Technical Snippets

Before you either tear your hair out or your motor out etc. Try some of the often overlooked but simple Technical snippets that may just be the answer you are looking for.

If you have any similar problem solving snippets you think will be of help no matter how obvious they sound to you send them to me and I will add them to this list.


All advice given with the best intentions,  use any or all at your own discretion. The site owner nor any of its contributors will be held responsible if you use any of the info below and get hurt in anyway or your property damaged.

Ally Cleaning

  1. From a Guy who races sidecars, he cleans all his Ally parts in a dishwasher, reckons they clean up brilliant.

  2. If its a small part of ally, put it in an old or marked saucepan with a good scoop of washing powder, boil for an hour, cleans the ally and the pan to perfection. Also leaves a nice clean smell in the kitchen (so you might get away with it)


Spongy pedal or excessive pedal travel

  1. Fit a Jag master cylinder to a Fiesta servo they bolt straight on for a good pedal (only recommended for disc's all round).
  2. fit a residual valve 2psi for discs 10psi for drums one of each for combined but only if master cylinder is lower than calipers and usually only needed if an American m/c is fitted as most British are fitted with internal residual valve rubber..
  3. Silicone Brake fluid  Lockheeds version is :-  quote:
    Our technical department receive  an alarming number of calls from motorists reporting troubles with silicone brake fluid. AP Lockheed neither markets such fluids nor recommends their use with our own  or any other braking system.
    Virtually all the problems relate to long /spongy pedal sudden loss of brakes hanging on of brakes. they reflect certain properties of silicone fluid noticed by us over the years and recently ratified by SAE publications , namely :- high ambient viscosity high air absorption high compressibility low lubricity immiscibility with water
    IE: Long/spongy pedal:-

Brakes sticking on.

  1. Make sure the pedal travel has not been taken up to much on the master cylinder rod as no play on this rod will hold the brakes on once engine is running (with servo). 
  2. Have you got an electronic line lock? is it the right way round? is it faulty?

Improve your jag brakes.

  1. The chassis on my A Sedan has front suspension based on Jaguar uprights, fitted with the original, Dunlop calipers. These calipers first saw the light of day in the early ‘60’s and they are pretty inefficient. Worse still they cost an arm and a leg to recondition!

    The hunt for an alternative led me to the very helpful E-Type discussion group on Yahoo . I searched the archives and found the Volvo 240 reference. Seems it is a tried and tested alternative to third party brake upgrades.

    Get yourself a pair of 240 Vented Disc calipers from the scrappies, (or £120 a pair reconditioned), open up the mounting holes very slightly and bolt ‘em on! If you are running the original solid discs for the S1 E-type, make up 4 spacers so the E type disc runs in the centre of the caliper. If you replace the discs with the later S2 Vented discs, then no spacers are needed. You then need sort out the pipework. The Volvo runs a dual pipe system so you need to cater for this. Simplest method is to add a junction and simply run 2 pipes as the original Volvo. An alternative method is discussed here, on the Jaguar Drivers club site.

    So what I hope to end up with is a much more efficient, 4 pot braking on vented discs for a lot less than the cost of a refurbish on the Dunlop system.


  1. While trying to source a replacement brake booster (Servo) for a Dodge Coronet, one guy got a Volvo one from the breakers, simply because it looked big enough to stop his Dodge. A little bit of adapting, made the pedal and master cylinder fit and Voila the Dodge now stops better than it ever did with the original factory brake booster.


Setting the SU

  1. You need to make sure the float level is set correct, that there is  no play on the throttle spindles, the needles and jets are not worn and the air valves move freely inside the dashpots.  Assuming you have the correct or near needles and dash pot springs then the plug readings should be fairly uniform from 1 to 4.  Start by zeroing the jets by screwing the mixture nuts or screws until the jet is flush with the top of the holder, take the dash pots off to see! then back the adjusters down by about 1 1/2 turns and put it all back together. Then the throttles need to be balanced before you do anything else, if you can beg or borrow a balance meter set up the throttles at idle so both carbs flow the same amount of air. Also make sure the throttles open together after you've set the balance.  Then you can adjust the mixture. There should be a lifting pin on the side. If the mixture is correct at idle, pushing the pin up so that it lifts the dashpot by about 1/16" should make the engine note rise then drop back down to normal. If it continues to rise the mixture is too rich, if it drops or cuts out it's too weak. Use "Three In One" oil in the dash pot dampers.


  1. Yorkshire Street Rod chassis have the Rad mount 1 inch too high so that a standard A Rad wont fit.

  2. You can use a complete Mazda Pickup chassis for a 40's Willy's body. If you do, the chassis needs to be shortened about 10" to make it 103" long. There is a section just forward of the rear springs which is parallel, so you just cut here and shorten - angle cut, and plate over it. The Mazda steering can be used, but has to move back (lengthen the column). The engine has to go back about a foot, and you don't have to cut the bulkhead back either, unless you use a 'real' engine. If you use the Mazda lump when building, you should qualify for using the reg. (could change it later on) If you want the car high, just put it on as is, to lower it you can channel it or do the usual suspension mods. Naturally, the springs are too stiff, but it should handle like a racecar! A
    stiff and bumpy ride. You can use a Sherpa petrol tank behind the passenger compartment as the Mazda one usually crumbles once you try to remove it but remember you need a fire-wall for this to be legal!, also a good idea is to fit a cage and mount the doors off this, not just the body.


  1. Big Block Fords come in 370ci (truck only) 429ci and 460ci. FE big blocks come in 332ci, 352ci,390ci,406ci,427ci &428ci.   The 400m is not a small block or big block, its a one off oddball in the ford line up. The block is a tall block Cleveland (0.5'' higher) with a long stroke crank. The top end is 2V Cleveland. They are best built as a ''torquer''.

  2. Sealing problem cylinder heads "top secret" tip for sealing head gaskets is to paint them with Aluminium (silver) paint and fit them whilst still wet ! then Torque down quick. Never Fails to seal two flat surfaces, yet still comes apart when required, Des. 


  1. Exhaust System Crossover Pipe Installation. The best way to determine where to put the Crossover pipe is to take some spray paint and paint a section about 2-3 feet back from the collector. Start the motor and let it run for just a short time. While motor is running watch to see the point at which the paint doesn't burn off anymore. The paint will discolor further back, but the point at which the paint doesn't burn off is where you want to place your Crossover. Match the size of the Crossover to the size of your existing pipe.

Gear Box / Transmission 

  1. Work out your final drive or revs with your set up what size tyres would be best etc etc 

  2. Overdrive Gearbox Idea:Use an overdrive unit from the back of an old Jag know the thing that can be unbolted from the main box.......Triumph Stags and MGB's used them. Make a new front cover to keep the oil in and this unit can be anywhere between the box and diff.

  3. Refitting the Torque converter If you do not locate your torque converter fully home into the front pump your auto box will be knackered in a few miles one idea is, when refitting a torque converter into a box, have the box upright, fit the torque converter on to the shaft and give it a few spins in either direction, with a bit of luck it should drop in ok, if not try giving it a shake, and repeat, in most case u will find that the torque converter needs to be below the level of the bell housing, regards J.F You know your torque converter is full seated when you bolt up your engine and you can rattle the converter with its mounting bolts.

  4. Slipping Auto: Before you take out your trans for a rebuild cus it is slipping check that the kickdown linkage/cable is operational and correctly set. If it is not set to full open at full throttle this will cause slipping and will damage your trans if not sorted soon. The only exception I know of is the C4 & C6 these boxes can be run without a kickdown linkage as the kickdown does not vary pressure as in all other trans (if you have an update let me know).
  5. Rover gearbox ratios ratios for a Borg Warner 65 auto as follows
    1st   2.39:1
    2nd   1.45:1
    3rd    1.00:1
    Reverse   2.09:1
  6. C3 C4 C5 identification: To Identify the tranny , count the bolts holding the pan on :- C3 has 13 , C4 & C5 has 11.(C6 has 17 , just for the record).C4 & C5 are virtually identical apart from a few minor internal changes & the position of the dipstick.(C4 dipsticks are screwed into the side of the pan) C5`s came into production in 1981.
  7. C4 & C6 speedo drives are interchangeable.
  8. All Ford four bangers from 105E Anglia to the latest Zetec have the same bolt spacing to gearbox so a 5 speed Sierra box will fit a 105E or a Zetec engine will fit a 105E gearbox. The bellhousings all have the same pattern on the gearbox so you can interchange all gearboxes including V6 s. You need to watch out for the size of the bearing in the end of the crankshaft as this can vary
  9. Ford Clutches If you want to use a diaphragm clutch with hydraulics you will need a MK2 Cortina bellhousing complete with larger slave, master cylinder and bigger bore pipe. If you use the coil spring clutch hydraulic assy the clutch will be in or out with no feel and limited mileage.
  10. Early Sierra boxes can be difficult to get into gear and need special thinner oil to make them work. Fit it to all the boxes and you wont have any problems. 
  11. Stiff clutch pedal Now the theory is as follows. The master cylinder is always smaller than the slave cylinder as the slave cylinder has to travel less than the master (I think) to what degree is up to you. The smaller the master cylinder the nearer the floor the clutch will bite also the clutch will be less stiff, more stiff with a larger master although you get more travel before the clutch bites. On one application  the best combination of bite, feel and softness was with a 3/4 inch bore slave cylinder and a 5/8 master.
  12. Diff to Gearbox Angle The angle that the mainshaft (not the prop) comes out of the gearbox needs to be the same as the angle of the diff face, else you may run into problems and will probably bend something. The mainshaft is parallel to the crank so if say the engine sits at 2 degrees down then the axle must  sit at 2 degrees up (towards each other).

    The engine can sit higher/lower than the axle but the two angles of the bolting faces either end of the prop must be identical. The effect of having them higher or lower than each other will be a slight loss of power as the line of power transmission is less efficient when it goes through two bends than when it is straight. The higher the difference the higher the power loss and it will begin to eat universal joints faster.
  13. Crankshaft oil seal fitting If you're attempting to fit a rear Crankshaft Oil Seal on your RV8 the Haynes manual will tell you that you need a Rover service tool. Well take no notice just get yourself down to Asda and buy a can of Grapefruit Salad, cut off the top and hey presto! Fits perfectly. Just gotta make sure that there's no sharp edges where the lid comes off. Useful and healthy! ;-) Cheers, Dally 

Glassfibre repairs

  1. Joining two pieces of Glassfibre can be achieved by holding the pieces with hardboard screwed to both sides, dont forget to use candle wax on any ply you use so as to release the wood from the body properly. Grind out to around 18" of join that done you can go over with a lot of matting layers until up to the correct thickness then once cured follow step 2.

  2. On a straight line repair you can get tell tale marks of the join showing through, this depends largely on the quality of matting and resin and the viscosity of the resin used. Tip. You can grind back to the new repair fill the repair with wet resin, you can use an accelerating compound to speed up the process for less sag or dripping. After the new resin starts to go off put a tissue layer over the patch make sure it is not higher than the body repair, recoat with new resin and put another tissue coat over the repair, hey presto this should be fine and ready to fill. Another tip is that matting can be easily cut when it is in the green stage this is the stage when the resin is not sticky but dry and still soft. Good resins hardeners and matts and accelerators can be bought from specialist companies in exchange and Mart it is normally sold in lbs..........Paul forgot to mention the wax or other releasing  agent ... otherwise you'll have a lot of sanding.


  1. Changing Polarity  All you do is swap the battery terinals over and flash the dynamo, you will need to change the batter clamps as the pos and neg are different sizes. Take a wire from the; now positive terminal, and flash it on the large terminal of the dynamo, you must disconnect the two wires on the dynamo first. Do this 'flashing' a few times, re-connect the dynamo and all should be well. Don't forget to change the ignition coil terminals over as well. Geoff Kremer
  2. Misfire If you are experiencing misfiring after converting from pos to neg earth, make sure you have the coil fitted the right way round with neg to dizzy. Failure to do this will burn out points very quickly.
  3. Rover V8 SD1 engines running the original electronic dizzy. Symptoms: Intermittent mis-fire and poor starting. A common problem with these Lucas dizzy's is that the pick-up wire (three core ribbon cable) going to the pick up head inside the dizzy can fracture internally. To test this, disconnect the vacuum pipe running to the side of the dizzy. If this stops the problem then the wires are fractured.
  4. Dizzy wiring Rover V8 Because of the large current draw when cranking A Rover V8 uses "cold start" wiring. There is a spare terminal on the starter that supplies 12 V direct to the 9v coil to make sure it starts. When running normally the12v supply to the coil is cut down to 9 by a ballast resistor. Make sure all that is in place as, depending on what combination of parts are wrong it either will be a Mare to start or will burn out points and let you down.
  5. Rover V8 Spark Plugs While working on a mates car yesterday I remembered something that may be of help to owners of early P6 based v8s. These are no longer listed in spark plug catalogues so if you ask for Rover V8 plugs you'll normally get given ones suitable for an SD1 engine ( N9Y's or equivalent ? ) .Anyway the P6 started off using L87Y and later ( Jan72) changed to L92Y plugs to cure a persistent high speed misfire that was apparent under continued high speed running.I think the difference is that the L range is a snub nose plug unlike the projected nose of the N series.
    Having said all that I have only given the Champion plug numbers for reference as I stopped using Champions a long time ago( quickly followed by Bosch but that's another story ! ). Kev Rooney.


  1. Fitting An Efi in ya Rod Apart from all the injection bits and bobs on the engine you will need the ECU, fuel pump and its relay and the Injection loom. If you can get a circuit you can narrow the feeds down to; Battery feed, ignition feed, earth and ignition pulse ( if used). The battery feed can come directly off the battery. The ignition feed might come from a relay that is also fed from the battery but switched by the ignition, try and use this option if you can because it will reduce the load on the ignition switch. Use a really good earth point and the ignition pulse if used should be taken from the dizzy side of the coil. Some EFI setups also use a feed from the starter wire going to either the ECU or fuel relay to run the fuel pump during cranking.

Kustom Tricks

  1. Shaved Handles If you remove the standard handle you'll be left with a large hole thru which you can view the mechanism. You'll see the large bar that the outer push handle bears on. One of the favourite trick (To Dempsey) is to weld a nut to this and then install a chrome bumper bolt that you cut to length to be just level with the door skin. Plate over all other holes and weld a washer over the door skin which will tidy up the area around the chrome bolt. This type of handle can be modified so instead of the chrome bolt ,a larger piece of metal shaped to follow your door skin shape can be welded to the bolt attached to your lock mechanism. This means the handle will appear to be an integral part of the skin with only a small clearance around it for operation.

  2. Bear Claws: look at polo/golf door locks ,they are " bear claw" anti burst type latches that fit easily into the door aperture and can be easily modified to work as above.

  3. Pop Roof insert Recent talk on the uk hotrods e-mail group has come up with some interesting alternatives to the age old problem, which modern roof will fit a Pop. Well believe it or not so the group consensus is the good old Sierra. Yep the Sierra so you can have a tilt slide sunroof if ya want and even an electric one if you pick the right model. Also my mate Harry used the Nissan Cherry one that fits bang on aswell. Even heard the Golf will work aswell, though one guy says the Mk3 Cortina is an absolute perfect fit mind you not as plenty full now, so ya pays ya money and ya takes ya choice... Sounds like the Sierra is favourite.


  1. You cannot use straightforward clear Perspex for tail lights.  They have to be made out of 'diffuser' plastic, the sort of stuff used to go over neon striplights in shops and factories. In fact you can turn these up second hand in your local free ads, usually under 'building material' or 'lighting'.  Alternatively you can get the stuff in sheet form from your local plastic supplier, found in the Yellow Pages. It only cost me a tenner for a sheet of 8 x 4.  For colouring you need to go to your nearest plastic model hobby shop, shoulder your way past the anoraks, and ask for a couple of tins of Humbrol 'clear' paint.  Sounds strange I know, but it dries translucent, allowing light to pass through it. So you need red and yellow.

  2. Always wire any heavy users through relays much safer, I have found that when updating old cars to halogen the fitting of relays has always shown an improvement in brightness.

  3. Setting light height: To set up lights: set up the car on a flat and level surface, close to a wall and mark the centre of each light move it back as far as possible, say 10-20ft, and put the headlamps on main beam, set them so they hit the cross you've marked on the wall. Also if you are upgrading the wipac quadoptic are much better compared to basic halogen ones.

  4. Flasher dont work: flasher relay may be shot or your bulbs are the wrong wattage. You need 2 bulbs per side at 21 watt to make it work. If you are using side repeaters or similar these are only 5 or 7 watts. If you can't fit bigger bulbs into your light unit you can wire in extra correct wattage bulbs under your dash or similar. This is all presuming the indicators are earthed correctly. Remember if fitted to the body they need a separate earth lead to  chassis.

Metal Repair

  1. Can I suggest the very best of all metal epoxy adhesives.... DEVCON. Absolutely brilliant stuff. For steel you need 'Plastic Steel A putty' or 'Plastic steel B liquid'. I've used this stuff for years and it's never ever let me down regardless of the application. By4now Geoff.


  1. Plug readings should ONLY be taken directly after a  full throttle run and the fact that they read different at idle is misleading because any starting enrichment won't have been burnt off.

Power Steering

  1. A good pump to use is the ZF unit as fitted to Carlton, Astra, Cavalier, Range Rover etc, this is a very neat pump that is easy to mount and has a remote reservoir. Langy

Rear Axle

  1. All diffs use a crush washer to set clearances removing and refitting oil seals can be troublesome. Start with your torque wrench on a low setting and keep upping slightly until you can check the setting at which it comes undone. Add 5 lbs to this to retighten.

  2. How do I tell the  difference between an 8" and a 9" axle? The easiest way to identify a 9" Ford housing is when looking at it from the yoke side (front), the stud/nut at the 7 o'clock position is concealed by the pinion bearing casting. If you can get a socket and extension on this nut vs a wrench it's an eight inch. Chuck

  3. Axle Widths If you can hlep make this list complete please send me any info you have.
    105e Saloon 48"
    105e Van 50"
    Capri MK I 54"
    Capri MK II 56"
    Escort MK I ??
    Escort MK II 54"
    240 55.5"
    760 69.5"

Removing stickers or glue residue

  1. Autoglym tar remover .... works a treat on most glues ... doesn't harm paint either !

  2. use boiling water straight from the kettle, it softens the plastic and the glue at the same time and they become easily removable even stubborn hardened plastic stickers come loose after a few applications of the ole hot water...................Paul

  3. Useful way is remove leftover sticker glue etc on windows is to spray a small amount of WD40 on the glue and wipe it off with a bit of rag.  Jamie


  1. PTFE bushes the best grease to use is KEENOL made by Duckams, apparently it's water and salt resistant. It stops them squeaking and fretting.

Starting Problems

  1. Petrol : if its been sat about a while the " light ends" of the fuel , the stuff that makes it ignite evaporate. Don't drain it out, fire it on a fresh mix put straight in the carb and add the remains to the tank, it'll normally run OK. Tech info courtesy of Meester P and his Dad ( ex Esso refinery ).

  2. Slow Starter Rover V8:  I spent months chasing a fault on my starter motor on my rover, usual thing stripped it, cleaned it, painted it assembled it 2 years later put it on the car to fire up and slow as hell took about 2 months before, I tried reversing the wires on the solenoid, the one that comes up from the actual starter motor on to the solenoid, put it on the other terminal and the main live to the other one different starter all together. JF

  3. Slow starter Rover V8 my starter problems turned out although the battery read fully charged it was loosing too much power cranking  should show about 12.96 volts static and not drop below 11 cranking. I was loosing huge amounts of current through "open weave" earth strap. I fitted 2 insulated big bore ones and it spins like a good un.


  1. To reseal your windows go to autowindscreens and ask for a tube of arbomast its linseed oil based and always stays moist and never sets don't be tempted to use silicon it knackers the rubbers up and also when the seal breaks it breaks for good .

  2. Never lay a windscreen down flat as in time it will bend and wont fit the hole you originally took it out off.

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