1993 1hd-t piston selection (1 Viewer)

[asutherland]

Hey all

1993 hdj81... anyone know which "Mark" part number I need? Oh, and anyone know the ring kit part number? (For all 6)

Shows 3 potentials.
131011704001 1HDT..HDJ81 ＳＴＤ,MARK 1
131011704002 1HDT..HDJ81 ＳＴＤ,MARK 2
131011704003 1HDT..HDJ81 ＳＴＤ,MARK 3

 

[roscoFJ73]

13011 RING SET, PISTON
13011-17010 ＳＴＤ (01/1990 - 07/1992) 1 $509.85
13011-17011 ＳＴＤ (08/1992 - 12/1993) 1 $509.85
13013-17010 O/S 0.50 (01/1990 - 07/1992) 1 $614.59
13013-17011 O/S 0.50 (08/1992 - 12/1993) 1 $610.04

Why are the rings dearer than the pistons which are $200-$270?
You might have to put your VIN into an elect parts catalog to get the precise piston part #
I can try it if you PM your VIN

 

[macca1590]

The "marks" are the 3 slightly different size of pistons for the standard bore, hopefully a photo explains it better from a pre 8/92 manual, this is the bore size, there is more pages with piston measurements, rings bearings you name it as well, hopefully someone will pipe up with a link to the workshop manual if not shoot us a pm i think i have it saved somewhere but its for the early 1hdts, not sure if its the same as the 8/92+ 1hdts but i cant imagine stuff like this being much different

 

[IanB]

Ahhhh, that makes sense. So if he punched in his VIN and got these 3 options, they are all the right piston for his application with the only difference being bore diameter, and you'd need to measure the block bore to know which is the one you need.

 

[asutherland]

The illustration above came from searching with my VIN. (3 options)

Jason found a "2" stamped on the top of my pistons. Thanks for the info guys.

Also fwiw, the pistons are different in the 93+ 1hdt.

 

[IanB]

The illustration above came from searching with my VIN. (3 options)

Jason found a "2" stamped on the top of my pistons. Thanks for the info guys.

Also fwiw, the pistons are different in the 93+ 1hdt.

Assuming the "2" marked on top of the piston references the Mark spec, the bore may have worn over the years and could be a different size now than when it was originally assembled...do you replace the one bad piston with the same as it had, or spec it out properly even though you're leaving the rest of the pistons as is?

 

[OGBeno]

Assuming the "2" marked on top of the piston references the Mark spec, the bore may have worn over the years and could be a different size now than when it was originally assembled...do you replace the one bad piston with the same as it had, or spec it out properly even though you're leaving the rest of the pistons as is?

Depends on the rest of the pistons. Each will have their own Mark (1, 2, 3). Each will need to be measure per the specifications and then either bored out (oversize .50mm) if they are not within spec (meaning a new oversized piston) or they can be reused if in specification.

And all 6 cylinders could be Mark 2 or a combination thereof (though I have not seen that much deviation in these "blue print" engines).

 

[asutherland]

Hey beno, apparently all 6 have the "2" mark.

 

[OGBeno]

Then that’s simple. They are all 2.

 

[roscoFJ73]

If an engine is being rebuilt , the machinist usually chooses a piston for each bore. If the bores were being honed I would go to the next biggest size.

 

[Smoke81]

Resurrecting this thread. I tried following along to this but struggling. i am also trying to order 93+ pistons for my early model 1HDT and all my pistons have a #2 stamped on the top. I am trying to order a set through Engine Australia but dont know if they are standard size or not. They are definitely the original pistons, so i guess why would they be anything other than STD? I also know i need to run the 1mm oversized injector washers which is on my running invoice with them. I dont want to order the wrong size as this would be a huge pain going from AUS to the U.S. Any help would be great.

 

[Eurasiaoverland]

If you buy aftermarket pistons (I would only do this if they are branded Japanese, e.g. ART pistons) there will probably only be 1 'standard size' and then one or more oversize (typically 0.50, 0.75 and 1.0 mm on Toyotas). The tiny differences in bore diameter at the factory (linked to the 'MARK' 1,23 etc) will no longer be relevant IMO unless the engine is very low mileage.

As mentioned above, it is your machine shop that should be telling you which size pistons to go for. Why is the engine being rebuilt? Why are you replacing the pistons?

 

[Smoke81]

If you buy aftermarket pistons (I would only do this if they are branded Japanese, e.g. ART pistons) there will probably only be 1 'standard size' and then one or more oversize (typically 0.50, 0.75 and 1.0 mm on Toyotas). The tiny differences in bore diameter at the factory (linked to the 'MARK' 1,23 etc) will no longer be relevant IMO unless the engine is very low mileage.

As mentioned above, it is your machine shop that should be telling you which size pistons to go for. Why is the engine being rebuilt? Why are you replacing the pistons?

I am replacing pistons/rings only due to a cracked piston in cylinder #4, no bore damage. i just figured i should run the later pistons with the larger bowls.

 

[TheBussman]

Resurrecting this thread. I tried following along to this but struggling. i am also trying to order 93+ pistons for my early model 1HDT and all my pistons have a #2 stamped on the top. I am trying to order a set through Engine Australia but dont know if they are standard size or not. They are definitely the original pistons, so i guess why would they be anything other than STD? I also know i need to run the 1mm oversized injector washers which is on my running invoice with them. I dont want to order the wrong size as this would be a huge pain going from AUS to the U.S. Any help would be great.

If your sure it's original and your not boring the block to the next size it's for sure standard. All the numbered pistons 1 2 and 3 are always standard. Best to measure with a borscope though to make sure that's the way to go if you have oval or taper best to bore out.