Oil Psi question

[Cast-A-Way]

I have read some old posts and a little confused ?

I did an oil change on my 1988 4.3 OMC this weekend then went out for the first run and was reading about 50psi at idle ~800rpm and 80psi at ~4500

It supposedly has less than 40 hours since it's rebuild according to previous owner

Is this normal ?

Aside from the sender or the gauge does it mean not enough oil or too much
I am worried I can't get an accurate reading from the dipstick as it rubs the tube on the way out !

Also what is the best type of oil to use in these engine in regards to thickness ?

Thank you

 

[Cast-A-Way]

Re: Oil Psi question Does this make sense ?

Re: Oil Psi question Does this make sense ?

Found More info in the Forums
I used 10w30 instead of SAE30
So I think it is the wrong viscosity for it
Would it make that much of a difference ?
I will do another oil/filter change and see what happens !

 

[jaxnjil]

Re: Oil Psi question Does this make sense ?

Re: Oil Psi question Does this make sense ?

cast; if your just a little confused then your way ahead of me.
my question is what was your psi before you changed? or was this the first time you ran it?
your pressures sound high to me. if he rebuilt it, it hard to say what he put in there for a oil pump. there is spring loaded relieve valve on the pump that sets the max oil psi and some high volume racing type pumps run a little higher psi. if you can, you need to stick a mechanical gauge on it and double check you gauge.

 

[Cast-A-Way]

Re: Oil Psi question

Thanks for the reply guy's
it was indeed the first time I ran the boat as I have just moved out of the
"resto" phase of it

But I think is was something like 20-30psi at idle
The hard thing is when I try to check the levels the dipstick tube is really hard to get in and out of so I feel that I am not getting an accurate reading.

the boat ran fine all day but I did not really go above 3500 too much !!

 

[Alumarine]

Re: Oil Psi question

Just remember - oil pressure is not an indication of how much oil you have in the crankcase.

Just because you have good pressure doesn't mean you have enough oil.

 

[Gary H NC]

Re: Oil Psi question

Not unusual readings on a fresh engine..
Change it to straight 30 weight and keep running it...

 

[Cast-A-Way]

Re: Oil Psi question

Thank you for the reply's

I checked last night and I did use the wrong type !
I will change it this weekend and let you know

Since it's hard for me to get an accurate reading from the dipstick

Is it safe to say with a filter replacement I need about 4.5 liters if fully drained ?

 

[Commissionpoint]

Re: Oil Psi question

There is no reason that you can't get an accurate reading from the stick. If it rubs the tube thats ok, its not like there is a squeege in there removing the oil from the stick on you. Even if it rubs the stick a lot you can still determine the level in the crankcase accurately. Read the stick as you fill it with oil and you will be able to see where its at.