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Update to used oil analysis

bbwb
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bbwb Enthusiast

bbwb

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This is an update to a post I made about 6 months ago regarding finding fuel in my oil.  After replacing the high pressure fuel pump, I ran it through the summer and changed oil in October.

This fuel test came back with 4% fuel in the oil.

Dealership is found there are leaking injectors and will be replacing them all as they are not sure which one it is because it is a slight one (fuel pump would always prime when I open the door in the morning),  Parts on order and will get it back at the end of the week.

They said that this could also cause the slight stumble at idle while sitting at the light (this was brought to them when new and got the "couldn't duplicate customer's concern - all is well" line.

Robert

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jrmcswain Enthusiast

jrmcswain

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We're you throwing any codes? Negative values in long term fuel tables? I have a Hennessey Performance Goliath 650 the oil smells like gasoline. Could be normal for forced Induction but still worried about my engine.

 

bbwb Enthusiast

bbwb

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No codes.  Other than a slight stumble at idle, no other symptoms.  

Grumpy Bear Senior Enthusiast

Grumpy Bear

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2 hours ago, Gagliano7 said:

I can smell gas in my oil but it runs perfect and no rise in oil on my dipstick.

 

Two problems with gas in oil that take a while to show. 

 

1.) Even 3 or 4% by GC detection WILL lower the viscosity one SAE grade and accelerates wear. Mainly bore/ring wear but can also attack cam/roller interface. 

 

2.) Gas in oil leaves varnish behind in the hottest parts of the motor. Biggest issue seen first is ring packs sticking. Second is slows heat transfer through the head of the piston. Increases tendency to 'knock'. 

 

Even if you manage to stop the leak and solve out the varnish the damage it caused remains for the life of the motor. 

 

And yes, it will run perfect...until it doesn't. 

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Black02Silverado Senior Enthusiast

Black02Silverado

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20 hours ago, jrmcswain said:

We're you throwing any codes? Negative values in long term fuel tables? I have a Hennessey Performance Goliath 650 the oil smells like gasoline. Could be normal for forced Induction but still worried about my engine.

 

Just curious as to what a used oil analysis would look like on your beast.  Ever think of getting a sample to send in?  I could run it and let you know how well things are inside.

 

 

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bbwb Enthusiast

bbwb

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Well, got it back and it is running SMOOTH for the first time since I got it.  Early on I brought up the slight stumble to the dealer but was told all was ok.  Nope, it was not.

Attached is the used oil analysis that brought the fuel in oil to light.

Oil Analysis.jpg

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Nitrousbird Enthusiast

Nitrousbird

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Blackstone saved me some big money.  My Vette had titanium in the oil - punted it while I could sell it for a profit.  

newdude Senior Enthusiast

newdude

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10 hours ago, bbwb said:

Well, got it back and it is running SMOOTH for the first time since I got it.  Early on I brought up the slight stumble to the dealer but was told all was ok.  Nope, it was not.

Attached is the used oil analysis that brought the fuel in oil to light.

Oil Analysis.jpg

 

 

This test.  Is this pre injector replacement or post injector replacement?

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bbwb Enthusiast

bbwb

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This was pre-high pressure fuel pump around Memorial Day and pre-injector replacement this week.  Will have to get it checked after some miles to see if it really is fixed.

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