Thread: Suspect oil pump

If the Fault was the oil pump . then it would do it all the time . Perhaps you have a pickup/suction problem . You havent stated whether the oil pressure actually changed whilst going up these hills .No oil pressure gauge fitted perhaps ? Off course the oil level wass good and no big leaks anywhere ? You need to fit a guage and monitor the pressure to understand whats going on.
PS you havent just nipped up the sump bolts lately have you ? What this does is cut off the sump gasket and jam it in in the pickup .

The oil pressure guage doesn't read accurate, just goes to the maximum setting as soon as the ignition turns on. the oil levels fine changed the oil and filter a few weeks ago with shell high milage oil and checked it as soon as it started to make the sound. havent tightened the sump bolts lately, will chase up the fault with the pressure guage though.

Oil pressure guage goes to flat out does it ? how long has it being doing that ? I guess you might have the last of the early instrument binnacles , the later ones have a Tacho in them. Do you have the 4 gauges above the air-con ? IF so you probably have a oil TEMP gauge , posssibly a volt gauge, the oil pressure gauge and maybe a clock (which should be replaced with a Vac gauge).That means is likely that you have 3 senders on the oil pump , the temp gauge the pressure gauge and the idiot light in the binnacle. By swapping them around and earthing the leads out you can tell whats going on .
Still regardless of what they are doing they wont cause the "horrible rattling noise" that appears going up hill and disappears on the flat , although the will warn you of impending doom .
How do you tell that the noise comes from the "front" of the motor whilst climbing up hills , versus the middle or rear or left bank or right bank ? interesting !
Its hard to find a possible fault with oil pump that theoretically can only occur when going up hills. However it could happen for reasons that are connected to starving the pump of oil when at this angle.
The pickup is partially blocked , its cracked , its loose , or the good old standard one of getting a bash in the sump flattening it out onto the pickup.
Ive seen this occur only with a badly sludged engine where the oil return path was blocked and oil simply wasnt returning to the sump quick enough .
The only other thing I think of is that your getting a **** load of detonation when heavily loaded going uphill at lower RPMS.

What about the red light ? AFAIK even with a gauge they still had an oil pressure light.
Does it go on when you turn on the ignition, then go off as you start?
Does it then come on when going up said steep hills?
If not , then there is nothing wrong with the oil pump.

You haven't said so but I used to have a weird problem with an oil cooler with thermostat fitted to my 77. When I started in the morning the cooler would be empty, and if I climbed a very steep hill straight away I would lose oil pressure as the thermostat opened to fill the cooler.
The red light would come on for about 2 seconds, thats how I knew.
Regards Philip A

Yep i've got the old type instrument panel with the three guages and the clock. the sumps intact hasn't had a whack possibly sludged up though i do change the oil pretty regularly although it has very high milage. i thought it might be getting starved of oil at the high angle because after idling for a few minutes on the flat it would settle down. dont think its my timing but ill check that with my timing light. the annoying thing is i cant get it to reproduce the fault at home. and the rattle at the front of the motor was my best guess.

The oil low pressure light doesn't come on only as you say when you start it and then shuts off and i don't have an oil cooler. ah well still scratching the head

OK here is my bet.
If your engine mounts have collapsed, the fan will hit the shroud under load.

Maybe the engine is twisting from the torque and the fan touches.
Have alook at the front mounts and if there is a crack between the top or bottom plate of the mount and the rubber then they have failed and the engine just drops over time.
Regards Philip A

I think you've hit the nail on the head there mate, have just been havin a play under the bonnet and noticed that the front r/h engine mount is missing nearly half the rubber out of it!