Morlock
9 years ago
What are the letters & numbers on the engine Plate?

Should get a date/model from that info.
Andy Mears
9 years ago
Sounds like injector pressure / spray pattern to me - I've got a test pump and go to Barmouth regularly if of any help.
Regards Andy
Tamarmole
9 years ago
Have you got air in the fuel system? Undo the fuel pipe union to the injector and crank the engine over a few times and then reconnect.

Get a blow lamp and warm the air inlet.

Don't use easy start it is the spawn of Beelzebub - engines get addicted to it.
Morlock
9 years ago
"RAMPAGE" wrote:

PS - I think my engine is an AD1.



Found the cold start routine on Youtube



ttxela
  • ttxela
  • 50.2% (Neutral)
  • Newbie
9 years ago
"Tamarmole" wrote:



Don't use easy start it is the spawn of Beelzebub - engines get addicted to it.



I've heard this said quite a few times about diesel engines, I always assumed that what was really happening was an initial problem was not being fixed and getting worse.

I'm told though that over time it can burn the injector tips away.

I remember when I worked on site our collection of antiquated mixers and dumpers always came with a tin of easy start.
tiger99
9 years ago
I used to have experience of small diesels on dumpers, mixers and even concrete vibrators. I doubt that much has changed over the intervening 45 years. Maybe what we used to do, following the manufacturers instructions, will be helpful.

The smallest portable engine had a priming port on the inlet manifold (unifold? only one cylinder!). This had a small plunger with an O ring, which was pulled out, a small amount of engine oil inserted, and the plunger pushed back firmly to spray the oil into the inlet port. Then the flywheel was turned to find TDC on the compression stroke, at which point the injector would squeak. Back and forth for 3 squeaks, then put the rope on the flywheel and give it one good hard pull. If you followed all that, it started every time, but forget the engine oil, to get a good seal on the piston, or 3 injections of diesel, and it would not go. Being a small engine, the spring loaded decompressor was held up only when squeaking the injector, mostly for safety, because a hand was holding the notched flywheel pulley rim, and the engine firing prematurely could mean lost fingers.

At the other extreme, the mobile tower crane had been modded with a 3 cylinder Lister of about 40hp. This one was awkward because the crane slewed from the base, and depending on the wind overnight, the business end of the engine might be over the chassis, providing somewhere to stand, but more often we needed to wedge a length of 4 by 2 in the slewing ring and stand on that. Decompressor pulled, fuel to starting position (maximum), 5 or 6 turns of the handle to inject some fuel, then go at it to spin the flywheel as fast as possible, yank the handle off with one hand, and pull the decompressor with the other, and it always went at first or second attempt.

Downsizing a bit, the concrete mixer has a 2 cylinder Lister, and better working conditions. Again, decompress, wind it round for a few injections, then hard as possible and pull the decompressor. On this one we were more confident of the starting handle freewheeling and detaching cleanly, so it would be cranked through at least one more firing cycle, by which time it would be showing some life. Sometimes a second attempt was needed.

Then the dumpers and circular saw, single cylinder Petters.
Same procedure, wind it around to get some diesel in the cylinder to help the piston seal. However with only one firing impulse every 2 revs it was necessary, after flipping the decompressor, to keep going on the handle for as long as possible. When the flywheel ran out of momentum the compression would make it kick back, fortunately short of the firing point, making these the scariest of them all to start. In one case the handle failed to disengage. Fortunately it was not me that time, but it was amazing to see how quickly people could run!

We never had to use any ether - based starting aerosols, although we had one just in case, in winter. It was more about getting a good piston seal by wetting it with diesel or engine oil. With about 24:1 compression ratio (the little one was even higher) and an injector in jood condition, the diesel fuel should ignite reliably. With lost compression due to piston blow-by, perhaps not.

The other critical thing is injection timing, and unless the engine has a means of retarding the timing to TDC (it will normally be advanced) you really need to get it turning as fast as possible so that the inevitable ignition delay makes the combustion take full effect only after TDC. Too slow and you get severe kickback. You can only get the speed by building up energy in the flywheel for a number of turns.

I imagine that Health and Safety would make most of my former methods illegal today and electric starters would be required.

Funnily enough, in semi - retirement I have a temporary contract working on the electronics for the diesel engines in large trucks. Very different, 6 cylinders, common rail, enormously high injection pressure, turbocharger, powerful electric starter, intake air preheater, no decompressor or manual start capability, and of course a lot more to go wrong...
derrickhand
9 years ago
Slightly off topic, but AFAIK "manifold" is sometimes used to describe any part of the connection between the cylinder head or block, and the fuel injection, air inlet or exhaust system. The number of cylinders is not relevant in context.

The term "stub" is sometimes used to denote a short adapter from a single port to the inlet or exhaust system, although this may denote an integral spigot or flange. Usages vary quite a lot in practice, so go with whatever is used in the Parts Book for your engine of choice!




plus ca change, plus c'est le meme chose
tiger99
9 years ago
Thanks for that, and it could possibly be the inlet stub, except that my memory has clarified slightly and the priming orifice was probably in the cylinder head on the small engine, just above the inlet valve. The stub was between head and air cleaner only on those nifty little engines. They were yellow, and I think European in origin, with the usual tubular carrying frame. I wish I could remember the manufacturer, as they were good reliable little engines, lasting over 20 years on building sites.

They replaced horrid Villiers petrol engines that were delicate, unreliable, and used to crack their carrying frame regularly. I remember welding one or two, also changing bits of carburettor regularly. But Villiers did make some good stuff too.
Morlock
9 years ago
"tiger99" wrote:

They were yellow, and I think European in origin, with the usual tubular carrying frame.



Yellow used to be Hatz livery.

Disclaimer: Mine exploring can be quite dangerous, but then again it can be alright, it all depends on the weather. Please read the proper disclaimer.
© 2005 to 2023 AditNow.co.uk

Dedicated to the memory of Freda Lowe, who believed this was worth saving...