Jocklandjohn

The odd behaviour I've got is an oil pressure gauge that went off the scale suddenly when driving. The gauge is one of three (water temp and oil temp as well). All three are wired with a common Pos and Neg and have been installed and working perfectly for 6 years. The other two were unaffected and giving the appropriate readings. Of course I thought an overpressure in the engine was the problem. However I could replicate the problem with the engine switched off, cold from an overnight parked up and not run. That made me suspicious. So changed the sender. Same problem. Then renewed the wiring back to the gauge. Same problem. Then unbolted and cleaned and reattached the earth straps from gearbox to chassis. Same problem. I then thought the gauge might be defective. Replaced the gauge with a new one. Same problem! I then started poking about in the dash wiring and found that I could replicate the problem on the water temp gauge if I disconnected it from the the common earth it shares with the oil temp gauge. In fact putting the two oil pressure gauges on the kitchen table (well away from the 110!) and wiring a 9V battery to the Pos and Neg terminals on the gauges replicates the problem, with the needle pinging right off the scale in exactly the same manner. I've used three separate 12V batteries - wiring directly to them - two are connected to the vehicle - starter and aux batteries, both earthed to chassis, but the third battery I pulled out of the shed and connected directly using both the old wiring and new wiring directly to the pressure gauge so bypassing the entire vehicle system (except the connection to sender) and I'm still getting the problem. So I'm kind of stumped! Curiously the pressure gauge needle responded to the throttle, when I noted the problem and pulled over to the side of the road the needle went down to the normal position on the scale, but flicking the throttle made it go straight over past the 120PSI mark hard to the edge of the scale. So.......its either a massive overpressure - which doesn't seem to be the case (although I've not had a mechanical gauge on it yet - but the problem persisting with the engine cold and switched off leads me away from this) so...thinking as I'm typing here.....might it be an alternator connection problem? Whatever it is its got me baffled! And I'm on the verge of buying a mechanical gauge and fitting that, but I really need to find out what was causing the issue in case it's going to affect any other aspect of the electrics because I ignored it.

Cheers Red - I've cleaned and reattached the straps from gearbox to chassis, are there any other engine earth points I should be aware of?

Ok thanks Ralph.

Thanks Ralph, that's helpful. I'm trying to sort out a weird oil pressure gauge earthing problem. So why do the gauges (I got Durite ones) have 3 connections - one for Pos, one for Neg and an S (signal) if the S is effectively an earth?

May I have a minor thread hijack to ask - do all the senders - oil pressure, oil temp, water etc work on the same principle as described above? With the wire-to-gauge going to earth through the sender, with the resistence varying according to temp?

Closed cell foam is your friend. Make sure it is proper closed cell, as open cell is a.....er.....sponge and will naturally absorb all the damp and eventually stink. It needs to be glued well to the whole roof surface, using some high-temp adhesive - you can get sprays for this (make sure they are high temp) or use EvoStik - you may need a gas mask or oxygen supply to prevent you dying whilst doing it though! I've done several 110's with it. It is pretty easy to do, although time-consuming. Best done on a warm day when the inner roof surface is warm and dry. On top you can put whatever you want but you can buy automotive carpet from campervan converters that is stretchy so it can be neatly tucked into the corners. I put several layers of foam in the main panels to bring the foam surface up to the level of the top of the roof strengthening ribs then covered the whole surface with carpet. Warm, dry, quiet. Various options - camping mats are widely available. But a better idea is to get a few of you together and put an order in to a 'chemical converter' - the folks who actually make the stuff, and buy a few 8x4' sheets - you can choose your grade and thickness. I paid £100 for an order and that was enough foam to do three 110's with a single layer or two vans with a double layer - that's doing double on all of the roof, and single layers on both sides and the whole rear floor (under ply).

The "dropping back down to normal instantly" is the correct thermorstat behaviour - when it hits the right temp it opens and the temp drops. The "creeping" is when it doesn't properly open, the gauge then appears tardy and the temp stays high as not enough coolant flow is happening. (but of course the temp sender might be duff, but the thermostat is a cheap first fix).

Sounds like the thermostat is misbehaving. Only a few £ and a few minutes to swap. Probably find it makes a huge difference. (buy a genuine LR one - not hugely expensive).

Update! As I mentioned above the van has been running fine, I'd managed to get a good balance of performance and smoke/idle speed. But it was noticeably noisier than before I'd had the pump swapped, and also a big patch of diesel was evident running down the side of the engine and the culprit seemed to be the lift pump. This was a new one put on by the garage when they fitted the new fuel pump, as my old lift pump (fairly new) was knackered, but all they could get was a cheap thing that looked pretty frail. Anyway over the last couple of days reseating the pipes, and replacing copper washers didn't help the leak - it seemed to be welling up around the fitting on the top of the lift pump that connects the pipe from the fuel filter. Had a closer look and it seemed to be weeping from the base of the pipe fitting itself, not the pipe joint. So I ordered a new Delphi lift pump which I stuck on this morning. When I had a closer prod at the one that came off it was obvious its got a defect in the connection which is allowing diesel out (and air in). The new Delphi has transformed the vehicle. The idle is smoother and it pulls cleanly all through the gears, and crucially is much much quieter and smoother than it was. Its a simple fitment a lift pump but as this goes to show, you get what you pay for and I have to say although I was pretty happy with the performance yesterday (although noisy) today its like having a new engine. £20 well spent - thanks Delphi!

Thanks Western. Appreciate those. Think I'll just renew the whole pipe, judging by the state of it, it looks like its been on there for a couple of decades so I guess it doesn't owe me anything!

I've got diesel welling up out of the bottom connection of the pipe from the rhs of the fuel filter (200tdi) to the lift pump. It's either the pipe joint itself or the lift pump which is a cheap and nasty thing but all the local garage had available when they fitted my fuel pump and realized my existing lift pump which I'd only recently put on ( a cheap one) was knackered. I'm swapping the cheap pump for a Delphi, but as the pipes (which have a banjo on top) are £20, I'm wondering is there a replaceable o ring on the pipe union where it mates with the lift pump? I recall seeing a black ring on the end when I fitted the last one but I'm not sure whether its a sealed on bit or whether it can be replaced. Anyone got any idea before I pull it apart?

Aha - I may have solved the problem. Backed off the throttle linkage and the idle screw and gave the throttle arm (on the pump) a good waggle about with a small amount of dry lubricant (pencil lead shavings) and gained about 4mm of additional minimum throttle (ie I could move the throttle arm further back against the threaded stop screw). Seems there may have been a rough spot or something small trapped in the joint and which is now gone and I'm able to reduce the minimum idle by a good amount given that only tiny adjustments make a big difference to fuel delivery. I've now been able to raise the fuel delivery and drop the idle speed to compensate so it ticks over correctly. Just been for a run down the road and its running beautifully, pulling strongly in 3rd and 4th and is now able to actually make headway in 5th without difficulty, whereas before I could barely make forward progress in 4th. Very minor black puffs initially when going under load and clean as a whistle when cruising. Thanks everyone for your assistance - greatly appreciated.

I've just had the same problem. Complete pig of a thing and repairs were useless so I left it and thought I could live with it, but it started to move about and the wiring for the headlights/sidelights started to go off of their own accord (usually in the dark of course!) as their wiring got faffed about by the movement. Replacing it took less than an hour and was well worth doing.

Pump guys totally overhauled the pump, renewed the seals etc and it failed the testing, they had to replace the hydraulic head and it passed the lot, and was delivered with all specs as per Bosch test plan. They're the local Bosch agents with 40 years of doing this stuff for the whole of the north. They flow tested my old pump (the one that came off) to see how far from spec it had been adjusted and they reported that the fueling had been adjusted to give about 20% more than standard. They didn't comment on any other settings being adjusted. Their opinion is that the more efficient intercooler and hybrid turbo I've fitted, combined with Disco (1.222) gearing, is making it less perky on the standard setting than it should be.

Yes that's the adjuster I mentioned that I'd wound back (and the throttle cable too). The adjuster is now back as far as it will go - small screwdriver in slot, wound rod OUT until its got no more adjustment, but still too fast. Not silly fast but way faster than it should be (dont have a tacho fitted yet so cant give an accurate estimate of rpm, but probably 900+). I cannot see any other adjustment except the bolt/slot in the throttle linkage arm I mentioned above.

I hate to say it (but I will as it may save you some bother later) - that approach might not be as effective, as there will still be air-metal gaps between the inner metal and the fabric/insualtion, and condensation will probably form there, then drip into the fabric round the mats and eventually make it very smelly. The absolute guarantee of preventing condensation forming is to make sure the foam matting is stuck directly to the metal and with the adhesive covering virtually all of the surface. I've insulated 110's several times and made all those mistakes on the first couple and had to redo them, but I didn't make the same mistakes on the rest! You can make it easy for yourself and do as I did - cut the insulation into smaller easily manageable pieces say a foot square, and work methodically through the vehicle keeping all the foam joints tight and sealed with a splatter of glue. Once the whole surface is insulated THEN stick some velcro on the INSIDE of the foam mats and attach the covering fabric to it. That way you have a nicely insulated space and the inner fabric can be removed to wash it whenever it needs it, as it will gather cooking and living smells over time. Best of both worlds and really simple to do, with minimal mess.

Mike there's a low-odour EvoStik thats solvent free (link) and this is probably what you need. The other (yellowy) stuff in the red tin is death in a can. I almost knocked myself out with it a few decades ago (in the building trade), and when I used it several years back to stick foam matting to the Land Rover roof I had to take a deep breath, run inside, do a bit, run out, take a breath, run back in and so on until I almost passed out. Then I found the less smelly stuff and it worked pretty well. You can brush it on so its pretty easy to use.

Managed to get some progress on fettling the new fuel pump. With the pump engineer's assistance we upped the fuel screw (small one with lock nut on it) but only a very small amount, less than a 1/3 turn (probably less) and hey presto instant transformation. It now pulls cleanly, a very small puff of black smoke on load and clean running as it settles into cruising in top. I've got third gear back now and more pull in fourth. The old pump pulled well but was pretty tired and this new one is definitely pulling better and running cleaner across the whole range. However. I now have too fast an idle. I've backed off the idle adjuster rod as far as it will go and ensured the throttle cable is slack, but its still running way too fast. Is there any other idle adjustment externally? I note there is adjustment at the bolt in the throttle linkage arm (or whatever its called) - the arm with the spring under it, and a slot in the top with a bolt through it - which is bent at the end and butts up against the idle adjuster rod. Will adjusting this enable the minimum throttle/idle speed to be reduced?

Yes - I've had that happen before (Fiat Panda!).

Cheers chaps. I had the timing belt changed when the pump was swapped. Mechanic who did it is old school, works in a specialist 4x4 garage specializing in Land Rovers and runs his own 200/300Tdi 90. He's been at it for decades so I'm pretty confident that its been installed properly, and he checked over all likely culprits for the laggy running before he let me take it away from the shop. I've just checked the wee 4mm pipe and its all connected, and there's no sign of any other obvious faults. I've just phoned the chap who originally set up the old pump when the engine was overhauled and he's told me he only adjusted the fuel screw and the diaphragm (as Boydie noted) and nothing else.

I'm guessing the combination of increased turbo/intercooler PLUS Disco gearing means I need more fuel. And aye the top cover and screw are painted! Will check the wee pipe tomorrow morning.

Thanks! At least it goes, but being restricted to 35mph on anything resembling a slope is doing my head in!

The pump folks have been helpful (very) but are not prepared to alter it from factory settings 'just in case' which I can understand, they've got an excellent reputation built up over decades (family business) and don't want to compromise that. There is another very highly experienced independent LR garage locally who might be able to tune it for me. This is territory I'm not really comfortable wandering into on my own!

Hi Frax When the van was overhauled 7 years back I had a Turner transfer box and gearbox with Disco gears fitted, and the intercooler and hybrid turbo installed. The engine was inspected (out of the vehicle) - stripped, checked over and put back together by a well-known and respected company, and the lads putting it all back together on the new chassis are also very skilled LR mechanics. They did a good job and it's run well for the last 7 years, and been problem free (apart from bad smoking which was solved by using better fuel). So basically the old pump that was removed had been tweaked to suit the new gearing, turbo & intercooler. I was able to confirm this because the pump overhaulers put the old pump that had been removed on their test bench and established that the fueling had been increased by about 20% from standard. What I appear to have now is too little fuel for the current setup. This reduction in power has only happened since the pump was swapped over, so I cant imagine it's anything else. What are you 'suggesting' it might be if not the pump?

Thanks chaps. I'm aware of the warranty issues, and I'm not looking for a massive ripsnorting vehicle, simply to be able to keep up with cyclists! So I doubt my fueling increase will be overdoing it. Edit. In fact if it's going to involve more than simply tweaking a single screw I'll be looking for an expert to do it rather than start messing about from a position of no knowledge, simply aspiration. (Does that make me a naturally aspirated driver?)