Oil Pressure Gauge

tmtracey

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I have just upgraded my engine to a Bukh DV24, one of the reconditioned lifeboat engines from Marine Enterprises.

My old engine had a mechanical oil pressure gauge off a tube, but the new one has no such connection.

Would it be okay to not have the gauge? A few people have said that many engines nowadays don't bother with one, though they may be refering to modern engines rather than one potentially 15-20 years old.
 
The vast majority of boats and cars do not have an oil pressure gauge, so it is clearly a "nice to have" rather than a "necessity". However, there will almost certainly be a tapping where the an oil pressure sender is installed to operate a low oil pressure warning light on the dashboard. You could have a proper gauge sender installed in the tapping and connected to a gauge which would need to be sited somewhere convenient.

Richard
 
There is no pressing reason to have one but they are nice to have. Few engines seem to come with them. However, your new engine will have a pressure switch screwed into the block. You can insert a T instead, with the switch on one leg and your old analogue gauge on the other, which would be the ideal arrangement. ASAP do the T adaptors but you may need to check thread size before buying.
 
Great, thanks all. I think I'll keep the oil gauge, nice to be informed what's going on under the bonnet. I've just bought a 1/8 npt tee which should do it, plus a bsp adapter.

I did buy an oil switch on ebay listed as being suitable for Bukh, but the thread was wrong (M10). The real thread for the Bukh being Npt 1/8. Hopefully useful if anyone else goes down this route.
 
My DV20 has an oil light on the control panel - it comes on when the engine is idling which is comforting in a way, because at least you know the light is working!
 
My DV20 has an oil light on the control panel - it comes on when the engine is idling which is comforting in a way, because at least you know the light is working!

It may be comforting for you to know that the light works, but the sender is probably set at about 12 psi meaning that your oil pressure even above idle speed is likely to be on the low side.
 
I don't have the manual to hand, but another thread here quotes 28 to 50 psi oil pressure range for the DV10, with the alarm (light) set to 14 psi. It's likely these figures apply to the DV20, and DV24, too. I'm not going to disturb my engine now, it's all wrapped up for the winter, but I have a small oil pressure gauge and will test next season. The engine had a head recon, new rings and big end shells about ten years ago.
 
I don't have the manual to hand, but another thread here quotes 28 to 50 psi oil pressure range for the DV10, with the alarm (light) set to 14 psi. It's likely these figures apply to the DV20, and DV24, too. I'm not going to disturb my engine now, it's all wrapped up for the winter, but I have a small oil pressure gauge and will test next season. The engine had a head recon, new rings and big end shells about ten years ago.
What is the viscosity of the oil that you are using 15w40?
Please no thread drift onto oil specification ?
 
I don't have the manual to hand, but another thread here quotes 28 to 50 psi oil pressure range for the DV10, with the alarm (light) set to 14 psi. It's likely these figures apply to the DV20, and DV24, too. I'm not going to disturb my engine now, it's all wrapped up for the winter, but I have a small oil pressure gauge and will test next season. The engine had a head recon, new rings and big end shells about ten years ago.

FYI, my boat is fitted with a DV20, as far as I am aware the original, so from 1975, though this year I swapped the head and rest of the top end from a later engine, there was a slight variation in the vacuum valve that sits in the rocker area.

Anyhoo... the engine is likely quite well (ahem) run in at this stage, and oil pressure at idle is 20 psi, and under normal rev range is about 30 psi, so on the lower end of where I would like it to be.

There is an adjustable oil pressure valve down at the filter area. I may give that a tweak to see if it improves things, but I have my doubts. It is a small spring with a ball at the end of it. Adjusting the length of the spring increases or decreases the amount of flow allowed through. Certainly a good idea to screw in a diagnostic oil pressure gauge if you have one available just to check the reality.
 
FYI, my boat is fitted with a DV20, as far as I am aware the original, so from 1975, though this year I swapped the head and rest of the top end from a later engine, there was a slight variation in the vacuum valve that sits in the rocker area.

Anyhoo... the engine is likely quite well (ahem) run in at this stage, and oil pressure at idle is 20 psi, and under normal rev range is about 30 psi, so on the lower end of where I would like it to be.

There is an adjustable oil pressure valve down at the filter area. I may give that a tweak to see if it improves things, but I have my doubts. It is a small spring with a ball at the end of it. Adjusting the length of the spring increases or decreases the amount of flow allowed through. Certainly a good idea to screw in a diagnostic oil pressure gauge if you have one available just to check the reality.

The valve you are discussing is the gallery pressure relief valve. Unfortunately increasing the spring length will not improve your oil pressure (unless the spring is knackered). When the engine is new and the oil cold it is likely to open to relieve the pressure on the pump but does very little after that.
 
The valve you are discussing is the gallery pressure relief valve. Unfortunately increasing the spring length will not improve your oil pressure (unless the spring is knackered). When the engine is new and the oil cold it is likely to open to relieve the pressure on the pump but does very little after that.

It's worth checking that valve.
I once completely stripped a BSA bike engine, replaced the worn shells and main bearing bush, only to find still next to no oil pressure. Changed the pressure relief bits for those from another engine and all was good (by amateur BSA standards). Obviously it leaked more though!
 
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