Low oil supply to 300TDI rockers

My defender has been off the road for ages now, mainly due to what i think is clutch fork failure and finding time to fix. But I have been trying to solve for some time a noisy top end and what seems like a low amount of oil coming out of the rockers. I did some searching and got a few ideas, but couldn't find a thread directly addressing this.

History of the engine is that it was working fined until a hose got a leak and i missed it and overheated. I am at a point now where i have fitted a brand new head with new rockers, cam followers, pushrods, caps etc etc. After overheating i replaced a head gasket (elring) first and that was the first time i noticed it was noisy. It ran for a few thousand km and then started to leak water so I then replaced everything, expecting to fix it. Still a bit noisy and in trying to chase it I noticed not much oil in the top end.

I can't imagine overheating (didn't get that hot) would have caused the longer term problem. My logic is telling me that maybe both gaskets were not the best fit and maybe restricting oil flow. Then tonight i looked at the old head and it looks like the diagonal oil gallery to the front rocker post has a head bolt going right through the middle of it. That seems odd to me but I suppose if it fills up with oil and then keeps going up to the rocker. Does that sound right?

Somewhere i read about putting a wire down the gallery, but you would have to pull a head bolt to be able to do that. I don't really want to pull my brand new head, bolts and gasket if i can help it and wondered if i could get a drill long enough to get down to it and clear if gasket is restricting.

Another item I can check is the pressure relief valve. I have heard that can be a problem if reduced flow to head. I guess the overheating could have encouraged it to stick? I have to check the oil pressure with a gauge, but light not coming on and i suspect it will be ok. So it could be oil pump, but I am trying to look for things that could have been impacted by the overheating.

Any suggestions welcome

As a funny aside, after sitting for more than a year, it was time to move it up to the shed to work on. I had parked another not running vehicle near it and I needed to reverse back a bit to a tree so I could drive out. With broken clutch fork I was expecting to put it in reverse and go back on the starter and then tow it out of its spot. I doubt it did a full revolution on the starter before it sprang to life and i was panicing to turn it off before hitting tree. In low range in gear i just turn the key and it instantly springs to life and then off with the key to stop.... who needs a clutch! I was just really impressed how easily it started after all that time.

craigbau said:

My defender has been off the road for ages now, mainly due to what i think is clutch fork failure and finding time to fix. But I have been trying to solve for some time a noisy top end and what seems like a low amount of oil coming out of the rockers. I did some searching and got a few ideas, but couldn't find a thread directly addressing this.

History of the engine is that it was working fined until a hose got a leak and i missed it and overheated. I am at a point now where i have fitted a brand new head with new rockers, cam followers, pushrods, caps etc etc. After overheating i replaced a head gasket (elring) first and that was the first time i noticed it was noisy. It ran for a few thousand km and then started to leak water so I then replaced everything, expecting to fix it. Still a bit noisy and in trying to chase it I noticed not much oil in the top end.

I can't imagine overheating (didn't get that hot) would have caused the longer term problem. My logic is telling me that maybe both gaskets were not the best fit and maybe restricting oil flow. Then tonight i looked at the old head and it looks like the diagonal oil gallery to the front rocker post has a head bolt going right through the middle of it. That seems odd to me but I suppose if it fills up with oil and then keeps going up to the rocker. Does that sound right?

Somewhere i read about putting a wire down the gallery, but you would have to pull a head bolt to be able to do that. I don't really want to pull my brand new head, bolts and gasket if i can help it and wondered if i could get a drill long enough to get down to it and clear if gasket is restricting.

Another item I can check is the pressure relief valve. I have heard that can be a problem if reduced flow to head. I guess the overheating could have encouraged it to stick? I have to check the oil pressure with a gauge, but light not coming on and i suspect it will be ok. So it could be oil pump, but I am trying to look for things that could have been impacted by the overheating.

Any suggestions welcome

As a funny aside, after sitting for more than a year, it was time to move it up to the shed to work on. I had parked another not running vehicle near it and I needed to reverse back a bit to a tree so I could drive out. With broken clutch fork I was expecting to put it in reverse and go back on the starter and then tow it out of its spot. I doubt it did a full revolution on the starter before it sprang to life and i was panicing to turn it off before hitting tree. In low range in gear i just turn the key and it instantly springs to life and then off with the key to stop.... who needs a clutch! I was just really impressed how easily it started after all that time.

Click to expand...

Did you check the oil gallery feed from the block went straight through the gasket? So pattern gaskets have the holes slightly out, I aways check both block and head with any gaskets I’m using,
If you drill down the feed hole how to you proposed to remove the swarth?

Like wise to you I went to start my 200tdi last week after standing for 10 years and first turn of the key and she was running, went into gear and drove, very impressive,

Thankyou - It was long enough ago that I can't remember if i checked the location of hole. I would like to think i would have...... I certainly wouldn't forget to again! Its unfortunate the holes sometimes don't line up and this is not the first time i have read this in my recent research. I'm pretty sure it was an elring gasket, so not just any dodgy supplier. And I would be concerned that it could be that the new head had an error and didn't line up, except it has done the same since overheating with the original head reinstalled and then the new head.

Good point about the swarth. I guess it will only go in one direction and so if i pull the wire to the fuel cut off and turn it over and over with the rocker shaft off, hopefully it pumps it all through. It seems really odd to me though to have an oil gallery with a head bolt going straight through the middle. I guess with one head stud removed I can put a strip of rag down and still turn it over and pump the swarth into there. I don't want to fill the head bolt thread area with oil and risk hydraulic lock affecting tension.

I just don't want to go through the process of pulling the head back off to check the hole and then find it is say a problem with the oil pump.

Thanks for your thoughts,

Have you a video of the noise?
If its defo valve gear related I would be looking at the tappest and their rollers, which again means head off?

That's a good idea. I will see if I can record it tomorrow morning - then i have to go away for a few days, (so not being rude and ungrateful in not replying)

Update from this afternoon - I fitted an oil pressure gauge and it read 50 psi at idle, going up to about 60 with a few revs - so I think that confirms the oil pump is fine. Documenting exactly what i did (and trying to be a bit more methodical in solving this than i have been) - Yesterday I drained the sump, thinking I was going to remove the sump and look at the pressure relief valve. Then thinking about it, I put oil back to check the pressure and give myself more baseline info before checking to see if enough oil getting to the top of the motor. So I guess that will pool a bit of oil in the top end of the motor, pouring all those litres in there.

When i fired it up to check pressure, it sounded very 'knocking' at first, as you would expect, before oil pumped around and pressure up. But it still sounds noisy to me. Its a bit difficult though because I know the 300tdi is not a whisper quiet motor and its the only diesel I have. So then I removed the rocker cover and fired it up again, trying to look where noise was coming from. And like i said, its all new, including the cam followers, pushrods, rocker arms and adjusters etc. I held my finger on the top of rockers one by one etc and I am not confident that is where the noise if from. And there was oil splashing around everywhere. I ran out of time but wondered if i should get a rag and sop up all the oil in the top and then look again to see if it is leaking out between rockers arms etc.

So I am not convinced now that there is not enough oil up there. But I do think there is still a knock. At the time I put the original head back on, and I thought the same knock was there then (that hadn't been before), I showed the car to my cousin that was a very experienced mechanic and he was confident it wasn't a big end. He recalled an incident where a head gasket was just being touched by the edge of a piston (on a side valve Ford) and produced a difficult to find knock. But when I got the new head, there were no signs of any touching on the old gasket.

Also when i had the head off the first time, I noticed No. 4 piston looked a little bit different. Its still standard bore and I noticed there were some marks in the bore. I think it may have seized at some stage but was honed and new piston put back. It doesn't burn oil or blow excessive smoke. My cousin didn't think it was piston slap, but I am thinking maybe that is a possibility. My cousin wasn't that well at that stage and died shortly after, so while i had been mentored by him for 50 yrs and he was always right, he could be forgiven if his judgement was out a bit. If it didn't run so well I would have considered pulling the motor and reboring but thought I would get a few miles out of it yet. If it is piston slap, perhaps increased from the overheating exercise, then i can live with that for now.

And that's what I have been looking for, what has changed after the motor was overheated and there is this increased noise.

Anyway, will see if I am smart enough tomorrow to be able to record it and upload.

Sounds like oil supply to the top of the head is ok.
Is your vac pump knocking?

Its a new vacuum pump that I put in at the same time that I replaced the head gasket, so that timing fits. But i think I swapped the old one back in to check - was years ago now - and I think it was still noisy. I guess i could make up a blanking plate to keep the oil in and start it without it in there. Do you think it is possible that it was a dodgy one from the start? Could I have got the wrong one? Is it common for them to knock? Which part does the knock usually come from? I can put up with the noise as long as I know its not damaging something in the motor. Sorry about all the questions - no harm in asking!

I can't see how to upload a video, so I stuck it on a facebook page and this is the URL (apparently.... I don't know much about such things!)

I'm heading 'out of range' for the next few days, so won't be able to respond until Thursday to any posts.

I have heard a 300 knocking quite badly, so badly I thought the guy had a 200 under the bonnet turned out he had over advanced the inj pump timing!

Injection pump timing was my thought too.

Back again... but funeral to go to so still another day or so from investigating further. Thanks for the ideas.

Can you see any way I could get the timing out by just changing head and vac pump? I will still check and perhaps get injectors tested, but I'm just trying to back up what i am doing with some logic behind how I got to this point. Also that might help others in the future trying to solve a similar problem.

Back again... but funeral to go to so still another day or so from investigating further. Thanks for the ideas.

Can you see any way I could get the timing out by just changing head and vac pump? I will still check and perhaps get injectors tested, but I'm just trying to back up what i am doing with some logic behind how I got to this point. Also that might help others in the future trying to solve a similar problem.

craigbau said:

Back again... but funeral to go to so still another day or so from investigating further. Thanks for the ideas.

Can you see any way I could get the timing out by just changing head and vac pump? I will still check and perhaps get injectors tested, but I'm just trying to back up what i am doing with some logic behind how I got to this point. Also that might help others in the future trying to solve a similar problem.

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No way to effect pump timing doing the jobs you have done.

But it doesnt mean something hasnt moved through wear of part failure in the timing chest, easy to check if pump timing is still okay without major surgery.
Back in the day 300 engines had big problems with shredding/damaging timing belts.

Thanks - yes it has new timing belt not long before the new head and modified parts - the tensioner or a pulley? I can't remember but I think it is supposed to solve that early problem the 300 had. Finally back and will head out now to do some exploring.

Sorry to jump in here but I have just rebuild my TD5 and seem to have the same story, rocker gear looks a bit dry and a hard knock for a couple of seconds when it starts after standing for a while, I put a pressure gauge into the oil pressure switch tapping and read just over 3 bars pressure when cold, but I'm wondering if it reads high because it's not flowing everywhere, where I measured is after the filter and in the main flow of oil.
TD5 has a small none return valve in the head and I wonder about that.

Good news but not sure if it will help you.
I thought about this and one thing seems logical that the lubrication system must be draining down when the engine is not running, then it starts up and in the first seconds while the pump is filling the system bearings are fairly dry and the engine knocks.
Oil filters should have a none return valve in them to avoid this situation.
Mine had a new filter fitted when I filled it after the rebuild, so I went and bought a new filter, fitted it and primed everything by spinning it over with the injector harness disconnect, when the oil light went out I ran the engine, it sounded fine and I looked under the rocker cover and there was some oil.
Came back home today and tried it after it had not run for two days, it fired up and ran without knocking.
Early days yet and may not be relevant to you but may be worth a try, oil filters are not expensive, BUT if you do then splash out on a good one.

craigbau said:

My defender has been off the road for ages now, mainly due to what i think is clutch fork failure and finding time to fix. But I have been trying to solve for some time a noisy top end and what seems like a low amount of oil coming out of the rockers. I did some searching and got a few ideas, but couldn't find a thread directly addressing this.

History of the engine is that it was working fined until a hose got a leak and i missed it and overheated. I am at a point now where i have fitted a brand new head with new rockers, cam followers, pushrods, caps etc etc. After overheating i replaced a head gasket (elring) first and that was the first time i noticed it was noisy. It ran for a few thousand km and then started to leak water so I then replaced everything, expecting to fix it. Still a bit noisy and in trying to chase it I noticed not much oil in the top end.

I can't imagine overheating (didn't get that hot) would have caused the longer term problem. My logic is telling me that maybe both gaskets were not the best fit and maybe restricting oil flow. Then tonight i looked at the old head and it looks like the diagonal oil gallery to the front rocker post has a head bolt going right through the middle of it. That seems odd to me but I suppose if it fills up with oil and then keeps going up to the rocker. Does that sound right?

Somewhere i read about putting a wire down the gallery, but you would have to pull a head bolt to be able to do that. I don't really want to pull my brand new head, bolts and gasket if i can help it and wondered if i could get a drill long enough to get down to it and clear if gasket is restricting.

Another item I can check is the pressure relief valve. I have heard that can be a problem if reduced flow to head. I guess the overheating could have encouraged it to stick? I have to check the oil pressure with a gauge, but light not coming on and i suspect it will be ok. So it could be oil pump, but I am trying to look for things that could have been impacted by the overheating.

Any suggestions welcome

As a funny aside, after sitting for more than a year, it was time to move it up to the shed to work on. I had parked another not running vehicle near it and I needed to reverse back a bit to a tree so I could drive out. With broken clutch fork I was expecting to put it in reverse and go back on the starter and then tow it out of its spot. I doubt it did a full revolution on the starter before it sprang to life and i was panicing to turn it off before hitting tree. In low range in gear i just turn the key and it instantly springs to life and then off with the key to stop.... who needs a clutch! I was just really impressed how easily it started after all that time.

Click to expand...

Any progress on this?

Sorry for the silence - I refresh the window on this page but it seems i have to log out and back in again to see new posts. Could be some sort of settings on my computer.

First I checked the timing of the injection pump and with the flywheel pin in, I couldn't get the injection pump pin in. Tried to put a 9.5mm drill in to the pulley on the pump and wouldn't go but an 9 would. My Haynes manual (that i often find easier to follow) mentions pump locking screw and keeper plate. I can see a screw in the same position on the pump but not the keeper plate. I wonder if that is the 200tdi pump vs my 300 in the manual? So today I had a go and got the 9.5 in but before i loosened anything, with my son helping and socket on the crank pulley nut, the pin went into the flywheel. So I think the timing is actually so close that its not the problem and performance has always been good. I also saw a youtube about using a dial gauge on the pump and should measure 160, but I think I will leave it there for now.

I removed the vac pump, and with a mark on the contact pad I was thinking I had found the problem (see photo).

I taped up the hole in the block (after cleaning up the surface with brake clean so it would stick well) and I didn't think it had changed anything noise wise, but below is another video and now I'm not sure it isn't a bit better. The vac pump is incredibly hard to push the piston in to work it - is that right? I am a bit concerned about the wear on the pump contact pad after only a few thousand kms. And maybe as revs increase and the first video goes quieter, with revs that stiff to operate vac pump is 'floating' a bit in the open position? If it was stiff and hard from new, has caused that mark on the piston/contact pad? It was a britpart vac pump - perhaps false economy being one of the cheaper available items back in the day. When i got the car, some years back, I had it checked out by a specialist that pointed out the old vac pump was working fine but had a bit of an oil leak, and while buying other parts from UK i added this to the order, thinking I would need it one day, Then when i did the head gasket, with the extra space to access I decided to change it, and that coincided with the new noise. More time has passed so have thrown that money away on that new vac pump it would seem - false economy of cheap parts!

Below is another recording, including releasing the pressure on injectors - see what you think and any comments appreciated. So (unless someone comes up with the solution overnight!) tomorrow will be pull the injectors and take them for testing and cleaning. Then off with the sump and remove big ends. I couldn't find my old plastigauge, so will pick up some while out. And while in there I will pull the pressure relief valve/ piston, measure spring etc. And I will test the suggestion about testing when it is on tdc for each cylinder, to lever on the end of valve/rocker to see if movement - ie. is the piston hitting valves. On the old head, the valves are slightly recessed and no signs of any touching of pistons - so i don't think that is the issue - but i am checking everything.

And maybe as revs increase and the first video goes quieter, with revs that stiff to operate vac pump is 'floating' a bit in the open position? If it was stiff and hard from new, has caused that mark on the piston/contact pad? It was a britpart vac pump - perhaps false economy being one of the cheaper available items back in the day. When i got the car, some years back, I had it checked out by a specialist that pointed out the old vac pump was working fine but had a bit of an oil leak, and while buying other parts from UK i added this to the order, thinking I would need it one day, Then when i did the head gasket, with the extra space to access I decided to change it, and that coincided with the new noise. More time has passed so have thrown that money away on that new vac pump it would seem - false economy of cheap parts! I think tomorrow I will continue as planned, do the injectors because who knows when they were last touched, and check bearings etc. Won't take long and crosses a few things off the list for potential future problems.

https://scontent.fmel3-1.fna.fbcdn....=e9749bcc2832b2b08a7ae05c4377b51d&oe=5E18C33E

I'm not very good at this computer etc stuff. Last time I pasted the URL and the video from the facebook page nicely embeded itself. This time I can't seem to repeat what i did. If you click on this link it should go to the page and hopefully you can see it. If your smarter than me and can paste it back in here that would be great.

https://www.facebook.com/groups/270...70837090474012&notif_t=group_comment_mention#

Are there any forensic mechanics out there! I don't think the motor is dead but found a couple of 'skeletons' in the sump. They are not magnetic and at first look like they could be teeth off a fibre gear, except don't seem to have contact surfaces. Anybody know these motors and can suggest where they came from? The small shiny metal bit I can't place either. I tipped the last bit of oil out, filtered through a rag and put a magnet to it, and it looks like this is the only bit of metal. I can bend it with my fingers but it is pretty stiff, but not as stiff as a retaining tag. It doesn't look scuffed or hammered on the surface but the edges have been 'torn' - not ground away. And who knows - this stuff could have been there for years.

I started a new thread because the old one doesn't seem to display the latest video clearly. Update though with sump off is big ends and bearings look good. I think i will shove a new set of bearings in regardless - only a few bolts and retension - will put some engine assembly lube in when fitting. I can't get the oil relief plug out yet. What were they thinking! A plug of that diameter with that much contact surface and they put a shallow slot into brass. I am going to try and grind up a tool so i can make contact with more of the slot. Then I guess i drill it and bash it etc and buy a new one.