Perkins 4/107 oil pressure

Try a search for 'engine oil', there are countless threads that will give you much information. You need an oil with an API C? Rating. The C stands for compression, i.e. diesel, whereas the alternative S stands for spark, i.e. petrol. Check your engine manual for the grade they recommend but, as you will see as a result of your search, in many cases the recommended oil is obsolete and becoming difficult to source. I don't think you told us what engine you have but in many cases the recommendation is API CD, obsolete since about 20 years ago but available if you try hard.

There is also a page on the topic on my website, under Engine.

As a retiree of a major oil company I will answer your last question with the party line, definitely not! A colleague used to test every commercial oil additive available. He never found a single benefit from any of them.

Perky 4107
 
I have two 107's in my boat, the port engine sits at 48psi and the stbd sits at 50psi, this is hot or cold from 700 - 3600 rpm.

I use castrol multiplant or HDX30 engine oil, these engines were designed to use detergent based oil and not the modern multigrade types although it should make no difference, but I would not use any synthetic types.

It sounds as if you have an electrical guage, I would test the pressure with a mechanical one to confirm details.

If you have no oil cooler you will need an oil filter housing with cooler ports to fit one (I have a spare one if you need it), the oil heat exchanger should be fitted to the engine cooling system not the raw intake (oil that is too cold is no good for the engine).

Oil additives are no substitute for a decent oil IMHO, you could try a monograde upto say 50wt.

The important thing with oil pressure is that its constant, I would run it for a while and keep a close eye on the guage.
 
Engine oil and filter changed 8 hours ago, no fuel in oil, I was a nechanic and know from my apprentiship in the 60;s that ford cars ran at 40 psi at speed and 10 on tickover and was hoping this engine being of the same vintage ran similar, so I guess engine has to come out.

Richard
If the gauge is correct, then maybe indicating some wear, either crank bearings or oil pump. Bear in mind that this engine was designed and built when oil was usually 20/50 or straight 30 or 40. I would bet that you have 15/40 in it? This will allow a showing of lower oil pressure than with a higher viscosity oil.
I would check that the guage is correct and if it is then assume some wear, I would run it until a change in pressure signalled more wear before pulling it.
Stu
PS posted without looking at the other posts
 
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interesting way to go, what was your oil presure before and also after the cooler mod and how much dif did oil make. How did you cool the cooler?

Richard

Checked the can and it's 20w/50 that I've got not 10.

Running at normal revs I was getting around 50 to 55 psi. Trouble is that with engine good and hot coming back to idle the low oil pressure switch was 'just' flicking in and out.

The oil cooler is mounted on the forward end of the engine and salt water is drawn through it by the raw water pump. It sits between the seawater strainer and the pump. The cooler is about 350 mm long and 50mm dia. The water passes through a cluster of about 10 heat exchanger tubes in the centre Of the unit with the oil circulating around the outside of the tubes. It's made no difference to the running temp of the engine which is stable at 88 to 92 degrees depending on load.

Oil pressure is now 65 at revs and around 45 at idle
 
Hi mine starts at 40-45 then after an hours running it drops down to 20-25 always has ,i am running on classic oil which is a bit thicker thrown the can away so can not be certain of the grade but think it was 20-50,mine has an oil cooler,but sounds ok,runs ok,no smoke even at start upif it sounds ok at idle then "its ok" mine was fitted in 1976
 
I have looked mine has no oil cooler so maybe that is tyhe fiirst thing, intereresting to hear your pressures similar to mine, mine is 68 motor.

Richard
 
Made a mistake, looked at the service invoice, the grade in the engine is Shell Rimula X TR4 15w 40, not 10w 40, with this being a tad thicker are all the comments about go to a 20w 50 not valid now.
I understood that the figures meant that the first number eg 15w means that is is thinner when cold than a 20w and the second number 40 or 50 denotes how thick it is when hot, both these figures being measured on the redwood viscosity meter, eg 10 means 10 seconds to go through a designated hole , 15 , 15 secs etc, can someone tell me if this is correct.

Richard
 
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