Project What has two seats, a mid-mounted 6 cylinder engine, and a turbo? Rewire complete - finally success!

[mat_the_cat]

Just realised that I'd missed the 'money shot' with this job! There is about 1 degree difference between hitting the bottom of the screen or spurting over the roof, so adjustment took a while.

But eventually got there!

The downside is that it drains the already undersized reservoir more quickly - I actually used half a tank just doing the adjustments...

 

[High Jetter]

I use a safety pin as adjuster tool for mingebag h2o consumption

[mat_the_cat]

Yeah, I know how to adjust them - it's just that with the jets being in the same plane as the screen, any adjustment is more sensitive than if they were bonnet mounted aiming at a screen at a different angle.

On the subject of angles, I'm reminded not to leave the roof vent open when under cover, and then drive off before closing it...

At least replacements are available, and easily fitted.

It hit a bit of a milestone on Friday, and finally clicked over 300k miles.

There's a few things which are showing signs of wear, but on the whole it's held up well.

Almost got driven into today, obviously I must have been in their blind spot.

 

[Talbot]

On 03/08/2024 at 23:47, mat_the_cat said:

There is about 1 degree difference between hitting the bottom of the screen or spurting over the roof

A worthwhile upgrade might be wiper-arm mounted sprayers.  Not dis-similar to your BX, or 405s of the same era, although there are now "better" systems used on things like sprinters and other vehicles with limited locations for fixed spray nozzles.

You go through a lot less screenwash with that sort of system.

[mat_the_cat]

I'm embarrassed to say I didn't even think of that, as it's a better system IMO. There's quite a few neat little engineering touches on the BX (and some dubious ones also!)

[mat_the_cat]

Can't remember if I mentioned this before, but it suffered water pump failure on the way down to Shitefest. There was an awful screeching sound, and no water being pumped. Had to resort to the manual foot pump in order to make a morning cuppa

Bizarrely though, it started working again as normal, so I suspect the impeller was spinning on the shaft. It was taken straight from the early '80s donor caravan, so it's lasted pretty well! I bought a replacement which had the advantage of being self-priming, meaning I could do away with the foot pump.

The new pump seems more solidly made, and spares are available for it - although given how well the flimsy original one lasted, I doubt I'll be wearing it out any time soon. It's also a fair bit bigger, but I'm not really short of space in the undersink cupboard.

Job done, and quieter to boot.

[mat_the_cat]

Bit of a last minute holiday, as we looked at a map of France and put my thumb on an area we've not explored before. Tunnel booked a couple of days prior to crossing, and hit the road! (Via the best overnight spot in all of Buckinghamshire...)

Doing a spot of cycling, running, and drinking - not necessarily in that order of priority.

As ever France doesn't disappoint with scenery:

Also spotted another LT friend lurking in the background!

[mat_the_cat]

We're almost into Switzerland now, and the weather has turned so we may drop down from the mountains tomorrow.

Couple of minor niggles, as the front wishbone bushes have started to squeak *again*! Originals lasted 220k miles, replacements have needed doing twice in the 80k miles since...

Also the fridge has stopped working on 12V whilst travelling. Not had chance to investigate fully, as I've just run it on mains via the inverter on the move (which is actually handier when we're regularly stopping, as short stops fine without the need to light it on gas). 

[mat_the_cat]

2000 miles later, with zero traffic jams whilst in France, we crossed the tunnel and got 27 miles before this.

This was the first of 7 significant delays in the 300 mile journey home - being away just really brings it home to how crowded this country feels. As usual though, we brought some wine back with us to keep the holiday memories alive.

Chosen purely on vintage and ageing qualities, and nothing whatsoever to do with the name.

On 22/09/2024 at 22:11, mat_the_cat said:

Also the fridge has stopped working on 12V whilst travelling. Not had chance to investigate fully

 

Finally got round to taking a look, and yes, no multimeter needed to diagnose this one!

Where I've mounted the relays is a bit awkward, and this was not visible until it was removed. I have a plan to redo the 'house' electrics, so hopefully will be able to resite the relay bank somewhere more accessible.

[mat_the_cat]

FFS. Two windscreens in a year. In fact the first chip in the new one occured a couple of weeks ago, but that was more annoying than problematic. But this one has cracked top to bottom. Both caused by vehicles overtaking me on multi-lane roads; they possibly could have left it longer before pulling in front of me but just bad luck really.

In other news I've gone for some extra leisure battery capacity; original lead acid on the right, new lithium on the left. In theory this should allow us to run the AC overnight, even off grid.

This would be an absolute game changer for touring France - it would be preferable to do 'stuff' during the nicest part of the day, and just travel in the evenings - but using campsites you generally have to arrive early evening, and therefore travel during the best part of the day. It would be lovely to just pull over wherever, without having to suffer a sweaty night.

[High Jetter]

12 minutes ago, mat_the_cat said:

Both caused by overtaking vehicles on multi-lane roads

Stay in lane 1 then?  Double glazing, innit.

[mat_the_cat]

I've edited to clarify; it was vehicles overtaking me which caused the stone chips. Most of the time I am in lane one at either low 50smph, or just under 60 (to avoid snail racing with trucks).

[Westbay]

"In other news I've gone for some extra leisure battery capacity. In theory this should allow us to run the AC overnight, even off grid."

Good idea ! then I thought - how ?  looked up on the good 'ol e bay and 'portable car/home aircon units' about 50 quid !!

Question is this the route you're going or something else ? (nod to your lateral thinking )

ps love the build 

[mat_the_cat]

If you cast your eye back to page 6, I actually fitted the AC back then.

I had to use a caravan type AC unit, in order to find one with a low enough current draw that I could realistically run it from the alternator whilst driving. But it's not as powerful as an engine-driven system, so I've been amassing parts in order to fit that also - especially as to charge up a big battery bank from flat I'm going to need most of the alternator's output for that.

[Westbay]

Higher output alternator ?

[cobblers]

Those fogstar 300ah batteries are very cheap at £500 a pop! just a couple of years ago I paid £800 for a 200AH one!

Two of them will work really well. I may or may not have ordered one myself.....

[mat_the_cat]

17 hours ago, Westbay said:

Higher output alternator ?

Trouble is any larger, and I'd start to need a multi-V belt to drive it, so complexity starts to spiral. I may yet need to, as to fit an AC compressor I need to ditch the hydraulic PAS pump, so will have to wire in an electric one.

I've managed to fit the new batteries, but only just! Space was tight with the originals as in this old photo.

I've had to relocate the consumer unit the other side of the bulkhead, in the cab.

Next to the new charger unit I've bought, as annoyingly the lowest voltage I could get out of my existing alternator to battery charger was above the 14.6V maximum for the new batteries. Fortunately I had a cheeky offer accepted on eBay

That done I could lower the batteries in, but I have to relocate the relays, amplifier and inverter. Work in progress...

I haven't actually crimped the battery terminal yet; the tape is just to hold it in place until I finalise cable routing.

[mat_the_cat]

Lots of words but no photos...

I've wired up the new batteries, but yet to finish tidying up the fuses and relays, although tested out the charging with mixed results. I'm assuming that the LiFePo4 batteries arrive partially discharged for best storage life, so set about charging them in order to let me calibrate my charge meter. Hooked up to the mains charger, and I've hit a peak of 6 and a bit Amps, which is next to useless. Reading the manual it suggests that if there's a short circuit, it drops the output current to 25%. Which ties in with the expected 25A output.

I reckon the internal resistance is so low that the charger is seeing it as a short, so looks like I need a bigger charger  I then tried charging it via the alternator to battery charger. I'd read a few dire warnings about this, as it doesn't directly control the output current into the battery. Rather it seeks to get peak power from the alternator (at whatever voltage that may be), then output as much current as it can at the selected charge voltage. With LA this is governed by the resistance of the batteries, which increases the closer they are to full. But with lithium lots of people say that this will burn out your alternator; indeed there is even a video of a test bench alternator smoking under load. (Although the channel is from a manufacturer of lithium chargers, and they admit to removing the BMS from the battery in question...)

Hooked it all up, and I'm seeing a charge current of between 55 and 85A. It seems to be varying it depending on the current demanded by the vehicle electrics such as headlights and blower motor. But also appears to be a higher current shortly after startup, so I think it's also throttling the output back based on alternator temperature, as there is a sensor I'd had to fit. So it looks like the alternator will be pushed hard all the time, but seemingly not in an uncontrolled way. It's still sucking up the amps after 90 minutes of driving anyway!

I'm actually quite enjoying the chance to redo the wiring, as additions (of varying quality!) have been made over the years. Now is my chance to do a better job.

[cobblers]

They come at about 30% charge - I put 200AH into mine when it arrived.

I've still got that sterling DC-DC here if you need it 👍

[mat_the_cat]

Thanks, but it's the mains side of things I need to sort I reckon - seems like the alternator side is working satisfactorily in that it's able to cope even when both are fairly discharged. Although from what I read, I'm expecting the same sort of charge rate all the way.

Need to go on a long drive somewhere!

[cobblers]

yeah, they will charge at the same rate til they are about 99% full, you don't get the exponential tail off like on a lead acid. This one took 30A from the charger for about 6.5 hours til the voltage reached 14.2, then it tapered down to zero over the space of about 15 minutes. Once charged, the battery will continue to pull the occasional 5A "gulp" of power as it balances the cells internally. Can't recall if I said it earlier but there is no benefit to charging these to 100% very often at all - if you can limit "bulk" charging to 13.8V-14V then let the solar do the rest you'll get the best life out of them. But we're talking fairly insignificant differences so it's not worth mithering over if it's not convenient

[mat_the_cat]

I do the same with my phone battery, but it will seem strange not to have that nice 100% showing on the meter! Obviously the BMS will shut off at 100%, but I'm not sure of the effect on the alternator if I isolated the batteries from it say at 80%. I will do though when leaving it on trickle charge over the winter.

[mat_the_cat]

I managed to score an 80A version of my existing charger, which being of similar dimensions fitted neatly under the passenger seat

Old versus new:

The 3 outputs wired in; two are doubled up to prioritize the leisure batteries, and the third tops up the starter battery if required.

This gives me 70 amps or so to the leisure batteries, and I assume the remainder to the starter battery.

I've run the heavy current items from the battery via a distribution post, and from that I've run a wire to a low current fusebox. I had some moulded in fuseholders, which act as a main fuse for all circuits in the event of a short on the fusebox itself for example.

I've done the same with items powered from the starter battery, hence the two wires above.

A quick relay test with them in the new position shows all working. The LEDs in them show I'm getting voltage across the energising coil, which is useful for fault-finding.

 

To mount the inverter and amplifier, I needed to make up a support piece. As there is various bit of wiring already in place, it couldn't be a simple shape as it wouldn't then be possible to move it into position. There was a bit of trial and error involved!

It was jiggled in place for hopefully the last time, and the amp & inverter wired up. All fits surprisingly well!

I still want to fit an isolator switch, but otherwise done I think. I've added a switch for the AC to the back of the van, as once I've fitted the engine-driven system, I don't really see us using the original system whilst on the move. All systems go!

Last job was making up a new lid, as the previous one was in two sections with a central support, which had to be removed to fit the new batteries in. This meant I had to make a lid from thicker ply, which can span the full length of it.

[mat_the_cat]

I say complete, but...

When I initially did the conversion it was fairly simple electrically, the only thing unusual for the time was the fitment of a changeover relay between mains input, and the on-board inverter.

Since then bits have been added, notably a fixed battery charger, and AC running via its own inverter. If I fed the charger via the inverter I'm not really sure what would happen but suspect I'd not generate perpetual energy. If I fed the AC's inverter from the existing inverter, it would assume the mains was hooked up, and try to run on the modified sine wave input instead of its own inverter. Also not good.

So I added a fused RCD directly from the mains hookup before the changeover relay, and powered the charger and AC from that.

It's perfectly safe IMO, but I'd rather have all mains routed via the consumer unit. That was it's clearer that everything is isolated, rather than someone shutting off the CU to find that the charger is still live. In reality it's unlikely to be anyone else doing that, but you never know.

So what I plan to do is fit out a consumer unit with 2 double pole RCBOs, one fed direct from the mains, the other from the changeover relay. Something like this.

The other benefit is that I'm picking up a little bit of work on people's campervans locally, as garages understandably don't want to work on the domestic electrics. So having a sensible installation enables me to demonstrate it and hopefully show I know what I'm doing. That part of the system I don't really want to show off!

I suspect most new installs will use a combined inverter/charger unit, which simplifies the wiring somewhat and allows seamless switchover between power sources. But that seems unnecessary expense for me, plus the AC would still need a dedicated inverter anyway.

[mat_the_cat]

*Now* it's complete. I think...

I've added an indicator to show if the incoming supply is reversed, also indicators on each circuit to make it clear that stuff may still be live without a mains connection.

The only slight reservation is how well the RCBO will work with the inverter. Neutral isn't tied to earth, but instead is 115V below. So in the event of someone touching either conductor, it should cause a L-N imbalance and trip the RCBO. Makes sense to me, but a lot of the online advice says it's safer NOT to earth the inverter. I will test it with a plug containing a resistor from L-E I think. My suspicion is it won't trip until 60mA fault current though.

Lastly a quick vid of the Sterling charger starting up. Not that I'm impressed by flashing lights or anything...

 

[Noel Tidybeard]

mr o'reily didn't like his sterling

 

[mat_the_cat]

On 28/11/2024 at 19:34, Noel Tidybeard said:

mr o'reily didn't like his sterling

 

Interesting. I've not used a DC-DC charger (more accurately a battery to battery charger, but everyone calls them the former now) but a couple of alternator to battery  chargers, both from Sterling although neither new. Obviously they too are DC-DC chargers, but you disconnect the alternator output from the starter battery, then allow the charger to manage the charging requirements of both sets of batteries. There's no *direct* control over the charging current, other than the available output from the alternator, so a DC-DC charger is probably kinder to the alternator. But this will charge faster, as it's basically taking all the available power from the alternator until the batteries are full.

The earlier version I had was more audible as in a fan would come on under heavy charging loads. Although not possible to tell over the road noise, only whilst stopped at idle. This one must be more efficient (or the fans don't work 😂), as I haven't heard it at all despite it outputting 80-90 amps for a good while.

The other point about a pure sine wave inverter being more efficient, my understanding is that inductive loads don't work well on a modified square wave, and hence will be less efficient - but on more resistive loads the pure sine will actually be less efficient! A quick Google of specs suggests 90% for a Durite square wave, and 85% for a sine wave. It may well be that the inverter he's installed is more efficient (although at twice the capacity I'd expect the quiescent current to be higher...) but I'm far from certain this is usually the case.

On that subject I've checked the RCD functionality with the inverter, and it doesn't trip!!

It looks as though I'll have to tie neutral to earth for this to work, but unsure what effect this will have on the inverter.

[Sunny Jim]

Admittedly it was 20 odd years ago and the technology has obviously moved on but when I had inverters in my live-in truck they were always wired with a neutral-earth link and then a 10mm earth cable to an earth spike in the ground for RCD to operate effectively creating a TT system.

[mat_the_cat]

Only just seen your reply Jim. My worry is that seeing as L is +115V relative to earth, and N is -115V, if I create a N-E link then I'm going to get significant current flow! I've checked with a test lamp wired between L and E, and this does cause the RCD to trip, so I suspect the lower voltage just means that the test current on my RCD tester is insufficient to trip it.

I've added a further refinement to the charging system now, as I was just a little worried about constantly running the alternator on the edge of overheating.

So I've fitted this Victron unit between the charger and batteries. It works by using the fuse as a shunt, and by changing the fuse value it limits the charge current to 90% of the fuse capacity. This should limit things to around 70A as it stands.

[cobblers]

FYI, I tested my battery with a fixed 170w load:

Only 299AH! I demand a refund 😂