Hi Guys, I have just replaced the engine in my 02 955 with a second hand lump due to the crank snapping on my old engine. I have used all the bits off my old lump and have got it fitted, but it won't run. I have a spark, so assume that it could only be the fuel system? When it comes to carbs, I know where I am, but the fuel injection system is beyond me. I have checked and adjusted the valve clearances before putting the engine in the bike. What do I look at next? Thanks in advance. Ian
Think of it as a timed spitter with a pump and valves. The immediate checks are: 1. Is it pumping fuel? 2. Is it damp downstream of the throttle body? (The fuel is atomised so don’t expect wet.)
Ha ha My compression? Question was aimed at what to check next but you asked how he broke the crank before I’d finished typing
Time to download TuneECU and look for error codes. The only thing it won’t show is old fuel! You most likely have blocked injector(s), duff crank position sensor or duff ECU.......or something not plugged in.
What are you getting? Starting System Symptoms: Weak battery symptoms: -- Slow cranking. -- Stops cranking suddenly on compression stroke with button pressed. -- Starts when starter button is released at end of cranking. Repair: -- Charge/Test/Replace battery. Failure Modes: -- Loss of capacity. Appears to charge, voltage good but no reserve for starting. -- Won't hold a charge. -- Low voltage/cell failure. Preventative Maintenance: -- Check fluid levels regularly -- Maintain full charge: Regular riding, trickle charger. Ignition Coil failure symptoms: -- Hard starting/misfiring during cranking. -- Rough idle that can't be tuned out with carb adjustments and carb cleaning. -- Idle misfire clears with new sparkplugs, returns in a few hundred miles Repair: -- Replace: Preferably with Nology for higher reliability than stock Gill coils. Failure Mode: -- Shorted turns in secondary resulting in weak spark. Preventative Maintenance: -- None Testing: Pickup Coil failure symptoms: -- No spark at all -- Spark quits with engine hot, returns when engine cool. -- Note: Pickup coil failure is total. There is no random misfire spark loss. Repair: -- Replace pickup coil Failure mode: -- Thermal intermittant with long (15-30 minute) period. Preventative Maintenance: -- None. Get a spare. Testing: -- Ohms checks hot and cold. Worn starter symptoms: -- Sometimes won't crank until the bike is rocked in gear. -- Excessively noisy cranking with a grinding sound. -- Click from under seat but no cranking. Failure Mode: -- Brush wear progressing to commutator damage. -- Bearing failure related to brush wear. Repair: -- Rebuild or replace. Preventative Maintenance: -- Maintan battery in peak condition. -- Follow proper starting procedures. Neutral, clutch in. -- Crank 5-10 seconds at a time max., switch off for twice as long before cranking again. Worn sprag clutch symptoms: -- Very loud rattling when cranking -- Starter spins but engine doesn't turn Falure Mode: -- Breakage Repair: -- Replace sprag clutch Preventative Maintenance: -- Maintain battery in peak condition. -- Follow proper starting procedures. Neutral, clutch in. Worn starter solenoid: -- Click from under seat but no cranking. -- Won't crank after rocking bike. -- Starter continues to run after bike starts and won't stop until the battery is disconnected. Failure mode: -- Internal contact damage resulting in non-conduction. -- Internal contact damage resulting in contacts welding shut. -- Internal damage/wear prevents solenoid core movement. Preventative Maintenance: -- None. Repair: -- Replace starter solenoid. Testing: -- For no cranking, short across solenoid high-power terminals. Normal operation denotes failed solenoidcontacts. ------------------
The end just fell off the crank. Apparently, it is not uncommon, although, that came from a Triumph engine specialist and not Triumph themselves. I haven't checked the compression, but have stuck my thumb by the plug hole and there seems to be loads of it. I have used all the bits off my bike, which was running a few weeks ago, so assume the injectors are not blocked. Battery is pretty new and fully charged and is cranking nicely.
Fault code check will certainly inform you if something is open circuit (unplugged). After that it's a process of elimination. Engine timing ok,Compression ok, spark ok, fuel delivery ok, good cranking speed ok. Then should fire up unless something related to fuel pressure (too high or low) as mentioned - use fresh fuel. Good luck
Where did you get the engine from Ian? If you’ve used everything from your engine was all the bits missing from the replacement engine I would be a bit suspicious if all the good bits had been removed Unless you know the history of it or know for sure it was a runner
The engine came through eBay. The guy I bought it from assured me that it was a good runner. As seems to be the way with breakers to maximise profit from all the bits.
Tune ECU will throw up fault codes associated with open circuits, failed components etc. Since you have never had it running it is a process of elimination and systematically going through induction and ignition components as well as the physical condition of the top end. You could maybe beg or borrow a compression tester but if each cylinder blows your thumb off it is probably good enough to get it started.