Help please - boat engine problems

[stuart]

One for the diesel experts I think.

 

My boat was last used/run about 2 weeks ago without problems and engine ran for a 4 hr cruise okay.

 

Today attempted to start, no problem took a little longer than usual due to the cold but fired up okay.

 

 

However, when increasing throttle (in neutral or in gear) the engine speeds up, seems to stutter, the revs drop slowly then the engine cuts out or goes really "lumpy" where it seems to try and stall.

 

So far I've:

 

Emptied the fuel water seperator (thought that any water in there could be frozen?) - no problem

Checked theres fuel in the tank - its about 50% full.

 

Suggestions of what to try next please?

 

Thanks.

 

PS: Its a 4 year old Isuzu 35lb1 engine on a liverpool boat shell.

[dave moore]

Hi

This could be diesel becoming waxy at low temperatures and not flowing as normal. A diesel fired space heater in a paint dock where I was working yesterday was similarly affected and I was bloody frozen!

Hope this helps

Dave

[stuart]

The emptied fuel/water seperator certainly had a 50/50 mix of water and diesel in it - the diesel was not clear though, a muddy pink colour.

[johnjo]

The emptied fuel/water seperator certainly had a 50/50 mix of water and diesel in it - the diesel was not clear though, a muddy pink colour.

 

How old is the diesel in the tank, could be you have a mild case of diesel bug, and now it's very cold it's made the difference of just being able to flow enough, to can't flow enough.

[Yoda]

It's probably fuel waxing in one of the filters. leave the engine running so that it heats up all around it.

[Guest]

Could be diesel waxing, but this is more normal on road vehicles where wind-chill is a factor. I used to have a Vauxhall diesel that would wax the fuel when moving in very cold weather, but would start again no problems after stopping for a few minutes.

I have experienced red diesel waxing with heating systems years ago, but it was seriously cold, down in the minus tens. I have never known it on an inland waterways boat, but there is always a first time. I would consider changing all of the fuel filters as a matter of course.

[stuart]

According to the thermometer on the boat is was -9 last night, the boats currently stuck in birmingham near sherbourne wharf.p-

[Guest]

According to the thermometer on the boat is was -9 last night, the boats currently stuck in birmingham near sherbourne wharf.p-

At -9 waxing is a strong possibility, especially if there is water contamination of the diesel in the filter. Might just be freezing if enough water present. Lagging around the filters and pipework might help, certainly worked on some heating installations.

[Laurie Booth]

Worth checking all the fuel filters.

I had the same problem on Clarrie and it was the filter in the fuel pump.

[David Schweizer]

I was given to understand that an anti-waxing agent is put into diesel these days, or is that just anothr myth?

[cotswoldsman]

Sounds very much like diesel bug to me.

 

Quote

 

Symptoms for Diesel Bug

 

Engines can function with a surprisingly

high amount of microbial growth in the

fuel, so the chances are you’ll see the

warning signs before it gets to the point

that the engine actually fails. Symptoms

include poor starting, fuel starvation,

erratic running and black smoke from the

exhaust.

 

Unquote

 

Edited to add quote

Edited December 20, 2009 by cotswoldsman

[bottle]

I was given to understand that an anti-waxing agent is put into diesel these days, or is that just anothr myth?

 

I was of the same impression, I also thought it started after the big freeze in the sixties, when it was a 'norm' to see a bonfire under a lorry diesel tank.

[nb Innisfree]

I was given to understand that an anti-waxing agent is put into diesel these days, or is that just anothr myth?

 

Yes it is put in diesel but the prob is we all use 35 sec heating oil (gasoil) and I doubt if it's put in that.

 

When production of gasoil ceases we will all be using diesel complete with anti-waxing hopefully.

Edited December 20, 2009 by nb Innisfree

[Guest]

Yes it is put in diesel but the prob is we all use 32 sec heating oil (gasoil) and I doubt if it's put in that.

 

When production of gasoil ceases we will all be using diesel complete with anti-waxing hopefully.

At one time gas oil appeared to have no anti waxing additive. I cant speak for today. I had trouble with road diesel waxing in the mid 1980's with a Vauxhall Astra. My Mercedes truck never waxed because it had heated fuel lines. Made for much colder climates those Mercs.

[stuart]

I think the last full tank of fuel was not taken from the usual supplier so possible I've picked up the fuel bug - damn! Managed 4 years to avoid that.

 

Is there way to get proof or shall I just clean filters and stick in some chemical bug killer/ cleaner?

[alan_fincher]

I was given to understand that an anti-waxing agent is put into diesel these days, or is that just anothr myth?

 

I was of the same impression, I also thought it started after the big freeze in the sixties, when it was a 'norm' to see a bonfire under a lorry diesel tank.

Not sure if it has changed of recent years, but it used to be the case that even DERV ("white" road diesel) came in summer and winter grades. You didn't order it as this, but that's what you got, if buying from a major oil company.

 

IIRC winter grade in the UK had anti-waxing additives to cover fairly extreme temperatures, (-15 centigrade, I think), whereas summer grade had far less, and was good only to about 0 centigrade.

 

Of course this worked fine in garages and vehicles with a big turn-over, but even if the gas oil, ("red"), you fill your boat with has the same additives added, at the same times, there is every chance you could be trying to operate an engine in extreme winter conditions, but where the tank only contained "summer grade".

 

I'm happy to be corrected if more recent changes in the industry mean that there is less (or no variance) on product spec between summer and winter deliveries, but I'm confident that what I'm saying was certainly true in the past, and might still be so ?

 

However here I'm guessing the problem is the bug, rather than waxing, but that's just my hunch.

[Guest]

Marine 16 appears to get the best results for fuel bug/water contamination treatment. I have used Fortron for a couple of years, and have managed to keep bugs and water contamination under control (we got bad water contamination owing to a leaking deck filler), although when my Fortron ran out recently, I switched to Marine 16.

[johnjo]

Have you tried disconnecting the fuel line from where it connects to the bottom of the fuel tank. There should be a stop tap between the tank and that connection, when disconnected slowly open the tap and see if the fuel runs freely, if it doesn't then I'd assume diesel bug. It forms like a jelly against the outlet in the tank and although you can push a stick or whatever into the tank the jelly closes up behind it.

 

The only way I've dealt with it for instant results is to push a long [at least a metre long, 2mts better] piece of clear plastic hose onto the outlet, open the tap and suck [yuk] you do have to give a strong suck, hence the length of the pipe, but you'll know when to stop, believe me .

 

That should get you going again, I've not found it nescarsary to replace filters, just give them a swish in some clean diesel.

 

Get some Marine 16, it's the best, it'll kill the bug and also dissolve the residue which others don't do.

Edited December 20, 2009 by johnjo

[John Orentas]

Check that you are getting a free flow of fuel through the lift pump, check the internal gauze filter if there is one..

[Roger Gunkel]

It doesn't really sound like diesel bug to me, I've had it several times on my other boat and it has a gloopy dark green mint sauce look to it. If it is though, Marine 16 is by far the best treatment to kill it quickly.

 

The slightly muddy look sounds more typical of very cold diesel, but if you had as much water as you say in the seperater, I think it likely that some has got through to the main fuel filter and injectors. I had exactly that problem earlier in the year with the same symptoms, and a main filter change and bleed quickly cured it. (also on an Isuzu)

 

Roger

[stuart]

As usual thanks for your suggestions folks, I'll swap the filters out and bleed and see what happens.

 

One suggestion here was to seperate the pipe from the tank and see if the fuel flowed freely - I can't do that as the fuel take off is a dip tube into the top /side of the tank rather than a take off point at the bottom.

 

 

 

By the way is there an easy way to get the vetus water seperator bottom container to seperate from the top - damn things so tight !

[Guest]

As usual thanks for your suggestions folks, I'll swap the filters out and bleed and see what happens.

 

One suggestion here was to seperate the pipe from the tank and see if the fuel flowed freely - I can't do that as the fuel take off is a dip tube into the top /side of the tank rather than a take off point at the bottom.

 

 

 

By the way is there an easy way to get the vetus water seperator bottom container to seperate from the top - damn things so tight !

 

Is this the big silver WS180 type? I remove our Vetus one with an old trouser belt wrapped around it and a steel tube with a slot in it to take up the belt. A home made tommy bar goes through the steel tube. Works better than the filter wrenches that I own, and I have a few different types. They are usually very tight. BTW not trying to be patronising, but if it is the WS 180, the bottom bit is a filter that should be renewed; I know of two boats that have broken down because the owners didn't realise this. Again apologes if I am insulting your intelligence, but I just wondered. They are expensive, and some car ones fit, but don't comply with Boat Safety rules. However we carry a couple of car type ones for emergency use.

[stuart]

It looks like the WS180 but I dont think thats the model, I have replaced the filter in the past but its probably due for renewal!

 

I've come across the problem with the car filters as you mention they fit but are usually fitted with a plastic "bolt" on the bottom rather than metal - so fail the BSS.

Edited December 20, 2009 by stuart

[Guest]

It looks like the WS180 but I dont think thats the model, I have replaced the filter in the past but its probably due for renewal!

 

I've come across the problem with the car filters as you mention they fit but are usually fitted with a plastic "bolt" on the bottom rather than metal - so fail the BSS.

There is one car one (Crossland I think) where the bolt from the bottom of the Vetus cartridge will fit, but problem is you still have a (steel) bolt in what is essentially a plastic bottom on the filter. Doubt if a boat inspector would pick it up, but insurance company might in the event of a fire? As an aside the plastic bolt thing in the filter rule is a complete farce, because the flexible neoprene fuel lines would burn away anyway.

[Big COL]

It looks like the WS180 but I dont think thats the model, I have replaced the filter in the past but its probably due for renewal!

 

I've come across the problem with the car filters as you mention they fit but are usually fitted with a plastic "bolt" on the bottom rather than metal - so fail the BSS.

 

Hi Stuart

 

If it has waxed then you will certainly have to change the filter. Filters do not recover properly when the temp rises.

during 79/80/81 freeze we were changing filters around every two days on our vehicles and they still waxed up we would warm the diesel while we changed the filters.

A trick that we used to warm the diesel was to pipe the exhaust with a flexible pipe from the recovery vehicle into the diesel tank of the broken down vehicle and bubble hot exhaust fumes into the diesel. This worked quicker than lighting fires under vehicles and was a lot safer.

In those days we would also add petrol to the diesel tank at a ratio of 40/1 this helped to stop waxing but when you were trying to dewax in temps down to -12c it was hard going and it was mainly at night.