each engine revolution doesnt burn a fixed amount of fuel. What matters is power. Lower road speeds generally use less power to maintain, and thus should use less fuel. You also spend less time accellerating, and less waste going into the brakes stopping again. There are some losses ofcourse, and those often become a larger % of the total as the average engine power falls.

Its unfortunately all extremely complex with many factors all intermingling together. Different cars will also vary wildly making the same comparison.

Engines are typically maximally efficient at peak torque wide open throttle, but they dont spend much time there.

Futher, is the justification of those 20mph limits purely emissions based? There are many environmental factors which arent solely about emissions. Usually there are a host of proported benefits including safety and noise and whatnot for instance. Even slowing down cars such that people consider alternatives such as walking or cycling for instance is an environmental benefit. Theres more to "environment" than just emissions.

20 limits are also a bit odd. The residential streets round here are all 20, and tbh its fine. you cant realistically do much more than 20 anyway without it being a bit silly, as there are corners and parked cars and the like. But they are all proper residential estates. They seem to be extending them into places where they are less obvious though, like link roads and inner city roads that are long/streight/open where 20 feels like your literally stationary. It almost makes it worse in those places as you end up with a bigger stratifcation of road speeds. You'll get the vast majority doing 27-30ish because 20 feels too slow, a few idiots blasting at 40, and then someone doing 17mph (cos their speedo says 20), and i think if anything just casuses more anger and bad feeling on the roads.

But then they've spent the past 20 years doing the same thing turning NSL roads into 50 limits, so its probably not really a surprise.

The 60d Thor engine I bought from the scrap yard recently also has unc bolts on the exhaust manifolds, not M8.

I guess these engines are 20+ years old, and are known for head (gasket) issues so it's not entirely unlikely that the heads could have been swapped?

I've also got a ut210e. Does the job!

My gems went thru 4 or 5 fake crank sensors. Each time they failed it would idle but not rev past about 1500rpm.

The wiring plug on mine was just dangling, presumably the previous owner!

Eventually sourced a new old stock genuine part from eBay and it's been fine since.

Seems to be a few different options then...

Gilbert you say removing the glass with torx screws, is that done with the cassette still installed?

Kinda losing the weather now to be pulling the whole sunroof assembly out of the car though taping something over the roof might work I guess!

There is some corrosion appearing on the roof skin beside the cassette so it probably does want some attention. I really hate sunroofs 🙁

Any tips on getting the sunroof panel out? The headliner is out and retrimmed, but I can't see how the sliding panel comes out of the sunroof cassette to retrim that piece?!

The idea of switching to heat pumps for domestic heat isnt to save money, its to stop burning stuff. Seperate issue really. Nox is a problem in big population centres and domestic boilers produce a vast amount of it, hence the moves to ban them, much like similar moves for automotive applications. Hydrogen only looks good from the viewpoint of how we do in now (a pipey-flamey-burny-heatbox), its a horrible solution when you look at the wider picture. Clearly manufacturers of flameyburneyboxes are going to be championing the thing that keeps them in business. Electricity is great because it comes from many sources. your heat pump can be powered by gas, or solar, or nuclear, or wind, or hydro, or diesel, or coal. A gas burning machine can only use one source. Your electrical machine gets cleaner over time as the grid installs more renewables, Your gas burning machine doesnt.

As for the operating cost, its quite simple. A heat pump operates at a COP between 3 and 4. This means it will move between 3-4kwh of heat for 1kwh electrical input. Thus if we want 15kw output, we need say a 5kw heat pump. But it also means we can easily calculate the cost of 1kwh of heat energy. if the electricity costs 30p/kwh, your 1kwh of heat output costs about 10p at a COP of 3, and ~7.5p if you get nearer 4. The exact operating point depends largely on outdoor temperature and humidity.

Gas currently costs about 7p/kwh. So at first glance gas is cheaper. The gap closes slightly when you consider that the boiler isnt 100% efficient and while manufacturers claim upwards of 95% the reality in a house that needs 70c water might be closer to 80%. the high figures are only achieved if the boiler can condense at maximum efficiency, which only happen when the water temperature is within a tight range. Just like a heat pump, if you retrofit a modern boiler to an old property that requires high flow temps, it wont condense properly and wont be as efficient as it could be.

So at 7p gas, 30p electric, you probably just about break even. At some points when the heatpump is running nearer a COP of 4, it'll be ahead, and at other points when its down near 3, and the boilers operating maximally efficient the gas will be slightly ahead. Its disingenuous to simply state the heat pump will cost £1.80 for every hour its on... My Gas boiler can peak at 38kw, so based on 7p gas it consumes £2.66 for every hour its on. But physics doesnt work like that. The heat input is equal to what comes out the other end. Wether its a gas boiler or a heat pump, the heat required to heat the home is the same. Neither system will run at full power continuously, they'll modulate their output to match what the radiators are extracting from the water. Thus the important figure is what it costs to produce that heat.

One advantage going electric is you can use time of use tarriffs, to shift some of that heating load. A friend of mine has a heat pump and an underfloor heating system. The pump runs over night off peak, consuming electricity at 7.5p/kwh and heats the floor slab. The slab then warms the house throughout the day. Clearly not an easy retrofit, but you can do similar with your hot water heating for example, using the heat pump off peak to heat the water tank. Some installations also have a large buffer tank for the heating, so again you can heat the tank cheaply overnight, and then pump the hot water out to the radiators when you need it.

The big problem i see currently is massively ripoff pricing. Heat pumps arent cheap, granted. A Gas boiler might cost a grand and a heatpumps more like 4-5 grand. The problem is the installers want to rip you off to the tune of 10 grand for an "easy" job, and or closer to 20grand for a "difficult" job. Clearly nonsense, even when compared to the already rip-off price a gas fitter charges to install a boiler.

My personal approach is pragmatic, i have a functioning gas boiler, and an older house thats needing redecorated top to bottom over the next few years. So as i decorate each room, i'll specify a new radiator which will correctly operate at a low flow temp and meet the heat requirements of each room. I'll also adjust any pipework as i go, to remove the microbore sections etc. This has two benefits, one it means i can run the gas boiler at a lower temperature, improving its efficiency, and secondly it means that a few years down the line, the house will be "ready" for a heat pump when the boiler expires.

Even if the bushes look okay, just replace them all. Panhard and radius arms.

yeah i suspect the P38 manifolds are stainless, which expands a lot more than cast iron. The flange is also two piece. Presumably they've done it for fear of expansion causing problems in the manifold itself.

i'll need to see if i can source a replacement weld-in flexi, but super tempted to just sleeve it. I guess i'll need to use a cylinder head as a jig for welding to ensure it all stays in the right place.

No-one seen this before?

I've started stripping the scrapyard V8 with a view to keeping stuff that might be handy and binning anything that isn't.

I've discovered both exhaust manifolds have a small Flexi joint under the heatshield, and on both manifolds they are distorted and split.

Is this a common problem? My car has what sounds like a manifold leak, and my plan had been to clean up the faces on these ones and swap them in when I do the heads...

Is it worth trying to repair them? Anyone just sleeved with solid pipe instead?

yep, nailed it!

I guess I've done the usual and missed the wood from the trees...

Clamped the lines to the alternator but no current showing there.

I pulled every fuse in the engine bay, no difference.

Eventually I pulled maxi fuse 1 and 4 together and it dropped to 0. (1 or 4 separately didn't change the output)

Realised these are probably powering the internal electronics. Opened the door to start going thru fuses at the seat which obviously kicks the becm on and while sitting there waiting for it to time out I realised the passenger rear interior light button was pushed in...

Pressed it... Waited 5 minutes for everything to go to sleep... 0.05a. Hooray!

So I guess that explains the rapid drain, one of the kids has presumably pressed it on Thursday and it's stayed on overnight.

Also suggests that if 0.35a for 15 hours is enough to flatten the battery that the battery is very likely nearing end of life

I have a load tester somewhere, so next job is test the spares I have to see if any of them are actually decent and then swap it out. On holiday next week though so it will wait till I'm back!

Ok this is becoming a real problem.

Over the last few months the battery has run flat many times. If its left for a week or two its almost certainly going to be flat. But on top of that there are weird exceptions.

For instance this tuesday i jumped into it to goto the nursery, it had sat for about a week, and it failed to start. I jump started it and it drove to nursery (2 miles away), it restarted fine after nursery, then drove to the school (1 mile from nursery) and it restarted fine after the school, then i drove it home. I meant to put the battery on charge to give it a proper top up, but forgot. The wife got in on thursday and said it started fine. She drove it about town a fair bit on thursday no bother. Then on friday morning it was completely dead.

Put the battery on charge on friday evening (current limited bench supply, set to 14.4v 10A) and left it for 24hrs. When i checked it on saturday evening the PSU was showing it was still pulling 0.5A so i left it overnight. In the morning, still pulling 0.5A. So i disconnected the charger and dug out the clamp meter for some probing.

Immediately after opening a door, its pulling over 3A, quickly drops to ~2A. Shut the door and it drops to slightly under 1A for maybe 5 minutes or so, then drops to 0.35A and then just sits there. Even half an hour later its still drawing 0.35A.

0.35A feels pretty high to me? Certainly enough to flatten the battery over a week or two? Thats 8.4AH over a 24hrs period. Battery notionally holds 80ah, so 10 days is enough to completely flatten the battery with that load, and ofcourse it'll probably fail to start before its fully empty, and its probably no longer holding 80ah anyway.

But it doesnt feel like "BECM staying awake"? The BECM seems to draw about an amp when its awake, and you can see that after opening/closing a door, but it fairly quickly drops down to this 0.35A reading.

Anyone else measured what the car draws when off as a comparison?

Any ideas what might be going on? The battery itself might by dying, but that wouldnt explain this continuous load, and i dont want to replace the battery and kill the new one by continually running it flat!

It also doesnt explain why sometimes it lasts a week, and other times it doesnt even last 12 hours!

Gilbertd wrote:

I get sent a Parkers email newsletter every so often and I don't know how, or indeed why, people pay the sort of money these deals cost. £400 a month and up unless you are happy to drive something marginally larger than, and about as useful as, a shopping trolley. £400 is about what I'm spending at the moment replacing my gearbox but that is, hopefully, a once in a lifetime expense. If I was to run on petrol and it was £2 a litre, £400 would buy me 200 litres, or 44 gallons. Even at 20mpg, that's still enough for 880 miles. Not that it would matter as most of these deals seem to be capped at 8,000 miles a year. I honestly don't understand it, if I was spending that kind of money every month I'd expect to be able to drive as often and as far as I wanted.

How many people are prepared to jack up their car and change a brake pad, never mind a gearbox? For most people, a car is essentially an appliance. They want to get in, drive to where they're going with minimal faff. If it breaks, its an expensive trip to the garage, so you want to avoid that (typically by purchasing one new enough, from a main dealer, with a warranty). The mileage cap is almost always adjustable, it just costs more. You are essentially paying the cost of depreciation, and a higher mileage vehicle is worth less at the end of the term and thus costs more over the term. The advertisements want to paint things in the best light possible so clearly pick a lower figure (i've seen many showing 5k!). That said, 8000miles a year is apparently about average in the UK.

If you cant afford a newish car on finance, you buy something old/cheap, but then get absolutely reamed on repair costs. I've known quite a few folk who have run older cars, got hit by a £1000 "MOT" and then went and sold it and leased something new. Costs are fixed and predictable etc etc.

The middle ground is even worse. you buy a 6-8 year old used car for 15 or 20 grand. Its now worth enough that you cant readily bin it if it goes wrong, but its old enough that it inevitably will go wrong, often in an expensive manner.

Morat wrote:

I'd probably be very happy to drive a Tesla and I was interested enough until I priced one up. Eeek. Now I can't see the point. I just don't do enough miles to save any money. Once I start my new job which is 100% WFH then there will be no point at all! If I was one of those people who leases a car and changes every three years because I can't be seen dead in last year's model... then maybe.

I mean some people do just finance a car, be it new or nearly new, every few years. And if your already in that cycle, then EV clearly has massive benefits.

I wasnt in that cycle, but got my first EV ~5 years ago when i realised the money i was spending in diesel every month would pay for the car. Total monthly spend went up very slightly, but i went from driving a 11 year old BMW and having to deal with repairs and maintenance myself, to driving a 0 year old Merc with new everything and a warranty.

A lot of this stuff seems shabolically managed at a government level

A colleague moved into a newbuild last year. The developer was "forced" to install a EV charging point (presumably by the local authority as part of the planning permission?) so had fitted a single 13A socket in the garage with a dymo label stuck on it saying "EV Charging". Personally, fitting the charger itself is unneccesary, but what should be mandated is the circuit and cabling be installed and routed from the DB to the front of the house. That way if someone gets an EV, its a simple job to affix the box to the wall and energise the circuit, rather than having to start bashing holes in the house to run cables.

The government seem to have made the big shiney policy announcement banning ICE, but havent actually tackled the proper day to day stuff that needs to happen. They should have been implementing policy changes years ago around ensuring charging points are installed in all new developments, be that residential or commercial. Some LA's have taken it upon themselves to enforce rules on a somewhat adhoc basis, but it really needs a proper joined up view. Motorway charging provision is also a complete mess, because they allowed Ecotricity to sew up the whole MSA network with exclusivity agreements, and then not put any actual effort into expanding the network. Its finally getting better now as Ecotricity sold up to Gridserve (which in hindsight was presumably the plan all along, get everyone locked in, use money from Nissan and the EU to install the first few chargers, and then sit on it until someones going to buy it out for the big bucks) but they're now behind the curve in effect as sales are exploding and the network hasnt changed in about 5 years.

is there a seperate relay for the pump? worth swapping that to try just incase?

Gilbertd wrote:

In the UK it's a technical term spelt phuqued.

From the clattering I suspect the torque converter has broken up internally. It's too much of a 'tinny' sound to be gearbox internals.

broken flex plate? The 4.6 engine i bought from the wrecker has its flex plate broken into several bits.

The only places round here that still have it are Asda and Morrisons. My commute is 40miles from Glenrothes to Loanhead, and i pass one station in Kirkcaldy (Asda) which has LPG. Even Edinburgh, big city has only 2 locations with LPG and they're both on the east side of the city miles away from where i travel and are both charging £1 a litre.

At least the nearest asda is 73p. Thing is for me the P38 is a third car, used occasionally, and even then its quite a concern. For those using it daily, bad times!