big end
#1
hi,i wondered if anyone could help??..im a proud owner of a scooby..just a few days ago whilst going on night out i noticed a knocking sound coming from the engine,then all of a sudden the engine started losing power having just beaten an evo on the m6 my ego was bruised..well anyway the next day i got a mechanic out to have a look at it...heres the bad news...the big end has gone!!!...why???...how come????
#2
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Due to poor cooling, wrong grade oil, oil too old, due to det, oil pump faulty, fuel pump faulty, MAF failure, user error..
Could be many many reasons..
Why not wait until it is stripped to find out..
JGM
Could be many many reasons..
Why not wait until it is stripped to find out..
JGM
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#11
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I just had my 22500 service on a MY01 bugeye and the guys at the dealership where it was serviced insisted it had magnatec and that Subaru reccommended it..
got me worried now, mite have to do an oil change
Phil
got me worried now, mite have to do an oil change
Phil
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I have not used them only observed there website so I cannot comment on whether they are good or not but www.midland-impreza.com do engines for £1400 recon and fitted I believe.
If you use them can you let me know how you get on as I would like to know if they are any good..
Failing that email Rally Colin.. who posts on here...
colin_minton@hotmail.com
JGM
If you use them can you let me know how you get on as I would like to know if they are any good..
Failing that email Rally Colin.. who posts on here...
colin_minton@hotmail.com
JGM
#14
Ther are loads who have, one here ... Castrol RS10-60, Motul M300v 15-50, Mobil Motorsport 15-50 or even Shell Ultra Plus 5-30 are all better than the Magnetec ... all imho of course. The Shell not recommended for uprated use but ok for std cars.
Once repaired use mineral oil for the first 1000 miles then a good semi-synthetic up to 7500 then change to one of the above, suggest Shell Ultra 10-40 as a good semi synthetic.
Thats what I do, and have done with no problems and all my engines have been run at an enhanced level.
however you pays your money as they say.
bob
Once repaired use mineral oil for the first 1000 miles then a good semi-synthetic up to 7500 then change to one of the above, suggest Shell Ultra 10-40 as a good semi synthetic.
Thats what I do, and have done with no problems and all my engines have been run at an enhanced level.
however you pays your money as they say.
bob
#15
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In the Castrol recommended Lubricant charts...they specify GTX Magnatec
If it wasn't suitable why would castrol reccomend it over their better grades like SLX or RS??
Failure is more likely due to bad running/fueling causing detonation rather than the oil.
[Edited by ALi-B - 1/15/2004 11:26:10 PM]
If it wasn't suitable why would castrol reccomend it over their better grades like SLX or RS??
Failure is more likely due to bad running/fueling causing detonation rather than the oil.
[Edited by ALi-B - 1/15/2004 11:26:10 PM]
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LOL..
Now why would a manufacture recommend one of it's own products?
PMSL..
They just match the manufactures spec, they have not drive a scoob thousands of miles with magnetec in it..
It is not good in the Scoob engine.. full stop..
JGM
Now why would a manufacture recommend one of it's own products?
PMSL..
They just match the manufactures spec, they have not drive a scoob thousands of miles with magnetec in it..
It is not good in the Scoob engine.. full stop..
JGM
#17
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Durrr It's a Castrol Lubricants chart!
Well why don't they recommend their MORE EXPENSIVE castrol RS or SLX??? (read my post in future )
Mind, on some of their older charts before SLX came out, some vehicles were down as to "Use Only Mobil 1". Yes, on a Castrol data chart...go figure!
[Edited by ALi-B - 1/16/2004 1:26:56 PM]
Well why don't they recommend their MORE EXPENSIVE castrol RS or SLX??? (read my post in future )
Mind, on some of their older charts before SLX came out, some vehicles were down as to "Use Only Mobil 1". Yes, on a Castrol data chart...go figure!
[Edited by ALi-B - 1/16/2004 1:26:56 PM]
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Check you have water in the header tank etc My header tank emptied itself while I was driving I had a fast run at 3 in the morning and the Big ends went....... Poor cooling killed my car!
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Ali-G,
I wouldn't put Magnetec in a turbo engine.. full stop..
I don't care if Castrol recommend cooking oil instead (yes an insult to Mobil 1) after removing it from a Turbo car and seeing the state of it compared to other oils after similar mileage between changes it was plain to see imho that it was not designed to with stand the heat produced in a Turbo car..
I take offence to you telling me to read your post in future when I did read it and STILL it did not change my opinion and just because I didn't agree with you, you assume I didn't read it.
If you know what Bob does for a living you might actually understand that he does have a bit more knowledge on this subject than most, and I have seen it first hand and would not use Magnetec in a turbo engine.
You don't agree.. fail enough it is a free country but no need to slate what has been said by other people just because you have a chart infront of you that Castrol have themselves produced to sell there oils and specced each car just by looking at the manufactures spec and not tried them in the car.
JGM
I wouldn't put Magnetec in a turbo engine.. full stop..
I don't care if Castrol recommend cooking oil instead (yes an insult to Mobil 1) after removing it from a Turbo car and seeing the state of it compared to other oils after similar mileage between changes it was plain to see imho that it was not designed to with stand the heat produced in a Turbo car..
I take offence to you telling me to read your post in future when I did read it and STILL it did not change my opinion and just because I didn't agree with you, you assume I didn't read it.
If you know what Bob does for a living you might actually understand that he does have a bit more knowledge on this subject than most, and I have seen it first hand and would not use Magnetec in a turbo engine.
You don't agree.. fail enough it is a free country but no need to slate what has been said by other people just because you have a chart infront of you that Castrol have themselves produced to sell there oils and specced each car just by looking at the manufactures spec and not tried them in the car.
JGM
#20
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In reference to asking to read my posts: you wrote
I previous wrote:
Perhaps you now understand the point I was getting at. I not saying you should put it you car or not.
Still does not answer my question as to WHY Castrol don't recommend Castrol RS instead???
Lawsuit against Castrol anyone????
[Edited by ALi-B - 1/16/2004 5:05:09 PM]
Now why would a manufacture recommend one of it's own products?
why would castrol reccomend it over their better grades like SLX or RS??
Still does not answer my question as to WHY Castrol don't recommend Castrol RS instead???
Lawsuit against Castrol anyone????
[Edited by ALi-B - 1/16/2004 5:05:09 PM]
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Because Castrol match it to the spec given by Subaru which is ****e.. imho.. which is worrying really.. the car manufacturer recommends an oil which is not up to the job.
All this stems from Subaru spec of the oil I think.
JGM
All this stems from Subaru spec of the oil I think.
JGM
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Subaru prescribes oil of a certain viscosity, and that's 5W40 or 10 W40. The oil that Castrol has in it's programme that fulfills this spec is the Magnatec.
Done.
Does not mean by any means that that's the best Castrol oil for a Scooby.
I run Castrol RS 10W60 in my track car, that stuff is holy! Never seen an engine that clean inside with this oil.
Done.
Does not mean by any means that that's the best Castrol oil for a Scooby.
I run Castrol RS 10W60 in my track car, that stuff is holy! Never seen an engine that clean inside with this oil.
#23
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It's not just viscosities though...that is only a very small part of oils...but heres when things get interesting
Magnatec has an APi rating of: SJ
and ACEA rating of : A3
Subaru for the Impreza Turbo (classic) specify: API of SG
and ACEA of A1,A2 or A3
Now SJ exceeds SG and Magnatec also conforms to ACEA ratings too
that being A3: Stable, stay-in-grade oil intended for use in high performance gasoline engines and / or for extended drain
intervals where specified by the engine manufacturer, and / or for year-round use of low viscosity oils, and/or for severe
operating conditions as defined by the engine manufacturer.
Perhaps it's not Castrol's fault - just Subaru for specifying sh1te oil
Now if you go thrashing around alot or go on track days, or have tweeked the engine. Then ANY "recommended" oil by either car or oil manufacturer will be no good!!
Now if Magnatec were used in a car that was used heavily thrashed or tracked (or even driven 1 mile a day) and normal service schedules then I'd expect to see it degrade and cause problems. unless it was changed more regulary under the service clause "Extreme Operating Conditions".
Am I stating the obvious?
[Edited by ALi-B - 1/16/2004 7:37:42 PM]
Magnatec has an APi rating of: SJ
and ACEA rating of : A3
Subaru for the Impreza Turbo (classic) specify: API of SG
and ACEA of A1,A2 or A3
Now SJ exceeds SG and Magnatec also conforms to ACEA ratings too
that being A3: Stable, stay-in-grade oil intended for use in high performance gasoline engines and / or for extended drain
intervals where specified by the engine manufacturer, and / or for year-round use of low viscosity oils, and/or for severe
operating conditions as defined by the engine manufacturer.
Perhaps it's not Castrol's fault - just Subaru for specifying sh1te oil
Now if you go thrashing around alot or go on track days, or have tweeked the engine. Then ANY "recommended" oil by either car or oil manufacturer will be no good!!
Now if Magnatec were used in a car that was used heavily thrashed or tracked (or even driven 1 mile a day) and normal service schedules then I'd expect to see it degrade and cause problems. unless it was changed more regulary under the service clause "Extreme Operating Conditions".
Am I stating the obvious?
[Edited by ALi-B - 1/16/2004 7:37:42 PM]
#24
The main thing is viscocity index, you will find that Magnetec will not withstand the temps that the turbo subjects it to, it then carburises.
I ran Shell Helix Ultraplus in my wagon for over a year, it maintained oil pressure etc and didn't carburise. Changing to Motul bumped pressure at idle by a full bar though, and ensured I got 6 bar by 1800 rpm, that never happened with the helix, pressure would be dropping below 2800 rpm.
Subaru also tell you in the manual that what they recommend is not suitable for heavy use and suggest alternative grades.
Those that push there cars in any way MUST use top oils and those mentioned are known to stand up. Even so oil and filter changes mid service are almost mandatory under those circumstances.
Lets take a track day regime, I would change oil and filter b4 going, keep a close eye on levels etc there and then change oil and filter again straight afterwards.
cheers
bob
I ran Shell Helix Ultraplus in my wagon for over a year, it maintained oil pressure etc and didn't carburise. Changing to Motul bumped pressure at idle by a full bar though, and ensured I got 6 bar by 1800 rpm, that never happened with the helix, pressure would be dropping below 2800 rpm.
Subaru also tell you in the manual that what they recommend is not suitable for heavy use and suggest alternative grades.
Those that push there cars in any way MUST use top oils and those mentioned are known to stand up. Even so oil and filter changes mid service are almost mandatory under those circumstances.
Lets take a track day regime, I would change oil and filter b4 going, keep a close eye on levels etc there and then change oil and filter again straight afterwards.
cheers
bob
#25
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Yep IIRC it's 10w40 for normal use (as per magnatec)
And a hot temp rating of 50w for extreme operating conditions (such as 20w50 or 10w50 etc)
2nd consideration with oil breaking down at high temps, is WHY the oil is reaching such a high temperature. Then you have the usual factors comming into play... Fueling, ignition and cooling.
And then for modified/raced engines you need to question weather the current oil/water cooler is up to the job, oil pump capacity, sump capacity, thermostat temp rating. It just goes on and on. Stop the oil getting too hot and it wouldn't boil in the first place. Using a high temp oil is just the quick and easy fix to the problem IMHO
[Edited by ALi-B - 1/16/2004 8:18:13 PM]
And a hot temp rating of 50w for extreme operating conditions (such as 20w50 or 10w50 etc)
2nd consideration with oil breaking down at high temps, is WHY the oil is reaching such a high temperature. Then you have the usual factors comming into play... Fueling, ignition and cooling.
And then for modified/raced engines you need to question weather the current oil/water cooler is up to the job, oil pump capacity, sump capacity, thermostat temp rating. It just goes on and on. Stop the oil getting too hot and it wouldn't boil in the first place. Using a high temp oil is just the quick and easy fix to the problem IMHO
[Edited by ALi-B - 1/16/2004 8:18:13 PM]
#26
There's nothing much too wrong with whats in place to look after the cooling, external oil cooler helps but the problem is as the oil passes through the turbo not as it runs around the engine ... no oil cooler will stop inadequate oil for these cars carburising will it ... or are we missing something. Sorry I don't believe we are, this has been done to death before, there are many large threads on the subject as the search will show, all draw the same conclusion, inadequate oil equals dead engine and its been unfortunately demonstrated all too often. Oh and if the big ends stay in one piece inevitably the turbo bearings won't, then you lose that from damaged oil seals.
On a previous turbo car (not subaru) I would see oil temps in the 120 deg region as "normal" with 140 on the track, I used Mobil 0-40 for 70,000 miles running hybrid turbo and all the goodies, never had a problem. Thats not suited to the Impreza but ... it was high quality oil, those that ran lower quality oils tended to suffer.
That's not the whole story when it comes to big end failure though, just part (a big part mind you).
edit to add that 5-30 is the stated Subaru general oil visc range for "normal" use (in GC8's at least) which is why Mobil still make that oil as well as the 0-40, the note in the workshop manual says "5-30 is not recommended for sustained high speed driving" btw and suggests a 10-40.
bob
[Edited by Bob Rawle - 1/16/2004 10:03:50 PM]
On a previous turbo car (not subaru) I would see oil temps in the 120 deg region as "normal" with 140 on the track, I used Mobil 0-40 for 70,000 miles running hybrid turbo and all the goodies, never had a problem. Thats not suited to the Impreza but ... it was high quality oil, those that ran lower quality oils tended to suffer.
That's not the whole story when it comes to big end failure though, just part (a big part mind you).
edit to add that 5-30 is the stated Subaru general oil visc range for "normal" use (in GC8's at least) which is why Mobil still make that oil as well as the 0-40, the note in the workshop manual says "5-30 is not recommended for sustained high speed driving" btw and suggests a 10-40.
bob
[Edited by Bob Rawle - 1/16/2004 10:03:50 PM]
#30
thanks for your feed back i will definatly do my homework about what grade oil i put in the car...will let you know how i get on!.. goin away for 2wks so i will be in touch when i get back!...