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Hello members.

Please advise.
My new boat has had a hemorrhage.
Oil alarm came on after a kilometer's motoring at high revs. 
Pressure had been high each time I ran it for the couple of times that day. I didn't wait nor see the gauge return to normal operating level but did notice that it didn't fall back.
The question is: What can happen to keep the pressure high?
At the alarm of course pressure was zero.
And the remedy please.
Methinks could simply be loose oil filter (was easy to remove) though surely that would reduce the pressure in the engine.
Will start by adding oil and a new filter and run the engine to see if pressure returns while looking for leak areas. Otherwise your suggestions please.
Am reading up on the subject and rather like the idea of repairing myself, if I can and if it's wise and not too complex (all thoughts appreciated).
And all of this is in Tauranga!
 
Looking forward to hearing from you.
 
Ross
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It would probably help people to offer suggestions if you explain what sort of motor your boat has.

High oil pressure at normal temperature isn't a good look. Changing oil and filter is the best first step.

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1 - haemorrhage?

 

did the oil leave the engine or stay inside?

 

if all still inside i guess you'd suspect the oil pump

 

2 - engine is new to you or new? what make size and year is it?

 

3 - a blocked oil filter would presumably show a higher than normal pressure, until the internal spring bypass was forced open?

 

4 - an oil filter with a too big thread would simply blow off and be sitting in the bilge with the oil 

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High oil pressure is pretty unusual.

 

Most boat's don't have oil pressure gauges, just warning lights and alarms. Are you SURE it's the oil pressure gauge you are looking at, not temp? (sorry if that's a stupid question!)

 

LOW oil pressure can lead to high running temps, then complete loss of oil pressure, then engine seizing if you don't stop.

 

LOW oil pressure is commonly caused by lack of oil, worn out oil pump, worn out bearings. 

 

I've never seen an engine run overly high oil pressure, but if that is the case I'd expect a stuck oil pressure relief valve, some sort of obstruction in the filter (wrong filter??) or the oil galleries. Provided the oil is in reasonable condition, and not like tar - ie still fluid.

 

As above - what is the engine - petrol, diesel, inboard, outboard etc, make and model would be good. Is their still oil in it??

 

Oh, and what is your idea of normal oil pressure? Common is anything above about 70psi at running speeds, and about 10 psi at idle. But you have to be able to check your engine specs to be sure. It is normal to see this pressure fluctuate with (low) engine speed.

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My oil pressure alarm came on recently.

When I looked in the drip tray all the oil had left the engine and was sitting underneath it. 

Caused by a corroded oil pipe. Replaced with new. All good now.

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The trouble with the oil pressure alarm is that it is set to go off when the oil pressure drops below normal pressure at IDLE. As this is not sufficient pressure for high speed running, if it goes off when the engine is at cruising speeds, the engine can be already substantially damaged!! A gauge is better, (but you NEED the alarm as well), but then you must look at it, and be familiar with what the normal readings are, so you can see if there are any abnormalities BEFORE any damage occurs...

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High pressure may be due to various causes. operating temperature not reached. wrong viscosity of oil,.blockage in oil filter or galleys

The starting pointe might be to change the oil and filter always a good idea on a new boat.

The curious part is the comment that the pressure fell to zero when the alarm went off.

That suggests either major oil loss, major blockage, pump failure or sensor failure.

While you mention haemorrhage there is no indication you mean that literally as it would be evident.

After changing the oil and filter what is happening then will become clearer and eliminate most possibilities.

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Hello and thank you all.

Much appreciated advise.

I didn't think engine details where significant to the scenario: but..is a Bukh 36ME, c1970's. Very happy with it. Oil was in the sump tray, outside the engine. Am quite sure its a gauge, with alarm and light, and the pressure went to zero because the oil had dumped (no oil, no pressure). 

Refilled with new oil and filter and it happened again. 

Got in Dennis of Dennis Marine Diesel  in Tauranga, nice bloke, and he discovered that Elly was bang on the money...pin holes in the feeder pipes to and from the oil cooler. New parts from The Engine Room on their way. Won't need the oil sucker off SF 'cos the Bukh seems to come with its own one attached to the engine (tho there seems to be no pressure with it to make it work!) but want the crimps, and electrical wire crimps if you have them too. Just added VSR and two 6v batteries, looking forward to longevity, wanna change to LED's, and need a cd stereo. All good and happy. Need to connect the solar panel. Not sure about the gas driven refrigerator.

 

Am quite sure that there will be no lasting damage, I turned if off pdq.

 

Thanks again everyone, am very happy knowing you're all out there and are happy to discuss.

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If you had Oil, the engine should be OK. But yes, that problem of Oil light coming on can indeed be caused by very dirty Oil. You may want to put an Engine flush through sometime. Make sure you are using a Diesel Oil if it's a Diesel. All the various Brands of Diesel engine Oils are good oils these days. Many older engines used a straight Mono 30. You won't get a Mono 30 from Supercheap or Repco and often can't get it in less than 20ltrs. A 20/40 will usually suffice. But don't get an oil with too wide a range of that number. The engine will start using Oil excessivley

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when light first came on i checked oil and it was down,topped up to slightly over filled so next best thing was (unsure of last change)so did oil/filter change,older 2 cylinder 16hp yanmar,not using any oil to speak off or leaking

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the 'oil light' is usually the oil pressure light

 

used be a motorcycle courier with an old boxer bmw, with worn bores/rings 

 

it burned a bit of oil and i could tell when the oil was about minimum level as hard braking made the 'oil light' come on

 

hard braking

-sent what was left of the oil to the front of the sump

-which meant the oil pick-up at the back of the sump sucked air

-de-pressursing the lube system

-so the simple diaphragm? switch in the oil pressure switch closed

-which turned the dash light on

 

note quite the same dynamics on a boat but the flow chart should be about the same

 

was there enough oil?

was the oil in good condition?, (not thick mayonnaise due to undiagnosed water leak)

did the oil get picked up (screen not blocked, pickup still attached)

has the oil filter stayed on and tight with no leaks

are the oil galleries clear, (no recent bearing failures)

is the light and sensor wiring good (corrosion, broken conductors, tapping light doesn't cause it to come on)

is the switch working reliably

etc etc etc

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