using oil on a new built engine ? how much do you use?

TVR Beaver · Post by **TVR Beaver** » Sun Nov 10, 2013 10:24 pm

I re-built my 500 last winter, getting new pistons and a re-hone amongst other things.
Having fitted a new cam the first thing I did was run the cam in (3K for 20 mins) then took the car on the road and gave it some loading up and down hills for 30 mins.. then ran it hard for about 800 miles all on cheapo mineral oil.... I didn't notice if it used much ... TBH I was not looking, but having put some semi-synth in it and taken it for a 320 mile run, i found it had used over 1/2 a ltr!!
So I put Valvoline vr1 20/50 mineral in and thats what I'm now running.. its done about 2000 miles this year and on the Valvoline its doing about 1200 miles per Ltr. this is about 5 times worst than it was doing before the re-build!
The compression on all pot is withing 5% and is about 14 bar... no oil in breather tubes and no smoke.. its like its taking a metered amount and using it?...
I was thinking bore glazing due to running in the cam (but then the CR would not be this good??)... or the fact that it may be just taking it from the honing every stroke as it still need more miles to fully bed in?.. any thoughts on this and the amount used??

kiwicar · Post by **kiwicar** » Mon Nov 11, 2013 7:30 am

Hi
are you 100% positive you have the right dip stick? If you are constantly trying to over fill it you will chuck the extra out very quickly and it will seem to use a lot of oil. Can I suggest you drain it all down and put in the correct amount, then see where it comes on the dip stick and see how much it consumes at that level.
Best regards
Mike

TVR Beaver · Post by **TVR Beaver** » Mon Nov 11, 2013 8:50 am

yes.. its good. It goes to 1/2 way with the recomended amount in there... and is also the same dipstick / tube as before the re-furb that I had no issues with. Also vent tubes are very clean...

SimpleSimon · Post by **SimpleSimon** » Mon Nov 11, 2013 10:26 am

TVR Beaver wrote:yes.. its good. It goes to 1/2 way with the recomended amount in there... and is also the same dipstick / tube as before the re-furb that I had no issues with. Also vent tubes are very clean...

Just because it as good compressions is no indicator of the oil control rings doing their job properly , run it for a couple more thousand miles and see if things improve

what have you got to loose

TVR Beaver · Post by **TVR Beaver** » Mon Nov 11, 2013 11:47 am

but is it that bad?.. if it were oil contol rings it would be drinking it?... its all very strange?

Ian Anderson · Post by **Ian Anderson** » Mon Nov 11, 2013 12:56 pm

It sounds about the same when I got my GT40 on the road a number of years ago

It used a fair amount and I kept topping it up

After about 3000 miles the need to top up the oil slowed down

2 years back 800 mile round trip to Le Mans and a full 1/2 hour on track at hard running and no noticable oil use

Run it a bit more and keep an eye on the oil

also check all the plugs because if 1 oil control ring is knackered a lot of oil in 1 cylinder will show up on the plug

Ian

TVR Beaver · Post by **TVR Beaver** » Mon Nov 11, 2013 1:08 pm

yes, two years ago we went to LeMans and it used about 3mm in 1200 miles

Nothing on the plugs.. they look fine

What oil were you using in yours ?

Ian Anderson · Post by **Ian Anderson** » Mon Nov 11, 2013 6:28 pm

castrol Classic 20/50

Steeled to be fine
Ian

kokkolanpoika · Post by **kokkolanpoika** » Mon Nov 11, 2013 6:36 pm

Did you measure piston/bore clearance?
I have read, that if you use aftermarket rockers, the clearance is to big, then you will get to mutch oil at the top end, and oil is escaping between valve/valve guide..

And Valvoline VR1 20w50 is not "long life" oil, it is racing oil, designed to short runs.. It will lose some polymer´s or parameters etc in very short time..

My 5.2litre also eat some Valvoline VR1 20w50 oil.. 1l approx 1000km. Usually first 1000km it will eat approx 0.8l and after 1000 to 2000km it will eat 1l..
I try to use Mobil 5w50 peak life, oil consumption is near zero, but i will lose some oil pressure at idle speed (approx 0.2bar less)

I have seen some toyota avensis 1.8petrol engine.. Our local shop made rebuild.. Bore + hone etc.. It wont eat any oil before rebuild, but affter rebuild, it will eat 1l/1000km.. They dissemble it, all looks ok, not glazed.. They make fine hone to cylinder again, new rings again, same problem.. They did never resolve this problem..

ppyvabw · Post by **ppyvabw** » Mon Nov 11, 2013 7:16 pm

I had this problem on a B series engine I rebuilt several years ago. Was using roughly a 1L/1000 miles. I nearly took it apart again, but instead I kept running it and it did seem to get slightly better, but it always used some. I just used ordinary oil from the outset.

I don't know what you more knowledgeable chaps think, but I wonder if modern oils are so much better than they used to be that if you use them in a new engine from the first run, it just never lets the rings bed in; so you should use running in oil. Having said that, I used normal oil from the outset in my current V8, and it barely uses a drop.

TVR Beaver · Post by **TVR Beaver** » Mon Nov 11, 2013 7:39 pm

yes, I measured the bores and pistons and they were within limits.....
nothing getting down the guides as I have new seals on there....
I may just put some running in oil back in there and use it for another 1K.. see what happens.
TBH some of the TVR guys on the bigger engines say 1 Ltr / 1000 miles is okay.. but I think its a bit much

Mobil peak life?.. not sure it will be okay for the V8 with a heavy cam.. we need a bit of zinc you know

sidecar · Post by **sidecar** » Mon Nov 11, 2013 7:52 pm

From what I've read you should avoid semi-synth or fully synth oil for a few thousand miles on a newly built engine. (maybe 2k miles). If you bung it in the engine too soon the rings will not bed in. Mind you I've also read that the rings are more or less bedded in after a few hundred miles.

The problem that I can see is that running the engine under no load for 20 minutes is bad for the rings yet required for the cam, it's a tricky situation.

I guess the cam does not care if the engine is under load or not, it just wants the revs up at over 2.5k, the problem is that driving the car whilst keeping the revs this high with the engine under load would be hard to do.

I guess a dyno is the anwser.

The bores weren't plateau honed were they?

SimpleSimon · Post by **SimpleSimon** » Mon Nov 11, 2013 9:27 pm

TVR Beaver wrote:but is it that bad?.. if it were oil contol rings it would be drinking it?... its all very strange?

You seem to think so thats why you have asked, I would just monitor oil usage over a few thousand miles its certainly not excessive

things may even improve with mileage as Ian Anderson said

TVR Beaver · Post by **TVR Beaver** » Mon Nov 11, 2013 11:04 pm

yes is was plateau honed on the machine at TVR Power.. and quite a rough hone I thought?.. so could still be bedding in?...
.
The comment on the rings.. what I should have said is ... if it was the oil control ring, it would be using a lot more than it is... I don't think its its this because it's not a massive loss... but yes, I do think its a lot to burn (although others say its normal?) and I would like to improve it.

May be time and a few more miles, and the right oil is the answer??

SimpleSimon · Post by **SimpleSimon** » Mon Nov 11, 2013 11:23 pm

A plateau hone is a fine hone (well should be) not a course hone

quite sure Power know whats needed for the RV8 though

give it some mileage Beaver