Yanmar 1gm low oil pressure warning

[abcnuzeman]

So, motoring to my slip after launch, the warning buzzer on my CD25 Yanmar 1GM diesel went off, and the second light from the right on the engine panel lit up. Opening the engine cover, the oil pressure gauge installed by the po showed only 15 to 20 psi and when I checked the dip stick, no oil at all was indicated. Today I sucked what little oil I could out of the engine dip stick tube and replaced it with just over a litre of new oil. After starting the engine, I got almost 50 psi on the oil gauge and thought all was peachy. Five minutes later, the same warning buzzer and light. Any suggestions an untutored amateur garage mechanic such as myself might try next, or do I bite the bullet and throw money at it?

David Owens

[Bruce Ebling]

I had a similar problem with my 1GM. After replacing the oil pressure switch and much head scratching I located the main ground connection that was attached to the engine block. The connection had loosened but was still attached. After soldering on a new ground ring and cleaning the areas around the ring everything worked so much better. Bad grounds can cause all kinds of problems!
Bruce Ebling

[Oswego John]

Dave,

The last thing that you want to do is throw money (boat units) around. I agree with what Bruce told you. Try the easy fixes first.

Some times when you have a poor engine ground, it manifests itself with a poor, or erratic, starting motor.

When an engine has high hours running time, through normal wear and especially cold, dry, starting after long periods of rest, it loosens up and the tolerances become sloppy.This allows blowby in which fuel thins out the lubricating oil.

I would advise a compression check. I don't know what viscosity oil you added, but using a step or two heavier oil just might help the problem.

This problem has come up many times before. Some owners swear by the addition of oil additives, others swear at them. I'm one of the "swear by" guys. With newer engines I have often added Marvel Mystery Oil to the fuel.

With worn engines, I have seen Lucas Oil Stabilizer work wonders on tired motors. It's a personal choice. There are dozens of companies on the market who all swear that their product is the very best. Well, maybe so. Lucas products work okay for me.

I buy one quart bottle at a time at any auto supply store for under $10.00 and save shipping costs.

I hope that the solution to your oil pressure problem is a simple one.

Good luck,
O J

Keep scrolling down.

http://lucasoil.hodgsoncorp.com/lucas_o ... ilizer.htm

[Kevin Kaldenbach]

I don't know how much oil the 1GM holds, but if you ran it dry and the oil light came on, and now you have low oil psi even with oil in it you might have a big problem. You can buy a cheep mechanical gauge from an auto parts store and check your pressure that way. If you do in fact have low oil pressure I would fix the problem right away. This would also be a good time to drain the oil using the plug in the pan to observe for metal filings. or discoloration of the oil to determine what is worn out, pump or bearings.

[Bob L]

On my 27 the audio warning sounded for low oil pressure. Measuring the dipstick, I saw that I had oil. After much thinking about things, I removed the oil pressure detector and cleaned it out. There was a lot of muck in it. After refitting it, I never had that problem again.

Bob

[abcnuzeman]

Thanks to all for the suggestions...I pulled the sender and cleaned it, replaced the oil filter and still get the warnings. I've order a replacement sender unit but I'm not optimistic that this will solve it. Tomorrow I will suck out the oil again...Geeze I hate that. It's such a mess. I'll replace with a non-synthetic 30W Diesel instead of the 10w-30 I used last week in hopes this will help. The oil lamp and buzzer don't go off until the engine has warmed up for 5 minutes or so but I'm not sure what that tells me. Is the oil getting too thin. Anyway, it was another day not being able to leave the slip. This is depressing.
David Owens

[barfwinkle]

Some times when you have a poor engine ground, it manifests itself with a poor, or erratic, starting motor.

Is anything else (electrically speaking) acting up? I lost the engine ground on Rhapsody once and I could not believe what it did to a whole bunch of stuff! Lights, radios, you name it..... The marina owner at the time stated that he hated trying to track down DC "faults" because it was so difficult!

Anyway just a thought.....

Fair winds and gud luck.

[abcnuzeman]

Sorry...I wasn't clear...I did check the ground and haven't experienced other electrical mal-functions, so unless it's the sender it self or just to low a viscosity of oil, I am at a loss and will have to consult a professional...not that I begrudge a craftsman his pay, but since I bought the boat in March, I've yet to unfurl a sail while casting off lots of money...not that my wife didn't warn me, but that's another story. Anybody no a good diesel mechanic in Brooklyn?

David Owens

[Ray Garcia]

Don't fret yet. I was in the same situation as yourself. Last year I pulled the sender, cleaned it out and put it back. Motored just about the whole way to Block Island without a hitch. One week later the damn siren would not go off. Cleaned it again and again. This spring I bought a new oil pressure sender, installed it. Problem solved!

[abcnuzeman]

Well, this may be premature, but I think I've solved my low oil pressure warning issue. What I thought was a parallel issue, low volume of cooling water from the exhause may in fact be the problem. I consulted a Yanmar dealer who suggested the cooling water hoses might be clogged. I removed them and they all had significant blockage and the thermostat was corroded and probably non functioning. I re-assembled everything and ta-da...lots of water from the exhause and the engine ran about 30 minutes before the warning buzzer and light alarms went off...that I suspect will be fixed when I replace the thermostat this weekend. Thanks to all for your suggestions and encouragement to keep at it. I feel I'm making my first tentative steps to understanding my new boat and the skills required to be called a sailor.
David Owens

[Lou Ostendorff]

David;
The previous posts seem helpful, but the real problem you need to resolve immediately is where all your oil is going. You must have a leak somewhere that must be fixed before you can continue to use the engine without destroying it. I have a Yanmar 1GM10 that has survived several oil leaks from rusty pipes, not because I was particularly diligent about watching after it, but because the leaks occured when I was very close to the slip, or already in it. Either of these leaks could have been catastrophic, had I been motoring at full speed, and in a blissful sailing state as can sometimes occur! As it happened, I was able to make required repairs, refill the crankcase with oil, and continue on with no apparent damage at all. I consider myself very lucky, and have since become more attentive to sounds, leaks, and general preventive maintenance.

I will be making a post soon, with pictures, that will chronicle some of my endeavors at engine repair...look out for it.

Good Luck,

[Sea Hunt Video]

I think I want to install an oil pressure gauge with psi readings and a water temp gauge with degrees Fahrenheit readings. Right now all I have is an oil pressure warning light and a water temp warning light both on the Yanmar engine panel.

The engine is a 1982 1GM Yanmar.

What brands, models of gauges are recommended

What installation location(s) are recommended

My first thought is to install them both on the cockpit side of the port side cabin bulkhead. This is where I currently have the DMI knot meter and DMI depth meter.

[rtbates]

I certainly hope you mean 1 QUART...not 1 liter