Engine diagnosis

Today's update might be a bit boring for the non technically minded although I'm sure my old engineering buddies will be interested.

The nice man from Primrose engineering has stripped the engine and identified the fault as a failed crankshaft journal on the No. 3 cylinder. For those that understand this stuff this is a picture of the underside of the cylinder head and the faulty cylinder is the centre one which has clearly not been firing properly which is why it is so clean compared to the ones on either side which are in good condition.

The journal has been reduced from 50mm to 46mm which is a large enough gap to stop the cylinder firing due to lack of compression and also for the piston to hit the cylinder head on the exhaust stroke, you can make out the bright ring at the 11 o'clock position.

The crank is badley damaged and we cannot source a replacement at present. However, it can be recovered through a process called metal spraying where new metal is effectively added and this can then be machined to the original specification. This is extremely good news as I would be looking for a replacement engine otherwise.

Richard, the engineer, will now go ahead with repair of the crankshaft, check all the other components and replace what needs replacing before rebuilding the engine and refitting to Mr Bunbury. This should take a couple of weeks so I hope to able to continue my travels in early June.

 

Engine update

Having been towed 2 miles off the river into the local (bloody expensive) marina for a mere £360 and have not made much progress in the past 10 days.

Entering the Marina on Tow

 The engineer spent 4 hrs diagnosing the problems and decided that there was a faulty fuel injector pump which needed replacing.  This was not the only fault but he felt it best to start with the small stuff. He returned a few days later to spend another 5 hrs fitting the part and to be fair the engine run a bit smoother but when we took her up the river for a test it was quite clear all was not well as the oil pressure began to fall and there was a distinct big end knock.  Clearly the engine needed to be removed and stripped to identify and repair the fault. Having already run up a £1,500 bill with the prospect of a further £3000 for a rebuild at the Thames hourly rate of £80 I spent the weekend contemplating my next move as I could see this quickly becoming a money pit.

I had lots of advise from the canal forum but of course much of this was conflicting. I basically had 3 options: repair this engine, buy a new engine or buy a second hand engine.  I quickly discarded the new engine option as they are around £9,000 which is a bit outside my range. Used engines ranged from around £1,500 to £7,000 depending on age and model. The boat could be fitted with a range of engines but each would require some modification to the boat to match it up with the drive shaft which of course is more time and money.

I have opted to go ahead with the engine rebuild but instead of using the maria the engine has been collected by a  fellow boater who runs his own engineering business repairing Lister engines. The engine was collected today, as you can see it being lifted into the trailer below.

The engine sees the light of day 

The engine will be stripped over the next couple of days and I should have an idea of costs early next week when they have quantified the work required but I'm expecting it will be below £2000. I have the peace of mind of knowing that the engine is in good hands with a Lister specialist who will not rip me off and does not charge the earth.  I'll update again when I have news.

Engine Trouble

Sorry for the lack of updates but the good ship Mr Bunbury is not well. Coming up the Thames a couple of weeks ago the oil pressure dropped to virtualy zero and the engine became very smoky. I've been in the marina since and after changing a few bits the engineer has come to the conclusion that at least one big end has gone and it needs a full strip and rebuild.

This is something of a setback to say the least as it will take a few weeks and cost an arm and a leg. The blog will go on hold until I'm back on the move, probably by mid June.