Perkins Prima M50 Oil Consumption

[Rocketman]

Hi I just bought a new boat to me, a 40 ft, 1995 Beneteau, that has a Perkins M50 engine, the engine hours are a bit of a mistory, but I believe it to be in excess of 5000 hours. The boat was used in the BVI fleet for 8 years. Since I bought the boat I have put about 75 hours on the engine, it runs great, starts great but uses about a quart of oil every 15 hours. I also have some questions about the fuel I have been using. I have used mostly fuel from a dock or Marine fuel, but I have used auto fuel from a gas station. I was told by a friend that the fuel used for road use does not have enough surfer in it and should not be used in my engine. Any advise from anyone who knows is greatly appreciated.

[Chief Engineer]

Smoke?

[Rocketman]

It does smoke some, a little more when it is cold and warming up, when cruising along at 2000 RPM's I have noticed some light blue smoke. Not knowing the engine I do not know if burning a quart every 15 hours is excesive. Afer reading the owners manual it mentions the air induction system may need to be cleaned, and that the engine temp may be to low. It run's around 165 degrees according to the gauge. I am also wanting to find an engine shop manual so I can check the valve clearances. Any help in that department would also be helpful.

[Mark Zarley]

After warming up the light blue smoke is probably your 1 qt of oil usage. Do the math and figure out the number of eng hrs per year. Divide by 15 and you have your yearly consumption per year in qts. Compare this cost to a possible rebuild as people renting a boat for a week or two aren't as kind to the mechanicals as an owner would be. Keep an eye on your crankcase pressure, an increase indicates ring blow by (most probable cause of smoke is worn rings) with imment faliure to follow. Getting the manuals is a great idea and will help you to become more informed.

[neilpride]

No oil in the bilge , or any trace of a big leak around?
Blue smoke in hot mean to me worn rings, valve seals, plus a quart every 15 hours is to much for me.

You check if there is any trace of oil in the air filter coming from the breather?
And what kind of oil ? 15W40? sometimes swichting to a mono 40w stop a bit the oil burning.
Cheers.

[Rocketman]

No oil leaks that I can find, the bilge is clean, I am using straight weight 30 oil. I also feel that 1 quart every 15 hours is to much, but I do not know if it justifies replacement yet concidering that seems to be the only concern at least for the moment. Does anyone know the procedure and clearances for the valves on this engine or were to get that information?

[Chief Engineer]

Google it.

If you are not adept at adjusting valves.....let another mechanic do it for you.

[Rocketman]

Thanks for the advise to all, I have tried to get a Mechanic in our area to look at my engine, and evaluate it, but good diesel mechanic's in this area are not very responsive, I have left messages for 3 so far, over the past week, and none have responded.

[JusDreaming]

There is a saying concerning "Perkins" "If it isn't leaking oil it doesn't have any"
The English never made watches due to the oil staining your wrist
ANd yes I have two Perkins and yes they do use a bit of oil, but that much seems excessive. I use a pint +/- about every 30 or 40 hrs.

[perchance]

You said 8 years in the BVI fleet. If that means it is an ex charter boat the cylinders are probably glazed due to excess low speed operation from battery charging. That's just a guess on my part.

[Pete7]

Originally Posted by perchance

You said 8 years in the BVI fleet. If that means it is an ex charter boat the cylinders are probably glazed due to excess low speed operation from battery charging. That's just a guess on my part.

Now that is a good point worth considering. We had a similar problem, though not bad enough to burn oil from the previous owner using the engine very gently. Solved it with a high speed dash across the English Channel into the teeth of a gale flat out for 14 hours. Ran like dream for the rest of the season after that.

Pete

[Radek 2222]

Hi guys

Is there anyone who has Perkins M50, My engine harness burn dow Just the ground wires( don't ask how this happened). But anyway I have hard time to wire the 3 relays , The gauges come on when I turn the key but I can't crank up the engine. I replaced the relays new starter and most of the ground wiring coming from sending units temperature,oil pressure. but I can't get it running. The starter won't engage.
I have the repair manual which has wiring diagram there, but the wiring diagram is for old panel with push button starter and I have Cole Hersee Ignition switch.
So the relays are wired differently than as is show in the wiring diagram.I just can figure out. Any advise please.

[deblen]

Service manual https://docs.google.com/viewer?a=v&p...NzdmMzM2NzU1Mg


https://www.cruisersforum.com/forums...al-201913.html


https://www.cruisersforum.com/forums...le-235422.html


Google Perkins Prima 50 manual


Cheers/Len

[a64pilot]

Originally Posted by Pete7

Now that is a good point worth considering. We had a similar problem, though not bad enough to burn oil from the previous owner using the engine very gently. Solved it with a high speed dash across the English Channel into the teeth of a gale flat out for 14 hours. Ran like dream for the rest of the season after that.

Pete

I would run it hard, but also put a detergent additive in the oil, sea foam or marvel mystery oil.
Glazing is essentially a varnish build up over the cross hatching of the cylinders, it occurs on lightly loaded new engines and occurs because the engine doesn’t get cylinder temps high enough to cook off the combustion products.

Running one hard raises the cylinder temps, higher combustion pressure forces the rings harder against the cylinder helping to scrape off deposits, and the detergent additive may help clean them off.

Glazing is a lot like battery sulphation, it can sometimes be reversed

[Compass790]

Don't know about USA diesel but a diesel engine is a diesel engine & would have thought that road fuel would be the same as marine diesel. No difference in NZ.
As for the oil consumption, sounds high to me as well. Give it a WOT blast for 2 hrs & see if it helps. Others in CF have suggested a little Bon Ami in the bores & a hard run, then change the oil. Makes me uneasy but if you are desperate give it a go.
You could also try high mileage oil in a C rating, they have like 40w-70 here or 20w-60