My fresh 3.0 (only 3,000 miles after rebuild) is burning about 1 qt.
per 750 miles, using Castrol 20W-50 GTX. This is during rather
hard back road driving, where the car is always up over 4k+ RPM and
often hitting redline. Perhaps this topic has been covered before,
but I could not find "typical" oil consumption figures for hard-
driven V6 engines.
I recently did a total rebuild on this 3.0, both top and bottom end.
It had about 120,000 miles on it before rebuild. I ended up reusing
the original cylinder sleeves, as they measured good as new...the
shop re-honed them and I re-ringed using all Hastings rings. Valve
guides were replaced with Centerline's silicon bronze guides, which
are specially cut at the top to accept their teflon valve seals.
Guides were reamed per Alfa specs and the existing valves were
reused, as they also measured like new. (I think the valves might
have been replaced during an earlier valve job before I bought the
engine.)
At break-in, I made sure to load the engine heavily and varied both
RPM and load for the first 300 miles or so. Also kept max. RPM under
3,500 until I got to 1,000 miles; I carefully followed the standard
rules for break-in.
I notice a brief bit of smoke initially at startup, but ONLY if
the car has been sitting for many weeks. It dissipates quickly and I
do not see any smoke after it has warmed up, even under hard
acceleration and deceleration (I had a friend follow behind me).
This engine runs fantastic! Smooth, powerful, confident...I couldn't
be happier. But I AM concerned about the oil consumption. Is this
a "typical" amount? Perhaps at 3k miles, the rings are not 100%
seated yet, as I opted to reuse the original liners? Does anyone have
a similar experience with a rebuilt engine to share...or comments on
the Hastings rings/Centerline guide + teflon valve seals setup?
Thanks,
Dennis
San Diego, CA
Dennis I have had a very similar experience.Mine is a 2.5.I did a complete rebuild and reused my "within spec" pistons and liners.I rotated the liners 90 deg.In my case I used Total Seal rings.Liners were honed to Total-Seal specs.My engine also runs great - about 20k miles since rebuild,and consumes just about the same amount of oil as yours running Castrol 20/50.I've done extensive testing to figure out where the oil is going with no success and can only conclude that there is enough getting by the rings to give this result.I guess a small amount getting burned continuously doesn't show up as blue smoke.This winter I'm throwing in new pistons ,liners, and rings.Hope your case turns out to be different - give it a few thousand more miles before concluding that it's not going to stop consuming oil.
1986-GTV6
1989-75 Twinspark very sadly sold-remarkable sedan !
2014 Audi Q5 3.0l TDI - torque MONSTER
1989-75 Twinspark very sadly sold-remarkable sedan !
2014 Audi Q5 3.0l TDI - torque MONSTER
Murray: Thanks for the report. Hmmmmm...seems strange that this might occur due to the rehoning of our liners...this is a traditional procedure done over and over on a multitude of engines without adverse effects. Perhaps the honing is an extremely critical process and neither one of us got it quite right. Or...perhaps liner concentricity and wear are a lot more critical than Alfa specs would lead us to believe.
My small puff of smoke at startup...after the car has been unused for a long time...seems to indicate that oil is leaking down past the valve guides. Could it be that one of my new Teflon valve seals has decided to pop off? (I also put seals on the exhaust valves as well.) In a test, I noticed that the teflon seals are a LOT easier to place on...and remove...than the OEM Alfa Viton seals. I kind of wish now that I had gone with the Alfa seals...I'd have some peace of mind. Alfa seals do NOT come off...if you have tried to remove old ones you know what I mean.
Somebody told me Alfa specifies 1 quart / 1,000 miles as acceptable, but I cannot find this documentation anywhere. And if this is for a car that is driven less aggressively, it might be possible that our consumption is in fact near normal. Driving the engine hard WILL increase consumption, as higher RPMs cause that many more cycles for oil to be left on the cyl walls and then get burned off. Bet if I drive the car at 3,500 RPM or below on a highway I will have much less consumption.
Did your consumption reduce over the 20k miles you put on it, or was it 750 miles/qt from the beginning?
An interesting topic, eh...?
-Dennis
My small puff of smoke at startup...after the car has been unused for a long time...seems to indicate that oil is leaking down past the valve guides. Could it be that one of my new Teflon valve seals has decided to pop off? (I also put seals on the exhaust valves as well.) In a test, I noticed that the teflon seals are a LOT easier to place on...and remove...than the OEM Alfa Viton seals. I kind of wish now that I had gone with the Alfa seals...I'd have some peace of mind. Alfa seals do NOT come off...if you have tried to remove old ones you know what I mean.
Somebody told me Alfa specifies 1 quart / 1,000 miles as acceptable, but I cannot find this documentation anywhere. And if this is for a car that is driven less aggressively, it might be possible that our consumption is in fact near normal. Driving the engine hard WILL increase consumption, as higher RPMs cause that many more cycles for oil to be left on the cyl walls and then get burned off. Bet if I drive the car at 3,500 RPM or below on a highway I will have much less consumption.
Did your consumption reduce over the 20k miles you put on it, or was it 750 miles/qt from the beginning?
An interesting topic, eh...?
-Dennis
I rebuilt my 3.0 a few years ago. I put about 3000 miles on it a year. And those are usually for blasting down the freeway, backroads or track events. So when the 3.0 gets driven, it's not for putting around.
Since then the oil consumption has been about 1 qt/ 3000-4000 miles. I had a set of used liners honed, with JE pistons and Total seal rings.
I think 1 qt/2000 miles is ok for a rebuilt engine. But 1 qt/750 miles is not. I read in some Audi forums, that even Audi says it's ok for 1 qt/ 800 miles. I think this is just a kind of a waiver for them, and for manufacturers in general. It seems like they just don't want customers complaining about the oil consumption and claiming defect.
Since then the oil consumption has been about 1 qt/ 3000-4000 miles. I had a set of used liners honed, with JE pistons and Total seal rings.
I think 1 qt/2000 miles is ok for a rebuilt engine. But 1 qt/750 miles is not. I read in some Audi forums, that even Audi says it's ok for 1 qt/ 800 miles. I think this is just a kind of a waiver for them, and for manufacturers in general. It seems like they just don't want customers complaining about the oil consumption and claiming defect.
Hmmm...might be a legal disclaimer, but an admittedly unscientific review of comments on the WWW reveals that oil consumption on V6s is all over the place...and that is both for original factory engines and those that have been rebuilt. I've read reports that vary from a smoking 250 mi/quart (!) to an seemingly impossible 5,000 miles /quart.
I rebuilt my engine carefully, did everything "according to the book," so I wonder what the heck is causing this consumption? Problem is, in order to determine this, one needs to completely tear down the engine anyway, so a complete rebuild becomes the diagnostic method...surely not attractive.
I think I'll put a few more miles on and see if it improves. If not, I'll just live with it, provided it passes smog OK. (It passed with flying colors just 500 miles after the rebuild.) The hassle and expense of another rebuild so soon is not a pleasant thought...especially since the engine runs so great!
Zamani, BTW this 3.0 is what replaced the Milano 2.5 that blew up at Streets of Willow 3 years ago. You remember that? I still appreciate all the help you provided me...
-Dennis
I rebuilt my engine carefully, did everything "according to the book," so I wonder what the heck is causing this consumption? Problem is, in order to determine this, one needs to completely tear down the engine anyway, so a complete rebuild becomes the diagnostic method...surely not attractive.
I think I'll put a few more miles on and see if it improves. If not, I'll just live with it, provided it passes smog OK. (It passed with flying colors just 500 miles after the rebuild.) The hassle and expense of another rebuild so soon is not a pleasant thought...especially since the engine runs so great!
Zamani, BTW this 3.0 is what replaced the Milano 2.5 that blew up at Streets of Willow 3 years ago. You remember that? I still appreciate all the help you provided me...
-Dennis
Hi Dennis,
I haven't been to the Streets of Willow in a very long time. I will try to go to the race school this October. I've been going to the big track only. Hopefully will break 1:40 next time around hehe
One thing my mechanic pointed out to me is to make sure the liner and pistons are absolutely clean. We spent about 1 hour washing the piston and liners with hot soapy water. After each wash, we would use a slightly oily paper towel and rub the liner to see if any dirt are present. One liner took 10 minutes to be thoroughly cleaned. I think some places only wipe it down with WD40 or some oil substance and call it good. How did you deal with the liners?
Also, the head work should be done well. Mine was done by Norman Racing up in Berkeley. I used all original Alfa parts for the head.
As for break in, my mechanic told me, the rings either seat in the first few hundred miles or they don't. I used 10w40 mineral oil for the first 300 miles. Went for lots of up hill drives. Then 20w50 Castrol Syntec. So far so good.
Oh well the 12V days are numbered, I just purchased my first 24V motor (due to peer pressure).
I haven't been to the Streets of Willow in a very long time. I will try to go to the race school this October. I've been going to the big track only. Hopefully will break 1:40 next time around hehe
One thing my mechanic pointed out to me is to make sure the liner and pistons are absolutely clean. We spent about 1 hour washing the piston and liners with hot soapy water. After each wash, we would use a slightly oily paper towel and rub the liner to see if any dirt are present. One liner took 10 minutes to be thoroughly cleaned. I think some places only wipe it down with WD40 or some oil substance and call it good. How did you deal with the liners?
Also, the head work should be done well. Mine was done by Norman Racing up in Berkeley. I used all original Alfa parts for the head.
As for break in, my mechanic told me, the rings either seat in the first few hundred miles or they don't. I used 10w40 mineral oil for the first 300 miles. Went for lots of up hill drives. Then 20w50 Castrol Syntec. So far so good.
Oh well the 12V days are numbered, I just purchased my first 24V motor (due to peer pressure).
in my rebuild, I used new liners, pistons, rings all stock supply and had a little smoke first few hundred miles, then no real oil loss since (~2000+) miles. Compression good all around. I have not even added oil even after original rebuild and left side head change. It does smoke very minimally for about 5 seconds on start-up but I suspect that is from valve guide leakdown.
I think the consumption you describe is due to oil ring liner gap....
I think the consumption you describe is due to oil ring liner gap....
Zamani: I did not apply the meticulous care that you did to the liners. They came back from the local shop looking pretty clean, but perhaps on a microscopic level they were not. I remember putting a rag w/WD-40 through them and did not recall any residue.
As the honing and other machine work was not done by an Alfa specialist, it is quite possible that the honing was not done to proper specs (not round enough, improper depth, grit or angle), or that the valve guide reaming was too large, allowing oil to be sucked down past the guide. Also, I speculate that perhaps one of my guides has lost the Teflon seal...as they are rather easy to dislodge in my opinion.
If I were to do this over again, I would use Alfa OEM valve seals and have a shop like Jon Norman measure everyting and do the machine work. Live and learn.
I did some research into oil consumption over at BMW and certain models have a similar disclaimer. It apperas that the M5s are notorious for burning 1 qt / 700 - 800 miles! Again, BMW says that "this is normal" and advises owners to drive the car a full 10,000 miles before asking for warrantee repairs. And this is for new engines from a VERY competent engine manufacturer...BMW. Hmmmm?
I think X-Rad is probably right. Since I have reused liners that are surely a tiny bit oval (but within spec), and only 3,000 miles on the rebuild, it is quite possible that my "problem" might get better in time. Yes, all engines develop oval liners but the rings have GRADUALLY assumed that same oval shape through use, maintaining good seal. In my case, I have perfectly round rings attempting to seal to a very slight oval...so a full circle seal might take some time...if ever!
Starting with new liners helps ensure a good oil seal from day one, as they are perfectly round to match the rings. $800 more for liners seemed like a lot to spend, since my old liners were "in spec" and again in retrospect...live and learn. I should have spent the bucks perhaps...
-Dennis
As the honing and other machine work was not done by an Alfa specialist, it is quite possible that the honing was not done to proper specs (not round enough, improper depth, grit or angle), or that the valve guide reaming was too large, allowing oil to be sucked down past the guide. Also, I speculate that perhaps one of my guides has lost the Teflon seal...as they are rather easy to dislodge in my opinion.
If I were to do this over again, I would use Alfa OEM valve seals and have a shop like Jon Norman measure everyting and do the machine work. Live and learn.
I did some research into oil consumption over at BMW and certain models have a similar disclaimer. It apperas that the M5s are notorious for burning 1 qt / 700 - 800 miles! Again, BMW says that "this is normal" and advises owners to drive the car a full 10,000 miles before asking for warrantee repairs. And this is for new engines from a VERY competent engine manufacturer...BMW. Hmmmm?
I think X-Rad is probably right. Since I have reused liners that are surely a tiny bit oval (but within spec), and only 3,000 miles on the rebuild, it is quite possible that my "problem" might get better in time. Yes, all engines develop oval liners but the rings have GRADUALLY assumed that same oval shape through use, maintaining good seal. In my case, I have perfectly round rings attempting to seal to a very slight oval...so a full circle seal might take some time...if ever!
Starting with new liners helps ensure a good oil seal from day one, as they are perfectly round to match the rings. $800 more for liners seemed like a lot to spend, since my old liners were "in spec" and again in retrospect...live and learn. I should have spent the bucks perhaps...
-Dennis
Dennis,
At this point, maybe you can try checking or replacing the valve seals. Then use Castrol Syntec 20w50 to see if that can help. Maybe after these things, you can go up to 1300 miles per quart. That should be enough for a few years.
BTW, when installing the liner, did you use excessive amount of assembly lube?
When my mechanic and I installed the pistons, he just sprayed a little bit of thin (maybe 10w30) motor oil. He said if you use something too thick and put too much of it, the rings won't seat.
But all is not lost of course. If you think this isn't working out for you in a few years order slightly oversized forged pistons and bore out the liner a little, maybe 0.5mm overbore. I think they cost about $1100 for a set but are considerably lighter than stock 12V pistons.
At this point, maybe you can try checking or replacing the valve seals. Then use Castrol Syntec 20w50 to see if that can help. Maybe after these things, you can go up to 1300 miles per quart. That should be enough for a few years.
BTW, when installing the liner, did you use excessive amount of assembly lube?
When my mechanic and I installed the pistons, he just sprayed a little bit of thin (maybe 10w30) motor oil. He said if you use something too thick and put too much of it, the rings won't seat.
But all is not lost of course. If you think this isn't working out for you in a few years order slightly oversized forged pistons and bore out the liner a little, maybe 0.5mm overbore. I think they cost about $1100 for a set but are considerably lighter than stock 12V pistons.
Zamani:
Thanks for the tips. I dont recall exactly, but I believe I simply wiped the cylinder with a rag with a very small amout of SAE 30 on it, then wiped it off the liner with a dry rag. My opinion is that a bit of folklore exists regarding assembly procedures. Consider this, for 50 years the standard method for rebuild was to completely submerge the pistons and rings in SAE 30, let most drip off and then assemble! The rings somehow managed to seat in the presence of this gross amount of oil, which gets 99.9% burned off on the first ignition anyway. While I dont advocate this old school procedure, I do think too much superstition exists.
In my case, I think it is a simple matter of the cylinder walls being a bit out of round and/or the honing not being done right. It might take some more time for the Hastings to take a full set. Let's hope so.
Unfortunately, the valve guides sold by Centerline are milled at the top to accept the special teflon seals...I do not think they will also accept Alfa OEM seals, but I can ask. I shy away from using Syntec now, as this will retard the chance of any further break-in, my best hope to get the oil con down. If I could get 1,000 or 1,500 miles/qt I would consider this a success and be done with this issue. Anyway, I currently find myself in the fine company of many M5 oil eaters!!!
Maybe I could just buy your 12V when you drop the 24V in! As for my car, I will eventually go Megasquirt, take the AFM out and do a better exhaust system. (Any advice?) This is as exotic (and as powerful) as I want to go. Other Alfa fish to fry.
Since we are on the topic of big power, I have a '60 Giulietta Spider Veloce that is crying for restoration. Now, you want to talk about massive power...go and drive a 1300!
You heard from Chip lately? He sold the 24V and dropped outta sight...
Cheers!
Dennis
Thanks for the tips. I dont recall exactly, but I believe I simply wiped the cylinder with a rag with a very small amout of SAE 30 on it, then wiped it off the liner with a dry rag. My opinion is that a bit of folklore exists regarding assembly procedures. Consider this, for 50 years the standard method for rebuild was to completely submerge the pistons and rings in SAE 30, let most drip off and then assemble! The rings somehow managed to seat in the presence of this gross amount of oil, which gets 99.9% burned off on the first ignition anyway. While I dont advocate this old school procedure, I do think too much superstition exists.
In my case, I think it is a simple matter of the cylinder walls being a bit out of round and/or the honing not being done right. It might take some more time for the Hastings to take a full set. Let's hope so.
Unfortunately, the valve guides sold by Centerline are milled at the top to accept the special teflon seals...I do not think they will also accept Alfa OEM seals, but I can ask. I shy away from using Syntec now, as this will retard the chance of any further break-in, my best hope to get the oil con down. If I could get 1,000 or 1,500 miles/qt I would consider this a success and be done with this issue. Anyway, I currently find myself in the fine company of many M5 oil eaters!!!
Maybe I could just buy your 12V when you drop the 24V in! As for my car, I will eventually go Megasquirt, take the AFM out and do a better exhaust system. (Any advice?) This is as exotic (and as powerful) as I want to go. Other Alfa fish to fry.
Since we are on the topic of big power, I have a '60 Giulietta Spider Veloce that is crying for restoration. Now, you want to talk about massive power...go and drive a 1300!
You heard from Chip lately? He sold the 24V and dropped outta sight...
Cheers!
Dennis
Zamani: I just realized I had been mistaken about you at Streets of Willow 3 years ago. It was your brother Nizam whom witnessed my 2.5 detonate on the track and helped me troubleshoot it. Turned out to be a sticky valve @ 6,500 RPM that hit piston and spewed valve shards through the heads. Destroyed the entire engine...
-Dennis
-Dennis
Zamani: I just realized I had been mistaken about you at Streets of Willow 3 years ago. It was your brother Nizam whom witnessed my 2.5 detonate on the track and helped me troubleshoot it. Turned out to be a sticky valve @ 6,500 RPM that hit piston and spewed valve shards through the heads. Destroyed the entire engine...
-Dennis
-Dennis