New engine issues

[sighmoon]

For peace of mind, and a view to spending less time and money on repairs, we got a new engine over the winter.

The new engine has given up twice in the marina, and a few times at sea - and no, never at a convenient time.

Each time, the cause seems to be air in it. We've had three new primary fuel filters (and housings) in the last 6 weeks, a new fuel pump, new hoses to the engine and on the engine. Each time it comes away from repairs as good as new for a few hours. The hose into the tank has not been changed as yet, but doing so would require major surgery, and anyway doesn't seem to be the culprit - there are no bubbles coming from the tank.

I'm running out of patience with it.

The installation engineer claims to have fixed it for the 3rd time. Maybe he has and maybe he hasn't. I don't know but I don't feel confident.

I think sailing with young kids and an unreliable engine is pretty irresponsible and I'm not willing to do it any longer.

So what to do?

(BTW, Somebody's going to ask me what brand the engine is, I'm sure. I'm not willing to divulge that at this stage as I'm hoping not to have an antagonistic relationship with the manufacturer just yet. )

 

[Tam Lin]

Is it a red one?

 

[Angele]

Or a green one?

 

[Sandyman]

'' I'm hoping not to have an antagonistic relationship with the manufacturer ''

Why should it be antagonistic? If you contact them & point out your concerns as you have in this post, all in a polite manner, I'm sure they will respond accordingly.

 

[GHA]

So what to do?

One option would be to temporarily plumb a can of very clean diesel straight to the engine bypassing the primary filter.
If it gives up with this then you know the problem isn't the fuel tank or the primary filter but closer to the engine.
If it doesn't give up then try the can straight into the primary filter and try again. Just because you can't see bubbles from the fuel tank doesn't mean air isn't getting in..

Good luck!

 

[earlybird]

One option would be to temporarily plumb a can of very clean diesel straight to the engine bypassing the primary filter.
If it gives up with this then you know the problem isn't the fuel tank or the primary filter but closer to the engine.
If it doesn't give up then try the can straight into the primary filter and try again. Just because you can't see bubbles from the fuel tank doesn't mean air isn't getting in..
Good luck!

+1.
I don't think there's much contamination risk if you're careful since there is probably an engine mounted secondary filter.
Might be best to also divert the injector spill line back to the temporary tank to stop the level dropping too quickly.

 

[pvb]

This is a very tricky situation. With most products, you'd just return it for a refund, but that's not really possible with a boat engine.

First question: did you personally buy the engine and then pay someone to install it? Or did you pay someone to both supply and fit it? If the latter, you could theoretically ask for a replacement installation, but you're unlikely to get it.

It's unlikely to be the engine itself, but more likely to be the associated fittings. First thing I'd do is buy a 25 litre Vetus fuel tank (about £100) and plumb that direct to the engine. If you fill it with supermarket diesel, you needn't worry about a primary filter. Then run the engine at length to check it's OK.

After that, if you think the problem is air getting in, you have to go through the whole pipework, ensuring that all fittings are correctly sealing. The most elusive air leak I ever encountered was a cracked banjo bolt which connected the fuel line to the pickup pipe on the top of the tank. It looked fine, but allowed air to leak in.

 

[Caer Urfa]

Purely a long shot to check as I had months of a similar problems years ago.

We checked everything but finally realized we had installed a new diesel filter higher than the bottom of the fuel tank and slightly further away from the fuel pump.

The pump would run for hours then just shut down, prime it then it would run for another eight hours then shut down.

The problems was caused because the fuel pump was not big enough to suck the fuel from further away plus the fuel filter was not being 'gravity fed' just fuel sucked
through by the pump.

We lowered the fuel filter and moved it slightly closer to the pump and its never stopped since.

Food for thought!

Mike

 

[GHA]

+1.
.....
Might be best to also divert the injector spill line back to the temporary tank to stop the level dropping too quickly.

Very good point.

 

[dom]

Purely a long shot to check as I had months of a similar problems years ago.

We checked everything but finally realized we had installed a new diesel filter higher than the bottom of the fuel tank and slightly further away from the fuel pump.

Interesting, my primary filter is above the 'top' of the tank! I'm wondering if you may have inadvertently cured a little air leak during the re-siting, or perhaps it is still there but too small to leak fuel?

Happy to be corrected here, but I wasn't aware that diesel pumps typicality require the primary filter to be gravity fed and I'm not even sure it would have any effect on the pump as the head would be unchanged.

 

[pvb]

Interesting, my primary filter is above the 'top' of the tank! I'm wondering if you may have inadvertently cured a little air leak during the re-siting, or perhaps it is still there but too small to leak fuel?

That's probably the case.

Happy to be corrected here, but I wasn't aware that diesel pumps typicality require the primary filter to be gravity fed ...

They don't!

 

[prv]

The problems was caused because the fuel pump was not big enough to suck the fuel from further away plus the fuel filter was not being 'gravity fed' just fuel sucked
through by the pump.

We lowered the fuel filter and moved it slightly closer to the pump and its never stopped since.

Maybe older engines had more feeble fuel pumps, but that shouldn't be a problem with the OP's brand new engine. I have a vacuum gauge on my fuel line to monitor the state of the primary filter, so I know that my lift pump will happily pull half a bar of vacuum (it may go higher, I haven't explored the limit). That would be enough to lift fuel from a tank more than five metres below the engine.

Pete

 

[prv]

First thing I'd do is buy a 25 litre Vetus fuel tank (about £100) and plumb that direct to the engine.

A good test - but I'd probably use an outboard tank available for £25 or so from eBay.

Pete

 

[dom]

A good test - but I'd probably use an outboard tank available for £25 or so from eBay.

Pete

As a matter of interest, why not one of those cheap and cheerful 10 litre green metal fuel canisters (those army thingies) which are prob on sale on eBay for about 50p

 

[sighmoon]

First question: did you personally buy the engine and then pay someone to install it? Or did you pay someone to both supply and fit it? If the latter, you could theoretically ask for a replacement installation, but you're unlikely to get it.

The latter. I have asked. We'll see.

Once again, they're saying it is fixed. 3rd time lucky maybe, but by this point I'm skeptical.

 

[pvb]

The latter. I have asked. We'll see.

Once again, they're saying it is fixed. 3rd time lucky maybe, but by this point I'm skeptical.

Ah, right. So if it isn't fixed, it might be worth doing a Small Claims action for a refund. If nothing else, it tends to concentrate attention.

 

[dom]

Ah, right. So if it isn't fixed, it might be worth doing a Small Claims action for a refund. If nothing else, it tends to concentrate attention.

It does, but it can also sour relations which can be somewhat unhelpful.

To be honest once one threatens legal action, one has really got to be prepared to go through with it. Also the OP won't say who the manufacturer is, but I'm sure any of the big boys would lean on a supplier to sort this out ASAP in order to prevent the matter spiraling into a mess. Good business if nothing else.

As there's nothing remotely defamatory been said here the OP might gain more by adopting the middle ground and name the manufacturer, but not the supplier at this stage. That will focus minds for sure as the implied next stop will be him!

 

[Ceirwan]

I had this problem at the start of the season, in the end we traced it down to the fuel intake pipe from the tank letting in air around the threads of the connector. Just something to look at.

 

[pvb]

It does, but it can also sour relations which can be somewhat unhelpful.

I'd imagine that relations are already soured! The installer seems to be clutching at straws - why on earth fit three new primary filter housings in 6 weeks??

 

[pagoda]

I had this problem at the start of the season, in the end we traced it down to the fuel intake pipe from the tank letting in air around the threads of the connector. Just something to look at.

The more connections between the tank and the injection pump, the more potential there is for air leaks. What style are the connections in the fuel line? Have they been over tightened and are now slightly distorted- and pass air at times - interfering with the prime?

When your engine stops, what happens when you manually pump fuel to the input to the main injection pump? Clear fuel quickly or bubbles for ages?