THE TRIUMPH 2000 / 2500 / 2·5 REGISTER
For owners and enthusiasts of the Triumph 2000 series of six-cylinder saloon and estate cars
It is with sadness that Clarion events have decided to postpone the Practical Classics Classic Car & Restoration Show due to the latest Government advice regarding the COVID-19 virus.
All tickets will be automatically transferred to the new date.
Update as of 27th May: new dates have been confirmed as 26th – 28th March 2021
Please go to www.necrestorationshow.com for more details.
Maggie Roberts, our membership secretary, is moving house on Friday 13th March. The new address details are :–
The Bungalow,
Ladyfield Road,
Kiveton Park Station,
SHEFFIELD,
South Yorkshire,
S26 6NR.
The telephone number for membership enquiries will remain the same; please see SIXappeal for details.
There may be some delays in processing memberships due to this, so thank you for your patience.
Unfortunately, we are having difficulties with the forum and at the moment Mike Stevens, our Forum Admin, can’t log on as an Administrator. This means he can’t action any of the administration actions (such as authorising new members or sorting out logging in issues)
This is being investigated and hopefully will be resolved soon. We apologise for any inconvenience and thank you all for your patience.
This year’s MG & Triumph Spares Day was memorable in more ways than one. Not only was Storm Ciara doing her best to bring the country to a standstill, (and nearly bring the roof down with the mid-afternoon hailstorm) but the Register stand was buzzing all day long. Congratulations go to Matt Field (and polisher Sue) for picking up ‘Best Triumph’ at the show and also to Maggie for handling the steady stream of membership transactions with no let-up. In fact she had 21 renewals, 2 rejoins & 2 new family members sign up during the show. Besides Matts lovely MK1, the Register stand also featured the Bradbury’s super MK2 estate – both drawing admiring glances. A lovely show enjoyed by all, despite the weather.
The Triumph 2000/2500/2.5 Register will be on stand 4-660 at the Restoration Show from Friday 27th – Sunday 29th March 2020. We will be recommissioning a Mk1 on our stand
Don’t forget to use the exclusive discount code for club members, published in Six Appeal.
David Manners Group are now pleased to offer Register members a discount off various part lines purchased through their Abingdon MG operation. It may seem an odd trading name for a supplier of Triumph parts but Manners assure us they have a good selection of items applicable to our vehicles.
One bonus is that you will be dealing with Register member and PI MK2 owner SIMON CARR – whos tale of tinworm can be found in the last edition of SIXappeal (Dec ‘19, page 22). Speak to Simon on 0121 543 1615 with your membership number to hand – and see what deal he can do for you.
To get the new website off to a flying start we’ve just had a short run of these 9cm square, self adhesive vinyl stickers produced. Emblazoned with the new ‘favicon’ (new one on me too…) logo as designed by our website creator Paul Girling, they are a fun new take on the Register name – pop one on your ride and show your allegiance! Available FREE to the first 40 members who send an SAE to the SIXappeal editor (address inside the front cover of the mag). Pop your membership number on the top left corner of the envelope. If you have a couple of cars then ask for 2. (Max 2 per household!)
Classic parts supplier Rimmer Bros have just launched their December sale of Big Triumph items – from rocker covers to rear lamps. See their website https://rimmerbros.com (Click on the rotating banner for 2000/2500 offers)
I would regard cleanliness of the components as the most important aspect of an engine rebuild, in particular the block and its oil galleries. Any residual machining particles or dirt in the oil galleries can get pumped straight into the bearing journals of the mains, big ends, camshaft and rocker shaft. Damage can be costly in terms of either premature wear or even total bearing failure resulting in another rebuild.
Dirt in the crankcase should not find its way into the oil galleries, as no particles below 15 – 20 (metric) microns (i.e. 0.0005906 – 0.000787 inches) should pass through an industry standard oil filter, unless the filter is so clogged that its by-pass valve opens. I have seen an instance where the inner O-ring was not fitted to a spin-on oil filter conversion, resulting in rapid wear to the bearings on a rebuilt engine, as the oil by-passed the filter picking up more and more debris, as more and more wear took place! Apart from this, dirt in the crankcase small enough to pass through the strainer of the oil pump will wear the lobes of the pump rotors.
Another less obvious place that crankshaft dirt particles end up is embedded in the seat of the oil pressure relief valve in the block itself, preventing the valve plunger from seating properly. The valve itself can stick open even further off seat. Soft, substandard reproduction valves are especially prone to this as particles embed into the soft metal more easily. The Original, and properly remanufactured, valve plungers have a hardness of around 40 Rockwell B. A stuck open valve can result in a sudden large loss of oil pressure, whereas particles on the seat in the block cause consistent low idle pressure, particularly when the engine is hot. A good rebuilt engine should idle at between 25 and 30 psi when hot. If less, and the rest of the engine is in good condition, it is worth cleaning the oil pressure relief valve seat in the block.
I had this tool made to clean the seat. It is made from a 9/16 inch drill bit shortened and reground to 118°, the angle of the pressure relief valve seat in the block. The cutting edge angle was reduced, so that this works more like a scraper than cutter. The tool is turned by hand using the wrench shown. It is surprising what granular debris comes off the seat in some blocks. The more dirt that comes off, the larger the increase in oil pressure.
It is not only the block itself that will harbour dirt. The following components should also be cleaned thoroughly:
Rocker cover (including internal gauze in later versions)
Rocker shaft assembly
Cylinder head
Engine front plate
Timing cover
Bridge piece across n01 main bearing cap
Timing sprockets
Sump
Rear oil seal housing
Crankshaft
Connecting rods
Main bearing caps and bolts
Pistons
Camshaft
Pushrods
Cam followers
Distributor/drive gear and pedestal
Petrol pump (where used)
Oil pump
Oil filter adaptor or housing
Cleaning the Crankcase
Some engine reconditioners offer a service where the whole block is immersed in powerful cleaning agent. H T Howards of Slough use a “decarbon fluid” which removes all external traces of oil, gunge and even paint from the block. This saves a lot of physical scraping, scrubbing and brushing, especially if the block is covered in thick, sticky, black gunge.
After degreasing, I mount the block on an engine stand, and remove any surface rust with a rotary wire brush, so that the block is ready for painting later. The core plugs are also removed at this stage. I prefer to use an oxyacetylene cutting torch to remove the plugs, simply heating around the edges to red heat and blowing a hole in the middle of the plug. When cooled, they will have lost their interference fit. A screwdriver is inserted into the hole, then the plugs can simply be levered out. I prefer this to any hammer and chisel method, as there is no risk of scoring their housings.
Oil pressure relief valve, spring and nut in special blue anodised alloy. Steel nut weighed 110g (Alloy 40g)
However, despite the block being clean externally, it is never to be assumed that the internal oil galleries will be clean enough for use. The main oil gallery that runs the full length of the block should be thoroughly cleaned. The distributor/oil pump drive bush should be drifted out using a 1/2 inch shouldered drift such as a 1/2 inch socket cap bolt. This is drifted up out from its underside.
Left – late Mkl & all Mkll Right – early Mk I
The 1/4 inch BSP plug (O/E no 118632) is removed from the rear of the block using a suitable Allen key. The plug at the front of the block is a bit more tricky to remove. I drill a 1/8 inch hole through the middle of the plug. I then use an oxyacetylene torch with its intense localised heat on the aluminium plug until it just starts to melt. The plug tries to expand but has to expand inwards as the block prevents expansion outwards. When it cools it contracts leaving a loose fit in the block. I then lubricate the thread with penetrating oil, drive a flat bladed screwdriver into the soft plug and simply undo it.
The six 1/8 inch BSP plugs (O/E no 118686) can be removed from the side of the block using a 3/16 AF Allen key. If struck a sharp blow with a hammer and punch, they will normally break their hold. If this fails heat up as with the front plug.
With all the plugs removed, a rifle brush and extension can be passed through the main gallery. Wash the brush in degreaser after each pass. Rifle brushes can be purchased from a gun shop. I made my own extension out of a piece of 5/16 inch old and 24 inch long rod. I use a combination of appropriate drill bits – turned by hand – and thread taps: 1/8 and 1/4 inch BSP to clean out the cross drillings to the cam and main bearings. A 5/16 inch UNF tap is useful to clean out the many other threads of this size on the block.
Next, the block is given a thorough flush as follows:
The oil pump bush is drifted back in with a shouldered bush. Don’t drive the bush too hard as the flange nears the block as the flange can be broken off. The old pump is refitted and the block placed in a domestic water tank (cost less than £10 from a DIY superstore). The block is supported on some wooden blocks so that the strainer of the pump is just above the bottom of the tank. The oil filter and the pressure relief valve and spring are also refitted.
Twenty-five litres of new degreaser (available from any good motor factors) are emptied into the tank.
A shaft will be needed to engage the tongue and groove drive of the oil pump. A PI distributor/metering unit shaft with the gears removed is ideal. If not available make a shaft out of a 6 inch length of 1/2 inch old bar with a groove cut out to engage in the tongue of the pump. The pump turns anticlockwise when viewed from above, so a reversible electric drill with a 1/2 inch chuck will be required. I usually run the drill for about 10 minutes, swapping gallery plugs around to divert and intensify flow of degreaser through the galleries.
Remove the oil filter and pressure relief valve. The engine can be removed from the tank and put on a table, or ideally, on an engine stand to wash with hot water. Dry with a blowlamp and paint with engine lacquer. I usually put a magnet in the bottom of the tank to see how much ferrous matter has been washed out of the block. The degreaser can then be salvaged for more basic tasks. When the paint is dry the gallery plugs can be refitted to the block.
I always use a drop of Loctite pipe sealer (available from engineering or bearing suppliers) on their threads. Refitting the plug to the front of the block isn’t so straightforward. The intended stick of thread (PS1103) tends to wind far further into the block than the original, which is not reassuring. I use the 1/2 inch alloy rod that comes with a Kenlowe fan kit and run about 3/8 inch of 1/2 inch UNF thread onto the end of the rod with a circular split die and die stock. By this method the thread is more tapered. It can be wound into the block after being covered with pipe sealant, cut off flush and filed flat.
If the engine has had the bores honed, or has been rebored, and new piston rings fitted always run the engine in on special running in oil. This helps the piston rings to wear/bed to their bores preventing glazing and thus premature oil consumption problems. Normal oils contain anti-friction additives which are detrimental to running in. I use Comma R05L. When the engine is installed in the car and filled with oil the reversible drill and pump drive can be used to prime the galleries, pumping oil into all the bearings and the rocker shaft before the engine has even turned.
When the assembled engine is first run with new piston rings on honed bores, a lot of ring swarf will be deposited when the peaks of honing marks wear into plateaux as the rings and bores bed in. At this stage a magnetic sump plug is highly beneficial which will pick up a lot of grey metallic paste, especially for the first 1000 miles after which the running-in oil should be changed.
Mobil 1 5w/50 synthetic oil is great for our engines, but has been superseded by thinner 10w/40 which I first tried on a high mileage 2000 engine. Oil consumption became unacceptable! My (since rebuilt) 2000 is now on Comma (who own Mobil) synthetic 5w/40, which I am evaluating. Oil consumption is no longer a problem. Modern engines use thinner synthetic oils because they create less drag, improving power output and fuel economy. If f were going to use a 2.5 engine to do a lot of heavy towing in a hot climate I would use Castrol RS10w/60. 2.5 engines run a higher crank bearing load with their longer stroke than the shorter stroke 2000. One can, of course, use cheap old 20w/50 non-synthetic oils which are relatively high in tars and waxes creating drag and thus need replacing more frequently than modern synthetic oils. Semisynthetic oils offer a good compromise.
I don’t regard any of the oils I know of as being totally ideal. There are many compromises involved. I would ideally prefer to try 5w/45 on my 2000, which, as far as I know. doesn’t exist. However. the oil pressure does not drop below 20 psi when hot on 5w/40. The greater flow rate of a thinner oil will help cool the bearings more than a thicker oil, but a thinner oil has a lower film strength. The lobes of a high lift cam would be my greatest concern, if the oil were too thin.
It will be interesting to hear what oil other club members are trying.
These are less necessary with modern synthetic oils which are designed to cope with lubricating a hot turbo charger. A temperature gauge can be used to evaluate the situation. Cleanliness of oil cooler. hose and thermostat is essential as any dirt will be pumped straight into the oil galleries and bearings. In most cases the oil is filtered before it passes through the cooler.
Very much at the heart of the matter, I wrote about this in my first Technical Article seventeen and a half years ago. (See first Register Service Notes page 1.151.) The key point for attention is rotor end float. Getting down to one thou of end float was a bit optimistic. 0.001 – 0.0025 inches is more realistic. If you have a new pump with more end float than this (0.004 -0.006 inches isn’t uncommon) then it will be beneficial to have the body machined or simply use a blue printed pump to start with.
Having stripped, cleaned and prepared the engine for decoke and reground the valves as described in the last month’s article, the engine has to be rebuilt and tuned.
The refitting of the valves into the cylinder head is the reverse of the procedure for removal, using the spring compressor in the same way. Remember to fit the close coils of the spring towards the cylinder head. The valve springs should be checked before replacing. The easiest way of checking a valve spring is by comparison with a new one. Do not be misled by the difference in free length of the spring as this does not always have any bearing on their load at the fitted length. The best way of testing springs is to place a new and an old spring into a vice, end to end, with a flat piece of metal between them. Determine the fitted length of the spring by placing a valve into the cylinder head complete with cotters and caps, but less the spring. Measure the distance between the two faces on which the spring rests. This distance will be the fitted length. Tighten up the vice with the two springs in opposition until the new spring is compressed to the fitted length. If the old spring is then shorter than the new spring this indicates \weakness.
Remove the carbon deposit from the crown (or top) of the piston leaving a ring around the outer edge of about 1/2″. A certain amount of carbon will have formed round the edge of the piston inside the bore. By removing the carbon to the edge of the crown, this ring would be broken which could cause heavy oil consumption. When removing from the top of the piston take care not to damage the piston with a sharp instrument such as a screwdriver. Stuff some clean rag into the openings on the nearside of the engine to prevent the particles of carbon from getting onto the cam followers. The hard carbon will cause uneven wear on the cam followers, which in turn will cause noisy tappets.
Refit any studs which may have come off with the cylinder head nuts and check those in the head for tightness. (I find it much easier to clean the top of the block with the studs removed. Uncle Stan Part) Clean all the flat faces of the cylinder head and the top of the cylinder block in readiness for re-assembling and remove the rag from the cam follower chest. Place the cylinder head gasket on to the top of the cylinder block. The gasket should first be coated with nonhindering gasket cement or grease. (I always use grease. Gasket cement can ‘blow’. – USP) Always fit the gasket with the seams uppermost.
Replace the cylinder head, nuts and washers remembering to use the high tensile nuts and tighten down. Cylinder head nuts should always be tightened evenly, starting from the centre and working outwards towards the ends. If a torque wrench is available tighten the nuts down to the correct torque. (The Mark 1 engine is prone to blowing head gaskets because the studs are too small to allow it to be tightened down effectively. This was fixed on the Mark 2. It is therefore IMPERATIVE that you use a torque wrench, and tighten the nuts down to the maximum recommended setting (46 lb. ft.) in the recommended order. You must also be sure to tighten down all of the head nuts again after 100 miles. Unfortunately, this entails removing the manifolds. But nobody said life was easy. – Uncle Stan Part)
When the head has been refitted and tightened down, the push rods can be replaced. The push rods are better if kept in order. Fit and secure the rocker shaft assembly, making sure the cups of the push rods are located on the ball pins on the rockers. The rocker pedestal nuts again must be tightened evenly to prevent bending of the rocker shaft.
As the cylinder head, valves and rockers have been disturbed the tappets will have to be reset. There are many different ways of setting tappets, the most popular method being the 13 method. Number the valves 1 -12 starting from the front. Rotate the engine a few times to give the valve and rocker gear a chance to find their natural position and check their action. To set the tappets look for the valve which is open, the one where the spring is compressed, subtract the number of that valve from 13 and that will tell you which tappet to adjust. Slide a 0.010″ feeler gauge between the top of the valve and the rocker. The adjusting screw can be tightened or slackened so the feeler gauge is a slide fit between this valve and rocker. Rotate the engine so the next valve is open and adjust the corresponding tappet; repeat this until all 12 tappets have been adjusted.
Place the manifold gasket onto the studs the correct way round; on close examination it will be found the rear stud hole is lower than the front. If fitted wrongly blowing will take place at a later date. Before fitting the manifolds unscrew the nut joining the inlet to the exhaust manifold. Clean off any remains of the old gasket and renew the carburettor joints. After fitting the manifold tighten the nuts and bolts with their retaining plates, tighten the nut joining the two manifolds. Reconnect the exhaust pipe using a new gasket and if the front mounting has been slackened, re-tighten it. Refit the throttle and choke controls to the carburettor and check their correct function, replace the air cleaner.
Either clean or renew the distributor points, setting the gap to 0.015″ when the fibre heel is on the peak of the cam. Clean and reset the spark plugs and if they show any sign of burning on the electrodes renew them. The plugs should be set at 0.025″.
Replace the spark plugs and distributor top. Make sure the correct lead from the distributor top is connected to the correct plug; this is made easier by marking the leads. Re-connect the H.T. lead to the coil.
Renew the gaskets on the water pump and thermostat housing and refit the pump to the head securing at the same time the petrol pipe and dynamo/alternator stay. The petrol pipe can then be connected to the carburettors. Prime the petrol pump with the lever on the side of the pump and examine for leaks. Examine the radiator and heater hoses for cracks or perishing and if necessary replace them. A light smear of grease on the inside of the hoses makes them easier to fit. Refill the radiator and cooling system with clean water, or with the old coolant if it contains antifreeze and has been kept. Examine the radiator filler cap and check the small valve in the centre. Check the seal in the top of the cap.
Place the fan belt around the pulleys and re-connect the dynamo/alternator stay. Pull the dynamo/alternator away from the engine, this will tighten up the fan belt and finally tighten the dynamo/alternator mounting. Join up dynamo/alternator wiring and temperature gauge.
Before replacing the rocker cover oil the rocker assembly and fit a new gasket to the cover. Do not over-tighten the rocker cover nuts as this will distort the cover and cause leaking.
Check that all items have been reconnected and finally reconnect battery. Run the engine for a little while until the normal working temperature has been reached. All that remains is to tune carburettors.
