M

MattHarris

New Member
As per previous thread, oil indicator light indicates low pressure, following recent head gasket change. The garage are pushing me to change the whole engine, but a brief interweb search suggests there could be a few different causes for low oil pressure (knackered pump etc). How would HGF damage the rest of the engine to the extent that it needs to be replaced, and is is possible to diagnose this purely on the basis of the oil pressure gauge which flickers when the car is idling?
 
HGF shud not affect oil pressure at all.

Mind you - I have known peeps do such an inept job that they seal oil passage ways with Hylomar or similar, which stops oil getting thru to things like rocker shafts which will then sieze due to lack of oil. This, however will not show up as low oil pressure via the switch.

Check those wires and, if necessary, change sensor.
Might be worth checking things are done up tight and not leaking....
 
Thanks for that. I think the implication was that the HGF had somehow damaged the rest of the engine, a symptom of which being that oil pressure was low.

I'm not a mechanic, but I did think it was a big leap from 'your oil pressure light is flickering' to 'you need a whole new engine'.
 
MattHarris said:
As per previous thread, oil indicator light indicates low pressure, following recent head gasket change. The garage are pushing me to change the whole engine, but a brief interweb search suggests there could be a few different causes for low oil pressure (knackered pump etc). How would HGF damage the rest of the engine to the extent that it needs to be replaced, and is is possible to diagnose this purely on the basis of the oil pressure gauge which flickers when the car is idling?
Click to expand...

errr, normal diagnostic procedure is to remove sender and get a definitive pressure reading with a reliable test gauge!
 
Chaser said:
errr, normal diagnostic procedure is to remove sender and get a definitive pressure reading with a reliable test gauge!
Click to expand...

Ok I'll ask if they've done that, but it sounds to me as though they've just fired it up, noticed the flickering oil gauge, and extrapolated from there.

Supposing the test gauge reading indicated low pressure, would a faulty oil pump be the first suspect? And thereafter, how far down the list of eliminated suspects would 'a completely broken engine which needs replacing' be?

Matt
 
Once you prove low pressure then it's engine out or sump off if that's possible in situ and check crank and oil pump and go from there depending on what is found.
 
Apparently the oil pressure has been tested and found to be low (although the guy didn't sound too convincing, but you have to take their word for it I s'pose) and he's '90%' sure it's the oil pump, which has been damaged by the head-gasket failure. Can anyone explain (in simple terms) how HGF would damage the oil pump?

Thanks
 
No :(

Ask him to explain as yu wish to claim off your insurance and need a written statement of how it could have happened ;).
 
The Mad Hat Man said:
No :(

Ask him to explain as yu wish to claim off your insurance and need a written statement of how it could have happened ;).
Click to expand...

Sorry, is that 'no' you don't know how HGF could break the oil pump, or 'no' HGF shouldn't damage the oil pump? Ta.

Also, 'cos the HGF repair has approached the 'per-claim' limit, the idea is to treat the oil pump failure as a separate issue (which of course it may be) and therefore make a separate claim.
 
MattHarris said:
Sorry, is that 'no' you don't know how HGF could break the oil pump, or 'no' HGF shouldn't damage the oil pump? Ta.

Also, 'cos the HGF repair has approached the 'per-claim' limit, the idea is to treat the oil pump failure as a separate issue (which of course it may be) and therefore make a separate claim.
Click to expand...

'no' I don't know how HGF could break an oil pump
because
HGF shouldn't damage the oil pump.

those two statements are not mutually exclusive.

I cannot see any way in which an HGF could damage an oil pump.......... except
If the HGF was run so long that the engine completely cooked, ran all the bearings dry and distorted the block sufficiently that all the oilways were buggered.

I think you would have noticed that.
 
Last edited:
Now it's the pressure release valve related to the oil pump with is most likely the problem. Apparently this is a notorious defect on this model - anyone else heard of this? I'd heard of the HGF problem from the various websites (and yes I still bought one anyway) but not prssure release valve.
 
Just quickly looked at a diagram as I know feck all about these particular engines. Oil pump is external on the front of the engine behind the crank pulley and cambelt so it looks at least to be a straight forward job. If he is convinced it's the relief valve at fault then from the diagram it appears that the relief valve can be accessed without pump removal so shouldn't be a big deal if it just needs some cleaning/checking to get it to re-seat.
 
The Mad Hat Man said:
'no' I don't know how HGF could break an oil pump
because
HGF shouldn't damage the oil pump.

those two statements are not mutually exclusive.

I cannot see any way in which an HGF could damage an oil pump.......... except
If the HGF was run so long that the engine completely cooked, ran all the bearings dry and distorted the block sufficiently that all the oilways were buggered.

I think you would have noticed that.
Click to expand...


**** MHM your learning....

Maybe I missed it but cant see what motor you have got but the main 2 suspects are ...

oil pick up "O" ring or the oil pick up pipe itself either being blocked (by scum thats been disturbed by previous work) or leaking air through the plastic weld.....new pipe and o ring costs about 40 quid and an hour to replace....

also could be caused by a blocked oil cooler (if v6 you will have to remove this to do above) get it off and check its clear.....
 
You must log in or register to reply here.

Similar threads

G
Oil pressure switch thread ?
Replies
2
Views
238
grewth
G
mad85
Disco 2 TD5 Low Fuel pressure!!
2
Replies
22
Views
686
mad85
mad85
Bife
Freelander 1 Sand Tyre Pressure, how low is low?
Replies
7
Views
532
Bife
Bife
S
Disco4 rough idle after injector issues
Replies
8
Views
435
Stevie135
S
miktdish
Oil pressure gauge
Replies
5
Views
1K
Al2O3
Al2O3