Discussion
I have been having problems getting oil to the top of the engine in tight corners at high revs. I use my S for autotesting and if the course contains tight enough corners and short enough straights that 2nd gear is impractical then by the end of a run the lifters can be sounding quite unhappy.
Some research suggests this is because there's too much oil at the top of the engine taking too long to get back to the bottom and with less oil in the sump it is being thrown around more and harder for the pump to pick it all up. Getting the oil draining back faster will require taking the engine apart (and resisting the pull of the shiny things) but controlling the oil in the sump shouldn't be too hard with an afternoon spent sticking baffles in.
This leads on to my current problem of trying to work out what sumps are out there and which ones will fit. From what I've read the S uses a 3.9 range rover sump which should be easily available, are later 4.0 and 4.6 sumps the same? I have seen pictures of a shiny aluminium sump from a 4.6, will that fit around the chassis on the S and does that have a lot in the way of baffling?
Some research suggests this is because there's too much oil at the top of the engine taking too long to get back to the bottom and with less oil in the sump it is being thrown around more and harder for the pump to pick it all up. Getting the oil draining back faster will require taking the engine apart (and resisting the pull of the shiny things) but controlling the oil in the sump shouldn't be too hard with an afternoon spent sticking baffles in.
This leads on to my current problem of trying to work out what sumps are out there and which ones will fit. From what I've read the S uses a 3.9 range rover sump which should be easily available, are later 4.0 and 4.6 sumps the same? I have seen pictures of a shiny aluminium sump from a 4.6, will that fit around the chassis on the S and does that have a lot in the way of baffling?
Pretty sure the alloy 4.0 and 4.6 sumps are the wrong length due to a different front cover - I think the RR front cover does not have provision for a distributor - the TVR front cover on later engines is an 'intermediate' cover operating with the later engine but with provision for a distributor - but again I don't think it is compatible with the pre serp front cover.
A bit wordy but in summary I am pretty sure you are stuck with the 3.9 style sump.
A bit wordy but in summary I am pretty sure you are stuck with the 3.9 style sump.
This is in the Steve Heath S book and I would imagine is what's also in the griff book.
Mostly I was wondering whether the newer sumps fit the older engines and having done some more digging I can confirm that they don't, they are quite different at the front end due to the change in the location of the oil filter with the newer front cover, a bit of a shame really.
The plan is to chop out the baffle plate, build a nice set of baffle plates with doors into the bottom around the pickup and then bolt a plate over the top (all the photos I've seen of really expensive baffled sumps all seem to have them welded in, clearly designed by someone who's never tried to clean all the muck out of one when all the water has escaped into the sump)
Thanks for the offers with the griff book but now that I know the shiny pretty one won't fit I will go and acquire another 3.9 one to modify. Thanks for the tip Dave, I will see if it's still there on Saturday.
Mostly I was wondering whether the newer sumps fit the older engines and having done some more digging I can confirm that they don't, they are quite different at the front end due to the change in the location of the oil filter with the newer front cover, a bit of a shame really.
The plan is to chop out the baffle plate, build a nice set of baffle plates with doors into the bottom around the pickup and then bolt a plate over the top (all the photos I've seen of really expensive baffled sumps all seem to have them welded in, clearly designed by someone who's never tried to clean all the muck out of one when all the water has escaped into the sump)
Thanks for the offers with the griff book but now that I know the shiny pretty one won't fit I will go and acquire another 3.9 one to modify. Thanks for the tip Dave, I will see if it's still there on Saturday.
On mine I have a fully baffled and flap valved sump but it still gets out surge on long high speed sweeping bends unless I overfill it. If yours is used for autotesting, you probably don't have sustained high G so you should be able to sort this OK. I would suggest sticking an extra half an inch of oil in the sump, and get a decent baffled and flap valve sump from JE or similar. If you still have trouble you could fit an oil accumulator, but I would be surprised if you needed that.
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