The Peugeot 104by Oliver Webb
1): Looking at the 104. Brief history and description.
The engines fitted to all 104s were of the same basic design; transverse 4 cylinder, alloy, overhead cam with cast iron wet liners giving various capacities of 954cc, 1124cc, 1219cc and 1360cc, no diesels. The engine was laid on its back with the rocker box tucked virtually beneath the scuttle and the 4 speed gearbox placed in the sump. This arrangement kept the engine very low in the car, giving a low centre of gravity and allowing the spare wheel to sit above the engine whilst keeping a low bonnet line. But it did make the mechanic's life difficult due to awkward accessibility (notably setting the tappets and the contact breaker points), and for many jobs (cylinder head and head gasket, cam, timing chain, pistons, con rods and crank, clutch, transfer gears, transmission and differential) it is necessary to remove the engine from the car. However, these units are well engineered and, providing that they haven't been abused or neglected, can easily out-live many of their rivals.
Suspension, independent all round, was by MacPherson type struts at the front and single trailing arms with vertical coil springs at the rear. Some of the higher performance (ZS) cars had anti roll bars at the rear as well as the front.
2): Looking for your 104. Avoiding dead bodies.
The 104, like most pre-205 Peugeots, can rust horribly if neglected. Most will be apparent to even a rudimentary glance, but certain areas demand careful inspection for rot and patch-up welding hidden by thick, recent underseal, most critically around the rear of the car.
Open the bonnet. The flange where the inner and outer wings join corrodes, starting at the front. It is a good idea to run a little magnet over rust-prone spots to discover layers of filler and fibreglass masking rot, or, especially on wings, dents. Also bear in mind that original wings have a good layer of underseal on their insides and when tapped with a knuckle, do not resonate with a metallic bong – said bong equals replacement wing without proper rust-proofing. Rust can also affect the ends of the bonnet catch cross member, then extend back. Front wings rot along their top edges, starting at the front, then extending down to the bumper and the wing/front-valance joint. The headlights can easily be removed to reveal any rot around their mounts - plastic cable-ties or wire securing the headlights are not uncommon tell-tales of broken or rusted mounts. Remove the plastic panel on the scuttle which conceals the wiper motor. This exposes a large void beneath the windscreen fresh-air intake which can fill with soggy muck. Bad rot here is visible at the point where the spare wheel cradle enters the scuttle - try pressing here with your thumb, it shouldn't deflect or crunch. When the floor of this void rusts through water will leak into the cabin behind the dash and trickle down behind the carpet/rubber mat and corrode the floor. Lift out the windscreen washer bottle and inspect the metal behind it – wet debris trapped behind the bottle can rot out the bulkhead unseen.
Open the doors. The sills ought to have a little protruding lip that lines up with the bottom of the door-skin, just above this lip is a seam. If the lip or seam are absent it is probable that some bodgery has happened - possibly nasty cover sills. Examine the point that the "A" post (front door hinge) meets the sill and above the top hinge at the base of the windscreen pillar, it is possible for the "A" post to become detached from the sill and sag, a dropped door can indicate this problem (particularly on 3 door cars which have longer, heavier doors), the hinges themselves tend to last well. A black leather-cloth faced material glued to the inside of the sills restricts visual inspection of their inner faces, but if you are in doubt, grasp the sill in both hands and squeeze it, crunching noises aren't healthy! Dampness, the distinctive smell of mildewed underfelt or pronounced condensation inside the windows is bad news and demands extensive examination. Lift the carpet and look at the front foot-wells and beneath the front seats where the dips in the floor pan can retain leaked-in water, the outermost front seat anchors (held by allen headed screws) can rot out. Check the base of the "B" posts where they meet the sill. Lift the mats and examine the floor, 4/5 door cars' sills are easier to check than 3 doors'. Tip the rear seat forward, a damp or stained rear seat will probably indicate leaks and consequential rust in the area beneath the seat. This area is crucial to the car's strength as the rear suspension is bolted onto the sill here, examine it very carefully. Any welding previously carried out on the trailing arm mounts will be visible here – BEWARE of bodges! The central rear suspension mount is attached with 4 bolts and although less likely to rust, should be checked Rust can penetrate the floor, in the centre, where the seat belt bracket is bolted and the inertia reels can become detached from the sills in serious cases.
Open the boot, lift the mat and examine, in particular, the seams where the boot floor meets the inner wheel arches, also the arches themselves just behind the back of the rear seat and at their rearmost point, common rot spots. Look at the boot floor for dents or distortion through very heavy use - particularly on 5 door cars. Check the area immediately below the tail light lenses and the rear valance at the level of the boot floor join; both are rust prone. The rear-most corner of the rear arches below the bumper forms a condensation/leaked water trap just behind the arch which eventually rots out. The rear arches are prone to rust on all models, particularly the splash guard that protects the top suspension mounting and the pressing which aligns with the bump stop. 3 door cars rot at the rearmost corner of the side windows ("C" post) and the roof above the tail gate hinges - beware cars that have had a vinyl roof or after-market sunroof fitted. Inside the boot you should find the jack and wheel brace.
Starting at the front, look at the front subframe and where it's bolted to the shell - the front is a little difficult to see. Examine the "chassis" legs that run beneath the front foot-wells, if a car has been grounded on rough ground the paint can get damaged leading to structural rot. Examine the jacking points at the front of the car, visible as square holes just below the sill (The correct jack has a square rod which fits into this square hole), this area is a box section and often rusts. At the rear look carefully at the areas where the rear suspension is attached to the sills and centre support in the middle of the car. Rot in the sills near the trailing arms is a very common 104 MOT fatality, it can be repaired but is a bit fiddly. Behind the rear wheels, try to see the condition of the inner arch where it joins the boot floor. Petrol tanks can fail around the horizontal seam half way up, usually at the rear, and the filler pipe can leak if the tank is filled to the brim. A fill-up at the garage will expose any leaks! Use a torch to look at the suspension. Front struts tend to rust out the pan that retains the bottom of the coil spring and the rear suspension (which are not actually struts) rots out the top retaining plate - the latter is hard to see.
Doors, bonnets and tailgates.
Easy to replace and not MOTable, unless rusted into jagged pedestrian-slashing holes, but they are a consideration at £20 + each for good and increasingly rare second-hand items. Bonnets rarely rust, but if they do it will be along their leading edge. Door rot is fairly straightforward; initially bottoms of frames and skins, base of window frames (particularly rear quarterlight), just above catch mechanism and usually around door mirrors, latterly everything made of steel….. Wind down each window in turn, rarely used window lifts (usually the rears) rot and disintegrate and lock each door, including tailgate - the ignition key should lock both front doors. The doors should shut easily without any need to slam them, dropped hinges are fairly rare, but front doors fouling the B post can mean rotten A posts. Clattering noises within the door when it is shut firmly probably point at window lifts or door catch mechanism beginning to fall to bits. Bear in mind that 104s were never as thief-proof as a modern car and the locks, though still working, may well be worn and less than secure. 3 door tailgates rust below the glass and on their bottom edge, 5 door ones tend to lose their bottoms along with their catches.
3): Looking for your 104. Avoiding expensive transplants.
The 2 main Achilles' heels are head gasket failure and excessive cam shaft wear, both are avoidable with just routine maintenance and careful driving.
With the car cold check oil, water and brake-fluid levels. Black tarry oil, an ancient/cheap oil filter, or lack of anti-freeze screams of dangerously inadequate maintenance. The oil filler cap, with its two attached hoses, should not be gummed up with either black gunk or "mayonnaise". Some mayonnaise in winter may be attributed to condensation, not itself disastrous by any means, but it may clog up the gauze filter and breather pipe and impair the car’s performance noticeably. However, water droplets on the dipstick or oil in the radiator expansion tank is a dire warning of shot head-gasket. Start the car from cold. Automatic choke cars used for short-hop journeys tend to foul their plugs and can be hard to start. If when a manual choke is pulled out the accelerator butterfly fails to operate (i.e.: engine revs are too low without additional pressure on accelerator pedal) it is probable that the carburettor top has been removed and reassembled wrongly - easily sorted out. 104 engines should be pretty quiet, tappety noises almost certainly mean a poorly camshaft and big/little end trouble will be audible under acceleration. Clouds of blue smoke on starting probably indicates worn valves and guides. A whining howl, rising with the engine revs can be nothing more sinister than the plastic air-filter box fouling the alternator vanes and when warm an oily pong inside the car may indicate nothing worse than oil spilt when topping up, it can lie on top of the engine and simmer, but check! Gutless performance can be attributed to nothing more sinister than a brake caliper not freeing off entirely – after a mile or two at normal road speeds a warm wheel is a telltale!! New calipers are available for the price of a small house, but second hand/old stock can be got quite readily.
On the 104 "radiator problems" frequently mean "head gasket problems", which in turn mean "cheque book problems". When the car is warm turn the heater on full blast - if it blows cold, there is (surprise, surprise!) a problem. The valve may possibly have stuck (unlikely), or rad-weld may have been used in the system resulting in a gunged up heater matrix – tell tale of a radiator adventure. If it blows erratically hot and cold there are bubbles in the cooling system; probably head gasket failure. On post 1978 cars there ought to be 2 bleed screws - one on the radiator de-aerator hose and one in the carburettor preheater inlet hose, it is very important that the cooling system doesn't develop air locks which will result in overheating. By removing the expansion tank cap and revving the engine for a minute or so, a failed head gasket can be identified by massive turbulence blowing coolant out of the tank's filler. Look for water leaks - antifreeze stains on radiator, hoses, etc. The radiator fitted to the 104 is very large and efficient and it is rare to hear the electric cooling fan cut in. Unfortunately this allows some thermo-switches and/or fans to expire unnoticed and, combined with the car's lack of water temperature gauge, many 104s getting cooked in stationary traffic on hot days. You can check the fan's function by removing the 2 wires from the heat sensor (beneath air filter) on the radiator, and with the ignition switched on, shorting the two wires out - the fan should leap into life. If not, it's either a blown fuse (fuse box is under dash on left), duff sensor or dead fan. If the car is minus its thermostat, somebody's had a go at curing overheating - and failed!
In cold weather a high mileage car may prove reluctant to disengage 1st gear and/or engage 2nd gear at anything over snails pace until warmed up a little, then the problem eases. Synchromesh can become rather weak in old age. A sloppy gearlever is probably due to a little nut and cup-washer working loose underneath the car on the linkages, eventually it drops off leaving you stuck in whatever gear you’re in at the time! Easily fixed, add a spring washer. A stiff gear change probably indicates lack of lubrication to the linkages beneath the car. A heavy clutch pedal suggests imminent cable failure. Awkward, graunchy gear changes when the car is warm are probably due to an incorrectly adjusted clutch - very critical. High mileage cars will often have a fair amount of "snatch" in the drive train if the throttle is paddled, and heavy clonking may indicate a weak or broken engine mount. Drive shafts that are on their way out will clonk rhythmically at full lock and under heavy acceleration, occasionally they can produce a faint big-end type knock at about 45 MPH when coasting on the flat with minimal throttle. With alternate full lock, check that the drive-shaft rubber boots are fitted and intact. There are at least two types of boot which unfortunately are not entirely interchangeable; one type relies on a moulded lip around its inner edge to locate and seal onto the drive-shaft, if the wrong boot has been fitted it will be virtually impossible to prevent it popping off and exposing the vulnerable joint to road grit. Brake shudder from a warped front disc will often destroy wheel bearings - coast in neutral and listen out for bearing drone. Rear bearings can rumble, even on relatively low mileage cars, a worn bearing will drone as the car's weight transfers during brisk cornering. The car should pull up well, the nose will dive a certain amount but she ought to stay true and straight. Pedal pressure tends to be quite firm. A worn out driver's seat or worn smooth steering wheel will betray a replacement speedometer - 104 interiors tend to last well!
104s display more body roll on cornering, compared to many modern cars, but they should handle very neutrally with understeer gradually becoming apparent if pushed to the limit. At the extreme limit the inside rear wheel may lift off. Soggy handling or a difference in agility between quick left and quick right hand cornering is likely to point at a collapsed or badly corroded outer rear trailing arm pivot, this is also accompanied by a heavy bang as the rear wheel drops into a pot-hole and the car’s weight comes off the wheel temporarily (but not necessarily on bumps). Bump-steer suggests a problem in the geometry of the suspension – quite possibly due to a welded up rear trailing arm outer pivot. Alarming sudden lurches mid corner, oversteer and pulling to one side indicate problems almost certainly at the front; check for damaged struts, worn ball joints, steering rack or incorrect tracking. On a car which has stood for a long time the top bearing of the front struts can partially seize resulting in notchy or poor self-centring steering; removal of the strut will probably be necessary in order to work lots of penetrating oil, or renew the top mounting/rubber doughnuts. Wallowing or bouncing on an uneven road surface suggests dead shock absorbers or a rusted out rear spring top mount - accompanied by loud clattering from the rear. Most, but not all front shock absorbers are replaceable, cars without removable hub carriers have sealed unit struts which have to be replaced whole. The rear suspension is quite simple and generally robust. A 104 ZS should have its rear anti-roll bar.
A smell of petrol following brisk left hand cornering probably indicates nothing worse than a leaky rubber washer on the filler cap! Firstly check all 5 tyres - condition and pressures, and examine the wheels. Dented or kinked rims (or odd wheels) hint at possible hidden and potentially expensive suspension damage elsewhere. New alloy 104 wheels are probably extinct, a car so fitted should have 5, not 4, and the spare tyre should be stowed in its cradle deflated. An electric tyre pump should be included in the tool kit of alloy wheeled cars.
Check that all the lights work and that the plastic lenses are not broken or cracked. Gently tug the headlight lenses, especially if they are full of condensation - they can drop off! Loose lenses can be removed, cleaned and re-stuck using high modulus silicone sealant from a builder's merchant. Resilvering brown reflectors is uneconomic. Peculiar antics performed by the indicator warning light and ticker are probably due to a corroded earth somewhere. Eventually the wipers will cease to self park and the indicators no longer self cancel, but all the switches and fittings are robust and keep working.
4): Looking after your 104. Keeping her together.
Remove mud and liberally apply Waxoyl (or similar) annually, at least, to the whole of the underside. Section 2 gives clues as to the most critical areas to treat, but some extra information is beneficial. The insides of the sills can be treated by removing the internal plastic trim (usually with speaker mountings) ahead of the front doors. This exposes an aperture in the steel shell through which rust inhibitor can be poured directly into the sills. The sills have drain holes along their length, unless these are temporarily bunged up first, all your wax will drain out before reaching the rear of the car - best to do the job with the car sitting nose up. Treat all the floor panels beneath the mats and seats and in the boot. Remove rubber bungs in the doors and liberally squirt wax, make sure you dose the window lifts and check the condition of the rubber weather seals. 5 door cars have an aperture in the boot (where the jack should live) giving good access to inside rear arches and rear wing bottom corners. Apply a good deal of wax to the void which houses the wiper motor- this will also help the wiper mechanism last longer. Ensure that all drain holes are clear.
5): Looking after your 104. Keeping her going.
Probably the most important aspect of caring for a Peugeot 104 is to regularly change the oil and filter, using a proper Peugeot filter. If you do choose a different brand it absolutely MUST have a non return valve in it to prevent the filter draining overnight thus starving the engine of oil at every cold start. A cheap filter will wreck your camshaft! Cheap oil is false economy, use decent stuff (I use synthetic) and various lubricant additives such as Slick-50 will greatly benefit your engine. Periodically ensure that the oil filler cap's gauze and hoses are free of gunge. Towing a 104 with the front wheels in contact with the ground is inadvisable since without the engine running the pressure lubricated gearbox and final drive will be starved of oil. Only use the plug spanner provided with the car, it lives in a spring clip at the back of the engine bay. Using a larger plug spanner may over-torque the plugs possibly stripping the thread in the alloy cylinder head - the plugs are deeply recessed into the head, so a stripped thread is a somewhat bigger disaster than normal. The pressed steel plug spanner (clipped to the back of the engine bay) eventually wears out and wont grip the plugs. Regularly check that the cooling system has enough coolant and no leaks or air-locks; use a decent anti-freeze. Once in a while check the cooling fan's function as described in section 3. Periodic flushing of the cooling system helps prevent overheating. A temperature gauge would be a very worthwhile accessory to fit. Don't let garages run the wheel-nuts on with an pneumatic spanner - especially when bolt-on hub caps are concerned. Water pump and alternator bearings will fail if the fanbelt is over tightened, allow about a half to 1 inch "play" in the belt. Fitting an in-line petrol filter can save the grief of rusty bits blocking the carburettor jets. A jerky accelerator pedal can be cured by fitting an extra long cable (Hillman Imp) thus eliminating sharp kinks.
Never rev the engine when cold, keep below 2,500rpm for the first 4 or 5 miles and, especially in winter, let the car warm up for a minute - nobody appreciates being forced to sprint seconds after being dragged from bed. Avoid "slipping the clutch" more than is necessary (replacement is costly) and don't be snatchy with the gearbox. You should be able to change gear with just your finger tips; heavy-fisted gear ramming will be expensive. These engines are a little prone to pinking, especially with today's reduced-lead petrol, don't drive with leaden feet, use the gears and keep the car in tune. Some cheap brands of petrol disagree with my 104, but I use ordinary unleaded petrol with Millers VSP additive (endorsed by the FBHVC). 104s may well be able to cope with unleaded fuel without modification or additives, but as yet I am not aware that anyone has undertaken to test this on a scientific basis. Likewise I have not encountered a cylinder head conversion to unleaded specification for the 104 – it may well be possible to convert very successfully, but my inclination is not to use my engine as a guinea pig. Unless your engine is seriously gunged up, I would be disinclined to use a flushing oil – better to do a couple of oil changes in quite quick succession. This is especially easy if you do a DIY oil change instead of taking your Peugeot 104 to the garage. Once warm the 104 will rev freely up to about 6,000 rpm, but sustained high speeds will cause wear. Don't forget that the 104 belongs to an era when cars cruised at 60mph rather than today's 80+ and even the youngest right hand drive 104 is 19 years old now - be nice to them!
6): Looking after your 104. Bits and pieces.
Over the next few years sourcing parts for cars of the 104's era will become much, much harder; the UK "classic" scene won't be interested, Peugeot dealerships (many of whom have little knowledge of the 104s very existence) now hold virtually no 104 parts, a few are still available, but be prepared to have to order everything and pay through the nose. Scrap yards are being strangled with environmental red tape and have an increasingly faster turn-over of stock. Very few 104 "pattern" parts exist in the UK. It will be wise to stash a few key items for future use. The best source of parts is from a specialist dealer of obsolete and older genuine Peugeot parts, for many items this will be your only economic route. Lots of bits can still be found in scrap yards, but their supply of banger 104s is dwindling fast, most yards do not hold slow moving stocks of older cars. Second-hand parts can be brilliant buys if you know what you're looking for and breakers are often very knowledgeable. Many will give a money-back guarantee on items should they not work or fit - very fair, but time consuming if you can't test the part in the yard first. Unless you really know the seller, buying second hand engines undriven, or even unheard, is very risky. The good news is that 104 is related to early 205, Citroen LN, LNA, Visa, Talbot Samba and Renault's lumpy 14, a huge number of their bits are interchangeable and if your French is good, France's scrap yards are full of them. A compatibility list would be laboriously long and to ensure detailed accuracy for every part/model would be beyond my limited knowledge. Don't forget that French scrap yard will yield lightly used right hand front seats (ideal for replacing damaged UK driver's seats) and headlights that will dip the wrong way for UK driving! If you really want to keep your 104 on the road you could always buy a spares car very cheaply. Get a copy of Haynes excellent workshop manual, or better still, a Peugeot factory workshop manual if you can find one. Look on the internet, there are one or two good 104 sites (and clubs) in Europe. Join a club; Club Peugeot UK is the relevant club for Britain, though 104s aren’t exactly plentiful amongst their ranks. France and other European countries have clubs more useful to the 104 owner – providing you can cope with other languages!
It is an odd fact but many people think that as a car gets older (and more in need of some love), that it will thrive on skimpy, miserly servicing, or even total neglect. They are wrong. Tales of depressingly unreliable and fragile 104s are sometimes told by disillusioned ex-owners, their problems, however, stem not from their car, but an uncaring owner. I don't suggest that 104s never wear out, just that they are not inherently frail. My 1983 104, at 320,000 miles, still has her original and unrebuilt engine, head gasket, camshaft, timing chain, gear-box, etc and runs sweetly and economically despite me being a lousy and reluctant mechanic! Providing you undertake basic but careful maintenance, a Peugeot 104 can provide you with reliable and practical (pre-computer and pre-catalytic converter) transport at a rock bottom (post-depreciation) budget level.