-Spooky-

Went to have a clean of the engine bay with the manifold off today and i noticed that one of the valves had a yellow residue round it.

Please see the picture of the valve below. This is the only valve with the yellow residue, all the rest are clean.

It is in position 3 in the picture below.






Is this normal? Is this a sign of something sinister lurking? *panic hat on*

APIDavid

iTrader: (4)

Yellow colour residue in the combustion / valves area is usually due to using octane booster.

That may be all that it is.

David APi

Agents for:
Simtek, the most exciting new Ecu for years
Buddy Club exhausts
Scoobysportexhausts
Eibach suspension
AP Racing brakes and clutches
And of course; the well known APi Performance Exedy organic clutch

www.apiengines.com

01926 614333

-Spooky-

I've never used octain booster Dave, only V-power...

APIDavid

iTrader: (4)

Aah well, it won't be that then..............

It may be just one of those things. Keep an eye on temperature and coolant use. Just in case it is a sign of coolant into the cylinder and being burnt.
BUT, if the motor is running smoothly, with no misfires, I wouldn't fuss too much about it.

David

Agents for:
Simtek, the most exciting new Ecu for years
Buddy Club exhausts
Scoobysportexhausts
Eibach suspension
AP Racing brakes and clutches
And of course; the well known APi Performance Exedy organic clutch

www.apiengines.com

01926 614333

-Spooky-

Someone mentioned it could be a head gasket blowing? would you disagree?

APIDavid

iTrader: (4)

Only by one valve? unlikely in my opinion. AND the engine would be shaking all over the engine bay if it is running rough at all. If you have a silky smooth tickover, it ain't that. Silky smooth as a flat four ever is......

Head gasket is a possibility, but unless you have other problems with the running of it, I would discount the idea. Loss/use of coolant ? That'd be a giveaway.

David

-Spooky-

as far as i am aware there has been no loss of coolant, and tickover is solid at 0.7k so i don't think there is a problem there?

Is there any point in me doing a compression test?

JohnD

iTrader: (5)

I've noticed a slight orange discoloration on the plugs when using V-power.

JohnD

-Spooky-

on all plugs?

dunx

iTrader: (3)

My plugs were a strange brown colour ( VPower + booster )

HTH

DunxC

-Spooky-

bump

-Spooky-

Its been sugested that it's simply residue of old petrol . and that if you turn the engine off with the valve in a particular cylinder fully closed and then a bit of petrol gets down there for any reason, it can do this?

Jolly Green Monster

iTrader: (4)

I think you are worrying about nothing..

JohnD

iTrader: (5)

The valves look nice and clean. (Ah - the wonders of modern fuel and oils!) what's the mileage?

JohnD

-Spooky-

Thanks John...

its a P1 on about 53k at the moment, been on the road since april 2001...

i thought they looked pretty clean, but never seen anyone elses so thought it was just normal lol

APIDavid

iTrader: (4)

Inlet valves usually are clean, it is the exhausts that get all crappy and gummy. Doing a compression test is loads of fun for all the family on a Subaru.

Don't think I'd bother, given that nothing is suggesting a compression problem and how much hassle it is to do the test.

David APi

-Spooky-

Thanks David and co, all your input was gratefully received…