High power turbo engine using oil
Discussion
So Im on a mission to discover and resolve why my Noble uses oil, lots of oil.... as a stock car it used very little and when i started modifying it I also started to maintain it and thus i would check the oil far more regularly and top up as required which makes it hard to judge how much it actually uses.
Anyhow I did a trip around Europe last year and took 2 litres of oil with me (space was tight and that would be more than enough for 2k miles surely)... anyhow 700miles later in Avignon I checked my oil, it was on the min (it takes 9 litres).... clearly i ended up using the 2 litres of oil there and then and then drove carefully for the next 700miles to Lemans, so no boost and mostly just cruising at 90mph, when i arrived it needed 2 litres again (friend bought some oil to lemans for me).
So facts on the car...
It doesn't drip even the smallest amount, breather exits under the car so any oil coming out there would drip.
No blue smoke at all.
Brief black smoke on cold start (its deliberately rich to help start it).
No oil in water system.
No oil in the intercooler.
Black smoke on throttle as its running rich.
I run a oil cooled turbo so removed the standard restrictor.
EGT in manifold (pre turbo) are high even on cruise, 650deg c plus on idle.
Oil pressure is 30psi on idle and a solid 50-60psi once rev'd.
Turbo doesn't have any significant play, its a variant of a BW S300SX.
Its always used oil after all the full engine builds (I've melted pistons and dropped valves so have effectively had new engines each time).
Now I appreciate the oil must be going out the exhaust somehow, but the pipe is sooty but not oily... Valve seals would give blue smoke on start, rings would give blue smoke on boost, if the breather was an issue it would drip oil and not do it when driven carefully.
So im kinda left with a theory that me not running the oil restrictor means i might be pushing oil past the turbo oil seal (hot side as nothings coming out the cold side).... but Ive not got much experience with this kind of issue and don't know if this would burn off or actually cause more blue smoke than some of the other suspects.
Whilst my turbo works really well it is old school and I am tempted to upgrade to roller bearing (prob EFR9180)... but its quite some work and i might need the cash to do a full refresh to find the issue... so I thought id ask for views from some of the turbo experts on here who may have a good idea what the hell the engine is doing lol.
Anyhow I did a trip around Europe last year and took 2 litres of oil with me (space was tight and that would be more than enough for 2k miles surely)... anyhow 700miles later in Avignon I checked my oil, it was on the min (it takes 9 litres).... clearly i ended up using the 2 litres of oil there and then and then drove carefully for the next 700miles to Lemans, so no boost and mostly just cruising at 90mph, when i arrived it needed 2 litres again (friend bought some oil to lemans for me).
So facts on the car...
It doesn't drip even the smallest amount, breather exits under the car so any oil coming out there would drip.
No blue smoke at all.
Brief black smoke on cold start (its deliberately rich to help start it).
No oil in water system.
No oil in the intercooler.
Black smoke on throttle as its running rich.
I run a oil cooled turbo so removed the standard restrictor.
EGT in manifold (pre turbo) are high even on cruise, 650deg c plus on idle.
Oil pressure is 30psi on idle and a solid 50-60psi once rev'd.
Turbo doesn't have any significant play, its a variant of a BW S300SX.
Its always used oil after all the full engine builds (I've melted pistons and dropped valves so have effectively had new engines each time).
Now I appreciate the oil must be going out the exhaust somehow, but the pipe is sooty but not oily... Valve seals would give blue smoke on start, rings would give blue smoke on boost, if the breather was an issue it would drip oil and not do it when driven carefully.
So im kinda left with a theory that me not running the oil restrictor means i might be pushing oil past the turbo oil seal (hot side as nothings coming out the cold side).... but Ive not got much experience with this kind of issue and don't know if this would burn off or actually cause more blue smoke than some of the other suspects.
Whilst my turbo works really well it is old school and I am tempted to upgrade to roller bearing (prob EFR9180)... but its quite some work and i might need the cash to do a full refresh to find the issue... so I thought id ask for views from some of the turbo experts on here who may have a good idea what the hell the engine is doing lol.
All the engines have used oil, various different pistons used finish is standard ford.... in fact my engine is identical to other high powered cars which don't use oil... however they run twin turbos and are water cooled units.
Plugs always look 'rich' dirty as des tail pipe... its soot and never wet or oily as is the tailpipe.
I had a new core in the turbo few years back along with a refresh, it still used oil afterwards although i never monitored it.
Block has a breather as do both the heads and they go into a pro alloy tank which vents under the car via a pipe (which is dry), return for the breather is via the front of the sump, turbo return is rear or sump but way above oil level.
Plugs always look 'rich' dirty as des tail pipe... its soot and never wet or oily as is the tailpipe.
I had a new core in the turbo few years back along with a refresh, it still used oil afterwards although i never monitored it.
Block has a breather as do both the heads and they go into a pro alloy tank which vents under the car via a pipe (which is dry), return for the breather is via the front of the sump, turbo return is rear or sump but way above oil level.
Rings are ford, finish on block has been machined/honed, but has also previously been stock ford as have had brand new block previously. Had new valve guides and seals as well.
Going to do compression leak test, but given that its always used oil after each build/rebuild and made huge power each time (more than almost all other nobles due to the turbo package) its unlikely to be an issue with poor rings etc as it wouldn't loose oil when not on boost... not ruling it out though as in all fairness i have no idea where it is going lol
Going to remove the exhaust and look at the turbo and see if i can see oil there, i already checked the other side and it was all clean with no traces.
Going to do compression leak test, but given that its always used oil after each build/rebuild and made huge power each time (more than almost all other nobles due to the turbo package) its unlikely to be an issue with poor rings etc as it wouldn't loose oil when not on boost... not ruling it out though as in all fairness i have no idea where it is going lol
Going to remove the exhaust and look at the turbo and see if i can see oil there, i already checked the other side and it was all clean with no traces.
So following this thread of it possibly being rings or bore finish.... One thing my car is different is that it runs rich, could I have glazed the bores and caused the issue.... in my head leaking rings would pressurise the block rather than let loads of oil into the combustion chamber and I don't think i am getting any breathing issues as that would cumulate in either oil leaks or the breather exit being oily and i don't have either!
BTW I have experimented with different grades of oil, i now run a slightly thicker oil than others. also every noble out there uses the same ford rings regardless of piston as the 'new' pistons were designed to replicate the ring design (no idea why as they are not exactly cheap on their own). I don't have total seal rings or anything so fancy.
BTW I have experimented with different grades of oil, i now run a slightly thicker oil than others. also every noble out there uses the same ford rings regardless of piston as the 'new' pistons were designed to replicate the ring design (no idea why as they are not exactly cheap on their own). I don't have total seal rings or anything so fancy.
Little update
Not stripped the engine as i don't have a clean enough environment, however i have removed the turbo and already discovered 4 quite important issues:
1. There was a 15mm broken circlip stuck in the entrance of the turbo drain to the sump, thats in the actual oil ways itself and must have come off the shaft.... there is no play back and forth and only a little side to side (not excessive and might just be normal play for a float bearing turbo).
2. The inlet manifold and inlet valve runners have a film of wet oil, nothing major but its there and has ben cleaned only a few hundred miles earlier (as I've had it off to trial fit the ITB's)... there is absolutely NO film of oil before the throttle blade, in the intercooler or any of the plumbing from the turbo to the throttle.
3. One of the exhaust valves stems are wet within the head, clearly valve stem on that particular cylinder are gone, the others i could get to were dry and seemed OK.
4. 2 of the plug leads were wet with very dirty water, the worst was hidden under the inlet manifold and could never have had water ingress from rain etc.
Basically its well worn... Valve stem seals are clearly gone in the exhaust and inlet, turbo is coming apart and must be letting oil past the exhaust seals and i have a possible head gasket issue.
Good job its being rebuilt
I already had plans for the rebuild, fit an EFR9180 and Syvec S8 over winter along with the ITB's and DBW... only downside is i won't get a direct before and after comparison of the ITB's.
Incidentally we tested my ITB's on a totally stock NA engine.... they were slightly better low down, lost power between 4500-6500rpm however they didn't drop away after 6500 like the stock manifold. Stock NA engine redlines at 7000rpm and comparison is against a stock Plenum designed for the stock NA engine so i never expected to beat it.
Currently for my engine I am 'capping' the torque (using boost) between 4000-6000rpm and then increasing the boost higher up to allow the engine to rev to its 8000rpm redline.... so initially it looks like the calculations on runner lengths are spot on and its going to do exactly what i wanted i.e. to flatline the torque till redline.
Oh and they sounded glorious
Proof will be when i get it on the dyno on actuator pressure probably sometime early next year.
Not stripped the engine as i don't have a clean enough environment, however i have removed the turbo and already discovered 4 quite important issues:
1. There was a 15mm broken circlip stuck in the entrance of the turbo drain to the sump, thats in the actual oil ways itself and must have come off the shaft.... there is no play back and forth and only a little side to side (not excessive and might just be normal play for a float bearing turbo).
2. The inlet manifold and inlet valve runners have a film of wet oil, nothing major but its there and has ben cleaned only a few hundred miles earlier (as I've had it off to trial fit the ITB's)... there is absolutely NO film of oil before the throttle blade, in the intercooler or any of the plumbing from the turbo to the throttle.
3. One of the exhaust valves stems are wet within the head, clearly valve stem on that particular cylinder are gone, the others i could get to were dry and seemed OK.
4. 2 of the plug leads were wet with very dirty water, the worst was hidden under the inlet manifold and could never have had water ingress from rain etc.
Basically its well worn... Valve stem seals are clearly gone in the exhaust and inlet, turbo is coming apart and must be letting oil past the exhaust seals and i have a possible head gasket issue.
Good job its being rebuilt
I already had plans for the rebuild, fit an EFR9180 and Syvec S8 over winter along with the ITB's and DBW... only downside is i won't get a direct before and after comparison of the ITB's.
Incidentally we tested my ITB's on a totally stock NA engine.... they were slightly better low down, lost power between 4500-6500rpm however they didn't drop away after 6500 like the stock manifold. Stock NA engine redlines at 7000rpm and comparison is against a stock Plenum designed for the stock NA engine so i never expected to beat it.
Currently for my engine I am 'capping' the torque (using boost) between 4000-6000rpm and then increasing the boost higher up to allow the engine to rev to its 8000rpm redline.... so initially it looks like the calculations on runner lengths are spot on and its going to do exactly what i wanted i.e. to flatline the torque till redline.
Oh and they sounded glorious
Proof will be when i get it on the dyno on actuator pressure probably sometime early next year.
So to update this thread... I had an experienced engine builder round so we can strip/inspect my engine.
First job leak down test, apparently 10% max on a rebuilt engine and 20% indicates an issue needing sorting.
3 were 10%, 2 were 18-20% one was 70%... lea was from the inlet valves!
Inspection of the cam showed mild marking were I clearly had experienced valve bounce (i have upgrade springs), however one lobe had a huge impact probably 0.5-1mm deep and a proper indentation if the rocker shape.... this was the exhaust valve on the same cylinder the intake was leaking 70%!
As mentioned earlier the valve stems had failed on a number of the exhaust and intake valves.. therefore after all these issues we hoped the bottom end would be ok.
Unfortunately not.
Piston to bore gap was 280 tho.... and of cause the bores were now out of shape slightly as a result, pistons were worn with very small signs of Det I told probably caused by reduced octain due to it using so much oil.
Bore clearence at the base of the block where wear was almost zero was still way outside tolerance so it seems I should have had new pistons at the last rebuild (something i was unaware of). Also the pistons I was running are max oversize anyhow.
One fact of note is that I cant get the same cosworth pistons again without ordering 10 sets which was probably the reason the pistons were reused last time (All moaning aside had I known i would have still run them last time as I didn't have the funds for new pistons etc then, it was supposed to be a simple check over refresh).
So I need almost an entire new engine... either get the block re-sleeved or start again and pay £500 to have the spray squirters machined into a new block.
Crank, rods and hopefully valves can be reused.
Anyone have a good guide as to how much decent sleeves will cost for 6 cylinders?
First job leak down test, apparently 10% max on a rebuilt engine and 20% indicates an issue needing sorting.
3 were 10%, 2 were 18-20% one was 70%... lea was from the inlet valves!
Inspection of the cam showed mild marking were I clearly had experienced valve bounce (i have upgrade springs), however one lobe had a huge impact probably 0.5-1mm deep and a proper indentation if the rocker shape.... this was the exhaust valve on the same cylinder the intake was leaking 70%!
As mentioned earlier the valve stems had failed on a number of the exhaust and intake valves.. therefore after all these issues we hoped the bottom end would be ok.
Unfortunately not.
Piston to bore gap was 280 tho.... and of cause the bores were now out of shape slightly as a result, pistons were worn with very small signs of Det I told probably caused by reduced octain due to it using so much oil.
Bore clearence at the base of the block where wear was almost zero was still way outside tolerance so it seems I should have had new pistons at the last rebuild (something i was unaware of). Also the pistons I was running are max oversize anyhow.
One fact of note is that I cant get the same cosworth pistons again without ordering 10 sets which was probably the reason the pistons were reused last time (All moaning aside had I known i would have still run them last time as I didn't have the funds for new pistons etc then, it was supposed to be a simple check over refresh).
So I need almost an entire new engine... either get the block re-sleeved or start again and pay £500 to have the spray squirters machined into a new block.
Crank, rods and hopefully valves can be reused.
Anyone have a good guide as to how much decent sleeves will cost for 6 cylinders?
There are pistons available off the shelf (JE and diaomond etc), but they are a downgrade from the cosworth ones I have now (have used the other in the past).... I gained nearly 50 bhp on 0.6bar actuator pressure when I changed to these pistons and it was very noticeable on the road.
Im considering getting wossner to do me some custom pistons.
Block needs liners, it’s already taken out more than I’d like.... I need as much strength in it as I can get. I’ve scrapped previous blocks with less damage/ wear.
I want the engine 110% ready for me to put the ITBs and DBW on
Im considering getting wossner to do me some custom pistons.
Block needs liners, it’s already taken out more than I’d like.... I need as much strength in it as I can get. I’ve scrapped previous blocks with less damage/ wear.
I want the engine 110% ready for me to put the ITBs and DBW on
Wossner use the same material as Cosworth I'm told, i would be replicating what i have.
Do you have experience of them? or is there any meaningful feedback about them... i've been recommended sung them by someone who has far better experience than me but don't want to put anything sub standard in the engine.
regarding the power increase, the piston is different from the JE ones although i have no idea if they changed the CR or not... I will find that out when i get everything measured.
Do you have experience of them? or is there any meaningful feedback about them... i've been recommended sung them by someone who has far better experience than me but don't want to put anything sub standard in the engine.
regarding the power increase, the piston is different from the JE ones although i have no idea if they changed the CR or not... I will find that out when i get everything measured.
Ok advice on pistons is noted.... Id rather have the cosworth ones as they made more power than the JE ones, probably because they are a better design and CR... the only JE one I kept was a melted one so i can't weigh them to see if there is a significant weight difference (which might be the reason the gain occurred).
Trouble is 8 sets have to be ordered and last time it took a while to sell them all hence the company that got them made are not interested in doing it again... and I can't afford 8 sets!
I was going to get Wossner copy the ones I have now although id want an exact copy including weight and material.
Back to the drawing board
Trouble is 8 sets have to be ordered and last time it took a while to sell them all hence the company that got them made are not interested in doing it again... and I can't afford 8 sets!
I was going to get Wossner copy the ones I have now although id want an exact copy including weight and material.
Back to the drawing board
Evoluzione said:
andygtt said:
I was going to get Wossner copy the ones I have now although id want an exact copy including weight and material.
Do it then, ring Wossner dealers PEC and see what they say.NOTHING can replace genuine experience which is why I'm prepared to listen to a select few who i know have vastly more experience at this level of charged motors... hence I am all ears.
No rear rush as Im still developing a new box for the car to take the extra power, i just don't like not having a plan.
Incidentally and internally identical engine to mine (one of the few that bought the cosworth pistons when i did) made 945bhp on race fuel with a new inlet manifold design (old one was holding us back), previously it made 750bhp on race fuel (his is twin turbo).... My engine was making 646bhp at the hubs on road fuel with about 1.45bar... my turbo can make 2bar (and has accidentally when we got the electronic boost mapping the wrong way around) however additional boost didn't increase power, we hit a wall.
Boosted LS1 said:
OP, what was your bore clearance again?
I've used Ross pistons for eons in turbocharged cosworth 24v v6 motors without any issues. That said the Mahle alloy is a very good one but when they couldn't supply the US demand the yanks developed their own alloys.
Also, PEC has been mentioned. I've only bought a few zetec parts from them but they were a very pleasing price unlike CP who I think are very expensive. I've not bought from them though. JE are an awful company to do business with as are Omega (who have a good alloy).
Piston to bore clearance was measured at 280 microns, that wasn't in a wear location apparently.I've used Ross pistons for eons in turbocharged cosworth 24v v6 motors without any issues. That said the Mahle alloy is a very good one but when they couldn't supply the US demand the yanks developed their own alloys.
Also, PEC has been mentioned. I've only bought a few zetec parts from them but they were a very pleasing price unlike CP who I think are very expensive. I've not bought from them though. JE are an awful company to do business with as are Omega (who have a good alloy).
Omega pistons are a possibility, however i have to put the standard length noble rods back in. These rods are actually arrow items around 2mm shorter (this is how noble lowered the CR using stock pistons) but are 50 grams heavier than my Mountune Rods.
So the rotating mass would be slightly heavier and the piston geometry slightly compromised over what i had before... Im thinking of using these to build a 'cheap' spare engine as they would be oversize.
What I have done in the last week is manage to source a brand new complete engine, of cause its a stock NA unit so I would need to drill oil squirters in the block and get the heads flowed... and whilst not cheap it was only around £300 more than simply re-sleaving my existing block
As it stands I don't actually have the money to build a full spec engine up as I have spent my entire budget on the Syvec, loom, new gearbox design and thus drive shafts etc.... I hadn't planned on spending £7k on an engine refresh lol.
If I build a spare engine using an old block, it won't make the big numbers my old one does (would do over 600bhp tho), but i will at least get on the road and can then steadily build up the full monty engine over the coming year or so... alternatively the car will be off the road till the big engine is done....
Im undecided at the moment lol
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