Will I need a new engine.

[Theo]

No. 1 son took his family for a four day cruise.  He rigged the anchor saying "We'll never use that."  before setting off down the river.  After a couple of hours the engine seemed to lose power and then stopped.  The starter motor could turn the engine which fired but could not keep going.  Anchor deployed and waited to be rescued by a passing boat.  Towed to a safe mooring.  I went down to see him this morning and have listed below the signs of engine sickness:

 

1. During the progressive failure no overheating detected.
2. No excess smoke.
3. Fairly rapid loss of power.
4. Starter motor had difficulty turning the engine over.

 

I checked the following when I got to the boat

 

1. Battery voltage: OK
2. Alternator free to turn: OK
3. Propeller and associated transmission free to turn: OK
4. Crank shaft free to turn?  (Spanner on the nut at in the middle of the pulley)  Wouldn't budge.  Seized, no rotation, not right!  Aargh!!

 

I have inferred from this that our BMC 1.5 which has been 100% reliable over nearly 6,000 hours of cruising since we bought her in 2006 + whatever hours she had done from 1983 to 2006.  (OIl and filter change about 200 hours previously.), that the oil pump failed so there was no lubrication of the crankshaft bearings or big ends or whatever else is fed with oil from the pump.

 

Is my inexpert inference likely to be correct?

 

I now need to make somes decisions in consultation with my sone and his family who want to take ove rthe boat and I am getting a bit on the ancint side.

 

• Repair that engine.
• Get a reconditioned BMC 1.5 from Calcutt or somewhere else and have it fitted by a professional.
• Get a different, more modern and quieter deisel engine and mount it in a more conventional way.  This would mean a new propeller as the present on is left handed and I would like to turn the engine around rather than continue with the belt drive.
• Fit an electric drive system (series hybrid)   This is a pipedream sort of idea from my son  it sounds a very expensive option to me.  Guesstimates of the issues and costs gratefully received.

 

The current cooling is indirect raw water.  I like this and would like any replacement deisel to use the same system.  It has never given us any trouble and if this can be done won't need a skin tank to be fitted.

 

What do you think?

 

Nick

 

 

 

[Tony Brooks]

It certainly sounds like a seizure, but not sure about a failed oil pump unless the skew drive gear stripped. It shares the skew gear on the camshaft with the injector pump and if the oil jet and strainer have not been regularly cleaned the injector pump drive can damage the cam shaft gear. The other possibility is that the oil pump strainer has blocked, but none of this can be easily checked without the sump off.

 

From what you say, I suspect that a rebuild/repair will be the cheapest option in view of the belt drive etc.

 

Try loosening the injectors and trying it over in case water has got into the bores and caused a hydraulic lock.

[booke23]

It does sound like a seizure, but I'd expect some big end knock if the engine was run for a prolonged period with no oil pressure. Even if it didn't knock there would be signs of big end bearing distress in the form of metal fragments in the oil, so examining the oil is another thing you can do to try and diagnose the problem. Is there any play at all in either direction when you try turning the engine via the pulley nut? If so that could be big end bearing play which would be a bad sign. 

 

You mentioned the transmission turned freely, presumably at the output shaft. Although unlikely, it might be worth ruling out the input side of the transmission too, which will involve removing it to be sure. Of course if the transmission did suffer a failure like this, it's oil will likely be full of metal bits too so you could drain that and examine as a first step. 

Edited August 26 by booke23

[Tony Brooks]

 The apparent lack of any excess noise just before the engine stopped seems odd, unless it is a piston seizure, but then I would have expected a bit of a squeal.

 

I wonder if the timing chain has jumped, so a valve has hit a piston. @Theo did you try to turn the engine both ways?, If not, try it, because if something has hit the piston it might turn backwards.

 

Stopping as described would initially point to fuel, but it seems to be seized, so a mystery.

Edited August 26 by Tony Brooks

[agg221]

It definitely sounds like a seizure and my guess is within the engine, although the advice to check for metal in the engine and transmission oil will soon tell you which. There is nothing to be lost by checking Tony's suggestion as to whether the engine will turn backwards, but the symptoms as described don't look right to me for a timing issue as it lost power rather than coming to a dead stop.

 

In terms of what next, I would be inclined to start by getting this engine diagnosed and then form a view on whether to get it repaired. It has been reliable, the fact that you know service intervals for oil suggests it has been properly maintained and as such it is a known quantity apart from the current issue. If whatever it is can be resolved without a complete rebuild then I would stick with what works.

 

If not, I would be inclined to stick a rebuilt engine in. This is for several reasons. Firstly, you know the make/model works with this boat and it fits the existing mounts and prop. Secondly, anything else is going to be a more major investment. The fact that you are planning to hand the boat over to your son means he may want to make changes anyway and it would be better if he does that from a sound basis. Thirdly, it gives the quickest resolution. That means the boat will be up and running for the remainder of the time you are using, it rather than you effectively spending your handover time in modifications.

 

Once it is your son's, he is of course free to make whatever changes he likes, but you can be confident that it is on a sound footing to take forward if the engine is either repaired or replaced like for like, whereas any greater changes open up the potential for ongoing problems which you may feel some level of responsibility for (e.g. a not quite correct installation that eats engine mounts, a serial hybrid design that doesn't quite have the power calculations right etc), that could detract from what should be a pleasant handing on of the boat. Easier for relationships if it is a clean transfer.

 

Alec

[MtB]

15 minutes ago, Tony Brooks said:

Stopping as described would initially point to fuel, but it seems to be seized, so a mystery.

 

That's what I thought too. Water in the fuel specifically. Especially from this comment: "The starter motor could turn the engine which fired but could not keep going." I guess if a main bearing had picked up and seized, the starter motor might actually be able to deliver more torque than a cylinder firing and perhaps overcome a seized bearing, but I don't really know. 

 

@Theo it takes quite a lot of pressure on a spanner to make a cold engine turn. Could it be you just weren't pushing hard enough? 

 

 

[jim mitchell]

1 hour ago, Tony Brooks said:

Try loosening the injectors and trying it over in case water has got into the bores and caused a hydraulic lock.

I would do this first too -  it makes it far easier to turn over by hand and will confirm if its seized solid or not before stripping parts to look for debris resulting from a seizure.

[magnetman]

1 hour ago, booke23 said:

 

 

You mentioned the transmission turned freely, presumably at the output shaft. Although unlikely, it might be worth ruling out the input side of the transmission too, which will involve removing it to be sure. Of course if the transmission did suffer a failure like this, it's oil will likely be full of metal bits too so you could drain that and examine as a first step. 

I have seen a Hurth manual gearbox lock an engine up from the input side. It took a while to free it off. It was a Beta Marine 1.5 and a Hurth box not sure what number. One day it stopped dead and stalled the engine. Freed it off by turning the crank shaft nut back and forth for a bit. 

 

 

[MtB]

1 minute ago, magnetman said:

I have seen a Hurth manual gearbox lock an engine up from the input side. It took a while to free it off. It was a Beta Marine 1.5 and a Hurth box not sure what number. One day it stopped dead and stalled the engine. Freed it off by turning the crank shaft nut back and forth for a bit. 

 

I haven't seen this installation but being a belt drive, the gearbox may well not be on the engine.

 

If there is a gearbox at all. 

[Theo]

Hugely helpful comments, thank you.

 

There was some squealing, which Jilly, Andrew's wife, noticed.  She thought that it might be an alternator problem.

 

I'm about an hour and a half away from Theodora, unfortunately, so I won't be able to carry out the investigations for a bit.

 

I'm minded at this stage to get it to a boatyard and let the experts take over.

 

N

[MtB]

8 minutes ago, Theo said:

get it to a boatyard and let the experts take over.

 

 

I'm not sure those two things necessarily follow....

 

 

Edited August 26 by MtB

[jim mitchell]

13 minutes ago, Theo said:

 

I'm about an hour and a half away from Theodora, unfortunately, so I won't be able to carry out the investigations for a bit.

 

I'm minded at this stage to get it to a boatyard and let the experts take over.

 Could No 1 son do the initial bit - if he's going to take over the boat while its trouble now it could afford him a good learning opportunity - afterall if its a replacement type job there can be little extra damage done 🤔

[booke23]

1 hour ago, MtB said:

 

I haven't seen this installation but being a belt drive, the gearbox may well not be on the engine.

 

If there is a gearbox at all. 

 

Good point.....I assumed the belt would be on the output side of the gearbox but who knows.  

[Theo]

Hello again.

 

The engine has been removed by Jason Pinder in Worcester.  He took it over to Calcutt and the work has been done by Roger Preen and his mate(s).  Roger sent me an email today to tell me that the works has been done.  Here is the text of his sort of diagnosis.  I still can't work out why it failed but then I don't understand the term "pick up" on a big end.  He writes 1.8 in the las sentenc but that is a mistake.  It's a short 1.5.

 

Dear Nick,

  There was general wear ,as you would expect, but the failure was a seizure, of a main bearing  and a pick up on a big end rendering a crankshaft  replacement  necessary together with appropriate new shell bearings and thrusts, the damage suggests a breakdown of lubrication, the oil pump was replaced but was not the problem neither was the pressure relief valve  or any part of the oil train, the  rear cam shaft bearing was slightly misplaced but  this would only affect the valve train in which no significant wear was found, all camshaft followers were replaced, but this is  always usual on the 1.8. I  will send the “pick list” of what we used

    Best Regards

        Roger

Any comments?

Nick

[Tony Brooks]

I am sure Roger checked this, but as it is a 1.5, when the injector pump skew gear drive lubrication system blocks the skew gear can wear. One of the skew gears that drive the injector pump is on the camshaft, just in front of the rear bearing, and it is the same skew gear that drives the oil pump skew gear. You may wish to confirm that the camshaft gear was in good order.

[Batavia]

Pick up = galling.

[hider]

16 minutes ago, Batavia said:

Pick up = galling.

Not just galling, damned annoying and expensive!

[Theo]

1 hour ago, Tony Brooks said:

I am sure Roger checked this, but as it is a 1.5, when the injector pump skew gear drive lubrication system blocks the skew gear can wear. One of the skew gears that drive the injector pump is on the camshaft, just in front of the rear bearing, and it is the same skew gear that drives the oil pump skew gear. You may wish to confirm that the camshaft gear was in good order.

Roger says:

 

The Camshaft is carefully checked, Tony is quite right, the skew gear can wear although the cross shaft driving the FIP has a pin drive to the female spline for the pump and the pin can get worn, we check this!

 

This is comforting to know but doesn't  solve the mystery.

[BEngo]

So, both a main bearing and a big end bearing have failed.  As Roger Preen has said, that means they were not getting enough oil.

 

Commonest cause of not enough oil at the bearings is insufficient oil at the pump strainer in the sump.  How much oil was Jason Pinder able to drain out?

How much sludge was in the sump, reducing its effective capacity  but looking OK on the dipstick?

 

Other possible causes include a bearing shell rotating, which blocks the oil supply (but is not likely to happen to two bearings at the same time), blockages, or restriction of the oilways and general wear and tear of the oil pump.

The first two are not likely to be detected as part of a non- forensic teardown.  Bearing shells often stick on dismantling, oilway condition is  not investigated-  the oilways are just cleaned to remove any melted bearing.

 

N

[Tony Brooks]

If run for long periods without oil changing, with low oil and insufficient oil cooling, I have known the strainer to block. However, I can't see that happening on a canal boat with a reasonably knowledgeable owner.

[magnetman]

The BMC 1.5D have been known to have issues with fuel diluting the lube oil leading to thin oil which could potentially cause seizing. 

 

 

 

I was told once that if an engine is inclined slightly as in the front of the Boat being up a bit there can be lubrication issues at the front end of the crankshaft. Being pressure fed it doesn't fully add up but one wonders if the Boat in question is up at the bow and the failure was at the front end. 

 

Gravity does funny things sometimes. 

Edited October 1 by magnetman

[hider]

4 minutes ago, magnetman said:

The BMC 1.5D have been known to have issues with fuel diluting the lube oil leading to thin oil which could potentially cause seizing. 

 

 

 

I was told once that if an engine is inclined slightly as in the front of the Boat being up a bit there can be lubrication issues at the front end of the crankshaft. Being pressure fed it doesn't fully add up but one wonders if the Boat in question is up at the bow and the failure was at the front end. 

But the engine is in back to front!

From my experience fuel dilution of the lube oil is unlikely to cause a bearing failure. It is more likely to cause the engine to run away and suffer an explosive mechanical failure first.

[magnetman]

Maybe there is some sort of lube oil starvation at one end. 

 

I had a dilution runaway on an SR2 in 1994. My first canal Boat. Rugeley railway bridge. The smoke was amazing. Fortunately the unit still had decompressors. 

 

Prior to the runaway the engine was misbehaving and tending to seize a little bit when running at tickover. Thin oil. 

Obviously 'seizing' usually means it locks up but it can be a tightening and general reluctance to turn. Maybe this could be followed by bearing failure if the engine was allowed to cool partially seized then started afterwards. 

 

 

I'm thinking about general lube oil consumption v small Diesel leak balancing each other out and not being detected on the dipstick over time. It could happen on a regularly used slightly worn engine I reckon. 

[john.k]

Ive seen Perkins diesels with fuel running out the dipstick and zero oil pressure ,owner admitted to using 90 grade gear oil to try to combat dilution .......yet  once the fuel leak in the DPA pump was fixed ,the engines ran without apparent problem............my own Perkins 510V8 was running fuel out the top of the motor ,due to a failed lift pump diaphragm,yet when this was fixed,it ran with normal oil pressure for many years...........However ,when the Fordson Super Major Diesel tractors came out,they had bearing failures and seizures from the internal fuel injectors leaking........GM s are notorious for massive failures from fuel leaking from injectors.........So it depends on the motor.