Help. Lister SR3M not starting.

[nickcirrus]

Hi everyone. Am new to this forum but not so new to lister engines.  I have run a lister SR3 on  my boat for 15 years and striped it down several times. Last year I bust the connecting rod on no 3 cyl. Thought I would do a recon and replaced all 3 pistons with aftermarket ones .002 oversize, that come from India along with 3 new con rods and big end bearings. As the cylinders were a bit short of cooling fins I also bought 3x 2nd hand re bored cylinders. All fitted and reassembled with reconditioned injectors. Spent nigh on a week trying to start her but barely a pop! By the end of the week I had had enough. Stripped her down again and double checked, noticing the throttle link arm had slipped off its cam just before the fuel rack. Also checked the timing marks on the gear trains and reset the fuel pump marks on the rack. Still no start. Decided to have a go at timing the fuel pumps. Hmm, when I set no 1 piston to TDC I was finding the no 3 mark came up on the flywheel! Removed gear train cover wondering if one of the gear train keys had sheared and the gear slipped. Removed the crankshaft gear, but that was ok. The camshaft gear key way seemed fine as it lined up with the keyway on the camshaft extension. Rechecked timing marks and none correspond to the piston positions! Could it be that the flywheel is from another engine and was never remarked? Or could the flywheel have sheared its key and slipped on the crank shaft? Perhaps the sudden stoppage under load when the con rod broke caused this. In any case that should not stop it from starting unless the flywheel is spinning free which it is not. So my friends why will it not start? I know the piston rings have not fully bedded in yet. I tried fan heater, hot air gun and flame in the intake but no joy. The suggestion is that something else may have happened as a result of the con rod failure. But there is nothing else that I can think off. As I found the timing difficult to do I removed a shim from each fuel pump to see if advancing the timing helped. no luck there either! So where do I go from here??

[dieselgman]

Nick,

I would start with the basics... is fuel getting through the entire system? Are your injectors creaking (opening)? What kind of compression can you feel when rolling the engine over? Can you feel any two-way air exchange in either port when rolling the engine at cranking speed? Re-check your valve adjustments.

These engines will generally start even with timing off quite a distance... but you will no doubt need to re-set the whole works. Start with TDC #1 and confirm timing marks on cam gear and crank pinion align, then look at cam lobes (both should be in about a 30 degree down angle), at that point the flywheel markings for TDC #1 should also align. The other cylinders will then follow without any trouble.

dieselgman

[listard-jp2]

Hello and welcome to the forum.

You obviously know a bit about Lister engines, as you have given a fairly concise account of what you have done.

From what you have stated I have the following observations:

When you stripped and rebuilt the engine, did you measure and set the bumping clearances, because if this is not correct then it will have a dramatic effect upon the ease of cold starting your engine.

Its quite possible that the flywheel fitted to your engine is say from a 2 cylinder engine, which as you have already identified would cause the mismatched timing mark problem. If however you can see 3 TDC marks on the flywheel (then its the correct flywheel for the engine), and hence the flywheel will have moved on the crank, and sheared the key.

As you have had the injectors reconditioned, can you hear them creaking whilst turning the engine over?

One final point I would raise, are the pistons fitted the right way round, as the combustion chamber is offset, and piston orientation is crucial (it is even marked as such on genuine Lister SR pistons). If not fitted correctly you will never be able to hand start your engine.

Let me know how you get on, and report back.

[nickcirrus]

thanks Listard and Dieselman. All three markings are on the flywheel but none correspond to TDC for no1 cyl which is at opposite end to flywheel. Timing marks on gear train match up with No1 TDC. The flywheel may have slipped some but engine cranks ok so that should not stop her starting.
Thought about the combustion chamber on pistons which as far as I know should be on the injector side to the engine, so the chamber is beneath the injector nozzle. Might take a head off and check yet again! Done the bump clearance. Might check that again too I suppose. Injectors creak ok. Bled the fuel countless times. That is not normally a problem as the tank is higher than engine. Compression feels much the same as before. Frankly I am baffled. I wonder if had I simply replaced only the broken con rod and nothing else perhaps it would have fired up no problem.

I am miffed by the markings on the flywheel not lining up, but do not recall noticing that when I replaced the piston rings ten years ago, though timing was not an issue then. Not keen on removing flywheel to check keyway as I will have to remove the gearbox and reduction gear. I can imagine that it is possible the key sheared and the flywheel has shifted on the crank from the momentum when the engine suddenly stopped, so perhaps the heavy flywheel kept going some! but I would think that the crank shaft would be more likely to break. In any case as I am still able to crank the engine round that should not make any difference. Several people have suggested that at some time in the past the flywheel has been replaced. As I write something tells me that I may have to pull off the flywheel just to find the answer anyway. It may well be tight enough to start up with the starter motor but may free up when under load and running and could cause havoc. How I wish the engine sat on a bench instead of in the cockpit of my boat!!!!

Any ideas gratefully accepted.

[dieselgman]

Those flywheels are tighened onto a tapered cone on the crankshaft and generally bullet-proof even under catastrophic engine failures. I suppose it is possible it could have sheared the key, but that is highly unlikely. The key is just there for initial alignment, it does little to secure the flywheel as that is accomplished by the precision taper fit and quite substantial locking torque.
Do you have your workshop manual handy? Does your configuration match what the manual shows? Where is #1 piston when the TDC #1 mark on your flywheel aligns with the pointer? Remember this mark will come into alignment once per crankshaft revolution but twice per camshaft revolution so it is possible to get things a bit confused (180 degrees out). Your camshaft timing and gearing is in a 2:1 ratio to the crankshaft.

I would have you start the diagnosis with a definitive answer to the above questions and we can step forward from there. This may render pulling the flywheel unnecessary if it has not moved on the shaft.

dieselgman

[dieselgman]

Nick, you are correct that the combustion chamber offset in the piston crown is towards the camshaft (or injector) side of the engine.

dieselgman

[nickcirrus]

Dieselgman, i am glad you said that the flywheel is unlikely to come loose, besides which, it is not a high revolution engine and therefore when the con rod broke, and engine stopped, the flywheel inertia would not be that great,

I have wondered about being 180 degrees out. Yesterday i went through all the markings on the flywheel  and put paint on them to highlight them, then went through each cylinder and none correspond to TDC on any cyl.  Only the marks on the gear train match up with TDC no 1.  I understand the 2:1 ratio is the other stroke up to TDC which would be the exhaust stroke before the inlet valve opens. It was a bit wet yesterday so did not go down. But today I will go down and  "give her a coat of looking at" again. I am prone to moments of great stupidity and concede I may have overlooked something very obvious, but what really bothers me is, even if the markings are out, for what ever reason, the engine has always run fine, then the con rod breaks and I replace it, but now she will not start! When I stripped her down after the failure all I found was a busted con rod and the skirt at the bottom end of no 3 cyl was a bit shattered. Nothing else appeared to be wrong. She cranks round well enough to start and the fact that the markings on the flywheel are wrong would not affect the starting/timing in any way other than If I had set up the valve clearances to correspond to the flywheel markings rather than simply looking at when they open and close. There is nothing else in the engine that I can think of that might have changed or be damaged to affect the starting.

Well 'once more unto the breech' my friends and this time I will put on my x-ray specs and make logical observations with book in hand (all ten pages complete with misprints!), make notes and report back!

[listard-jp2]

As you rightly state the engine ran fine before the connecting rod, and irrespective of the timing marks on the flywheel this would not effect the starting of the engine.
Furthermore you had prevoiusly stated that you removed shims from under the injection pumps, depending on the amount you removed this would firstly take up wear that normally occurs any extra would then advance the timing (hence making it easier to start, but more noiser).

You can check valve timing without recourse to the flywheel marks, by observing if the inlet and exhaust valves rock over on TDC.

The problem I feel lies with the items you have changed, you say your using Indian pistons and rods (how do they compare dimensionally with the orginals in terms of compression height of the piston, centre distances on the rods etc).

Finally: I know this sounds daft, but I have known it to happen, are you turning the engine over in the right direction, ie is your engine electric start, and your using a borrowed handle of the wrong hand to turn it over?

[dieselgman]

Very interesting point Listard! Yes we have run into this exact thing before with an incorrect rotation starter that was swapped without the full knowledge of the customer. Make sure it is rotating the correct direction! 

Funny how some things can escape the memory! 

dieselgman

[listard-jp2]

Very interesting point Listard! Yes we have run into this exact thing before with an incorrect rotation starter that was swapped without the full knowledge of the customer. Make sure it is rotating the correct direction! 

I remember this point well, as when I was a plant fitter back in the day when nearly every Lister and Petter diesel engine was handle start.  Clockswise start Lister LD1 and latterly LR1 engines were fitted in Benford 5/3 cement mixers (the Petter option was the PAZ1 engine, which this worked equally well on). A favorite trick would be to get the new apprentice to try and start the cement mixer using a handle that had being doctored and had the pawl mechanism reversed [making it suitable for use only on an anticlockwise rotation engine]. After about 1/2 hr of letting him wind it over, we would then go and start it in front of him using another handle (which was of course the correct rotation), then stop the engine, and invite him to try again using the doctored handle we had prevoiusly given him. This could go on all afternoon with some apprentices (even after they had noticed that smoke was coming out of the air filter) 

[dieselgman]

Well that is just Brutal!  I guess the lesson would be well learned though! 

dieselgman

[nickcirrus]

 :)Could be a eureka moment coming guys! Whilst I reckon the indian stuff I put in is reasonable, their stuff must make their gen sets work, and 'lord knows, there's probably quite a few over there, I can't help wishing I had bought genuine Lister parts. But hey the starter motor may well be an issue! I had to lift the engine up some 10 inches into the cockpit just so as I could access it all without having to chop my legs off! That meant I had to disconnect the starter motor. No crank by the way. It may just be I have connected it back up with the wrong polarity and it now turns the engine the other way round. Mind you, not sure if a DC starter motor can be turned the other way just by putting the wires on the wrong way round but it is worth a check. And I will then take a running jump at myself if you are right. Really hope you are.

[dieselgman]

Best of luck with that test!

dieselgman

[nickcirrus]

Sadly have to go out today so no time. Fingers crossed will look tomorrow. Thanks.

[nickcirrus]

Guess I'm not so dumb after all.  Sadly the rotation is correct with the hand book, which is clockwise looking at the flywheel end for multi cyl engines. Had me looking less glum for the day but just checked. The wires wont reach the other way round! And of course flywheel rotation was correct. Apart from the flywheel markings anomaly  I can think of nothing else to look at. Think I might as well put the gear train cover back on, go through the timing again. With the injectors out I can use a thin screwdriver to check TDC and also observe the valve timing etc. Noticed diesel squirting out of injector pipes as I cranked her round this afternoon, so that is good. The only thing I cannot check is the compression. I do not have the tools and not sure if it's possible  to do that on these engines. However it feels no different from before when I turn her round with a pipe wrench on the camshaft extension. The cylinders were 2nd hand and re-cut to take oversize pistons by the guy that sold me the pistons. One would hope they mach up!