What leads you to believe the oil pump is on its way out? I was always under the impression they don't give a lot of trouble as a rule
An oil pump is one of those things I'd replace with a new one personally, being such a critical component.
DW8 engine caput
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CitroJim
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Good work Nigel, excellent effort
What leads you to believe the oil pump is on its way out? I was always under the impression they don't give a lot of trouble as a rule
An oil pump is one of those things I'd replace with a new one personally, being such a critical component.
What leads you to believe the oil pump is on its way out? I was always under the impression they don't give a lot of trouble as a rule
An oil pump is one of those things I'd replace with a new one personally, being such a critical component.
Jim
Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
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ideally i want a new one but there must be aftermarket ones available.
when the engine gets hot say ive been going down the motorway and i come to the slip road and it idles the light comes on for around 3-5 seconds. then goes out. im guessing as the oil heats and gets thiner the oil pump is struggling to maintain the pressure. really dont want to rebuild the damm thing again lol.
ive tried different oils from cheap to expensive and they dont make a difference.
when the engine gets hot say ive been going down the motorway and i come to the slip road and it idles the light comes on for around 3-5 seconds. then goes out. im guessing as the oil heats and gets thiner the oil pump is struggling to maintain the pressure. really dont want to rebuild the damm thing again lol.
ive tried different oils from cheap to expensive and they dont make a difference.
!BORN TO FIX!
Your dropping oil pressure sounds like a serious problem and needs to be traced while you are working on the engine.
The most likely cause is main bearings but other things like camshaft bearings can affect the pressure. If you dismantle the pump you may find enough evidence to blame it - but unless evidence is found there I'd investigate further, remove the crank, have it measured and reground if necessary and re-fit it with new shells in any event.
Most Citroen diesels have an oil/water heat exchanger sitting under the filter. This is often described as a cooler but in fact it probably uses the water to heat the oil at startup and cools it thereafter. Is it still there and are the water hoses connected?
The most likely cause is main bearings but other things like camshaft bearings can affect the pressure. If you dismantle the pump you may find enough evidence to blame it - but unless evidence is found there I'd investigate further, remove the crank, have it measured and reground if necessary and re-fit it with new shells in any event.
Most Citroen diesels have an oil/water heat exchanger sitting under the filter. This is often described as a cooler but in fact it probably uses the water to heat the oil at startup and cools it thereafter. Is it still there and are the water hoses connected?
jeremy
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yes the pipes are there. the crank has just been polished and new shells fitted but it was only after all this work that it stated to doit. before this the oil had not been changed for around 50k and i assumed that this thick oil hid the problem as all the big end bearing were knackered.
!BORN TO FIX!
My point is that its all to easy to overhaul something according to the book and find that the fault is still there when you've finished the job.
The DW8 oil pump is probably huge - the TD XU ones are - - similar design to the N/A ones - just half as long again or something - the result being that TD (and 16 valve BX) engines run at a very high pressure even at idle. My BX TD puts its oil pressure warning light out extremely quickly even at 206,000 miles and the light never comes on at idle.
So - at the very least I'd dismantle the pump and examine it for wear and scoring. - I think Haynes gives instructions for measuring its clearances.
The DW8 oil pump is probably huge - the TD XU ones are - - similar design to the N/A ones - just half as long again or something - the result being that TD (and 16 valve BX) engines run at a very high pressure even at idle. My BX TD puts its oil pressure warning light out extremely quickly even at 206,000 miles and the light never comes on at idle.
So - at the very least I'd dismantle the pump and examine it for wear and scoring. - I think Haynes gives instructions for measuring its clearances.
jeremy
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i dont have and haynes manuals or though i did try to get one as all i want it for is the wiring diagram for my indicators as they havent worked for 4 months. tit has done 300,00 miles i puts the light out if you touch the throttle while its idleing and i mean you only need to increase the idle 100-200 rpm. did increase the idle with the screw to help the problem but not really done anything.
It is a big unit but only of what you can see which is mainly the pickup, housing, pressure relief valves, and mounting. i imagine inside all that is quiet a small pump really.
But ultimately yes you are right i am being lazy! the thought of taking all the bearings of and big ends doesnt appeal to me nor does the cost of all the new bolts just to find out. so i think im gonna change the pump first as at the end of the day a new one isnt gonna hurt nor break the bank.
It is a big unit but only of what you can see which is mainly the pickup, housing, pressure relief valves, and mounting. i imagine inside all that is quiet a small pump really.
But ultimately yes you are right i am being lazy! the thought of taking all the bearings of and big ends doesnt appeal to me nor does the cost of all the new bolts just to find out. so i think im gonna change the pump first as at the end of the day a new one isnt gonna hurt nor break the bank.
!BORN TO FIX!