The main body of this article was written by Register member John Holmes who rebuilt his 1978 924 over a period of about 5 years, so much of this text is 1984cc engine specific.
Over time I will add and revise this post - this is where you can help by adding to this resource.[
]
2. In the centre of the rear of the crankshaft there is a small special roller bearing in which the end of the drive shaft fits and operates when the clutch is depressed. Porsche instruct you to use a grade 3 grease for this bearing. It is not possible (or nearly so) to obtain this standard of grease in the automobile industry in the UK. Even the porsche agents don' t have it. The nearest is Castrol BNS grease which is a grade 2 grease, a very high temperature melting grade of grease specially for wheel bearings of rally cars. The closes I could find after talking to the technical sections of five oil companies.
3. Check that the little right angled plastic connector in the oil feed in the rocker box is positively sealed to the pipes. If it leaks then the oil flows to easily and the oil pressure drops. Not a big end but a bit of plastic pipe.
2. The drive shafts are very robust as are the gaiters. If however you decide to strip a drive shaft, take out the universal drives and re-grease it, take care! Note very carefully how the cage for the balls is orientated. It is possible to reassemble the unit with the cage the wrong way round. You no longer have a universal joint! You will know because the unit doesn' t work however, it is quite difficult to take the incorrectly assembled universal joint apart again. You are warned.
and become dangerous. New Porsche pipes are very expensive, made of steel and are difficult to fit. Certainly, you have to drop the petrol tank and the rear suspension. I found a brake company who made brake pipes who stocked the larger 10 mm (3/8' ) and 12 mm (1/2" ) cupranickel piping but no end fittings. I saved the end fitting from the old pipe and had them fitted to the new pipe. The pipes have to be bent very accurately (within about 2-3 mm. I arrange to have the fitting connected to one end of the pipe and the pipe cut over-length. I then very carefully bent the pipe using the old pipe as a master and a bending former of about 75 mm diameter firmly fixed. When fitted to shape. I then took it back (very carefully) to the company who then fitted the other end piece in the correct position. You end up with a very funny shaped section of pipe about three metres long. Bend the return pipe first, as it is the smaller and easier pipe to form.
* PaulHere says:I bought new fuel pipes for my 924 at £67.58 and £80.89 (before VAT) in January 2003
2. The pressure regulators - These are mounted on resilient mounts. Check that the mounts are sound.
are standard Volkswagen nuts with a locking device. With time they rust on the
studs, are difficult to undo and it is possible to break off studs. Buy and use
BMW " brass nuts with new spring washers. These nuts are excellent and make removal of the manifold and front pipe relatively easy.
2. The nuts along the bottom of the manifold are difficult to undo and tighten. If the heat guards under the car are removed from around the front exhaust pipe it is fairly easy to get a spanner on to them from underneath.
3. To fit a new exhaust pipe section always remove the whole of the exhaust from the front pipe i.e.. where the pipe is joined with three clamping bolts. Check the lengths of the new pipe against the old pipe and then assemble to whole of the pipe off the car. Then replace the whole exhaust pipe as a unit. this stops resonance in the pipe due to it not " sitting comfortably" .
PaulHere says: Use new style plastic coated earth leads.
2. The pins on the Volkswagen type plugs situated on the fuse and relay panel become dirty/corroded with time. If pin A12 become dirty the ignition system can become intermittent giving poor starting and on occasions the engine stops (in my case always in the middle of road junctions). Solution: clean all the pins with electrolube or similar electrical cleaning fluid.
3. The wiring to the starter motor is not heat resistant and with time the insulation
becomes hard, brittle and flakes off giving a dangerous risk of fire. Solution: buy and fit silicon heat resisting wire near the starter which will have to be crimped onto the existing wiring far enough away to not be affected by the heat.
4. The position of the distributor is very badly designed. In its normal position the 90° bend of some of the ignition wires actually touch the bonnet and hence are under electrical strain. With time there can cause a breakdown of the insulation of the black 90° fitting which is difficult to find. This causes a short to the bonnet giving misfires and if not rectified can burn a hole in the bonnet! Solution: I haven' t got one, but careful inspection of the bonnet will show if you have a burn. Always check here if you have a misfire.
5. If you have an old 924 (like mine) it does not have electronic ignition. It is well worth fitting one of the pattern electronic ignitions (even those that use the contacts). Lumenition supply a magnetic version. Starting is easier and there is an improvement in acceleration. Note you may have to buy a new set of ignition leads as the voltage to the plugs increases.
6. Plugs - Now that all 924s are getting old the recommended plugs for the car have changed over the years. I purchased a set of platinum pointed NGK plugs from a porsche specialist (not the agent). These after 1000 miles gave me a lot of problems and I eventually wrote to NGK complaining. There response was that no wonder you are having problems they are the wrong plugs for the car.
You should be using a totally different set of plugs which they sent me. Since
then no problems at all.
7. As a professional electrical engineer (with 32 years of experience), I was really unable to understand the electrical drawing for the 924 in the Haynes manual. In addition, as I found later there are some inaccuracies which also do not help. I went to great lengths to obtain a colour photocopy of the original Porsche 924 handbook which I found quite readable and understandable if you understand Volkswagen, and hence I was able to reset up the electrical system of my car. Solution: Obtain colour copies of the Porsche original drawings. It is significant that the electrical drawings for the old VW beetle are available from one commercial supplier in colour.
8. May I advise that if you put in any modifications or new wiring into your car, which you are doing it make a sketch with the wiring and the colour of the wiring used and put it somewhere safe. In three year time when you come to make a change or resolve a problem you won' t remember exactly what you did previously.
9. The Driving Lights - These are wired to operate with the main beam headlights. On earlier cars they were wired so that they always came on with the main beam of the headlights. They are simple to modify as the wiring in the car when supplied white wire strap on the fuse and relay panel between pins G8 and D7. If this is removed and two wires and a switch (a console switch) provided to replace the strap then the driving lights can separately operated.
Over time I will add and revise this post - this is where you can help by adding to this resource.[
]FAQ - PORSCHE 924 - 2.0 Specific
ENGINE
1. If you replace the clutch it is wise to replace the rear oil seal of the engine. This is a big oil seal and it almost impossible to fit without very slight weeping. Solution. There isn' t one, just be extremely careful in fitting the seal. You will need a large circular tool to push the seal in squarely and it should be pushed in far enough to ensure that the flywheel does not foul up on the back of the seal. Sometimes new seals " squeak" on fitting which can frighten you to death at the thought of stripping the whole clutch out so see the seal is correctly positioned.ENGINE
2. In the centre of the rear of the crankshaft there is a small special roller bearing in which the end of the drive shaft fits and operates when the clutch is depressed. Porsche instruct you to use a grade 3 grease for this bearing. It is not possible (or nearly so) to obtain this standard of grease in the automobile industry in the UK. Even the porsche agents don' t have it. The nearest is Castrol BNS grease which is a grade 2 grease, a very high temperature melting grade of grease specially for wheel bearings of rally cars. The closes I could find after talking to the technical sections of five oil companies.
3. Check that the little right angled plastic connector in the oil feed in the rocker box is positively sealed to the pipes. If it leaks then the oil flows to easily and the oil pressure drops. Not a big end but a bit of plastic pipe.
GEARBOX & DRIVE SHAFTS
1. If you have a four speed gearbox it is probable that the resilient mounts for the gearbox require replacing. Porsche now supply a standard one for all four and five speed gearboxes plus a kit for the old four speeds. This kit is a silly price!. If you inspect the old resilient mounts carefully you will find that by welding a plat of the side of the new ones - eureka you have an old mount for the cost of about 50p worth of steel and two welds.2. The drive shafts are very robust as are the gaiters. If however you decide to strip a drive shaft, take out the universal drives and re-grease it, take care! Note very carefully how the cage for the balls is orientated. It is possible to reassemble the unit with the cage the wrong way round. You no longer have a universal joint! You will know because the unit doesn' t work however, it is quite difficult to take the incorrectly assembled universal joint apart again. You are warned.
CLUTCH CABLE
1. The plastic end can break PaulHere says: The pedal end clip is made of plastic and eventually fails - Some difficulty may be encountered when unhooking (and reattaching the new cable) the cable from the clutch end, but this shouldn' t be too difficult.FUEL SYSTEM
1. The fuel system pipe-work from the rear of the car to the filter and the return were originally made of steel.. The corrode just by the rear suspension and become dangerous. New Porsche pipes are very expensive, made of steel and are difficult to fit. Certainly, you have to drop the petrol tank and the rear suspension. I found a brake company who made brake pipes who stocked the larger 10 mm (3/8' ) and 12 mm (1/2" ) cupranickel piping but no end fittings. I saved the end fitting from the old pipe and had them fitted to the new pipe. The pipes have to be bent very accurately (within about 2-3 mm. I arrange to have the fitting connected to one end of the pipe and the pipe cut over-length. I then very carefully bent the pipe using the old pipe as a master and a bending former of about 75 mm diameter firmly fixed. When fitted to shape. I then took it back (very carefully) to the company who then fitted the other end piece in the correct position. You end up with a very funny shaped section of pipe about three metres long. Bend the return pipe first, as it is the smaller and easier pipe to form.
* PaulHere says:I bought new fuel pipes for my 924 at £67.58 and £80.89 (before VAT) in January 2003
2. The pressure regulators - These are mounted on resilient mounts. Check that the mounts are sound.
EXHAUST SYSTEM
1. The nuts used by Porsche on the manifold and first exhaust pipe section are standard Volkswagen nuts with a locking device. With time they rust on the
studs, are difficult to undo and it is possible to break off studs. Buy and use
BMW " brass nuts with new spring washers. These nuts are excellent and make removal of the manifold and front pipe relatively easy.
2. The nuts along the bottom of the manifold are difficult to undo and tighten. If the heat guards under the car are removed from around the front exhaust pipe it is fairly easy to get a spanner on to them from underneath.
3. To fit a new exhaust pipe section always remove the whole of the exhaust from the front pipe i.e.. where the pipe is joined with three clamping bolts. Check the lengths of the new pipe against the old pipe and then assemble to whole of the pipe off the car. Then replace the whole exhaust pipe as a unit. this stops resonance in the pipe due to it not " sitting comfortably" .
BRAKES
1. Original brake pipes are made of steel. They tend to rust by the rear suspension. Replace with cupranickel pipes which are easy to bend and it is possible to purchase a kit to make your own end fitting. The pipes are cheaper and easier to fit than steels purchased from an agent.STEERING
1.Check the collapsible section of the steering wheel shaft. This is in the drivers foot well. With minor shunts this section can become deformed and weakened so that eventually it fails. Very embarrassing.ELECTRICAL
1. The engine is rather poorly earthed. This can cause problems with starting and causing misfires. Solution: fit an extra earth wire from the alternator to the bodywork. One of fixing bolts for the offside strut gives a very neat wire position.PaulHere says: Use new style plastic coated earth leads.
2. The pins on the Volkswagen type plugs situated on the fuse and relay panel become dirty/corroded with time. If pin A12 become dirty the ignition system can become intermittent giving poor starting and on occasions the engine stops (in my case always in the middle of road junctions). Solution: clean all the pins with electrolube or similar electrical cleaning fluid.
3. The wiring to the starter motor is not heat resistant and with time the insulation
becomes hard, brittle and flakes off giving a dangerous risk of fire. Solution: buy and fit silicon heat resisting wire near the starter which will have to be crimped onto the existing wiring far enough away to not be affected by the heat.
4. The position of the distributor is very badly designed. In its normal position the 90° bend of some of the ignition wires actually touch the bonnet and hence are under electrical strain. With time there can cause a breakdown of the insulation of the black 90° fitting which is difficult to find. This causes a short to the bonnet giving misfires and if not rectified can burn a hole in the bonnet! Solution: I haven' t got one, but careful inspection of the bonnet will show if you have a burn. Always check here if you have a misfire.
5. If you have an old 924 (like mine) it does not have electronic ignition. It is well worth fitting one of the pattern electronic ignitions (even those that use the contacts). Lumenition supply a magnetic version. Starting is easier and there is an improvement in acceleration. Note you may have to buy a new set of ignition leads as the voltage to the plugs increases.
6. Plugs - Now that all 924s are getting old the recommended plugs for the car have changed over the years. I purchased a set of platinum pointed NGK plugs from a porsche specialist (not the agent). These after 1000 miles gave me a lot of problems and I eventually wrote to NGK complaining. There response was that no wonder you are having problems they are the wrong plugs for the car.
You should be using a totally different set of plugs which they sent me. Since
then no problems at all.
7. As a professional electrical engineer (with 32 years of experience), I was really unable to understand the electrical drawing for the 924 in the Haynes manual. In addition, as I found later there are some inaccuracies which also do not help. I went to great lengths to obtain a colour photocopy of the original Porsche 924 handbook which I found quite readable and understandable if you understand Volkswagen, and hence I was able to reset up the electrical system of my car. Solution: Obtain colour copies of the Porsche original drawings. It is significant that the electrical drawings for the old VW beetle are available from one commercial supplier in colour.
8. May I advise that if you put in any modifications or new wiring into your car, which you are doing it make a sketch with the wiring and the colour of the wiring used and put it somewhere safe. In three year time when you come to make a change or resolve a problem you won' t remember exactly what you did previously.
9. The Driving Lights - These are wired to operate with the main beam headlights. On earlier cars they were wired so that they always came on with the main beam of the headlights. They are simple to modify as the wiring in the car when supplied white wire strap on the fuse and relay panel between pins G8 and D7. If this is removed and two wires and a switch (a console switch) provided to replace the strap then the driving lights can separately operated.
