The following technical tips have all been written by Tiger (or Alpine) owners and many have been produced in previous issues of Cats Whiskers. STOC cannot guarantee that following the advice in these tips will be entirely hassle or risk-free. So there can be no recourse to STOC but if anyone finds an error or omissions please let us know. If you have a tip drop a line to STOC – see Cats Whiskers Tech Tip index below.
Tips have been split into two categories – In Depth and Quick Tips. On the whole, In Depth tips are one day’s work or longer and the Quick Tips are exactly that – quick and fairly easy.
In Depth Tips
Paul Norton, Cat’s Whiskers Issue 43 (1992)
There seem to be two areas which give the practical classic car owner the willies: electrics are the most obvious; and running a close second are brake servos. I think the problem in both cases is that you can’t actually see what is going on! So here is a quick visit to brake servos.
A bit of background
Up to chassis number B382001284 Tigers had the small chamber (approx. 5 1/2″ diameter) MkIIA servo which had a 2:1 boost ratio. This was replaced from B382001285 by the large chamber (7″ diameter) MkIIA with a 23/4:1 boost ratio. The MkIIA servos are the ones with the end plate held on by either seven or eight small bolts and with the vacuum pipe connected to a union on top of the cast aluminium body. The later MkIIB was introduced after Tigers had finished production so was never original equipment (although Girling did recommend it as a replacement for worn out MkIIA’s). The MkIIB has a clamp band around the vacuum chamber and the vacuum pipe connected directly to the vacuum chamber. There are also some internal differences.
No or weak servo action (in other words, a heavy pedal)
Usually caused by someone fitting a length of heater hose instead of the proper vacuum hose: this is more prone to internal collapse which stops the engine sucking the air out of the servo.
Other possible causes are loose connections at either end of the vacuum pipe; a blocked air inlet (under the filter) or a clogged filter itself. Also possible (but not that likely) is a serious internal fault such as failure of the output piston, jamming of the control piston or air valves or seizure of the air piston.
Brakes “hanging on”
Usually only happens after the unit has been reconditioned and Girling say this is usually due to misalignment of th vacuum piston. If you examine the unit carefully you will se that the piston rod and vacuum chamber are both quite accurately located by the plastic spacer and guide bush. As this is the last part to be fitted into the main bore, any misalignment should only be due to the vacuum chamber being distorted.
It is much more likely that the air piston is sticking due to a swollen or excessively firm foam backing ring behind the leather piston seat, or the use of non-Lucas-Girling kits which don’t contain any leather lubricant. There have been considerable variations in the resilience of the foam rings both in non-Girling and genuine kits. Hanging on can also be caused by misalignment of the air valves, but provided these are free they should self-align quite happily.
Brake pedal going to the floor gradually (or indeed quickly!)
This obviously means a leak somewhere, but the question is usually Where?
Callipers hardly ever leak, and when they do it’s pretty obvious. The same goes for the flexible hoses (don’t forget the one over the back axle) but stone damage is always a possibility. The solid brake pipes connected to the inner ends of the front flexibles are prone to rock damage and can easily fracture. Copper brake pipes are prone to vibration fatigue unless extra supports are added, so they could crack and leak on any long run.
The rear slave cylinders are the usual location for leaks and probably the first place to check but the master cylinder is also a source of leaks and it’s worth checking for brake fluid behind the carpet in the driver’s footwell. The master cylinder is also to blame if your foot is creaping to the floor but the fluid level is not dropping. In this case it’s the small seal that closes the return feed to the reservoir which is to blame.
If the fluid level is going down and you’re absolutely sure there are no leaks anywhere then it looks at last as though your servo is leaking internally. After topping up the master cylinder for several days you will eventually lay a smoke screen James Bond would have been proud of as the fluid reaches a level in the vacuum chamber high enough for some to be sucked into the inlet manifold and burnt. It’s quite spectacular! The smoke is quite characteristic – dense white which can’t be mistaken for oil smoke. If you remove the servo and shake it you’ll hear all the fluid sloshing about inside the vacuum chamber.
What to do with a duff servo?
Bypassing it is legal but will fail the MOT. If a servo is fitted it must be working – I don’t know anyone who’d want to drive a Tiger with no servo anyway!
Replacing it with a new unit is not possible as Lucas-Girling no longer manufacture in-line hydraulic servos. You could try to squeeze a Lockheed unit in but I don’t know if there’s enough room to do that.
Picking up a unit from a scrap yard or auto-jumble is fraught with danger as it could be no better (or even worse) than your old unit. Picking up a newer MkIIB won’t be much better as these are mostly quite old too, and if they have internal leaks they cost a lot more to recondition. They don’t, however, suffer from the dreaded “hanging-on”.
Reconditioning your own servo with a kit is a fun way to spend a day – be warned that you need a moderately long-nosed pair of fine internal circlip pliers and a foot of 1/8″ steel wire to bend into a special tool. Genuine Lucas-Girling kits can be hard to find – alternative kits usually have no instructions and no leather grease. I have also found cases where genuine kits have contained the wrong parts – parts which appear to fit but leave you with internal leaks!
So after all this negativity, your best bet is to find a nice chap who offers re-conditioned servos.
I recently lubricated the bearings in my Tiger’s steering column and am I glad I did. They were dry! I followed the recommendations in the Shop Notes manual and have some further information.
My bearing carriers were well and truly stuck in the column tube. I am sure that I could have wrecked them if I had tried to pry them out. I disassembled them by first taking the column apart as far as I could, leaving only the bare column and shaft. I then removed the circlips from both ends (MkI) and rapped the lower end of the column shaft on a hardwood block. This forced the top bearing carrier out of the column. I then reversed the column and rapped again to remove the lower carrier. The carrier is easily able to take this reverse pressure. The shaped washer seems to have no purpose other than to prevent damage when the bearing is removed in this fashion.
In rebuilding the lower bearing, I packed the carrier half full of grease. If dirt sticks to the grease, let it stick to the top layer, far away from the balls.
To further shield the lower bearing I fitted a leather ring as shown below.
I punched a 1 1/16″ hole in a 1/16″ thick piece of leather, about 3″ in diameter. Once the column was reassembled, I stretched the shield over the bottom spring and pushed it tight against the column with a screwdriver, then trimmed it to the same diameter as the column. This extra seal should keep dirt and water away very effectively.
Be Warned not Warmed!
Lucas, in their wisdom, really did a number when they designed the Tiger’s electrical system. At least it’s easy to change the fuses – there are only two! Most modern automobile manufacturers employ fuses combined with a variety of relays, resistor links etc. to protect the car’s wiring. How did Sunbeam provide protection for the electrical system using only two? They didn’t!
The purpose of any fuse is to provide a weak link in an electrical circuit which burns open before the wiring does in case of an overload or short. The size of the fuse is expressed by the amperage rating and indicates the maximum current which can be carried before it opens. If the rated value is exceeded, the fuse link opens, stopping the current flow. High-current rated fuses may not protect circuits with small diameter wires since the wires may burn before the fuse can blow. Conversely, a low-current rated fuse in a large diameter wire circuit may blow even though the circuit was never in danger. Unprotected circuits have no fuses and thus will burn at the weakest point if the current load exceeds the capacity.
Your Tiger, like MGs and other mid-60s British jewels, has a potentially serious problem in these unprotected circuits. Which ones? Most! A glance at the wiring diagram in the Shop Manual shows that the following circuits are unprotected:
- Parking lights
- Tail lights
- Fuel pump
- Dash lights
- License plate lights
The only fuses in the entire electrical system consist of one wired directly to the battery (to protect the horns and map light) and another wired through the ignition switch (to protect the directional lights, back-up light, instruments, windscreen wiper and heater blower motor).
Before discussing the circuits to protect, a few words about fusing are in order. The standard automotive fuse is of the metal ribbon type. The current rating of the fuse is established by the diameter or thickness of the metal ribbon. The large 35-amphere fuse has a pretty big ribbon, whereas the one- or two-amp fuses have a fine wire. Although this type of fuse is widely used and adequate for most applications, there are two disadvantages which may limit its use. Mechanical damage can cause the fuse to fail prematurely due to vibration (for this reason, critical circuits are protected instead with fusible-link wire). Fusible link wire looks like conventional rubber-coated auto wire, but is made of special wires which burn out if the rated current is exceeded. The wire is resistant to mechanical damage and can be spliced and soldered in the usual way. It is available in several wire gauge sizes and is found in most auto electric shops.
The second disadvantage of the conventional metal ribbon fuse is that it opens immediately, and in circuits which draw high peak current (e.g. cooling fans) may blow in normal use. This problem is solved by using a special type of slow-blow ribbon fuse.
There are lots of ways to correct the deficiencies in the Tiger’s electrical system. My approach requires minimal effort, consisting of adding a Lucas fuse block, nine in-line standard ribbon fuse holders, and three fusible link wires. Slow-blow fuses can be substituted in other circuits as you see fit.
In my attack on the Tiger’s wiring deficiencies I decided to place in-line fuse holders on each exterior light (except directional and brake which are already fused). Fuse holders are available from most auto parts stores, but beware of holders used on car radios as the plastic may not withstand the heat in the engine compartment.
With the help of the Tiger wiring diagram it should be easy to locate the appropriate wires. The wiring for the headlights and front side lights runs along the hood under the inner fender. I placed three in-line fuse holders on each side, staggered to keep the bundle smaller. Attach snap-in plug type connectors to each holder and remove the wires from the existing snap connectors and insert the holder. You will need an extra female to complete the fusing. Check each circuit as it is reconnected.
The tail lights on the rear feeder can be fused in much the same way, using the connector at the left side of the dash. Fusing for the fuel level sender can be omitted. The fuel pump needs fusing in a different manner (see below). The indicators and brake lights are already fused.
The final step is the addition of another Lucas fuse block (available from most Tiger parts dealers). The extra block allows you to separate the circuits so a short in, say, the temperature gauge doesn’t wipe out the tachometer. You might also consider buying two and replacing the existing block, which may be corroded after years of service.
In the stock set-up, the fuse with the brown (in) and purple (out) wires is powered directly from the battery and is hot all of the time. The other fuse (green and white) is powered from the ignition switch. Locate the new, extra fuse box beside the existing box and re-arrange the load so that one becomes battery-powered and the other switched. From the input sides (brown and white) make a short jumper cable to supply power to the other set, thus making more circuitry independently fused.
Thus far, we have doubled the number of fuses in the main circuits and installed individual fuses on each exterior light circuit. For additional protection in the headlight / tail light circuit I installed a fusible link in the main power feed into the dash mounted light switch, using the appropriate spade connectors. The size of the fusible link wire must be the same as the wire size of the circuit in order to provide proper protection. In addition to protecting the entire exterior light circuit, this fuse link also protects the instrument lights. (You can’t use a conventional glass/metal ribbon fuse here because of the mechanical damage problem outlined above).
Also install a fusible link wire to protect the ignition feed wire, which runs from the ignition switch through the tachometer and ballast resistor to the coil. Terminal fittings may need juggling to keep the installation neat. As the stock electric fuel pump has no fuse protection, install a fusible link in the harness at the rear feeder connection at the left side of the dash in the white wire.
With all these extra fuses, labelling each one is a good idea! And make sure each circuit is tested as it is installed.
Rear Spring Mount Reinforcement – by A J Vilt
A weak point in the Tiger’s super-structure is the front mount for the rear spring. In restoring my Tiger I found that both sides needed attention. While I was at it, I designed a metal patch that not only strengthens the spring mount but also reinforces the frame at this critical point.
The patch can be cut from any piece of suitable sheet metal. I used a rather heavy 12 or 14 gauge. The only critical dimensions are the size and position of the mounting hole, which must be determined after the patch is cut and fitted to the frame. The patch should look like the following diagram:
The pattern for the patch will work for either side of the car – just make the bends in the opposite way so the two plates are mirror images of each other. The patch somewhat resembles a horse, with three bends along the dashed lines. The 90-degree bend roughly corresponds to his stomach and allows the patch to be attached to the two sides of the X-frame. Shape the bend at the “neck” to fit the angled X-member and the straight rear frame member. Bend the “nose” 90 degrees to allow the rear portion of the pattern to fit the front portion of the rear sub-frame. In bending, watch the alignment of the mounting bolthole. Once you have actually cut out the patches, it is fairly obvious how they fit.
Patches should be installed on the inside of the frame where the X-member begins to straighten out. Be sure to check the other welds and repair any cracks before applying the patches. Remove the spring from the front mount so the heat doesn’t damage the rubber bushing, then insert a spare bolt through the patch to keep everything in alignment. Also, test fit the plate and spring to be sure it all fits in place easily and that the spring bolt will engage fully. Shape the patch to a tight fit against the frame member using a ball-peen hammer, then weld. One way to be sure to keep weld splatter out of the threads in the mount is to insert a carbon rod (such as the kind found in the centre of a D-size flashlight battery) into the hole before welding starts. Be sure to clean the rod thoroughly before use.
To add more strength to the patch, make the holes slightly larger than needed, then weld a bead around the hole as well as along the frame members.
Fitting a 289 Engine into a 260 Tiger by Brian Postle
Quite a few Tiger owners are converting their cars to the larger 289 or 302 engines. I will try and point out a few of the pitfalls and try and save you some time and money.
All 260 engines have what is described as a 5-bolt bell housing. The easiest way to fit a 289 is to try and find an early 289 which will be of 5-bolt design and therefore fit straight in with no problems. These 289 engines are, however, usually hard to find because they were made in relatively small numbers (as during 1965 Ford brought out the 6-bolt 289.
If you have a 6-bolt 289 or 302 what you also need is a 6-bolt bell housing. Most people use the flywheel off their 260 which uses a 10 1/2″ clutch. Therefore you need a bell housing which was designed for that size clutch. If you get one with an 11″ clutch, the starter motor will not mesh with the ring gear or flywheel.
The following part numbers are of aluminium 6-bolt bell housings which you can use with the 10 1/2″ clutch:
- C5DA – 6394 – A
- D20A – 6394 – AA
- D5DA – 6394 – AB (swap clutch arm pivot from old 5-bolt bell housing)
I know these fit as I have used them, and there are more available (compared to a 5-bolt 289 engine).
The next problem encountered is the size of the hole in the bell housing, where the gearbox front retainer fits. All Tigers (except MkIIs) have a 4-11/16″ O/D retainer – the bell housing is 4-7/8″. The best fix is to buy the larger retainer; alternatively get a ring machined to fit between the retainer and the bell housing. It is now a simple matter of drilling the bell housing to suit the bolt pattern of the gearbox (a MkII gearbox will bolt straight on).
The final detail is to buy a clutch slave cylinder bracket for a 6-bolt bell housing. This looks just like a 5-bolt but will fit the 6-bolt.
On the engine size I find it best to use the aluminium timing cover and water pump off the 260 engine.
Running Hot? How to put more air through your radiator by Brian Postle. Make up a plate approximately 27″ by 6″. This will fit between the bottom of the radiator panel and where the number plate mounting nuts are. Hold in place by spot-welding, pot rivetting or use self tappers (whatever suits you).
The plate ensures that any air entering just above the bumper goes through the radiator, not out of the bottom of the valence. It can be fitted with the engine in situ, but I recommend making up a cardboard template first.
Convert your engine to a spin on-off oil filter. By Brian Postle
Are the hoses on your oil filter set-up cracking and leaking? Do you want to tidy up things around the engine?
You can convert your engine to a spin on-off oil filter by using the Ford Nipple in the block, Part Number DIAZ – 6890 – A and the Fram Filter PH2874.
This is a very neat installation and allows you to now mount your coil where the old oil filter was. Note that, with this being a smaller filter you should change your oil more regularly.
Missing / damaged radiators. By Brian Postle
The drawing below may be of some help in getting radiators repaired. Serck & Marston radiators can easily fit uprated cores to your Tiger radiator.
For missing or very badly damaged radiator-owners, new end tanks and brackets are usually available from the California Association of Tiger Owners (C.A.T.) in America.
Rust Removal Solution, supplied by Walt Jobson, Australia
Mix two parts molasses to one part water in a plastic container. Suspend parts in the solution for one or two days (depending on the amount of rust) then hose off. DO NOT USE with aluminium. Also note that the mixture will not work on greasy parts.
Once bolts, nuts and other non-precision items are free of all rust, heat them over a charcoal fire then toss them into a pan of motor-oil to produce a baked-on protective finish (the part takes on a dark, rust-resistant finish). Watch out for flames and fumes from the oil though.
When this tip was published in Cats Whiskers Issue 47, a free Tiger T-shirt was offered as a memento to the first member trying this with a complete car. As far as we know, the offer still stands!