2F Pistons???

[andrew7elk]

I am rebuilding my 2F, After removing the head i have noticed that the pistons have "30" Stamped on the top of the piston. Does this mean that these pistons are .30 over or is that a normal marking. Do stock pistons have anything stamped on the top of them. (They are flat top pistons if that helps)

Also what size are stock pistons?

Any information will help


Thanks in advance!!

 

[tonkota]

My over sized pistons had a metric designation. 3.70" bore for a stock 2F or 3F.

 

[D'Animal]

Mine had a 46 and a 33 stamped on them.

 

[andrew7elk]

Mine had a 46 and a 33 stamped on them.

Are they oversized pistons??

 

[D'Animal]

Nope. Not that I could measure with a dial caliper.

Are they oversized pistons??

 

[andrew7elk]

Thanks for you help, i have found out what the markings mean.

If your pistons are over 30 sized it will be stamped ".030"

Having a single number (like 3 or 30) stamped on each cylider indicates that it is a original set of pistons. If you have a piston with a different number than the rest it means it has been replaced.

Hope this makes sense.

 

[tonkota]

Thanks for you help, i have found out what the markings mean.

If your pistons are over 30 sized it will be stamped ".030"

Having a single number (like 3 or 30) stamped on each cylider indicates that it is a original set of pistons. If you have a piston with a different number than the rest it means it has been replaced.

Hope this makes sense.

Where did you find this information? I'm curious. IIRC, my 3F-E pistons I took out had 30 or 50 on them. I'll have to check (I kept them).

The replacement pistons had a 5 on them for 5mm over (about 0.20").

 

[60wag]

Mine had a 0.5 for 0.5mm or 0.020" over stock.

 

[lehiguy]

Where did you find this information? I'm curious. IIRC, my 3F-E pistons I took out had 30 or 50 on them. I'll have to check (I kept them).

The replacement pistons had a 5 on them for 5mm over (about 0.20").

That's not what that means. 5mm is TONS more that .020"

 

[tonkota]

Mine had a 0.5 for 0.5mm or 0.020" over stock.

That is what I meant

 

[lehiguy]

That is what I meant

That makes sense.

 

[Louis Ciccoli]

Hoping to get some more info, as I too have pistons that are marked "050". They're could be a decimal before them, but the carbon build up makes it pretty tough to read. All of them, from what I can tell have it. I know there's been work done, as several of the bolts getting into the head removal area aren't as they should be. Slightly rounded, different looking head, etc.
Also, since I hopefully have someone's attention, are there supposed to be water jacket passages blocked off between the head and block with the head gasket? I'm wondering if whoever did the work before me didn't use an OEM gasket? I have a new one on the way, so I'll see for sure when it gets here.

 

[Spike Strip]

Your engine has been rebuilt. Aftermarket pistons. Not a Toyota HG. Lack of Coolant/Antifreeze maintenance.

 

[Louis Ciccoli]

Your engine has been rebuilt. Aftermarket pistons. Not a Toyota HG. Lack of Coolant/Antifreeze maintenance.

Thanks, when you say "lack of", you mean flow, or quantity? I've done some other repairs to it, including a new aluminium radiator and fan clutch, as the prior ones didn't work anymore. I've had no over heat issues, however I'm still getting contaminants in my coolant. I'm guessing due to lack of proper flow through out the coolant system?

 

[Spike Strip]

You could have blockages but the rust-water shows it needs to be flushed. If you're running an Aluminum rad, I would super flush the system and run Toyota red pre-mix.

I don't know anything about those Fel-Pro gaskets since I've never used one.

When I say 'lack of' I mean the anti-corrosion inhibitors were all used up because Coolant was not changed often enough or garden-hose water was used to dilute anti-freeze. Coolant may still be green, but Alum rad will deplete inhibitors faster in a system that was designed for brass/copper radiator. Toyota Red has much higher levels of inhibitors but you have to get all the old green stuff and crud out.

 

[Louis Ciccoli]

You could have blockages but the rust-water shows it needs to be flushed. If you're running an Aluminum rad, I would super flush the system and run Toyota red pre-mix.

I don't know anything about those Fel-Pro gaskets since I've never used one.

When I say 'lack of' I mean the anti-corrosion inhibitors were all used up because Coolant was not changed often enough or garden-hose water was used to dilute anti-freeze. Coolant may still be green, but Alum rad will deplete inhibitors faster in a system that was designed for brass/copper radiator. Toyota Red has much higher levels of inhibitors but you have to get all the old green stuff and crud out.

Gotcha, and thanks. Once I get it all buttoned back up, I'll make sure to do a good flush on it.