Stage 1 V8 questions.

[greenmeanie]

The vacuum actuator is the silver mushroom thing the tubes attach to on the side of the gearbox. Inside it has a diaphragm that is attached to a rod. This is the rod we're talking about. When you pull the knob in the cab up the vacuum sucks on the diaphragm and pulls on the rod to move it. The rod is inside the metal housing behind the actuator. It pushes or pulls on a selector fork that slides a lock up dog clutch to lock the shafts together in the center diff.

If you unscrew the switch and look down the hole you should be looking at a rod with an anular groove cut in it. This is the rod. IIRC the pin in the switch normally rests in the groove when the diff in unlocked. When you pull the knob and the rod moves the pin in the reed switch is pushed upout of the groove which pushes it back into the switch which closes the contacts.

Probably the easiest way to check the center diff is locked is to pull the knob up, roll forward 10 metres or so at low speed to give it a chance to line up and lock. Put the handbrake on and jack up a wheel on the front of the truck. Try spinning the front prop. If it won't spin your locked.

If you've got the switch pulled out you can also just look down the hole in the actuator housing and see if the shaft has moved so you can't see the anular groove any more.

[Josh NZ]

Ive just come back in from the garage, and im more confused than ever!

Unscrewed the switch on the actuator, and saw the mechanism. Started the truck up and proceeded to engage/disengage diff lock. The little rod moves smoothly in and out. I can even see the mark where the switch has been contacting the rod and it doesn't touch it when its disengaged. So now im thinking its electrical.

Basically I tested the switch and light and got 14.8V at each. Replaced the ground cable just to be sure it wasn't broken, and still the light is on!!

Another strange thing is that if I touch the body of the bulb carrier to the centre dash thing, it lights up. Does that mean that my whole centre dash thing is live and not grounded instead? It does it for the brake light bulb carrier as well.

A rewire of the switch to bulb system perhaps?

[Josh NZ]

Anyone?

Its still driving me bonkers! (and around town too)

Josh

[Gremlin]

Just a shot here from what i read, i believe the bulb is on a live feed all the time and the it is negatively switched at the gearbox. So if you get the wire from the loom and touch it to earth the bulb should light up. Or that's what i think.

Now from what i gather is the bulb is always on? so you must have the wire going to the bulb earthing somewhere to the body or chassis.

G

[Josh NZ]

Hmm yeah I see what you're saying grem. I will run a jumper wire and see what I get then if it sorts it, I will replace the old one

[Josh NZ]

Thread revival!

Thought I would just keep posting up on this thread so I don't clog up the section too much.

Still haven't sorted the diff lock light but the trucks been off the road getting a bit of a rebuild.

The alternator died while driving one night which got me thinking I should sharpen the old girl up. So an order to paddocks, land rover parts NZ and an auto electrician visit ensued. It's been around a month since I last moved the truck, and in that time it's had very little fuel in it.

I go to start it with 10L of fuel today and no joy. Full choke, cranked the bloody thing until the battery went flat!

So, I changed the fuel filter (which in fairness looked as old as the truck itself!) and tried again after recharging the battery. Nada!

Have i blocked the fuel lines with crud? Or is there something else I should consider?

Josh

[disco2hse]

Is it firing at all? Have you checked spark? What are the plugs like?

For the light, have you checked that it is properly earthing? The negative earth connects down by the actuator. If the light is correct then it will only light up when the diff lock is actually working. The best way to determine that the diff lock is working is to lift a wheel and turn it. If the diff lock is working, then the wheel will not turn.

[Josh NZ]

I'm not getting anything at all, just as if the plugs aren't even there. I'll check the coil/HTs etc and just make sure I haven't knocked anything

[deep]

A really good start is simply to lift the distributor cap, turn on the ignition, and flick the points open and shut with a screwdriver. If the ignition is live, you'll see a little spark. Work your way from there. The Rover v8 seems very prone to flooding if you use too much choke on those Strombergs. I think full choke is designed for Siberia...

Don

[Josh NZ]

So I could have flooded it horribly? Would a tow-start in gear get it going?

[disco2hse]

So I could have flooded it horribly? Would a tow-start in gear get it going?

Probably not, if you have drenched your plugs you will need to pull them, clean them and possibly reset them. If they are too bad, you probably need to replace them. If you do, try replacing them with hotter plugs (recommended is BPR5ES so try BPR4ES).

Have you checked the spark yet? Easiest thing to do and least amount of effort required.

[Bowie69]

You can try putting th eplugs in the oven for 20 minutes, fitting and giving it a go, but as above, check for the basics first, spark and fuel.

[Josh NZ]

Pulled a couple of plugs last night. They are soaked in petrol and covered in hard black carbon. Time for new plugs I reckon. I'll check the spark tonight

[deep]

When you have your clean plugs in, try starting with about 1/3 choke to start with. All being well it should leap into life immediately...

Once it's running, push that choke in within a minute or two. Unless you get late snow. I was down your way yesterday and that didn't look likely!

[Josh NZ]

Damn... i'm back!!

Left the carbs to drain for a few days and tried again with a little bit of new fuel. Started up no sweat! Ran a bit lumpy and smoky but evened out after revving it up a few times. Waited for it to get to temp, took it for a 50 metre drive and it was horrendous! Backfiring, hesitating and being very reluctant. Seems like the choke is stuck on, but the linkage etc are free of any jams, or stiff movement.

I tried to reset the choke by slackening the nut on the carb off to release the cable, and re tightened it. Now the truck wont start again and I don't want to flood it again. Its 2 days away from losing its WOF and I desperately need it driveable + super reliable as it will soon become my sole daily driver, and long trip vehicle. I am very tempted to send it down to my local LR specialists!

I'm guessing my carbs need balancing, choke definitely needs fine adjustment and it probably wants a good dose of new fuel plus a good drive. But I need to make sure its not going to spectacularly die on me! Dash pots are full, Ignition produces a nice fat blue spark so no probs there.. maybe timing as well?

Any other suggestions that I should look out for?

Josh

[disco2hse]

Timing or stuck valves or stuffed lifters.

[Josh NZ]

I hope not alan! Do stuck valves free off with use? I'm calling the specialists on Tuesday to see if they've time to look over it and see whats going on first and foremost

[deep]

I had that problem when I got mine. It was an issue with the choke but I can't remember specifically. If you get to that, find a manual or diagramme of what the carbs should look like in detail, strip and clean and carefully reassemble and you should be ok.

First, though, there are obvious things to check. The diaphragm rubbers can be a problem but give almost the opposite symptoms, however they are cheap and straightforward to fix. Also check the oil in the dashpots is very light viscosity, not something too gooey (though engine oil works acceptably). Are the pistons in the carbs rising and falling properly? Check by taking the air cleaner elbows off and gently lifting by hand. Do you have a sticking float needle? There should be a return fuel line - is that blocked. Also, that air intake isn't blocked? I recall it was non-standard. Has a starling nested in it? You're either not getting enough air or getting too much petrol. Try the air first (simply disconnect the extra plumbing as a start...). A few things to go on. Good luck!

Don

[disco2hse]

Good suggestions with the carbs. Attached is a manual for tuning Strommies.

I forgot about the diaphragms. They need to be replaced almost yearly (the chemicals they put into petrol now seems to eat them really quickly). I have SU's now and much less regular maintenance on them.

I typically used light machine oil in the dash pots until they started leaking too much, then I'd use heavier grades. The heavier the grade of oil you use in the slower the action of the plunger (on acceleration and de-accelaration).

You might want to check the vacuum advance on the dizzy too.

Tuning Stromberg CD Carbs.pdf

[Josh NZ]

Thanks Alan and don! Sometimes I really wish there was someone knowledgeable who lived down the road haha!

[Josh NZ]

Well, as of yesterday the LR specialists have my stage 1 in their workshop. I got a call yesterday from their series guru who had asked me if he could personally undertake the job when I rung up, just to give me a heads up on what his thoughts are regarding the trucks state.

He said he took it for a drive, and got the same symptoms as me: Backfiring, poppling and hesitating. Then when he went to start it to drive into the workshop, it really didn't want to go. He has a suspicion that the engine is down on compression but will be performing a comp test to double check. He also informed me that the spark plugs are absolutely covered in soot and the engine is running massively rich, which I thought was the case in the first place.

I would have thought, if the engine was low on compression it would have driven like that before I laid it up for a couple of months..? As it started and drove pretty well minus a few slow starts here and there. Surely laying it up wouldn't have accentuated the problem.

I'm considering just biting the bullet and go for a replacement camshaft, uprated timing chain and gears and tappets. He is ringing me on Tuesday to give me the full report on the truck and then I can decide what to do from there. I would atleast want him to get the carbs balanced, get the mixture sorted and give it a bloody good service (Gen leads, dizzy cap, points, condenser, rotor arm, plugs, air +oil filter and oil change seeing as its there) and see where that leaves it.. V8 are fairly common in NZ but people still ask stupid prices for motors etc so I would be more inclined to get the current motor better before considering outsourcing!

Any V8 gurus care to advise? The truck will cover some fair miles in 25-30 degrees during the summer so I ideally would like to be in good fettle!

Josh

[disco2hse]

Info for a cam to suit.

http://www.stage1v8.org.uk/phpBB3/viewtopic.php?f=6&t=1544&p=9092&hilit=crower#p9092

[Josh NZ]

Thanks Alan, great info! That'll keep me busy for a while

[deep]

Hmm. Cams don't just wear out overnight. It's more a process of quietly grinding off the lobes over time, due to fine particles getting embedded in the followers, I believe. If it ran okay before being laid up, it's not a camshaft problem. I ran my old motor with a knackered camshaft for years (poverty is no man's friend, it's alleged). It wasn't powerful but it ran well enough to keep up with traffic and wasn't sooting up plugs.

It's not a bad idea to have a specialist sort it out (what price sanity?!) but a good specialist will be methodical and will go through the potential problems systematically. Actually, with the Rover V8, it isn't too hard to take off the inlet manifold and have a look at the cam directly, before spending too much. Having said that, high mileage cams seem to be worn as a matter of course. However, a lightly worn camshaft will easily get you through the summer (you'd be stunned if you saw how much my old cam was worn down). Sort your carbs out first and then have a think, would be my advice. It's easy just to spend money. Once you start, it can mount up very quickly (water pump? bearings? rings? valves? etc. etc.).

[De Ranged]

I'm with Don (deep) on this buy a haynes manual and a cheap multi-meter

Mechanical things dont brake because they get parked up lol, get your carbs balanced, if you think you can manage it strip and clean them before you get them balanced..... then my advice would be weak spark, start with your leads (easiest), here is a trick that wont be in the haynes book at night or in a dark shed crank her up and look for any sparks from leads, coils etc earthing out

as far as down on compression.... just ask your specialist what the compression ratios are for the sufix of motor I've been told of 3 different compression ratio's from factory with the 3.5's there are little tweeks to the block that tell you what one was what, sorry it has been a while since I had my rangie I cant remember what they were.... but I'd suggest asking your specialist, just to see if he does know his stuff lol

as for price of motors last one I sold was a complete runner for $250 on trademe they are the cheapest V8 you will find if you want some thing flasher than the 3.5 then you'll start paying