Series 3 Fired the Series 3 up for the first time today. Low oil pressure

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Webley1991

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I started my Series 3 diesel today for the first time since I started the rebuild in May 2013.

The first thing I noticed was what a messy job bleeding the fuel system is. It seems that there is no way to avoid diesel being dripped all over the engine bay, no matter how well you have things covered in rags.

When I finally got the engine to turn over it seemed to run fine, which I would hope so for a fully reconditioned unit. I went to look in the engine bay to check for fuel or water leaks, and there didn't seem to be any. When I got back to the dashboard I noticed that the low oil pressure light was on. I immediately shut it down when I saw this, It must have been running for about two minutes in all.

I checked the oil level before I first started it, which was half way between the high and low mark. After shutting it down and leaving it for a while to drain back, it was now below the low mark. I added enough oil to bring the level back up, and also topped up the radiator.

I started it again and the oil pressure light still didn't go out, so I shut it down straight away.

I remember reading on here that the engine will make a distinctive rattling sound until the oil flows round properly if it has been sat for a while. I didn't notice anything unusual, so would hope that the oil was circulating.

I disconnected the oil pressure sensor with the key at position 1 (electrics only) to see if the connection to the lamp was shorted to earth somewhere. The lamp went out so this is not the case.

I have a spin-on filter holder from a 2.5NA engine fitted, could this be something to do with it?

How would I go about checking if the oil is properly circulating? What possible problems should I try to eliminate first?

I did wonder if the sensor was sticking. I have another of the same type of filter holder with another sensor. I will test the other one, then try swapping them and see what happens.

Once this issue is sorted, about all that is left to do is bleed the last of the air out of the brakes, then fit the side pnaels, roof and rest of the trim. It should then be ready to be put in for an MOT.
 
Take the cap off the rocker cover you should be able to see the oil flowing through the rockers.
When you fitted the sensor did you put any sealant on the threads?
Might not be earthing properly if you did.
 
+1 on the sensor - seen them fail before. If you don't have one, now might be the time to fit an oil pressure gauge - they're a nice thing to have and all my trucks have them.

Alan
 
I started my Series 3 diesel today for the first time since I started the rebuild in May 2013.

The first thing I noticed was what a messy job bleeding the fuel system is. It seems that there is no way to avoid diesel being dripped all over the engine bay, no matter how well you have things covered in rags.

When I finally got the engine to turn over it seemed to run fine, which I would hope so for a fully reconditioned unit. I went to look in the engine bay to check for fuel or water leaks, and there didn't seem to be any. When I got back to the dashboard I noticed that the low oil pressure light was on. I immediately shut it down when I saw this, It must have been running for about two minutes in all.

I checked the oil level before I first started it, which was half way between the high and low mark. After shutting it down and leaving it for a while to drain back, it was now below the low mark. I added enough oil to bring the level back up, and also topped up the radiator.

I started it again and the oil pressure light still didn't go out, so I shut it down straight away.

I remember reading on here that the engine will make a distinctive rattling sound until the oil flows round properly if it has been sat for a while. I didn't notice anything unusual, so would hope that the oil was circulating.

I disconnected the oil pressure sensor with the key at position 1 (electrics only) to see if the connection to the lamp was shorted to earth somewhere. The lamp went out so this is not the case.

I have a spin-on filter holder from a 2.5NA engine fitted, could this be something to do with it?

How would I go about checking if the oil is properly circulating? What possible problems should I try to eliminate first?

I did wonder if the sensor was sticking. I have another of the same type of filter holder with another sensor. I will test the other one, then try swapping them and see what happens.

Once this issue is sorted, about all that is left to do is bleed the last of the air out of the brakes, then fit the side pnaels, roof and rest of the trim. It should then be ready to be put in for an MOT.
Bleeding the fuel system is an acquired technique. I doubt if I would spill more than a few drops bleeding that system. Your technique will improve with practice.
I would guess sensor has failed. If you have a gauge try that. If not, remove rocker cover, start up, and visually check that oil is welling out around the rocker shaft. If it is, oil pump is working.
 
Thanks for the replies.

I may order an oil pressure gauge. You can get them on ebay for about £15.Would I simply connect this into the sensor hole on the filter holder?
http://www.ebay.co.uk/itm/449852-Ca...Garage-Tool-/291510679232?hash=item43df63f6c0

The rocker cover on my engine is the early type without a filler cap. Mine is filled through a pipe bolted to the side of the block. I could remove the breather to visually check, although this would mean breaking the sealant it has been installed with.

As the oil level had dropped when I checked it after shutting down, the oil must have gone somewhere.

Am I right that the part number for the sensor is PRC6387? I removed the unit from the other filter housing I have and it has an M10x1 thread. Were they all the same thread?
 
I have 15w40 Mineral oil in the sump.
I will try connecting a pressure gauge over the weekend.

Another problem I have is I seem to have a short causing voltage to travel down the metal outside covering of the engine stop cable. I only noticed this by chance as the clip on the pump that holds this was hot when I touched it. When I removed the dashboard and tried it again there wasnt a short. All I can think of is that a wire behind the dashboard shorted against the outer casing of the ignition lock.
 
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That's more likely to be a lack of earthing strap on the engine, it's not a short, it's earth current travelling from the engine to the rest of the truck (possibly) - have you got an earth strap between the engine and chassis/bulkhead.
 
What should the oil pressure be at startup from cold? The manual gives it as 35-65 PSI at 2000rpm with the oil warm.
That is quite a large variation.

As for the earthing strap, I have one from the starter motor to the chassis. Does the engine block itself need one as well?
 
Just as a number my 2.25s tend to run 20 PSI or so with oil warm - that's 15W40 oil and engine at operating temperature.

I might suggest that if your stop cable is getting warm there is a definite issue with your grounding whether the cable is there or not - it's lying down on the job. :)

When I re-cable a Series truck I take the ground lead straight to the engine block, then from there back to the battery box for the truck feeds. Seems to me that the major part of the current and the charging current are going to come straight onto and off the engine, and it should be the closest linked to the battery witht he chassis after that.

More the point, i'd have a look at the grounding of the negative battery cable at the battery box - there is definitely a voltage drop somewhere there.

Alan
 
I started the engine again today with a pressure gauge connected. It turns out that the oil pressure sensor had failed.

The gauge rose to 66 PSI almost straight away and sat there as the oil warmed up. When I revved the engine it actually rose to nearer 70. Is that just because th eoil pump is brand new with no wear?

I also have a few othe problems. One is that coolant is leaking from the heater control valve.

The other is the fuel filter housing leaking diesel from around the joint between the bottom of the filter and the zinc housing. I tightened the centre bolt up pretty tight and it's still leaking. I don't want to go too far in case I strip the thread. Should a non-hardening gasket compound such as hylomar blue by used on assmebly?

I have read that some series vehicles have had filter housings from defenders fitted which take the modren type filters. This would eliminate the prioblem of leakage from the bottom. Has anyone here done this?

Other than that, all I need in the rest of the dasboard trim, side panels, winscreen and roof on and I should be ready to put it in for an MOT. Today I was able to drive out into the yard under the vehicle's own power for the first time since the rebuild started.
 
I started the engine again today with a pressure gauge connected. It turns out that the oil pressure sensor had failed.

The gauge rose to 66 PSI almost straight away and sat there as the oil warmed up. When I revved the engine it actually rose to nearer 70. Is that just because th eoil pump is brand new with no wear?

I also have a few othe problems. One is that coolant is leaking from the heater control valve.

The other is the fuel filter housing leaking diesel from around the joint between the bottom of the filter and the zinc housing. I tightened the centre bolt up pretty tight and it's still leaking. I don't want to go too far in case I strip the thread. Should a non-hardening gasket compound such as hylomar blue by used on assmebly?

I have read that some series vehicles have had filter housings from defenders fitted which take the modren type filters. This would eliminate the prioblem of leakage from the bottom. Has anyone here done this?

Other than that, all I need in the rest of the dasboard trim, side panels, winscreen and roof on and I should be ready to put it in for an MOT. Today I was able to drive out into the yard under the vehicle's own power for the first time since the rebuild started.
Pretty much what everyone posted, then!:)

Fuel filter has four sealing rings, all different sizes, they must be in good condition and in the right places for it to seal. Don't use sealant, and don't overtighten it.
Britpart, Fram and similar rubbish often don't seal, throw away if present, and get a Delphi. New filter has all rings with it. Defenders use a completely different filter head and element. Sure you can swap it but with pipe mods, CAV is perfectly good if it is right.
 
Thanks for the reply.

I used a set of Delphi seals when I assembled the filter hosuing. The filter itself is branded Perkins Powerpart.
 
Yes I didfit both rings. I removed the old ones as well. I fully cleaned and degreased the filter holder when I took it apart so they definitely didn't get left in there.
 
The engine was fitted with a new lift pump when it was rebuilt. Unfortunately it seems to be weeping diesel when pumped by hand and when the engine is running.

Does this mean that it requires a replacement seal kit, or would I be better off replacing the whole thing? I would think that a new unit should be completely dry.

When I disassembled the fuel filter holder to replace the seals, I noticed some very fine metallic particles on the "in" side of the fuel filter unit. This doesn't seem like a good sign.
 
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