Thursday, 27 March 2008
Wednesday, 26 March 2008
It's not that I haven’t been doing anything either. I’ve been doing bits here and there, plus a bit of socialising. I can’t spend all my time in the garage being "Billy –no mates".
The main thing of note is ‘pistons and liners’.
I want to try to keep the engine as original as possible (I may have mentioned this before - yawn). Anyway – to cut a long story short, Jim and Sarah of NB Warrior fame very kindly offered me Warrior’s old pistons and liners if theirs were better than mine (they had all of theirs replaced with new shiny alloy ones when RN re-built their engine).
Plans were made and we decided to attend a CWF Banter at Napton (last Monday). Pistons would be compared and exchanged there. As it happen, I went to the boat gathering at Stoke Bruerne on the Sunday, so did Jim & Sarah, and the exchange took place in the Museum car park.
A few other bits finished off now are the rocker covers and the cylinder head air intakes.
They where a real pain to clean up and paint, but they look nice now.
Hopefully I’ll hear back from PRM soon about the gearbox and coupling arrangements, I can then get the crank etc sent off for machining. It’s sat in the garage at the moment ready to go.
Sunday, 16 March 2008
Well, all of the household were out that night, so there was no time like the present. A few text’s later and we arranged to meet that night on the boat and then retire to the pub. It seemed like a good plan.
It ended up as a very pleasant evening in the company of Keith and Jo, plus fellow bloggers; Bones http://mortimerbones.blogspot.com/ and Maffi http://www.narrowboater.blogspot.com/.
Being as it was dark and all that, I returned the following morning to talk engines and stuff with Keith.
The tittle of the post – ‘Inspiration’. A couple of hours with fellow Narrowboaters and vintage engine enthusiasts does help now and then. The sound of their DA makes you want to come back and get on with your own project.
Onwards and upwards!
Saturday, 8 March 2008
Amongs't the ramblings of an excited woman ;-) she bought up the subject of the number(s) stamped on them (check out the comments).
Well, my injectors are all stamped with:
56214 is my engine number, so:
I don't think you can see it very well in the photos, but its on the 'flat bits' at the front of each one.
Sunday, 2 March 2008
I remember many years ago an old engineer (before I became an old('ish) engineer) telling me, "a piston will tell you what an engine has been doing and how its been looked after".
So, I present my piston(s) - well one of them (but the other two look very similar).
The piston assembly consists of a separate housing for the big end bearing. This in turn is bolted to the bottom of the connecting rod with the piston at the top.
From the next photo, you can see that the rings are badly gummed up and tight in the grooves. The residue is quite sticky. The problem with this is that the rings are not/have not been doing their job properly. They should be free to allow them to expand out and make proper contact with the wall of the liner. Judging by the state of the pistons, I expect that the engine had been difficult to start and would have been quite smokey. The lower and upper oil rings wouldn’t have been doing their job and I sure some lub oil would have been finding its way in to the combustion chamber and some of the products of combustion finding their way in to the crankcase.
Although its not very clear, the bottom of the piston crowns are also very carbonised and sludgy. This would indicate that the pistons were not getting very hot ‘in use’.
So what would the ‘old engineer’ make of this. A typical cause of this type of problem is lack of use, only being used for short periods of time or the engine never reaching its working temperature/lightly loaded.
A scenario that meets this? A standby generator? Spends a lot of its time idle. When it is run, it’s only for relatively short periods of time (‘on test’). Light load – standby generators are rarely loaded when being test run (bad practice). All of which lead to the engine never reaching its proper operating temperature.
So, is that what the engine was used for? It ties in well with the four groove ‘V’ belt pulley that was bolted to the original flywheel. The engine was hand start only, so if it was a ‘standby power generator’, it wasn’t for critical plant. I’ll probably never know for sure, but it’s a bit of engineering forensics!
Next will be to de-gum the rings and clean up all of the grooves. I would really like to be able to reuse them as the alternative would be RN's alloy units and that has a whole load of other knock on requirements.