IH 966 Oil Pressure

[Bootheal]

What would cause oil pressure to be delayed being picked-up by the sending unit? Almost positive there is no (or not much) oil pressure being generated by the oil pump for several seconds (10 to 12) immediately after starting. I have convinced myself there is a definite engine noise change when the oil sending unit starts registering pressure.

Is there maybe check valves that should be holding the oil so all the galleries don't need to fill at the same time?

What would you look for first?

New oil and filter change doesn't have a noticable effect on slow pressure build up.

Thanks for any advice you may have to share. Mike

 

[Tinkerer]

I would remove the sending unit and connect a known to be good mechanical pressure gauge to verify it really is slow to build pressure. A clean grease gun hose is a good way to make the connection. If it is slow to build pressure it could be plugged screen on the oil pump pick up tube or a failing pump.

 

[DIYDAVE]

X2 on check the strainer, first...

 

[Junkyard]

A pretty common maintenance item on several models of diesel farmalls were rods/mains and oil pumps. Take a gander at them when you pull the pan to check the pickup. It's most likely one of the things mentioned, or a combo of all.

 

[Tenwheeler]

My 1066 has always done that. The filters are upside down and it takes a bit to get oil pressure. All good points others have made but unless something has changed I would not be concerned. Still running about 35 PSI working when hot?

 

[Bootheal]

Tenwheeler, I'm hoping you are correct as I don't have a place to remove the pan just yet. Getting started on building a machine shed but it's going to be a little and expensive! For some of us it takes awhile to make a small pile and very little time to get rid of it.. Such is life around our house.

 

[Tenwheeler]

I bought my 1066 about 20 years ago. We rebuilt it this year due to liner o-rings leaking coolant into oil. The bearings were dated 1973 and the crank was good. It has always done the engine sound change when oil pressure came up a bit slowly.

 

[Bootheal]

Thanks for the input. I have not checked the serial number to date the 966 but it's probably an early to mid '70 model. Very dependable and hardly little maintenance. Like yours, gad new sleeves several years ago (electrolysis) so ever since the water chemical filter gets replaced once a year. It use to do a lot of heavy lifting, now she and I just putter but I still need her to putter. Last few years she had to be outside all the time. Really taking a toll but hopefully soon will have a shed for her and a friend. Thanks for the information

 

[td25c]

Sometimes it's just the " Nature of the Beast " . My excavator is like that .

When cold there is a delay in oil pressure build with noticeable change in the engine noise after the oil pressure is up .

Probably 4 to 6 seconds delay in my case depending on ambient temperature . It's always been that way .

As suggested thread in a manual gauge in the block oil gally & observe it .

I would be more concerned about comparing oil pressure at idle verses full RPM when at operating temp .

20 psi at idle & 45 at full throttle when she's hot .............. Farm it up with the 966 !