Fuel/Engine Problems
Discussion
Hi
I'm fairly new to the forum and in need of some advice/assistance.
I purchased a Subaru P1 aout a year ago, shortly after a one of the bottom end bearings failed. Several thousand pounds later and only 7000 miles the same thing has happened again.
The garage which undertook the original work issue a subaru waranty on their work. The problem is the garage have come back saying that i have either put the wrong fuel in or that the fuel pump has failed which has damaged one of the bearings? I have only ever used high octane fuel. 99 ron normally however 97 or 98 where i cannot get the 99. Consequently the fuel pump is the only element which wasn't changed by the garage during the original engine rebuild everything else including intercooler was.
Has anyone else had such an experience with their engine being damaged by the fuel pump? or alternatively has anyone else had a similar problem with their garage?
any advice welcome
Thanks
I'm fairly new to the forum and in need of some advice/assistance.
I purchased a Subaru P1 aout a year ago, shortly after a one of the bottom end bearings failed. Several thousand pounds later and only 7000 miles the same thing has happened again.
The garage which undertook the original work issue a subaru waranty on their work. The problem is the garage have come back saying that i have either put the wrong fuel in or that the fuel pump has failed which has damaged one of the bearings? I have only ever used high octane fuel. 99 ron normally however 97 or 98 where i cannot get the 99. Consequently the fuel pump is the only element which wasn't changed by the garage during the original engine rebuild everything else including intercooler was.
Has anyone else had such an experience with their engine being damaged by the fuel pump? or alternatively has anyone else had a similar problem with their garage?
any advice welcome
Thanks
ksx.Err yes they do actualy.
Detonation from the mixture going lean due to a failing fuel pump or from a below spec effective octane rating can easily lead to big end damage.
The sharp and massive increases in combustion chamber pressure during detonation are transmitted through the piston crown, down the rod and in extreme cases can break the oil film over the bearing and as a result cause big end bearing failure via metal - metal contact between bearing and crank.
Detonation from the mixture going lean due to a failing fuel pump or from a below spec effective octane rating can easily lead to big end damage.
The sharp and massive increases in combustion chamber pressure during detonation are transmitted through the piston crown, down the rod and in extreme cases can break the oil film over the bearing and as a result cause big end bearing failure via metal - metal contact between bearing and crank.
Icarus_ said:
Err yes they do actualy.
Detonation from the mixture going lean due to a failing fuel pump or from a below spec effective octane rating can easily lead to big end damage.
The sharp and massive increases in combustion chamber pressure during detonation are transmitted through the piston crown, down the rod and in extreme cases can break the oil film over the bearing and as a result cause big end bearing failure via metal - metal contact between bearing and crank.
Point taken but.....Detonation from the mixture going lean due to a failing fuel pump or from a below spec effective octane rating can easily lead to big end damage.
The sharp and massive increases in combustion chamber pressure during detonation are transmitted through the piston crown, down the rod and in extreme cases can break the oil film over the bearing and as a result cause big end bearing failure via metal - metal contact between bearing and crank.
Would be pretty freaky for it to be the same bearing and only one.
Would also expect the garage to come back and say they had found detonation evidence on the plugs and pistons.
The garage are trying to squirm out of resolving their problem. Why would they suggest wrong fuel or pump failure when it is clearly within their power to test the pump.
Steve
607 said:
Hi
I'm fairly new to the forum and in need of some advice/assistance.
I purchased a Subaru P1 aout a year ago, shortly after a one of the bottom end bearings failed. Several thousand pounds later and only 7000 miles the same thing has happened again.
The garage which undertook the original work issue a subaru waranty on their work. The problem is the garage have come back saying that i have either put the wrong fuel in or that the fuel pump has failed which has damaged one of the bearings? I have only ever used high octane fuel. 99 ron normally however 97 or 98 where i cannot get the 99. Consequently the fuel pump is the only element which wasn't changed by the garage during the original engine rebuild everything else including intercooler was.
Has anyone else had such an experience with their engine being damaged by the fuel pump? or alternatively has anyone else had a similar problem with their garage?
any advice welcome
Thanks
What did the original rebuild entail ( be specific ), and are they a reputable garage with competent mechanics ?I'm fairly new to the forum and in need of some advice/assistance.
I purchased a Subaru P1 aout a year ago, shortly after a one of the bottom end bearings failed. Several thousand pounds later and only 7000 miles the same thing has happened again.
The garage which undertook the original work issue a subaru waranty on their work. The problem is the garage have come back saying that i have either put the wrong fuel in or that the fuel pump has failed which has damaged one of the bearings? I have only ever used high octane fuel. 99 ron normally however 97 or 98 where i cannot get the 99. Consequently the fuel pump is the only element which wasn't changed by the garage during the original engine rebuild everything else including intercooler was.
Has anyone else had such an experience with their engine being damaged by the fuel pump? or alternatively has anyone else had a similar problem with their garage?
any advice welcome
Thanks
What oil are you using, and what sort of usage does the car see, and how often are oil changes ( yes I know its only 7000 miles )
Edited by stevieturbo on Thursday 9th April 18:59
Rebuild included new bottom end,uprated crank, pistons, oil pump, modine, intercooler, and sump.
Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
The mechanic is now saying that 97ron fuel will knock the bottom end out, could this be correct given that there is a possible +/- 3-4% margin in the octane level of the fuel?
I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
If i wanted an independent inspection/assessment of the engine doing what qualifications should i be looking for in the mechanic and does anyone know where to find one?
Cheers folks
Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
The mechanic is now saying that 97ron fuel will knock the bottom end out, could this be correct given that there is a possible +/- 3-4% margin in the octane level of the fuel?
I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
If i wanted an independent inspection/assessment of the engine doing what qualifications should i be looking for in the mechanic and does anyone know where to find one?
Cheers folks
607 said:
Rebuild included new bottom end,uprated crank, pistons, oil pump, modine, intercooler, and sump.
Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
The mechanic is now saying that 97ron fuel will knock the bottom end out, could this be correct given that there is a possible +/- 3-4% margin in the octane level of the fuel?
I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
If i wanted an independent inspection/assessment of the engine doing what qualifications should i be looking for in the mechanic and does anyone know where to find one?
Cheers folks
If you have problems relating to the use of fuel then the head and plugs will be showing signs of detonation and be a total mess.Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
The mechanic is now saying that 97ron fuel will knock the bottom end out, could this be correct given that there is a possible +/- 3-4% margin in the octane level of the fuel?
I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
If i wanted an independent inspection/assessment of the engine doing what qualifications should i be looking for in the mechanic and does anyone know where to find one?
Cheers folks
Bearing failure in my experience is highly unlikely due to the above condition. You normally get it when you have a lubricity issue (diluted oil, wrong oil) or a supply problem (blocked passage) or contaminants in oil (core sand breaking loose).
If you're going to get an inspection done then you are basically saying you're going to go to court and fight this. You are not going to fight this with a mechanic, you need a genuine expert. So that would mean an Engineering report from a company with credibility, like Ricardo or Prodrive, or of a respected tuner who deals with Subarus like Graham Goode.
Personally I think you are going to waste a great deal of money doing this and get nowhere. Rebuild the engine and sell the car to an enthusiast. Move on and buy something reliable.
607 said:
Rebuild included new bottom end,uprated crank, pistons, oil pump, modine, intercooler, and sump.
Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
Std cranks are quite fine, although the later sti cranks are better. Why new pistons ?Oil used is shell 10-40
I had the 1000 mile service after the rebuild then another at 6000 miles at christmas where i had the rad changed.
The mapping was done by the same garage at the time of the 1000mile service, they are an approved subaru waranty garage.
Modine ???
Personally I'd only ever reccomend Mobil 1 motorsport 15/50, or Millers oil. But others have different ideas.
Any inspection would need to ensure the crank etc was new. What type of oil pump ? Most people with any sense, use an uprated oil pump, although it isnt essential.
607 said:
The mechanic is now saying that 97ron fuel will knock the bottom end out, could this be correct given that there is a possible +/- 3-4% margin in the octane level of the fuel?
I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
If it was mapped on 97RON fuel, as you seem to suggest it was, then it should be 100% safe on that fuel. TBH, Ive never heard of official Subaru dealers offering re-maps of any sort. Is this place a Subaru dealer ? or what do they actually do ? I'm at a loss as to what to do next the rebuild and mapping was approx 5k where i was told the engine would be bomb proof.
607 said:
If i wanted an independent inspection/assessment of the engine doing what qualifications should i be looking for in the mechanic and does anyone know where to find one?
Cheers folks
Hard to say, but as Gavin suggest, an independant recognised Subaru specialist would be one option.Cheers folks
But unfortunately, big ends are a problem on Subarus, but for it to have happpened at such a low milage after a rebuild, could put into question either the workmanship, or parts used. Where any other non standard parts fitted ? clutch ? flywheel ?
If the garage are blaming fuel as you imply....well, you also say its the same garage who remapped your car to suit this fuel.
But if it was in any way detonation related...I'd say your pistons would be toast long before the big ends.
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