Limp home functionality

Limp Home Functionality

Otto's been stranded several times. On these pages you can read how to get your vehicle safely home if (when?) something breaks down.

Please send your own advice to get it posted here - it will definetly prove useful for other break-down vehicle enthusiasts!!!!

The hints & tips below will be rearranged as soon as I have found a way to categorize it...Maybe I'll use the structure on sites contents bar, or maybe divided into symptoms, a more complicated hypertext approach - I'll have to see when looking into the tips coming in.

To be included is also some diagnostic tips specifically attributed to breakdowns/limp home situations.

PAS pump break down

Early signs:

There had been some symptoms for a prolonged period, but I did not attribute it to the Power Steering Pump - I suspected the PAS box with it's power sensitive valve or something. The steering made this humming noise when turning the steering wheel, like Dzzzzz, dzzzzz, dzzzzzzz.This is called steering grunt. Been like that for a year and a half before breakdown (it's reported from other Disco-owners to having run with that sound for several years with no problem). After renewing pump, the grunt has disappeared. No idea whether pump breakdown and steering grunt is connected.

Another (unrelated) symptom was steering sometimes went stiff for a split second (even if new drivebelts were put on) - this was only a handful or two times in a year. 4 months in advance of breakdown, the steering felt stiff at a certain point (turning slightly to right). After a short warm-up period, it disappeared and was perfectly normal. This was steeering shaft Universal Joints binding/sticking (almost) seizing.

Symptoms on breakdown:

On my way to a hunting trip, parking in front of a friends house, the steering suddenly went stiff, the alternator light lit up, and a huge cloud of black smoke came from under the hood. The PAS servo pump pulley was stuck, the drivebelt from crankshaft turned around, and was thus burning its rubbers on the stuck PAS pump pulley.

Limp home device:

On a 200tdi, there are two drivebelts. 1: Crankshaft + waterpump + PAS pump. 2: PAS pump + alternator.

This implies: When PAS pump is stuck, the alternator will not turn, as this is driven off the PAS pump.

So both belts were removed, and a makeshift was made up to give engine cooling. A thin rope put three complete rounds between waterpump and crankshaft, knot on the outside. Alternator was left useless. A rope might be put on the inner crankshaft pulley, but will make friction against the stuck PAS pump, and I did not have too much thin rope - would rather like to have an extra length for the waterpump if that one broke... The vehicle uses something like 10-15 Ah, which will give you light for 3 hours or something. The diesel engine must have electricity to run, because of the stop solenoid on fuel pump. Steering damper was removed to get the steering a tiny bit lighter (I run Bilstein Gas damper). Steering is extremely heavy, so drive carefully. Engine started with jump leads to leave as much electricity as possible on the battery. After a 2 hours nightdrive (using sidelights only for about 5 minutes), the battery was down from about 14,2volt to 11.9volts. To improve range you can run without lights, remove some bulbs, run on sidelights only - i.e. switch off anything not necessary to run the vehicle.

For process of renewing PAS pump, go here.

Things to carry to help you limp home

General stuff:

Keep your Disco stuffed & loaded & stacked with all kinds of tools at any time, oils & fluids as well - the more the better. And please: do not forget rags/towels to clean the mess from your fingers before entering cockpit again..
Keep a workshop manual in vehicle to help during breakdowns away from home. In 99% of the breakdowns you'll be away from home.
Keep phonenumbers for fellow LR Enthusiast in vehicle at any time. You'll need it during breakdowns for diagnostic purposes, for towing, to get the tools you didn't bring with you, or for recovery from the so called "road" you're not supposed to be...
You need 2 pieces of 14mm combination spanners (the nut will often need 15mm or even better its imperial counterpart: 9/16") to dismantle a driveshaft, sockets will be of no help because it's to cramped. Will allow you to drive home with 2 wheel drive and a lump of driveshaft inboard (in case of a broken diff, halfshaft or anything).
Wheelnuts are 27mm. Don't forget something to enable you opening those nuts... Specified torque (steelwheels): 129 NM. Jack w/handle is also useful...
Jump leads and towing straps can prove useful.

Engine and ancilliaries

Don't throw away that old drivebelt!!! When renewing, put the old one behind rear quarter-panel for an emergency situation, and you'll never again get stuck with a broken belt (which of course should not occur if they're renewed at specified intervals). For drivebelt sizes, check here.
A couple of meters of thin rope, will enable you to invent a makeshift drivebelt, for instance when PAS pump breaks down.

Elec-trickety

Some wires and clamps for your wiring loom is useful if Lucas starts playing with you.
The Disco is supplied with a complex electrical system, which will often allow you to drive with partial lights - for instance headlamp RH side only... Study the electrical setup to get an idea of the setup during summertime (which fuses can be "borrowed" formore important purposes? Where are the relays?) - might save you catching a cold in a winter breakdown.
The Disco has the following fuses, which should be carried onboard at any time (fusebox allows lots of spare fuses in it): 5A, 10A, 15A, 20A, 30A
Use a permanent marker on relays etc to help next time your at something: what does this one do? where does the wires come from and where does it go? and what the heck is its job?

John Wright advice that you:

"Always carry four or five of those wire clotheshangers from the Laundry and a pair of pliers. You will be amazed at the number of items held together by these!!!"

Engine problems

Clem Daniels shares this advice

(1) Immobiliser failure with result engine will not start

On the V8 try using a simple piece of wire to connect the battery positive to the coil positive.

(2) Starter motor failure & not possible to push start (e.g heavy sand)

Jack one wheel up (difflock off), select appropriate gear, wrap tow strap around tyre and *pull* to turn wheel, turning motor over.

(3) V8 - running out fuel

Will run satisfactorily on paraffin if available - mix in with existing fuel.

(4) Ignition key will not turn

Remove steering shroud. Using sharp instrument and hammer remove "snap-off" screws holding ignition lock.

Remove entire lock leaving plastic circuit housing. Use screwdriver to start and run car.

Diesel Troubleshooting

This table is stolen from Diesel Injection Service and reproduced here to make it possible to take a full prinout of the "limp home pages" to keep in your Land Rover.

Complaint -------------> Probabale Cause	Will Not Start	Hard To Start	Starts And Stalls	Dies On Deceleration	Runs Rough	Lack Of Power	Black Smoke	White Smoke
Low Cranking Speed	X	X
Incorrect Starting Procedure	X	X
Some or All Glow Plugs Bad	X	X			X			X
No Fuel to Cylinders	X
Plugged or Restricted Return	X	X	X		X	X		X
Insufficient Fuel Supply	X	X	X		X			X
No Voltage to Shutoff Solenoid	X
Shutoff Solenoid Bad	X	X	X
Poor Fuel Quality	X	X	X		X	X
Some or All Injectors Bad	X	X			X		X	X
Incorrect Pump to Engine Timing	X	X				X		X
Low Compression	X	X						X
Bad Injection Pump	X	X	X		X			X
Idle Speed Too Low			X	X	X
Fast Idle Solenoid Bad			X
Air In Fuel			X		X
Governor Binding				X
Metering Valve Sticking In Injection Pump				X
Fuel Leaks at Injection Lines					X
Air Inlet Restricted						X	X
Transmission Shift Points Incorrect						X
Brake Drag						X
Incorrect Engine Timing	X	X					X	X
Internal Engine Problems	X	X				X	X

They have a range of tips, though only a few will be reproduced here:

Engine will not start: Also reproduced from Diesel Injection Service

Engine will not start:

One of the most common diesel complaints is a hard to start or will not start situation. Every detail is important when trying to diagnose such a problem. One should determine if engine temperature has anything to do with the problem, ambient temperature should also be considered. Close attention should be paid to the cranking R.P.M. as well as the glow plug system. Starting problems are often electrical related since cranking R.P.M. and the glow plug system are very critical to getting the fuel to burn. Batteries and the starter should also be a consideration if cranking R.P.M. seems slow.

Once the electrical system is ruled out, air entering the system should be considered, especially if the engine cranks, dies and is then hard to restart. Air can enter the system through any break in the fuel line or through a bleedback condition. To determine if air is the problem, install a clear return hose on the return side of the injection pump. If air comes out it is getting in the inlet system someplace. The injection pump is very seldom the cause for air entering the system. In most cases the fuel lift pump or a faulty inlet line usually ends up being the problem.

Engine problems can also be the cause of starting problems. Low compression or timing problems can start out a hard to start condition. Checking these usually involves special tools but it can save a lot of troubleshooting time in the long run.

Fuel supply and quality should also be considered when searching out a hard to start problem. If the vehicle never starts a fuel restriction may exist. Fuel quality is an important part of getting a diesel engine started. Poor quality fuel may not burn properly leading to poor starting. If this appears to be the problem, adding a conditioner such as Stanadyne's Performance Formula may be just the cure. In extreme cases the fuel may need to be changed out and the system reprimed.

The pump and injectors can occassionaly cause a hard starting condition. If a fuel mileage drop or increase in smoke has been experienced the injectors should be suspect, especially if they have ran 75,000 miles or more. If there is no fuel coming out of the injection pump then it becomes a major suspect. First determine if the solenoid is opening by listening for a "click" inside the pump when the ignition switch is turned on. If no click is heard then the pump needs servicing. If a "click" is heard but still no fuel is being pumped, fuel supply and air in the system need to be ruled out as potential problems. One might try using a fuel lubricant such as Stanadyne's Performance JUNIOR, in case the metering valve has stuck in the shutoff. This will sometimes help weak injectors also. If all of these checks are to no avail the injection pump should be removed and serviced by an AUTHORIZED repair agency.

Randy Norton
Service Manager - 23 years of experience in the fuel injection industry
Lubbock, Tx.

Diagnostics: Elec-Tricks

Chris Dow on the tricks of elec-tricks: series IIa:

So, It's Not Working, Eh?

If you've gotten to this point, stop. Go have a Guinness. You're going to need it. All trade schools teach that the proper preparation for debugging Lucas electics is to drink a pint of Guinness.

Starting with the battery, trace the circuit both physically and electrically. It has been suggested that making your own diagram can be of use at this point. Also, this is where the photocopy of the circuit diagram comes in handy (as opposed to the original). Mark off circuits found to be good after performing the test. That way, if you get interrupted, you'll know where you left off.

Debugging the engine electrics

This is where we attempt to determine why the car won't start. If your car starts, but you're having problems with lights, accessories, etc., skip this section.

Attach the test lamp to the ground terminal of the battery (if you've done a ground conversion, or your vehicle was originally negative earth, then that's the one with a minus sign, if not, it's the one with a plus sign, if you don't know then look for one with a cable that goes to the enine or chassis, or possibly both--that's is the ground terminal).

Checking circuit from battery to starter switch

Now follow the fat cable from the hot (non-ground) terminal on the battery to the starter solenoid, or starter switch (if you have a solenoid, this document doesn't address it's components--other than the connection from the battery to the solenoid, and from the solenoid to the starter motor. I've only done this on my Land Rover, and mine has a switch). There should be two brown leads attached to the battery side of the starter switch, and one white lead going from the 'other' side of the switch to the coil. The switch itself is on the bulkhead (firewall to us yanks) and is between the fuse box and the mixture switch, and just a little below the mixture switch. Test the connection of the battery to the starter switch by touching either of the brown leads with the probe from the test lamp. If the lamp lights up, then this connection is good. If it doesn't these wires are probably causing the problem. See above to determine if a wire is bad.

Checking circuit from starter switch to starter motor

Place the probe of the test lamp on the cable running from the starter switch to the starter motor, then have someone push the starter button. If the lamp lights up and you hear the starter motor, then the switch is good. If the lamp lights up and the you can't hear the starter motor, then either the motor is broken or not grounded.

Checking circuit from starter switch to ammeter

Now check the circuit from the starter switch to the ammeter by grounding out the test lamp on the ground post on the back of the instrument panel, and probing both sides of the ammeter. The test lamp should light up on each side of the ammeter. If it doesn't, then your ammeter is toast, and that is the problem (all electricity to a IIA that doesn't go to the horn, the starter motor, or the inspection light socket goes through the ammeter--which is why it's a good indicator of electrical failure. As a field repair the ammeter may be shorted. This involves connecting a wire to each terminal on the ammeter.

Checking circuit from ammeter to voltage regulator

The voltage regulator is a black box mounted on the bulkhead of the engine compartment with tabs sticking out of the bottom of it that have wires connected to them. If anything in that sentance seems wrong to you after looking under your bonnet, then there is a problem. With the ignition off, the tabs marked AI and A should be hot, and the rest should not. With the ignition on, the tabs marked F and D as well as the first two, should be hot. If D is not hot when the igition is on, then look at the charging light and the white connector from IGN on the ignition switch and the yellow wire in the instrument pannel and the engine compartment. If F is not hot when the ignition is on then you may have a blown generator or alternator, although that is unlikely, so check the connections on it. It is attached to what is commonly referred to as the engine harness, which attaches to the main harness and then goes around the block, behind the fan, and to the alternator/generator/dynamo.

Checking the coil connection

With the ignition on, both sides of both fuses in the fuse box should be hot. If they are not, you may have a bad iginition switch (that was my problem), if they are, then check the coil. When the ignition is on, the white wire on the coil should be hot. When the starter is engaged or the engine is running, the small wire (not the big cable) from the coil to the distributor cap should cause the test lamp to flicker when the probe is touching. If this doesn't happen, you need a new coil.

Debugging the Instruments/Accessories/Lights

This isn't so hard. Here are some things to remember:

The charging lamp works by having current going to both sides, then when the generator/alternator stops generating current it becomes ground, and the lamp will be illuminated.
The oil pressure warning light works by having current going into it at all times. When the sensor senses less than sufficient pressure, the wire leading to it grounds out, leadint to the lamp being illuminated.
The cold start lamp works just the opposite. When the engine is cold, the thermostat isn't grounded, but when it heats up, the thermostat grounds out. This causes current to run from the battery to the light, then through the switch on the bulkhead which is actuated by the choke cable, then to the gound on the thermostat. This lights the indicator.
Turning indicators: If your flasher is mounted like was (vertically), then you'll want to mount it horizontally, so you can see the labels on the spade connectors. Once the harness to the turn signal switch is properly connected inside the dash panel, then you need to make the proper connections in the engine compartment. Be sure you do not confuse the Green/Yellow Oil Pressure Indicator Wire with the Green/White Turn Indicator Wire. This happened to me, and wasn't fatal, as my rear harness was so old, the white on the turning indicator wire was white--it looked yellow to me. It just took me a while to figure out why my turning indicators didn't work The statement above about not hooking up wires unless you know what they do applies here.
A frequent failure point for headlamps is grounding. I ran extra grounds to the body of the rover in the breakfast.

Ezzie: Not translated yet...

- Har alltid med verktøy og en del greie deler:
- Lykt, hansker og vernebriller. Mekkeklær
- Jekk, hjulkryss
- De vanligste fastnøklene, skutrekkere, tang og nebbtang, skrallesett, bladsøker, dekktrykkmåler, kniv og saks
- Tenningsdeler; rotor, stifter, plugger, kondensator, lengste pluggledning, fordeler lokk etc. Lyspære sett. Viftereim, slangeklemmer, pakningsmateriale, pakningssilikon, termostat, ledningstumper og kontakter (og tang), diverse skruer, bolter og muttere, strips, ståltråd etc, viskerblad
- Olje, girolje, bremseveske, clutchveske, frostveske, spylerveske.

Ting som folk kanskje ikke tenker på å ha med seg, men som duger til mye rart:
- Strips, kabelstrips er greie å ha med seg. Leste noen som brukte disse som viftereim. Måtte selvsagt fornye denne med jevne mellomrom, men det gikk. Alternativ til slangeklemmer, henge opp eksos, feste ting, og ikke minst samle ledninger.
- Elefantteip (grå vev teip) Teip og kontaktflater må varmes opp om vinteren for å sitte, men sitter det så sitter det også. Fint til alt, binde opp ting, tette slanger etc.
- Selvherdende tettepasta til radiator etc.