olsver

olsver

Member
My oil pump has failed for a third time.

The first one seemed improbable but this is crazy.

Each time it happens when I start it for the first time after leaving it for a few weeks.

It seems to be the start that is causing the issue.

I replace the pump and all is then ok.

The damaged pumps have very little obvious damage but usually have surprising amounts of wear on the spline.

I remove the bypass valve and that looks normal too.

I have replaced them before but it isn't till I fit a new one that I get pressure back.

I'm worried that I have destroyed this engine because I let it run for 10 minutes before I climbed in to drive and then i noticed the cheery green light of doom.

It is a standard 2.25 diesel. Nothing that isn't an OEM part except for the radiator (couldn't find an original locally) and a high torque starter motor.

The car is regularly maintained. The oil is new but is still the cheap oil I used to check the last pump had fixed the problem. Has gone less that 20km on this pump.

Kept on level ground, more milage, the outside temperature is -15°C.

Any ideas? I've almost lost my mind here.
 
Sorry you’re still having problems with oil pump
I would change supplier if not already done so , and ensure you get a standard pump , the aftermarket ones not as good as original , the other thing to look at is the driving gear on camshaft and the top shaft that engages wit( the oil pump to ensure all splines good condition and engage correctly , I recall the shafts engage a certain way
 
steve2286w said:
Sorry you’re still having problems with oil pump
I would change supplier if not already done so , and ensure you get a standard pump , the aftermarket ones not as good as original , the other thing to look at is the driving gear on camshaft and the top shaft that engages wit( the oil pump to ensure all splines good condition and engage correctly , I recall the shafts engage a certain way
Click to expand...

I think you are right. That gear at the top is worth looking at again. When fitting this pump I actually measured the drive rod to check it meshes with that gear properly. There wasn't much length on the spline that had engagement at the top but enough. There seemed to be more than a cm of vertical movement on the drive rod. That gear on the camshaft looks good. No obvious damage. I stuck a boreascope up to get some photos.
 
Would be worth having a chat with Turner engineering they are good with support and will have the correct quality parts.
Do you have an oil pressure gauge fitted or just relying on the pressure switch?
 
Blackburn said:
Would be worth having a chat with Turner engineering they are good with support and will have the correct quality parts.
Do you have an oil pressure gauge fitted or just relying on the pressure switch?
Click to expand...
I agree. Turner Engineering are a great company and they were excellent with ensuring I had the right parts for my engine rebuild. These last two pumps have come from them and I really don't think that the quality of the pump is the problem. If they are breaking then there must be something else very wrong to cause it.

I have an external, manual pressure gauge which I can attach to the place that the switch is fitted. I've tested the gauge too. I get a zero reading. It isn't just low pressure, it is no pressure.

I've been ruminating on it, as it is way too cold to actually do anything, and I've had three thoughts.

One, maybe it is the place that I'm measuring the pressure. Could something be blocking it? Could that ball and spring valve be broken in some way that blocks it or sticks? Even if I take the pressure gauge off, no oil comes out of that hole. I guess the way to check this is to release the banjo bolt feeding oil to the rockers to see if oil is moving.

Two, maybe I can see of the drive rod for the oil pump is turning by removing the injector pump and looking down on it. If I crank the engine I can see if it is meshing and turning it. If it is, then I'm at a total loss how there can be no pressure.

Three, this one is going to show you what a novice I am, but, is there a problem with where the oil is coming out at the top of the pump. I guess there has to be something stopping the oil just pouring into the camshaft housing and instead redirecting it to the filter. Could I be missing something that means the oil is taking a different path than it is suppose to.

If you notice me sounding crazier and crazier it is because i'm completely baffled by this and am slightly worried that i'm in a Land Rover owner's personalised nightmare.
 
When you do your oil changes do you measure the amount fitted?
Thinking if the dipstick tube has slipped in the olive and oil level is actually low.
Try a piece of stiff fencing wire down dip tube till it hits sump and see what level oil is.
Does pump actually sit in the oil or is it the filter only maybe a crack in between pump and oil level so sucking air
Like you I am clutching at straws there was a chap on here with a six pot having similiar issues and his pump was fitted lower down so blocking outlet port.
 
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EA99699F-CE8F-4BC8-83F0-E486463CB061.png
good point Blackburn ,the previous pumps fitted don’t look correct , the mesh filter should be under the bottom pump casing as above
85F25C38-9B31-409A-BC62-671145CE5FCE.png
 
Last edited:
Blackburn said:
When you do your oil changes do you measure the amount fitted?
Thinking if the dipstick tube has slipped in the olive and oil level is actually low.
Try a piece of stiff fencing wire down dip tube till it hits sump and see what level oil is.
Does pump actually sit in the oil or is it the filter only maybe a crack in between pump and oil level so sucking air
Like you I am clutching at straws there was a chap on here with a six pot having similiar issues and his pump was fitted lower down so blocking outlet port.
Click to expand...

That is really worth a try. I think i put two flasks of oil in, which would be around 8 litres but I couldn't swear to it.

I'll put another few litres in and see. I'll be a laughing stock if this works but I won't mind at all.
 
olsver said:
That is really worth a try. I think i put two flasks of oil in, which would be around 8 litres but I couldn't swear to it.

I'll put another few litres in and see. I'll be a laughing stock if this works but I won't mind at all.
Click to expand...

Is the oil capacity not 6 litres on your engine?...
 
Shippers said:
Is the oil capacity not 6 litres on your engine?...
Click to expand...

It should be but I've checked my shed and it took two 4 litre bottles of Castrol GTx to get it to the right level on the dip stick. There is only a little bit left in the bottle.

I guessed it was an extra litre for the oil filter and one for luck.

This actually might be the cause. It was a Danish military vehicle. If it has a non standard oil pan then maybe it requires a different pump or more oil than the dip stick would suggest.
 
Just a thought: if the problem only occurs after the car has been standing for some time at -15C, the oil must be really thick and viscous under those conditions. I'm not sure what viscosity GTX is (maybe 20W50?). I'm impressed that a diesel Series Landy will start at all at -15C (must be a good battery) but the oil pressure under those conditions must be sky-high - maybe enough to put severe strain on the pump drive mechanism?
 
Agreed, I think the oil is too thick and there may be an issue with the bypass for cold weather. I would be looking at a 5w-30 at those temps and also a sump heater.
 
ExMil109 said:
Just a thought: if the problem only occurs after the car has been standing for some time at -15C, the oil must be really thick and viscous under those conditions. I'm not sure what viscosity GTX is (maybe 20W50?). I'm impressed that a diesel Series Landy will start at all at -15C (must be a good battery) but the oil pressure under those conditions must be sky-high - maybe enough to put severe strain on the pump drive mechanism?
Click to expand...

You are right. I also thought this might be the case but I have been talked out of it by people who tell me how strong the pump design is. I shared some photos of some metal debris from the last pump that had broken off the pump drive shaft spline. The pump still engaged at both ends so I'm not sure how the pump stopped completely as a result of this damage. I suppose debris could be blocking the channel to the filter?

There is no unusual sound when this happens. No bang or clattering. If the drive shaft breaks and or skips in the spline then it is doing it quietly.

The engine starts easily down to -25 due to an enormous battery and a high torque starter motor. It isn't really drivable below that temperature because there is no way to stop ice build up from my breath on the inside of the front windscreen.

I sometimes use an electric engine heater that warms the coolant for an hour if it is really cold but I can't really notice the difference.

I'll order a new pump and try the 5w 30, and only starting after pre heating the engine.

I'm not sure I dare to try starting it again without checking that there is no metal from a broken pump.
 
olsver said:
I also thought this might be the case but I have been talked out of it by people who tell me how strong the pump design is.
Click to expand...
Yes, I'm sure that's true. The LR engine designers must have thought about starting under all kinds of conditions, including low temp, and the 2.25 engine is known as a reliable, long-lasting design. Normally, the pressure release valve would just dump any excess pressure back into the sump. But for the pump to resist enough to shear the drive, surely something must be blocking the outflow from the pump (unless the drive is misaligned)? Maybe some metal bits from the last pump failure?
One other thought: you mentioned it was an ex-military engine - did it have the military oil cooler (not something you would normally need in Norway, but commonly fitted to military engines)? I'm wondering if there could be some special military setup e.g. non-standard oil filter or an oil thermostat? Otherwise, this is a strange one!
 
ExMil109 said:
Yes, I'm sure that's true. The LR engine designers must have thought about starting under all kinds of conditions, including low temp, and the 2.25 engine is known as a reliable, long-lasting design. Normally, the pressure release valve would just dump any excess pressure back into the sump. But for the pump to resist enough to shear the drive, surely something must be blocking the outflow from the pump (unless the drive is misaligned)? Maybe some metal bits from the last pump failure?
One other thought: you mentioned it was an ex-military engine - did it have the military oil cooler (not something you would normally need in Norway, but commonly fitted to military engines)? I'm wondering if there could be some special military setup e.g. non-standard oil filter or an oil thermostat? Otherwise, this is a strange one!
Click to expand...

We've finally had some warmer weather and I pulled out the oil pump. Even at just 5 below the oil was quite thick. I found a small amount of metal in the pump. Two irregular nuggets less than 0.5mm in size. It is likely these dropped into the mechanism when I lifted out the drive shaft as the pump moved freely when turned.

I've cleaned and reassembled it now but want to check where the oil goes next.

I plan to remove the oil filter assembly and ensure that there is nothing blocking the channel between the pump and the filter. I can also check that the place where the pressure gauge is fitted isn't broken.

There was no metal in the oil pan.

Despite running the engine without pressure (apparently) there was still oil in the rocket cover and even some oil in the vacuum hose running from the breather. Is it possible that oil is being pumped to the top of the engine and not running back down to the pan? Would this fill the rocker cover and starve the oil pump of oil?

I attach a photo because I wondered if the missing fragment by the inlet hole (in the base of the chamber at the top) is normal. Could that me something that has come off and blocked the oil feed.

IMG_20210301_202928~2.jpg
 
***FIXED***

Turner Engineering found the problem.

They saw my image of the skew gear posted above and noticed that it is missing the blanking plate. Fantastic after sales support from them.
 
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