Wouldn't want to go far and it completely break. If you're not going out much due to lockdown it could be the ideal time to arrange a date with insurance windscreen fitters, they might not be as busy as usual due to people not using their cars so much, or if they're busy (maybe they get busier with cracked screens this weather) and mess you about changing the date of an appointment you won't mind so much if you don't have any plans anyway due to lockdown. Any down sides to fitting a windscreen in cold damp conditions? If it's not an inconvenience it's a bonus... new completely pit free screen with fully working electric heating.

Would it help to take the plugs out? Thinking it will crank faster so oil light will go out quicker while there won't be as much weight on bearings in case there is no oil pressure.

A mate used to have a race spec engine from a 70's 3L Capri in a mk2 Escort, it had a manual oil pump he'd pump a few times before starting the engine. Could anything like that be plumbed to the oil pressure sensor port to get oil around the engine and speed up the time it takes for the oil light to go out next time you time cranking?

I used to rebuild my own alternators, there was a local firm called Start & Charge in Grimethorpe. He kept all the brushes and bearings in stock, if you turned up with your alternator would identify which bits you needed, sell you the bits for a couple of quid and tell you how to do the job. Don't know if they're still there.

Some will have heard my story about having an alternator fail on a bank holiday weekend when me and my son decided to go and explore Scotland? No chance I could get the alternator fixed or a replacement on the bank holiday and I knew I could fix it for a couple of quid back home... so I bought a generator, wired it's 12v output to a cig lighter socket and drove all the way home with the genny powering the car electrics, no heater or radio and only sidelights on.

Gilbertd wrote:

It's looking more like the figure given by OBD2 standard and displayed by the Nano, is calculated differently to how Land Rover calculate it.

I wouldn't be surprised at that. What diagnostic gear do Landrover use?

You'll have to remind me if this is Bosch or Gems, I probably don't fully remember intake ducting arrangement for Gems but all air including IAV passes through the MAF on Bosch(?) and I seem to remember (though now expect to be corrected) it does on Gems? Gas entering downstream from the MAF is still gas, doesn't detract from the air the engine needs.

On quite a few P38 LPG conversions, and in fact on quite a lot of other vehicles too, I have seen engine load decrease at idle running on LPG compared to petrol. Some of this can I'm sure often be attributed to new LPG injectors supplying more equal cylinder to cylinder mixture than old/worn petrol injectors but I think there's a bit more in it than that because the same happens on some engines even with petrol injectors known to flow exactly the same - I believe it's related to the difference in stochiometric ratio. Another advantage (in some cases) of a mixer over injection is that if there's any difference in airflow cylinder to cylinder (which can effect cylinder to cylinder mixture in the same way as worn injector flow rates) a mixer will see that each cylinder gets the same/correct mixture anyway.

Most metric live data readings use grams per second as the unit of measurement for airflow, 18Kg/hr equates to 5 grams per second which seems about right for a 4L engine.

Maybe if you lightly touch the throttle in D the load reading will increase, or maybe it will see you're on the throttle and load reading will change to an 'out of idle mode' (my term hehe).

For most intents and purposes P is the same as N except P brings in the parking pawl, same load on the engine anyway. But maybe passing R causes a momentary ignition timing retard that could see the load reading blip positive a little (idle is less efficient with retarded timing but could make for less harsh gear selection)?

For sure the engine isn't running at 28% of power producing or airflow/fuel using potential when it's just idling even in D with AC on and the alternator causing maximum drag. Doubt a normal calculated load reading would reach 28% even if it were a manual labouring the engine flat out at 1000rpm (e.g. high gear low speed uphill).

Load seems to be calculated differently by different vehicles/ECU's. It's often loosely related to the maximum expectation of pinj x rpm, or max expectation for airflow. This of course means that even at full throttle if rpms are below the torque peak calculated load will be less than 100%.

Most OBD systems on most vehicles reckon calculated load is about 3% or so at warm idle. Iirc (but I forget what OBD readers I've used for this) I've seen calculated load much higher than that 3% at idle on P38s.

The calculated load figure isn't a reading I'd normally take much notice of. A manifold pressure reading at idle is a much better pointer for idle efficiency etc. The Rover V8's do seem to idle with a bit more manifold pressure than the average engine, I put this down partly to the cam and valve gear setup compromising a bit of bottom end charge trapping ability to gain a bit more top end (rpm) charge trapping ability.

On some ECUs OBD readings seem to change to a different kind of mode at idle. Maybe the 25% reading reflects the engine could only shift 4 times as much air at idle rpm if the throttle were opened? Does the figure increase by a lot if you put it in drive and turn all the electrical gear on?

Happy New Year...
A strange time to be online but everyone's in bed and I'm bored with the TV, might as well set the ball rolling. Hope for less Covid this year.

Will it depend on whether the birthday is counted as midnight tonight or the time of 'birth' on the 29th?

I disregard reviews on a firm's own website - a firm could write anything it wanted on it's own website, good reviews likely to be from the boss himself or his friends, bad reviews likely to be from competitors.

Some garage reviews and recommendations can be a bit useless anyway - customer1 might go for brake pads changing and be very happy, he might recommend the garage to customer2, customer2 might go for engine diagnostics, the garage who do great simple straightforward mechanical servicing/repairs work might be crap at engine diagnostics.

There are many charlatans working in fields related to vehicles diagnostics, some of them believe their own hype, if they don't believe their own hype they must set out to con customers from the outset.

Or even a round head machine screw? Arguably neater than a bolt head but still no chance of being ingested.

gordonjcp wrote:

I guess if you use a grub screw you should stick a bit of thread locker or something on, so it definitely can't go all the way through if it rattles loose and get sucked into the engine.

Yes, some suppliers sell 'injector hole blanking screws' which are really just grub screws, I wouldn't use a grub screw because there's potential for it to be ingested by the engine, a bolt head cannot be pulled through. A bolt (set screw) will be too long but can be cut short so it doesn't affect airflow.

dhallworth wrote:

I’m going to order a little grub screw rather then using a bolt with a hex head on it as it’ll be neater.

I wouldn't be able to sleep if I did that on a customer vehicle.

Reducer water flow direction doesn't matter if the reducer is below the tide line (you get the gist) when the engine is turned off. Best not to fit a reducer above the tide line but if it is it is better if the intake is at the bottom as this will keep the water channels full (as opposed to an internal waterfall) and lessens the potential for airlocks in the reducer.

dhallworth wrote:

Thanks Simon, I forgot to put .jpg at the end of them so was probably correcting that as you were reading.

So I should be good just to block off that port in the inlet manifold?

David.

A coincidence we're both on forum at the same time.

The pics are what I expected.

Yes absolutely.

The pics aren't working but I understand. Yes that will work fine.

Edit - Strange, the pics are working now.

Smiler wrote:

Which means that when I finally get my Scimitar on the road it should feel like a rocket ship!

My mate dropped a Rover V8 in a Reliant car years ago, not a Scimitar but a Robin lol.

I always thought Araldite melted at around 100C ?

On point 12...

An old guy once came to me with a P38 that he'd just paid a firm the best part of £3k to change head gaskets on because they'd done a sniffer test, found HC's in the coolant and the cooling system was being over-pressurised. But after they'd replaced the HG's the same thing still happened.

It had been converted to LPG, in fact the firm who diagnosed failed head gaskets was the same firm that had fitted the LPG system. They had incorrectly diagnosed HG's, I found the real problem was the LPG pressure reducer had a fault that caused the cooling system to be pressurised with LPG. They'd charged him the best part of £3k for unneccessary work that didn't fix the real problem, I fixed the real problem by fixing the LPG reducer for around £100.

Agreed with the above advice.

I haven't been keeping up with this forum lately, occasionally checked in but as I don't own a RangeRover and there haven't been many relevant threads for me to join in on (LPG / engine fuelling / emissions / etc) I haven't had much to contribute.

I don't remember if Holland-and-Holland has diagnostics gear but at least if he doesn't, on Gems lambda signal wires are easily accessible on top of the petrol ECU next to the battery, only need a multimeter to check lambda readings on Gems.

If plugs / ignition are OK and lambda readings are OK, other things that can cause high CO / HC readings are individual cylinder mixtures. Lambda readings represent close to average mixture readings over 4 cylinders but if some cylinders are running richer/leaner than others then high HC and/or CO can result. Things that can cause that are worn injectors and/or valve gear, the former effecting petrol flow, the latter effecting airflow. I have seen many P38s run more efficiently when running on LPG than when running on petrol (e.g. lambda readings correct in both cases but the engine draw more manifold vacuum when running on LPG, which implies the engine needs less air when running on LPG, which points to an increase in efficiency at least for idle conditions) - I put this down to petrol injectors being old and worn, LPG injectors (on a new install) being new and equally balanced in terms of flow.

Different but closely related subject - On another forum (for a vehicle I've LPG converted hundreds of examples of) I've advised many owners that they don't need cats to be intact if they are converted to LPG. These vehicles are prone to failed cats, they have 4 cats (2 at each side of the V6), front cats fail then the debris clogs the entrance to the honeycomb structure of rear cats, preventing exhaust gasses escaping, causing back pressure, back pressure blows some of the (ceramic) cat dust back into engine cylinders where it acts as a grinding paste and ruins the engine. Many owners have had the front 2 cats, rear 2 cats or all 4 cats decored (4 cats only in case of LPG converted), mostly on my advice. Recently an owner who had decored all 4 cats took his vehicle for MOT but didn't tell the tester it was running on LPG, so the MOT tester failed it on emissions. This was a bit of a sticky moment for me as it could have ended with me being slated on this forum but I had faith it would work out OK in the end.. which it did. The vehicle owner then took the vehicle for MOT at another testing station, told the new tester it was running on LPG, it easily passed the emissions test. It could not have passed the MOT running on petrol with all 4 cats decored.

Dear oh dear, I wouldn't be going back to that place for MOT again, or for anything else again for that matter.