Got the engine back and now have the heads on.

Run into a new problem - the britpart valley gasket won't fit and trying to persuade it resulted in it creasing and splitting.

Does anyone have one spare who is reasonably close to me, or does anyone know where I might get one tomorrow?

That's a shame :( Split tailgate too! Or was that a modification facilitated by whatever that green heap is/was?

A 6 speed 540i? Nice. Getting a bit rare those now! And the boxes go for silly money.

What about if you go into neutral as you come to a stop, does it still do it?

I have a slight uneveness as I come to a stop that still seems to be present in neutral - the only brake bits I haven't yet touched are the rear disks/pads so I'm blaming them on mine.

That's certainly a leak :)

You probably won't find those o-rings in universal AC o-ring kits - they're really large on the GEMS compressor connections. Part numbers are STC3177 and STC3176.

Ironically, the system is more likely to leak if its not used regularly (assuming, and I hope it does, the patch on the condenser holds), as the oil circulating keeps the o-ring seals from drying out. Had a couple of cars myself where this has been the case.

When I bought my 5 series a few years ago, the previous owner never used the A/C, and the gas had all escaped. Filled it up with refrigerant and UV dye and its been fine since. I wish the P38 A/C was as good - the BMW really will freeze your giblets off if you so wish!

I can't recall any noticeable increase in fuel consumption when I got mine working, unlike my first car - an 800cc Daewoo Matiz. If you were coasting in gear and turned the AC on, it was like tapping on the brakes lightly :) Poor gutless little thing. Needless to say, it was rarely used, and lost its gas.

The dryer is there to deal with moisture that gets into the system during assembly or other times when the system is open to atmosphere. But it can only absorb so much. Some also act as a filter, and an accumulator for refrigerant to pool in as liquid.

The problem I see with the DIY kits is on a system with no gas in it, how do you displace the air, and get a proper charge? As well as removing the air, pulling a vacuum on a system properly will boil off the moisture on surfaces inside too.

A P38 takes 1.3kg of r134a too, which isn't a small amount to try and get in. Most cars have half that. I had a multisplit heat pump on my house that took 2.7, for comparison.

But hey whatever works is up to you :) I will do dryers as a service item if the system has been open with a leak etc - a P38 dryer is about £35 delivered last time I bought one. Condenser was £80-90. Couple of proper o-rings, and then a nitrogen test and charge around £50. To me A/C in a car is a must have rather than a nicety, I don't do well with heat. With an entirely black interior (even the head lining...) and leather seats, it would be unbearable in this weather.

If the small pipe on your A/C compressor is hot, but the large one is not cold soon after engaging (say 30 seconds at most), its low on gas or may have none at all and could just be compressing air. If its not cold, check the large pipe at the firewall too where it comes into the engine bay - see what its like there.

In a UK climate, the two electric fans generally never actually come on if your viscous fan is working properly, they are only turned on by the single and trinary pressure switches which are based on pressures in the system. The viscous fan keeps the condenser sufficiently cool to negate them ever needing to come on. The only other time they would come on is if the engine is overheating, but its usually too late anyway!

Also if bridging the terminals of the trinary switch only brings one fan on, that will be the high speed mode, suggesting the other fan is open circuit (either unplugged or broken motor), as they are electrically connected in series in the 'low' speed mode. The low speed is turned on by the single pressure switch. If all were working properly, bridging the single pressure switch with the engine running and A/C on should run the fans in the low speed.

In high speed, they're connected in parallel, should both spin and make quite a noise.

Thanks for the offer - hopefully will be dropping the block and heads off at a machine shop tomorrow for them to repair the thread (and perhaps do the other holes that were problematic) and put the heads on. That way if another does go, its already with them to repair again etc.

Obligatory pic:

Combination of differing metals and the foam block that sits above it holding water in.

Replace the condenser - you need to do the dryer too as the system has been open to atmosphere for sometime and the desiccant material that keeps moisture out of the system will all be saturated.

There can be several hundred psi in the condenser when operating. If it doesn't blow out, a lump of now solidified goop may end up getting munched by the compressor, or block up the expansion device in the evaporator and ruin that. Doesn't seem worth the risk.

Ran a tap down the problematic holes. All fine bar one... thread pulled out on the last tightening.

Pissed off.

Problems.

ARP studs - one side will thread in but are not all straight, I can't drop the head over them at all.

The other side - none of them will thread in and I don't want to force them.

Ideas?

The covers have been shot blasted and powder coated on the outside, to a very similar colour as the car. Cost £40 and they look so much better than the usual flaking black paint and oxidation!

There is a new sump gasket in there too - but frankly I'm a fan of RTV both sides too.

I may have gotten distracted and started degreasing the engine bay. Discovered bodywork under all the grime!

Shiny bits:

And what I'm currently sat staring at. Oil strainer cleaned and refitted and sump back on. Heads next.

If the centre of the A/C pulley is spinning the clutch has engaged - the small pipe should get hot, and the large one should get very cold (but not freeze up with ice etc).

If the large one is cold, then the evaporator inside the car should also be cold.

If they both feel the same, something isn't right and no refrigeration is actually happening. Maybe someone has bypassed a pressure switch, or the switch could be faulty. I wouldn't run it like this though as the gas also moves the oil around the system to lubricate the compressor.

Being jacked up / lowered onto seems more likely than my suggestion - unless there is evidence of it being pushed back too maybe.

The paint on the bumper looks a bit like its been a bit...squeezed? PO attempted to run something over maybe?

Impressive though!

I think there are probably still too many of them about for them to consider the P38 worthy yet..

Mind you, with the number of them being broken by anyone with a driveway at the moment, there won't be many for long!

It is, yes. The motors and potentiometers are all part of one unit.

At some point I will get another unit to have a go at finding some way of fixing them as neither of mine return properly, so like most the function is turned off. I'd quite like it to work though - I find it quite handy on my BMW.

Yes, its fiddly, but they can be taken apart.

Don't be surprised if you find the reverse mirror dip functionality doesn't work properly on the replacements if yours currently does - most don't! The potentiometers responsible for keeping track of the mirror position fail, and are built into the mechanism and are not replaceable or fixable. Or at least no one has been able to thus far.