Our 1/8th Off Road team manager - Jon Dell - unboxes the Alpha Dragon III engine and 2134 pipe set and gives an in depth look at the engine and pipe combo thatwill be powering many of our off road 1/8th team this coming season.....
"As part of the new set up for X-Factory UK in 2017, I thought I would put together an unboxing write up on the Alpha Dragon III engine and Alpha 2134 exhaust pipe.
Presentation of the engine has a ‘stand out on the shelf’ look that has really been thought about by Alpha, as has the whole product. The outer sleeve slides off to reveal the engine which is shrink wrapped and the additionally supplied items which are two additional ventrui’s and a P6 plug. The engine snugly sits in its plastic holder giving the impression that it has been secure in its trip from the factory to your workbench. The shrink wrap is a lovely touch meaning that no contamination has entered the engine following its completion.
With the shrink wrap removed and now having the engine in hand, it is nice to find the engine not overly covered in oil. Other manufactures have the habit of liberally coating the engine in oil which whilst this is fine for keeping it shinny and protected, the amount is normally excessive. Unless a full de-coating of the oil is done, first runs of such an engine end with dust being attracted to the oil and a now brown coloured new engine. Alpha have oiled the engine, but with what I would consider to be the right amount, and the outside is not covered in oil.
Dust caps are fitted to the carburetor air filter, fuel nipple, crankshaft and the exhaust ports, however the plug hole is open. Assuming that the piston would have been positioned near the top of the liner to close off the ports and as such the oil stayed in the engine. Another good feature of the shrink wrap would be that the crankshaft would have been held in this position.
The engine is a 3 port design and we know from previous running that the power band is super liner with excellent top end. The range of power available give the reassurance that a number of different engines with different ports to suit different types of tracks is not required. That is, this is a suits all types of track engine, buggy or truggy. A note underneath the engine in the plastic holder provides some critical information on one of the excellent features that Alpha have provided. This engine comes pre run in and only needs a few tanks to complete the running-in process before racing can commence. To do so, I would normally run 2-3 rich tanks on a starter box before heading onto the track for a rich tank full before a race tune. The engines have been incredibly consistent using this method and the time saved is greatly appreciated.
Removing the carburetor dust cap reveals a gold coloured venturi which is marked with 6.5. This being 6.5mm in size meaning the air hole to the carb is reduced to a 6.5mm round hole. As mentioned earlier two additional venturi’s are provided and these are 6.0mm and 7.0mm. This will give a good range for adjustment for future tuning, but so far we have always been happy with the 6.5mm. 7.0mm will provide more power and punch at the expense of less fuel run time and 6.0mm will provide less power and less punch and may provide better fuel run time (although this is not always the case, as less power can result in throttle being open more).
The carburetor is metal bodied with an insulator spacer between the carb and crankcase. The spacer reduces heat from the crankcase combustion chamber to the carb which is the correct set up to eliminate ghost flameouts. Not all manufactures have this feature. The carb is a three needle type, which is a main, bottom end and mid. The bottom end is provided with nicely engraved markings around it so that when tuning, the user can identify how much the needle has been moved. The mid needle is a nice feature, but is one of those things that can over complicate the tuning for the novice. We have found the factory setting of the mid needle to be a very good starting point, with little or no adjustment needed with our Corally fuel.
As is normal the carburetor ball end linkage is held on with 1.5mm grub screw. I always recommend a little bit of lock tight on this screw for security. The carb is held on with a retainer clamp to pinch the crankcase around the carb insulator. Take care to not over tighten the pinch bolt as nipping up is all that is required. Should the carb be removed or moved for your cars linkage set up, always push down fully on the carb to ensure it is fully seated into the crankcase, and then tighten. Sealing the carb to the crankcase is very important as any air leaks will effect the tune and performance. Some racers, like to use a sealant to prevent such air leaks. We have found this not necessary, as the sealing is excellent, but its not a bad practice should you choose to.
I always fit a rubber band to return the carb to fully closed. From the picture you can see how this is fitted. There are two benefits to this, firstly that the throttle linkage return spring can be set as soft as possible so that the carb fully shuts at throttle neutral and allows maximum brakes before the spring fully compresses, and secondly, should a linkage or radio failure occur, a chance for the carb to close has been provided. Having the carb fully shut on neutral is very important, and most poorly tuned or running engines I have seen have nearly always had poorly set up throttle linkages.
Alpha have recently released two new glow plugs, P3 (Hot) and P6 (Cold) and included in this latest edition of the Dragon III is a P6 plug. Different plugs allow for different tuning and performance. The rule of thumb would be that the P3 plug is a hot plug meaning that it operates at a hotter temperature and so would be used on a cold day, and the P6 plug is cold plug meaning that it operates at a colder temperature and so would be used on a hot day. Its not straight forward as that, but that a good train of thought.
In practice, a hotter plug will burn brighter and will allow the engine to idle much better as the combustion ‘bang’ will be ‘cleaner’. The down side is the life of a hotter plug is reduced and as such can fail a lot earlier than a colder plug. A colder plug will be more difficult to tune than a hotter plug, have a poorer idle, but will product more power with a longer life to the plug. Start with a P6 and if the tuning and performance is good with your location, ambient temperature and fuel, then stick with it. Should you struggle with tuning, try a P3. Inspecting a plug can tell you many things about the running condition of the engine. Black with carbon coating the end and wire indicates too rich a setting. No deposits and a dull colour to wire indicates too lean a setting. Shinny and clean indicates good condition and running. Always ensure the plug area is clean of dirt before removal and clean around plug before replacing. Never touch the plug wire as it can become damaged.
Removing the crankshaft dust cover revealed a M3 capped clutch screw and on the end of the crankshaft a clutch bell cone. I would recommend using the correct cone to suit the clutch flywheel being used. There is not an industry standard for cones and its important to match the cone with the chosen flywheel, otherwise, the flywheel will slip. When fitting the cone and flywheel, always pull the crankshaft out towards the bearings. Failure to do this can result in an amount of play on the crankshaft which will allow the crankpin to rub on the backplate. If you have ever removed a back plate and seen scuff marks on it, this is why. Long term this can cause damage or shorten engine life.
Whilst talking of clutches, there are two assembly areas that novices make errors. Firstly it is important to use the correct tools to tighten the clutch nut. The flywheel needs to be gripped vice like, and for this pipe wrenches are ideal. You can get pipe wrenches with rubber or plastic inserts and these are preferred as they do not damage the flywheel. A decent 8mm or 10mm socket is needed to tighten the clutch nut.
Once the flywheel is tightened, shoes and springs fitted, bearings and bell fitted and the bell correctly shimmed, fitting the M3 capped screw with a washer will complete the clutch. The big no no is the use of lock tight on this screw. During racing, you’re going to want to remove this screw on a regular basis. Lock tight bonds the screw into the crankshaft, and if your unlucky the head of the screw will snap off on removal, not good!! Additionally lock tight could run into the clutch bearing resulting in a very early bearing failure. Holding the flywheel with the pipe wrenches and using a quality 2.5mm hex wrench, the correct tightness can be achieved. For this reason 2.0mm headed M3 screws should be avoided at all times. Lock tight on the clutch nut is also not recommended.
Alpha has recently released the 2134 exhaust pipe system which perfectly matches the Dragon III engine. The system uses an inline manifold which connects to the exhaust pipe in the now standard manor. Fitting the rubber gasket to the pipe, and then the 3no springs should be a simple task, just mind hooking your fingers. Another rubber gasket fits to the exhaust port of the engine, and the longer exhaust spring is fitted around the engine to hold the system in place. As good practice I always fit 2no springs around the engine to hold the exhaust, as they can break from time to time. The manifold comes prepared with two sets of holes, so fitting two is a simple task.
An air filter of your choice needs to be fitted as the engine does not come with an air filter. Always ensure the air filter rubber is clean and free of dirt and check for any potential splits. If in any doubt, replace that old used air filter rubber. A new air filter foam should always be clean and coated in premium air filter oil. This is a special type of oil that’s extremely sticky. A nice way to apply this oil is to put the oil onto the foam, and then place the foam into a clean plastic bag. The type of bag that car parts come out of is ideal and freely available. With the foam in the bag, squeeze and work the oil through the foam. With the oil being coloured, you should be able to see it completely covered. Once covered, take the foam out of the bag, place it into some tissue/kitchen towel, and then squeeze the waste amount from the foam. As a means of checking how well you oiled the foam, after used, cut open the foam, if you applied not enough oil, you will fine un-coated areas. If you used too much oil, your see clogs of oil. Too much oil, results in poor air flow, not enough results in dirt going into the engine.
Finally on air filters, if the conditions are wet, either don’t run, or use a wet air filter. This is an air filter that is prepared with a cover to prevent water from getting onto the foam. Should the foam get saturated with water, the water will enter the engine and the engine will not perform or will stop. A wet filter protects water from the filter, but will never make the engine water proof as it has to breathe air into the engine. Fitting a wet air filter does alter the tune, so additionally watch out for this.
Mount the engine onto your choice of engine mounts and your ready to bolt it into the car and prepare for running in. An engine heater will help with this process. Once your running of the engine is complete for the day, always use engine after run oil. Model engine particular after run oil is best if your unsure and don’t use spray oils such as WD40. Some racers will say its not necessary and some say every time. For me its common sense, its not going to hurt and living in the UK, our climate often results in damp air which will enter the engine over time. If your racing and firing up the same engine every week, you could claim not using after run oil is ok, but if your storing for over 1 week, after run will do nothing but protect the internals from rust. The biggest risk is from dirt dropping down the plug hole upon removal of the plug, so ensure this area is clean before removal. Don’t be shy with the oil. 5-10 drops is not enough, 40-50 drops is the target."
Great work Jon...
You will find Jon and the rest of our X-Factory UK 1/8th race team at various events this spring as they prepare for the upcoming BRCA National Series, if you see any of them, be sure to go up and say hello and feel free to ask for any help or advice on any of your Alpha, Corally or JConcepts products