B6100, D650 engine hot oil pressure question

[motorhead]

At 1800 rpm, at 175 degrees of coolant temperature, my oil pressure is 30-35 psi. Is this a normal oil pressure? I have DELO 1300 15/40 oil in the engine. 2100 hours on the engine. Thanks.

 

[GeoHorn]

This requires some more info.. How many hours on the engine.?.. and how accurate is your pressure gauge.? but it seems about correct as for oil pressure. Lot’s more pressure doesn’t do any more good. I have engines that do 30-35….and engines that do 50-60… ….. and one that when hot..idles at 10… It’s all good IMO.

 

[85Hokie]

At 1800 rpm, at 175 degrees of coolant temperature, my oil pressure is 30-35 psi. Is this a normal oil pressure? I have DELO 1300 15/40 oil in the engine. 2100 hours on the engine. Thanks.

Yes - that is pretty typical.

Answer the following:

COLD - at idle, what does it read? 50+ psi

After working hard, as in the coolant is closer to 210 and after an hour of work, what is the PSI at lowest idle - I would imagine it is under 20 - which is still fine.

I think everything is fine.

In your neck of the woods - that oil is spot on too.

 

[motorhead]

The D650 is on an Onan generator. It starts cold and runs up to 1800 rpm. I found out here, on this site, what the engine was used on in an equivalent tractor. The oil pressure seems the same hot or cold. I have a new oil pressure sender and gauge. The injection pump is locked and sealed at a no-load setting of 1860 rpm. I was thinking of running a 5/40 full synthetic so the oil is thinner at cold start up.
Onan has a safety where the fuel pull doesn't engage until there is about 9-10 PSI of oil pressure.
GeoHorn, the hours are 2108. I put the hours in the original posting. Thanks

 

[85Hokie]

IF you are starting in weather below freezing then the move to 5w-40 may be warranted - but the PSI will drop a bit once it gets real hot - not that the little bit it drops will be much.

You are using a synthetic blend - moving to a lower viscosity will not change much, again IN cold - that is where friction is at it's highest is the only place it will help.

 

[TheOldHokie]

At 1800 rpm, at 175 degrees of coolant temperature, my oil pressure is 30-35 psi. Is this a normal oil pressure? I have DELO 1300 15/40 oil in the engine. 2100 hours on the engine. Thanks.

Normal is a setting on a clothes dryer

Different engines have different oil pressure requirements. Some of the reasons adequate oil pressure is needed are:

1. Deliver oil to the main and rod journal bearings. As long as there is sufficient volume to keep the bearings filled pressure does not matter a wit.
2. Deliver oil to moving parts in the upper end. Since some of that lubrication is done with spray both volune and pressure are important. If pressure is too low the spray wont reach the destination.
3. Provide hydraulic power for actuators. Much more common in engines that employ sophisticated designs like variable valve timing but sometmes used for hydraulic belt and chain tensioners.

Off the top of my head I would expect factory pressure in your engine to be 10-20 PSI higher than you are seing. Oil pressure drops over time as engine parts wear and oil clearances (primarily the journal bearings) increase. I think your pressure probably indicates theres some engine wear but its not scary low and at 2100 hours nothing unusual

JMO,

Dan

 

[motorhead]

Normal is a setting on a clothes dryer

Different engines have different oil ptessure needs. Some of then reasons adequatex oil pressure is needed are:

1. Deliver oil to the main and rod journal bearings. As long as there is sufficient volume to keep the bearings filled pressure does not matter a wit.
2. Deliver oil to moving parts in the upper end. Since some of that lubrication is done with spray both volune and pressure are important. If pressure is too low the spray wont reach the destination.
3. Provide hydraulic power for actuators. Much more common in engines that employ sophisticated designs like variable valve timing but sometmes used for hydraulic belt and chain tensioners.

Off the top of my head I would expect factory pressure in your engine to be 10-20 PSI higher than you are seing. Oil pressure drops over time as engine parts wear and oil clearances (primarily the journal bearings) increase. I think your pressure probably indicates theres some engine wear but its not scary low and at 2100 hours nothing unusual

JMO,

Dan

I figured that because it didn't vary much between hot and cold oil temperature, the oil pump pressure relief was bypassing extra pressure when the oil was cold.
I like your saying, "Normal is a setting on a clothes dryer "

 

[TheOldHokie]

I like your saying, "Normal is a setting on a clothes dryer "

I cant take credit for that. Its a running joke in AA (and similar) self help meetings.

Dan

 

[motorhead]

I cant take credit for that. Its a running joke in AA (and similar) self help meetings.

Dan

19 years and counting......

 

[North Idaho Wolfman]

Simple anwer, your oil pressure is good and within spec.
And any changes in oil weight is going to make minimal overall change.
What you want to do if your worried about hard winter starts, is put a block heater in it and run that off of a high amperage thermocube to turn it on when it's cold enough to really need it.

 

[motorhead]

Simple anwer, your oil pressure is good and within spec.
And any changes in oil weight is going to make minimal overall change.
What you want to do if your worried about hard winter starts, is put a block heater in it and run that off of a high amperage thermocube to turn it on when it's cold enough to really need it.

We don't see extended cold weather below freezing here just inland from the coast. Thanks!