My engine is kaput...

[Boracay]

I checked everything that could be done without spending money.

The symptoms and the age of the engine are consistent with damaged/worn bores and/or compression rings.

The rest of the engine and the gearbox are also in bad condition.

It cost $2,000 + just to find out. Figure $12,000 + for a basic overhaul with no parts support from the manufacturer.

It made no sense to keep the engine when a new one is $20,000.

My wife looked at the large hole where the engine was and said that I should have done it when I first brought the boat.

She's right. It would have saved $3,000 and several months of miserable oily work.

[Alan Wheeler]

It cost $2,000 + just to find out. Figure $12,000 + for a basic overhaul with no parts support from the manufacturer.

Holy Crap. I'm in the wrong country. I should be a Mechanic in Oz.
Wish I could say, arrrr what the heck, the difference is only 8 grand.
One thing though, it shure will be nice to have a lovely new shiney engien down there. So what are you repowering with??

[redjack]

Hello all, this might be a wee bit of topic, but where could i get a dvd on yanmar diesel maintainance you guys are beginning to scare me !! :-)

[seafox]

It cost $2,000 + just to find out. Figure $12,000 + for a basic overhaul with no parts support from the manufacturer.

Cost me $6,000 to find out I was better off with a new one. Managed to sell the old one for $5,000 but would have got close to that without spending the $6,000 on it first.

[cooper]

Cost me $5500Aus for a brand new engine. (Not with gearbox) This is why keel cooling is a good idea. No heat exchanger No extra pumps......Just a standard high quality STANDARD engine.....

[Boracay]

I am just about to put down a deposit on a John Deere 4045 with a ZF63 2:1 gearbox.

I was influenced by all those descriptions of cruisers who had broken down and were waiting for parts in some remote location.

Of all the marine engines one could argue that John Deere has the best parts availability and the same for ZF gearboxes.

[Alan Wheeler]

Cost me $6,000 to find out I was better off with a new one.

Hmmm, I guess Wellingtons closer and at least everyone speaks English. :-)

[sildene]

Just wondering why Alan said (see Quote below) it won't run on Aerostart fumes supplied via the intake manifold.

Nigel Calder, in his book, mentions that "The engine will fire and continue to run as long as the (WD40) spray is maintained".
However, he does state that the throttle must be wide open - so he is implicitly agreeing that the engine won't run on WD40 fumes alone.

There are two things that worry me when I think about this, and I would appreciate any explanations offered:

1) If the air being drawn into the cylinder during the intake stroke, already has combustible fumes (eg. ether) present, why could it not ignite once the piston is in its compression stroke, but before it reaches TDC? My engine has 18:1 compression, but the air could ignite at 15:1 - ie. before the piston reaches the top. And that would be very bad - should snap/buckle the con-rod, yes? ... no?

2) But, if the ether-laden air does in fact not ignite prematurely (ie. only ignites at TDC), then we should be in business - why can't we run the thing by continuing to supply ether fumes to the intake? We have a clear intake passage (tick), a clear exhaust passage (tick), and a combustible gas being compressed (tick). Mr Diesel should be keen to run ... ?



[quote=Alan Wheeler]

To the issue though, if you have no fuel at the injector, you will have no start even with the aerostart.

[Boracay]

Diesel refers to the engine using the heat if the compression stroke to ignite the fuel.

Other forum members may be able to quote actual examples but I believe it is entirely possible for a hot diesel engine to run on the oil fumes from it's crankcase, making it impossible to stop by normal means.

I could always start my engine using ether and it would run, but it spewed oil everwhere and could have stopped permanently at any time. Just no fun at all.

[Alan Wheeler]

[QUOTE]

Originally Posted by Alan Wheeler

To the issue though, if you have no fuel at the injector, you will have no start even with the aerostart.

Where the hell did I ever say that???? It must have been in a different context.
Ether would or should make it fire, but with no fuel the engine would not continue to run of course.
You are right that ether can fire before TDC. That is the negative about it. But if the engine is turning fast enough at time of entry of the ether, then the prefire will still be overcome by the momentum of the engine. The big advantage of Diesels are that they are heavey built and can take some hammering. Ether in short bursts is not an issue to a Diesel. And if it is being used to start, then more than likely the engine is in it's final days anyway.

Other forum members may be able to quote actual examples but I believe it is entirely possible for a hot diesel engine to run on the oil fumes from it's crankcase, making it impossible to stop by normal means.

That'd have to a heck of a lot of fumes :-) Fumes No, but pure oil certainly yes. It is quite common to have engines that are at the end of their lives do this. The blow by builds up so much pressure in the sump that ol is eventually blown up into the oil breather tube to the intake and raw oil enters and the engine can go into run away. It sounds like jack hammers in the engine and the smoke out the exhaust will make any old WW2 smoke screen look lame.

[SkiprJohn]

Aloha Sildene,
I once ran an engine on a mixture of diesel and kerosene sprayed directly into the intake. Indeed it did fire before TDC and after and during and whenever there was enough compression.
It burned the prechambers in the head and destroyed the glow plugs. Not a very good way to get an engine to run.
I would always suggest that you follow the engine service manual to time the injection pump before you try to start any engine. You don't really want to pull the head and replace prechambers and glow plugs. Don't ask me how I know!!!
Kind Regards,
JohnL

[Alan Wheeler]

It burned the prechambers in the head and destroyed the glow plugs.

Yeah go on, tell us :-) You must have run it for a while to do that kind of damage. A simple start procedure won't cause that kinda damage.

[SkiprJohn]

Alan,
I didn't run it for more than 5 seconds at a time for 3 times. It was not pleasant to see the damage. It was a big mistake on my part that I'll never forget. I have to admit it was at the advice of a friend who I thought knew what he was doing. Two glow plugs out of 4 shot and two prechambers that needed replacing. That meant pulling the head, etc. etc..
JohnL

[cooper]

wd 40 is not areostart and vichy verca. wd 40 = super looob. areostart = start ya bastard. I have read about a sailing boat that inverted and the engine kept on running on crankcase oil. Obviously by-passing the injector pump / rack meant it could not be shut off until it used up its own lubrication.

[sildene]

Thanks for shedding some light on my ether-assisted start query, John, Alan and Cooper.

I've since also come across a truck diesel web site where a number of the knowledgeable sounding locals post pretty confidently about using a gasoline soaked rag in preference to both ether and starting fluid. So if you're inclined to have a go, outboard fuel is apparently also a candidate.