Hi all,
I have a 3.9 RV8 with the intermediate timing cover with crank driven oil pump. I'm seeing good oil pressure of around 40psi at idle, but I'm suspicious about oil flow as I seem to have very little oil arriving at the rockers.
I've not run the engine for more than a few minutes, but all I see is a couple of drops of oil oozing from each of the small notches in the rockers. So the shaft is getting at least some lubrication, but the pushrods and the valve stems and everything else is staying bone dry. Which surely can't be right?
I'm using a remote filter - and I did think that I may have connected it the wrong way round, but tried swapping the connections earlier and it didn't appear to make any difference at all, either to the oil pressure or flow at the rockers. This itself is confusing me as I've read a lot about filters having non return valves - so I would expect to get no flow & pressure at all if connected incorrectly.
I'm also running a modified sump and oil pickup, but I don't think this can be causing the issue as if the pickup was sucking air I'd wouldn't expect to see such a healthy oil pressure.
I've also had the pressure relief value out, but looks and feels fine, with no sign of sticking.
Any thoughts?
Thanks,
Adam
Oil flow (or lack thereof)
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ian.stewart
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My yardstick is twofold:
1. Pressure gauge reading something useful
2. Oil oozing out between rockers & rocker shaft pedestals.
The oil certainly doesn't spray out, you can run the engine at idle with the rocker covers off, and it won't make a mess.
As soon as oil is running down the valley it will run off onto the camshaft and crankshaft and get sprayed everywhere.
Chris.
1. Pressure gauge reading something useful
2. Oil oozing out between rockers & rocker shaft pedestals.
The oil certainly doesn't spray out, you can run the engine at idle with the rocker covers off, and it won't make a mess.
As soon as oil is running down the valley it will run off onto the camshaft and crankshaft and get sprayed everywhere.
Chris.
--
Series IIA 4.6 V8
R/R P38 4.6 V8
R/R L405 4.4 SDV8
Series IIA 4.6 V8
R/R P38 4.6 V8
R/R L405 4.4 SDV8
Thanks for replies so far...
Spend: The longest I've run it as prob about 5 mins at a fast idle. But I'd expect the rocker shaft to fill up in much less than that?
Chris: I have pressure (verified by mech gauge and the warning light), and do have a small amount of oil at the rockers - but certainly not a continuous flow enough to run down the pushrod bores into the valley.
I'm getting more convinced that something is wrong, but less sure about what could be causing it!
Spend: The longest I've run it as prob about 5 mins at a fast idle. But I'd expect the rocker shaft to fill up in much less than that?
Chris: I have pressure (verified by mech gauge and the warning light), and do have a small amount of oil at the rockers - but certainly not a continuous flow enough to run down the pushrod bores into the valley.
I'm getting more convinced that something is wrong, but less sure about what could be causing it!
If you remove a rocker shaft and then crank the engine, the oil will fire out of the hole at a tremendous rate, and make a proper mess.
Not scientific, but gives an idea that oil is indeed flowing.
Also, be careful about the oil pressure reading:
I plumbed in a remote filter head with filter (non return valve type), and got the hoses back to front. The pressure gauge read very well, but the oil wasn't circulating, it was being dumped back into the sump. Rebuild required.......
So you are right to be cautious.
Trouble with the intermediate cover is you can't spin the pump without turning the engine over.....
If you pop out a couple of tappets, you should get oil flooding out there, and they are in the main galley supplying the rest of the engine.
Chris.
Not scientific, but gives an idea that oil is indeed flowing.
Also, be careful about the oil pressure reading:
I plumbed in a remote filter head with filter (non return valve type), and got the hoses back to front. The pressure gauge read very well, but the oil wasn't circulating, it was being dumped back into the sump. Rebuild required.......
So you are right to be cautious.
Trouble with the intermediate cover is you can't spin the pump without turning the engine over.....
If you pop out a couple of tappets, you should get oil flooding out there, and they are in the main galley supplying the rest of the engine.
Chris.
--
Series IIA 4.6 V8
R/R P38 4.6 V8
R/R L405 4.4 SDV8
Series IIA 4.6 V8
R/R P38 4.6 V8
R/R L405 4.4 SDV8
ChrisJC wrote:If you remove a rocker shaft and then crank the engine, the oil will fire out of the hole at a tremendous rate, and make a proper mess.
Not scientific, but gives an idea that oil is indeed flowing.
Also, be careful about the oil pressure reading:
I plumbed in a remote filter head with filter (non return valve type), and got the hoses back to front. The pressure gauge read very well, but the oil wasn't circulating, it was being dumped back into the sump. Rebuild required.......
So you are right to be cautious.
Trouble with the intermediate cover is you can't spin the pump without turning the engine over.....
If you pop out a couple of tappets, you should get oil flooding out there, and they are in the main galley supplying the rest of the engine.
Chris.
That's a good idea.
You could take all the spark plugs out to so that if any cylinder happened to be on the start of the compression stroke there will be no compression. This will take the load off mains and big ends. (I know that the valves will all be closed but there will still be air above the pistons).
This could be important because without the rockershafts in place there may not be much oil pressure.
Also check that the rocker shafts are fitted the right way round with the oil feed to each rocker pointing towards the valley area.
I'd also pull out the pushrods just to stop them flying about! (Number them so they go back in the same place).
Without the shafts my dizzy driven pump could shoot oil miles into the air when spun with a drill!
OK thanks for the ideas. I've just taken the rocker assembly off as suggested. Turning the engine on the starter, with plugs removed, I do get oil flow through to the rockers - but it is definitely an ooze rather than a spurt!
I swapped the hoses on my remote filter head once again, just to see if there was any difference - but I get the same very limited flow to the rockers either way round.
I just this morning bought a new filter which is identical to the one currently on the engine (Britpart ERR3340), to double check whether it has a non return valve. But TBH I'm still not sure as I can neither blow or suck air through the big hole in the middle! Anyone know for sure if this filter has a non return valve? If it does have one, as I'm assuming, then I don't understand why I see identical pressure and flow with the filter plumbed in opposite directions.
One other thing that could be a factor... The interim timing cover has two ports for an oil cooler. Some time ago, probably about a year back, I was trying to figure out what to do with these ports as I'm not planning to run a cooler. I posted on here, read the Land Rover manual (which states the cooler is optional), and also could see that the two ports are internally connected. So based on all that I decided I could safely blank off both ports. I suppose that could that be causing the restricted flow, if perhaps the internal oil way between the ports is narrow and not designed to take the full flow. Guess I can easily test this by getting a hose made up to connect the ports together - but would prefer some more supporting evidence/opinion before going to the trouble/expense. Any thoughts?
I swapped the hoses on my remote filter head once again, just to see if there was any difference - but I get the same very limited flow to the rockers either way round.
I just this morning bought a new filter which is identical to the one currently on the engine (Britpart ERR3340), to double check whether it has a non return valve. But TBH I'm still not sure as I can neither blow or suck air through the big hole in the middle! Anyone know for sure if this filter has a non return valve? If it does have one, as I'm assuming, then I don't understand why I see identical pressure and flow with the filter plumbed in opposite directions.
One other thing that could be a factor... The interim timing cover has two ports for an oil cooler. Some time ago, probably about a year back, I was trying to figure out what to do with these ports as I'm not planning to run a cooler. I posted on here, read the Land Rover manual (which states the cooler is optional), and also could see that the two ports are internally connected. So based on all that I decided I could safely blank off both ports. I suppose that could that be causing the restricted flow, if perhaps the internal oil way between the ports is narrow and not designed to take the full flow. Guess I can easily test this by getting a hose made up to connect the ports together - but would prefer some more supporting evidence/opinion before going to the trouble/expense. Any thoughts?
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CastleMGBV8
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Adam,
Still worth checking that the oil holes on the rocker shafts are pointing down towards the cam area as Pete suggested.
My other bet from experience is that the oil holes in the heads are blocked or partially blocked.
The heads have oilways front and rear but the block feeds from the front, if the engine has been rebuilt and the heads swapped from bank to bank then the previously redundant oil holes will now be at the front and they are very prone to blocking up when previously unused.
I had to drill out the oil ways on a pair of heads, they were blocked solid.
Try running a bit of stiiff wire down the oil ways, if you meet with reistance then that is the problem, not sure i would just force the wire down the hole as you will be releasing debris into the oil system but if you do then just turn the engine over with the rockers off to push out the residue.
Kevin.
Still worth checking that the oil holes on the rocker shafts are pointing down towards the cam area as Pete suggested.
My other bet from experience is that the oil holes in the heads are blocked or partially blocked.
The heads have oilways front and rear but the block feeds from the front, if the engine has been rebuilt and the heads swapped from bank to bank then the previously redundant oil holes will now be at the front and they are very prone to blocking up when previously unused.
I had to drill out the oil ways on a pair of heads, they were blocked solid.
Try running a bit of stiiff wire down the oil ways, if you meet with reistance then that is the problem, not sure i would just force the wire down the hole as you will be releasing debris into the oil system but if you do then just turn the engine over with the rockers off to push out the residue.
Kevin.
Right, I've been looking at this problem again today - but I still can't figure out what going on.
Here's where I'm at:
- Oil pressure reading 40psi at idle, but hardly any oil getting to rockers
- I've checked the rocker shafts are correctly fitted so that the flow is not obstructed - they are correct
- I've removed a rocker assembly as suggested by Chris - but still only see a steady oozing of oil from the hole - certainly not squirting out as described by others
- I've tried the remote oil filter connected both ways - but this makes no difference to the measured pressure or observed flow (this may be an important symptom as the filter is supposed to have a non return valve and flow oil in one direction only)
- I've had the oil pressure relief valve out, but it seems fine and is not sticking in it's bore
- I've removed the oil cooler port blanking plugs to check they're not obstructing the oil ways internally - they're not
- I've checked the oilway to the rockers is not blocked, as suggested by Kevin, but it's fine
- Finally I thought I'd cracked it when I worked out that my cut n' shut pickup was only about 1 or 2mm from the bottom of the sump and that perhaps this was restricting the flow. So I spent a hour or so modding it to increase the gap and then put everything back together - No cigar!
So all in all I'm more confused than ever!
Here's where I'm at:
- Oil pressure reading 40psi at idle, but hardly any oil getting to rockers
- I've checked the rocker shafts are correctly fitted so that the flow is not obstructed - they are correct
- I've removed a rocker assembly as suggested by Chris - but still only see a steady oozing of oil from the hole - certainly not squirting out as described by others
- I've tried the remote oil filter connected both ways - but this makes no difference to the measured pressure or observed flow (this may be an important symptom as the filter is supposed to have a non return valve and flow oil in one direction only)
- I've had the oil pressure relief valve out, but it seems fine and is not sticking in it's bore
- I've removed the oil cooler port blanking plugs to check they're not obstructing the oil ways internally - they're not
- I've checked the oilway to the rockers is not blocked, as suggested by Kevin, but it's fine
- Finally I thought I'd cracked it when I worked out that my cut n' shut pickup was only about 1 or 2mm from the bottom of the sump and that perhaps this was restricting the flow. So I spent a hour or so modding it to increase the gap and then put everything back together - No cigar!
So all in all I'm more confused than ever!
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ian.stewart
- Forum Contributor
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- Joined: Sat Nov 18, 2006 1:59 pm
- Location: Far Far south, any further south and my feet are wet
AdamR wrote:
One other thing that could be a factor... The interim timing cover has two ports for an oil cooler. Some time ago, probably about a year back, I was trying to figure out what to do with these ports as I'm not planning to run a cooler. I posted on here, read the Land Rover manual (which states the cooler is optional), and also could see that the two ports are internally connected. So based on all that I decided I could safely blank off both ports. I suppose that could that be causing the restricted flow, if perhaps the internal oil way between the ports is narrow and not designed to take the full flow. Guess I can easily test this by getting a hose made up to connect the ports together - but would prefer some more supporting evidence/opinion before going to the trouble/expense. Any thoughts?
This is where I would start - taking out the return blanking plug to see what oil flow/pressure is present and then the flow blanking plug - buckets at the ready.
When the oil cooler is not fitted is the internal porting changed - It certainly is on on my Imp engines - very very different
Andrew
4.5L V8 Ginetta G27
Ian: No Vaseline used, as I've not had the pump off - and the crank driven pumps don't need priming anyway from what I've read.
Andrew: Yep the OEM hoses for connecting an oil cooler block the internal oil way to force the oil through the cooler. I thought that my blanking plugs could be obstructing something, but I've had a good look and they are fine. Running with one r other of the plugs removed is a reasonable idea - but will be very messy as you say!
It also occurred to me this morning that I can remove the oil filter from the equation completely by looping connecting together the outlet and inlet ports on the take off.
Keep the ideas coming!
Andrew: Yep the OEM hoses for connecting an oil cooler block the internal oil way to force the oil through the cooler. I thought that my blanking plugs could be obstructing something, but I've had a good look and they are fine. Running with one r other of the plugs removed is a reasonable idea - but will be very messy as you say!
It also occurred to me this morning that I can remove the oil filter from the equation completely by looping connecting together the outlet and inlet ports on the take off.
Keep the ideas coming!
Hi, if you connect the outlet and inlet ports together then you need to make sure that you have the right sort of fitting on the outlet, it has an internal sleeve and an o-ring to direct the oil up the pipe, otherwise it just circulates within the housing. Altho this should still flow round the motor.
