Piston wash patterns

[huskyboy]

Do popups disrupt transfer flow/scavenging?

 

[MustangMike]

Probably depends on how your transfers are angled!!! (Actually, I have no idea!!!)

Maybe a bridge port will help it jump over!

 

[Nutball]

Do popups disrupt transfer flow/scavenging?

I haven't noticed a difference in wash pattern.

 

[huskyboy]

I haven't noticed a difference in wash pattern.

Have you tested a difference in power vs a flat top with the same compression?

 

[Nutball]

I have not, just noticed that the wash pattern doesn't always change with a popup, whatever that means since I don't understand piston wash very well.

 

[Ronie]

Older 550 wash pattern.

 

[huskyboy]

Last picture of a wash pattern I have for now. 7310 dolmar wash.

 

[deye223]

Older 550 wash pattern.

View attachment 299733

No I don't want to turn this into a oil thread but what oil have you been running in that the saw .

 

[MustangMike]

That 7310 must really jump as it has that classic "Froggie" wash pattern!

 

[Ronie]

No I don't want to turn this into a oil thread but what oil have you been running in that the saw .

I got the saw a couple of months ago and have been running Blackmax from Walmart, maybe five or six tanks, I don't know what the guy before me ran in it.

 

[deye223]

I got the saw a couple of months ago and have been running Blackmax from Walmart, maybe five or six tanks, I don't know what the guy before me ran in it.

View attachment 299832

I only have my phone to look at the picture is the carbon thick and caked on or just a thin glaze

 

[Ronie]

I only have my phone to look at the picture is the carbon thick and caked on or just a thin glaze

It's thin

 

[Ronie]

I only have my phone to look at the picture is the carbon thick and caked on or just a thin glaze

I made the pic bigger and brighter.

 

[deye223]

I made the pic bigger and brighter.

View attachment 299840

Arrrr that looks bettera.

 

[huskyboy]

I made the pic bigger and brighter.

View attachment 299840

How flat are the upper transfer roofs? Kinda hard to see any wash.

 

[Ronie]

How flat are the upper transfer roofs? Kinda hard to see any wash.

Very flat.

 

[smokey7]

@Ronie what does the unders side of the piston look like? Sure looks hot to me.......

 

[Ronie]

@Ronie what does the unders side of the piston look like? Sure looks hot to me.......

 

[huskyboy]

Very flat.

View attachment 299866

Hmmm. If they were really flat they’d be washing the piston top but I’m not seeing that. Maybe it’s just the oil the previous owner used carbons heavily? Maybe clean off the piston crown, then run it hard for a tank or two of gas after you port it then repost the wash pictures here.

 

[smokey7]

View attachment 299876

Yea looks black and cooked to me.