness) levels. Rose joints are rough riding. Of course any significant compliance promptly interferes with the preciseness of the steering geometry. Somewhat contradictory. Time to quote Emerson.

Most road vehicle suspension systems aren't geometrically good enough to work freely over the full range of movement when rose jointed so the compliance of rubber bushes not only controls NVH but also gives that essential "give" to let things articulate properly. If you start seriously looking around car suspension systems its clear that there is some pretty serious engineering going on in the rubber bits. They don't do void bushes and the like for fun.

P38 suspension geometry is basically that of cantilevered leaf springs. Whatever your views on old fashioned, cantilever leaf springs with solid axles are a pretty good system so long as the tyres have reasonably deep sidewalls, especially when stabilised with a Panhard rod. So long as you ignore the inconsistent friction and self damping characteristics. Which is probably OK if you keep below 50 mph! P38 variant keeps the advantages and sorts the friction / damping issues but has to have controlled compliance. Rose joint it and it will pretty much lock solid in roll. Bump steer is going to be interesting too. Rigidly consistent steering and suspension geometry you don't have. What you do have is carefully balanced and compensating "compliance errors" that make the system work well. Appropriate sized tyres, deep sidewalls not boy racer rubber bands, being more than a little important too.

Given that Richards orange poly bushes worked pretty well for a decent mileage the the things clearly don't work the way the maker claims. Cheap Britpart et al blue version falling apart in pretty much nowt flat show what happens when they are sort of made to theory and hammered by 2 tons of P38 saying "I'm rolling so shut up and take it".

Not sure that I'd be happy spending money on something allegedly "better" that just doesn't work the way the makers say. Also deeply skeptical of the development abilities of "we make (aftermarket) bits for any car" firms against the real vehicle manufacturer who is going to put serious resources behind getting it right so they can make many thousands of cars and keep the customers somewhat happy. Whatever your views on Rover and BL in general the primary failings were production side, not engineering side. Bearing in mind that hitting the price point is hard and engineering compromises are inevitable. Which sometimes don't compromise as happily as was anticipated.

As the man says "sell the sizzle, not the steak". Most customers aren't equipped to analyse things properly. Especially as new "near enough to sort of work" will, initially at least, be an improvement on tired old soggy standard. Remember the instructions on all those snake oil economy devices "First give the car a full service and tune up so its running properly". Might as well have stopped there and saved on snake oil. Or the old motorcycle tuners trick. Put a decent step about halfway up the power curve to make them rev it out properly in second and third. Feels faster but why not just rev it out in the first place!

Clive

Never cared much for affordable laser pointers in alignment devices. Too much futzing around to get them closer than sort of right as body and beam are rarely well enough aligned.

If a two piece device, one part plugged in the axle case and one part plugged in the swivel hub is OK, easy way is to make the facing ends square so any mis-alignment shows up as a step. Visible if large, finger feel if small.

Way I'd tackle making a two part device would be to start with an over long chunk of metal in the lathe and centre drill the far end for tailstock support. Turn one end down to sliding, shake free fit in the axle case and the other down to a similar fit in the hub leaving a section of suitable length in the middle oversize. Over to the mill and cut the oversize middle part square. Slice into two parts apart around the middle of the square bit and face ends true.

Insert the two parts in axle case and hub respectively, turn so a flat side of each square is on top and slide together. Look and feel for mis-alignment. If you want to be really precise bore both sides to take a reasonable size rod. Sliding shake free fit again. But its got to be made dead nuts in line on both to be worth the effort. I probably wouldn't bother.

Centre bit doesn't have to be square. A simple flat will do. Carefully filed if thats all you have. If you are young enough and desperate enough ways could be found to do it on a Chinee Mini Lathe! I'd ask someone else.

Clive

Looks easy enough to make the alignment tool, or an effective substitute, if the dimensions were known.

If anyone has the sizes I'll make one that can be loaned out as a forum resource.

Allegedly the dimensions are out on t'net somewhere but darned if I can find them.
Picture of a home made one comes up fairly easily, usually with associated comments about sizes and promises to post them but ...

Given a complete axle it could probably be reverse engineered without major problems. Saving the usual "(expletive deleted) thing is (expletive deleted) heavy" issues. At first sight the official version seems rather over-engineered. But never having used one there may be reasons that are not obvious to a casual observer.

Clive

Gilbertd wrote:

Clive603 wrote:

Depends on whether it behaves like nylon or delrin.

Problem is it behaved more like marshmallow! Not like plastic at all, very soft and squidgy but also very tough to cut with anything.

Urg. Sharp Rotabroach will shift that sort of stuff but big issue is controlling the feed through rate. With the slow spiral on the flutes its going to want to pull straight through in about a turn or two. if it does that the big issue becomes whether or not you have the power to make a complete rotation at the end and snap the whole mess of swarf off. Alternative is a controlled low rate feed which will nibble it out in little balls. Which does work with rubber but you have to get the rate of feed right otherwise it squishes in under the cutter which takes occasional big bites. Not the sort of thing that's easily done in the ordinary garage workshop. With rubber best answer is to freeze it and hit it fast before it cottons on to whats going on. Even if freezing works for ploy bushes a complete radius arm will need an industrial freezer!

If its that soft a Forstener bit might work. Cut will have to be in thin slices so you still have the issue of controlling feed. The edge might hold it back enough so things can be controlled. Lubricant will help. Synthetic cutting oil would be best but normal folks don't have that sort of stuff about the place. WD40 spray should work adequately.

Clive