Jump to content

Oil light warning


Featured Posts

Please excuse whatever level of ignorance is evident in the following, but:

 

We were cruising today and after an hour or so, while in a lock, the oil light on my control panel started flickering slightly and chirruping. So when we stopped for lunch above the lock, I checked the oil level, which looked fine. (This, I should probably say, is about the extent of my engine diagnostics and maintenance skills.)

 

Set off cruising again - no protest from the oil light for an hour or more, then it starts up again. Lit up and with a continuous beep when in tickover or out of gear; light goes out and alarm stops when I put a few more revs on.

 

We pressed on for a half hour or so like this to our planned mooring spot, but I'm worried now about running the engine even to charge batteries. Any idea what the issue's likely to be? I guess I'm likely to be phoning RCR in the morning anyway (as it's unlikely to be something I can fix!), but it'd be good to have an idea of what's wrong.

Link to comment
Share on other sites

5 minutes ago, magictime said:

Please excuse whatever level of ignorance is evident in the following, but:

 

We were cruising today and after an hour or so, while in a lock, the oil light on my control panel started flickering slightly and chirruping. So when we stopped for lunch above the lock, I checked the oil level, which looked fine. (This, I should probably say, is about the extent of my engine diagnostics and maintenance skills.)

 

Set off cruising again - no protest from the oil light for an hour or more, then it starts up again. Lit up and with a continuous beep when in tickover or out of gear; light goes out and alarm stops when I put a few more revs on.

 

We pressed on for a half hour or so like this to our planned mooring spot, but I'm worried now about running the engine even to charge batteries. Any idea what the issue's likely to be? I guess I'm likely to be phoning RCR in the morning anyway (as it's unlikely to be something I can fix!), but it'd be good to have an idea of what's wrong.

Which engine is this and what oil is in it. Is there an oil pressure gauge as well as a light. if so what does it read?

Link to comment
Share on other sites

1 minute ago, bizzard said:

Which engine is this and what oil is in it. Is there an oil pressure gauge as well as a light. if so what does it read?

It's an Isuzu something-38... LM38? Oil is 15W 40 Mineral, I believe (changed during RCR service a month ago). No gauge as far as I know.

Link to comment
Share on other sites

Personally I would not run it until you know whats up. What engine? how old or how many hours? When was its last oil and filter change? Its probably the sender (that's the little brass thing that screws into the engine block) it reads the oil pressure and they go wrong far more often than some major engine problem. Whatever the problem it can be fixed

Link to comment
Share on other sites

Well if it is working as it should it is telling you the oil pressure is less than it should be.

It is not surprising it is coming on on tick-over but going out at higher revs, as increasing the revs makes the oil pump work faster.

Either your oil pressure s genuinely low, or the sender that detects the pressure is going faulty, and switching on when it should not.

From memory, if it is working right, many don't come on until the pressure is below 10 psi. That's not a lot, and if that's genuinely the case you need to get it investigated and fixed.

When was the oil last changed ?

When was the oil filter last changed ?

What make and model of engine?

Link to comment
Share on other sites

8 minutes ago, magictime said:

It's an Isuzu something-38... LM38? Oil is 15W 40 Mineral, I believe (changed during RCR service a month ago). No gauge as far as I know.

Good engines. Is there an oil pressure gauge, if so what does it read. Isuzu instrament panels usually have one as well as an engine temperature gauge, if so what has that been reading also.

Edited by bizzard
Link to comment
Share on other sites

1 minute ago, rusty69 said:

Until the experts come along,have you checked all electrical connections including the multi plug if you have one.I assume its the oil pressure warning light (almost sounds like the alternator warning light)

Yeah, all I know is there's a picture of an oil can on it! I've got the instruction book for the engine but not, rather unhelpfully, for the control panel, so nothing to help me interpret the lights.

Link to comment
Share on other sites

Okay, seems clear enough that it's either an issue with oil pressure, or with this 'sender' thingumabob... either way not something I'll be DIYing, so I guess I'll start with RCR and go from there. Meanwhile would I be OK to run the engine for battery charging if I put enough revs on to keep the light & alarm off?

 

3 minutes ago, bizzard said:

Good engines. Is there an oil pressure gauge, if so what does it read.

I refer the honourable gentleman to the answer I gave earlier.

 

And as I say, the engine was serviced (inluding oil & filter changes) only a month ago. It's a well-used engine, 11,000 hours plus I understand, but in very good nick according to anyone who's looked at it.

Link to comment
Share on other sites

2 minutes ago, magictime said:

Okay, seems clear enough that it's either an issue with oil pressure, or with this 'sender' thingumabob... either way not something I'll be DIYing, so I guess I'll start with RCR and go from there. Meanwhile would I be OK to run the engine for battery charging if I put enough revs on to keep the light & alarm off?

 

I refer the honourable gentleman to the answer I gave earlier.

 

And as I say, the engine was serviced (inluding oil & filter changes) only a month ago. It's a well-used engine, 11,000 hours plus I understand, but in very good nick according to anyone who's looked at it.

It could be overheating a little which will thin the oil further and reduce the oil pressure probaly enought to make the oil light flicker, I repeat is there an oil pressure and temperature gauge on the panel please?  If so what were they reading when the light began to flicker.

Link to comment
Share on other sites

If the oil pressure switch / light is telling you the truth, then it probably needs no more than 10 psi of presume before it is extinguishing.

That really isn't a lot on a modern engine, but what you can't know without a gauge is how well it is doing once the light is out.

Running at reasonably high revs just to spin the alternator is probably not going to cause any terminal damage, but I would argue it is less than ideal.

Keep it to a minimum, and get it looked at asap, I would say.

It is quite possibly a faulty switch, and your oil pressure may well be OK, but there is no way of knowing which without further diagnostics..

If you do run it, then please check the light regularly -  if it starts staying on at significant revs, I'd definitely stop to avoid possibly making things worse.

Link to comment
Share on other sites

Assuming that it really is low pressure and not just the sender dicking about. 

Is the tick over sounding any slower?

If your prop paddles in neutral, is there anything on the prop that might cause it to slow the engine?

 

If increasing the revs in neutral stops it from crying  I'd say you could battery charge safely, but then again I would do …… it's not my engine!

You really need an oil pressure gauge to know what's happening further up the scale, which is important when in gear and with the engine working hard.

 

Unlike Listers which can just rely on a piece of paper stuck to the side of the engine with the psi you want drawn on it with a pencil.

Link to comment
Share on other sites

9 minutes ago, bizzard said:

It could be overheating a little which will thin the oil further and reduce the oil pressure probaly enought to make the oil light flicker, I repeat is there an oil pressure and temperature gauge on the panel please?  If so what were they reading when the light began to flicker.

No, no gauge. One of the lights has what could be a 'thermometer' icon on it... but that didn't light up.

5 minutes ago, alan_fincher said:

If the oil pressure switch / light is telling you the truth, then it probably needs no more than 10 psi of presume before it is extinguishing.

That really isn't a lot on a modern engine, but what you can't know without a gauge is how well it is doing once the light is out.

Running at reasonably high revs just to spin the alternator is probably not going to cause any terminal damage, but I would argue it is less than ideal.

Keep it to a minimum, and get it looked at asap, I would say.

It is quite possibly a faulty switch, and your oil pressure may well be OK, but there is no way of knowing which without further diagnostics..

If you do run it, then please check the light regularly -  if it starts staying on at significant revs, I'd definitely stop to avoid possibly making things worse.

OK, thanks. 'Reasonably high revs' would be stretching it I think... I'm only talking about slowish cruising speed, maybe 1000 revs where tickover is 800?

Link to comment
Share on other sites

6 minutes ago, zenataomm said:

Assuming that it really is low pressure and not just the sender dicking about. 

Is the tick over sounding any slower?

If your prop paddles in neutral, is there anything on the prop that might cause it to slow the engine?

 

If increasing the revs in neutral stops it from crying  I'd say you could battery charge safely, but then again I would do …… it's not my engine!

You really need an oil pressure gauge to know what's happening further up the scale, which is important when in gear and with the engine working hard.

 

Unlike Listers which can just rely on a piece of paper stuck to the side of the engine with the psi you want drawn on it with a pencil.

Isuzu engine installations normally have an Isuzu instrament panel complete with oil and temp gauges as well as the lights.

4 minutes ago, magictime said:

No, no gauge. One of the lights has what could be a 'thermometer' icon on it... but that didn't light up.

OK, thanks. 'Reasonably high revs' would be stretching it I think... I'm only talking about slowish cruising speed, maybe 1000 revs where tickover is 800?

Must be quite an early installation with no gauges. It doesn't need to overheat by very much to thin the oil further, enough to reduce the pressure enough to make the light flicker.

Edited by bizzard
Link to comment
Share on other sites

Boat engines come with oil pressure warning senders and lights for a reason. Low/no oil pressure, if left for too long will seriously damage the engine. Potentially thousands of pounds worth of damage. There is, as others have mentioned, a good chance that it is a faulty sender, or a fault in the wiring, but if it is not and you are running the engine, do you want to run that risk? Saying afterwards, "well I just assumed it was a faulty sender" isn't going to help you if the low oil pressure is real. I would suggest that you need the real oil pressure confirmed by someone as soon as possible, with the minimum, or no engine running beforehand.

 

Jen

  • Greenie 1
Link to comment
Share on other sites

As one who 'enjoyed' much the same problem a while back on my Lister LPW4, it did turn out to be the sender installed in the engine that was faulty, so sort of good news. I say 'sort of' because at least it didn't mean a busted oil pump or some other expensive repair job. On the other hand when I called out RCR the engineer's method of identifying the fault was to run the engine and when it showed no signs of slowing, or seizing diagnosed a faulty sender. Because it isn't a part that actually prevents the engine from running, it isn't covered in the RCR spares insurance so I had to stump up £90 (plus VAT) for a new one (it's only a bl**dy switch!?). Part of the reason I'm not with RCR now.

Edited by Wanderer Vagabond
  • Greenie 1
Link to comment
Share on other sites

Allthough the oil pressure is bound to be a little lower than it would normally be on a well used engine with 11.000 hrs on it, due to a general bit of wear on the bearings, oil pump and probably slightly weakened oil pressure relief valve spring. 

Edited by bizzard
Link to comment
Share on other sites

Start the engine when cold. See how long it takes for the oil light to go out. If it takes more than a few seconds it indicates wear. If it stays off when the engine is cold at tickover yet comes on when the engine is hot it is likely due to low oil pressure - probably worn bearings, oil pump etc. Needs checking with a pressure gauge to be sure. Maybe just a lower viscosity oil been used in the last oil change and tipped it over the edge. 11,000 hours without a rebuild could indicate you need one soon.

Link to comment
Share on other sites

57 minutes ago, Jen-in-Wellies said:

Boat engines come with oil pressure warning senders and lights for a reason. Low/no oil pressure, if left for too long will seriously damage the engine. Potentially thousands of pounds worth of damage. There is, as others have mentioned, a good chance that it is a faulty sender, or a fault in the wiring, but if it is not and you are running the engine, do you want to run that risk? Saying afterwards, "well I just assumed it was a faulty sender" isn't going to help you if the low oil pressure is real. I would suggest that you need the real oil pressure confirmed by someone as soon as possible, with the minimum, or no engine running beforehand.

 

Jen

You'll get no argument from me! I'd rather take no chances BUT the same goes for knowingly letting my batteries discharge below 50% by refraining from running the engine at all. 

Link to comment
Share on other sites

3 hours ago, magictime said:

You'll get no argument from me! I'd rather take no chances BUT the same goes for knowingly letting my batteries discharge below 50% by refraining from running the engine at all. 

A bit less life in the batteries is a lot cheaper than a rebuilt engine. Go to bed early :)

 

 

Edited by WotEver
Typo
Link to comment
Share on other sites

1 hour ago, nb Innisfree said:

A known mechanical pressure gauge temporarily  screwed in instead of the sender would decide if the oil pressure is ok or not. 

Agreed, but it assumes OP can identify the pressure switch, and obtain a suitable pressure gauge with the same thread, and then extract one and install the other.

 

I'm not getting the feeling that they have this level of confidence.

Also I don't know this engine, but on some there is not a lot of space, and screwing a gauge straight onto the block might be impossible because it would foul on some other part of the engine as you attempted it.

Sadly though, as already suggested, this will be the kind of thing where RCR think they have wriggle room about what s covered and what is not.  It may well be declared to not be part of the engine itself, but an "accessory".

Link to comment
Share on other sites

The oil pressure sender is likely to be a cheap place to start, but i do wonder if this engine is one that should be run on mineral oil. If it is designed to use a more modern oil i am sure that may be responsible. 

Link to comment
Share on other sites

19 minutes ago, alan_fincher said:

Agreed, but it assumes OP can identify the pressure switch, and obtain a suitable pressure gauge with the same thread, and then extract one and install the other.

 

I'm not getting the feeling that they have this level of confidence.

Also I don't know this engine, but on some there is not a lot of space, and screwing a gauge straight onto the block might be impossible because it would foul on some other part of the engine as you attempted it.

Sadly though, as already suggested, this will be the kind of thing where RCR think they have wriggle room about what s covered and what is not.  It may well be declared to not be part of the engine itself, but an "accessory".

Personally I would persevere with a gauge, maybe one with a remote flexible tube, but then that's me! As you say the OP prob hasn't the wherewithal to do it. 

Link to comment
Share on other sites

17 minutes ago, nb Innisfree said:

Personally I would persevere with a gauge, maybe one with a remote flexible tube, but then that's me! As you say the OP prob hasn't the wherewithal to do it. 

The other point is that you would also need to know what the oil pressure actually should be so if your gauge gave a reading of, say, 12 psi is that OK? or not?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.