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Can i replace post-96 aluminum pistons with pre-96 steel?

darjevon

NAXJA Forum User
Location
MemphisTN
Hi,

I'm rebuilding a 96 4.0 with a cracked head and a blown piston. I recently picked up a set of pistons and a 7210 casting head from a parts yard, in good shape from a low mile rolled 92. I did not realize at the time that the pistons I need to replace in the 96 are aluminum. Is there any reason why this cannot be done? The bore size matches, however the rings are different (e234k, sae height) to the ones in the aluminum pistons (e925x, metric height). I do have the correct rings.

Interesting yet irrelevant: the head on the 96 and the 92 is near identical with only 2 differences. On the 92 head, the coolant temperature sensor sticks out of a threaded bung on the right rear of the head. On the 96, the coolant temperature sensor is in the thermostat housing, however the old style bung still exists and a bolt takes the place of the sensor. Also, there are 3 studs on the 96, 2 of which hold the combination manifold, and one 1 of which holds the AC compressor bracket. The 92 has no studs - instead, it has bolt holes.
 
Should be no trouble - the bore didn't change over time, and the only difference I can recall between the "early" and "late" pistons is that the later pistons have graphite-coated skirts (reduce friction, supposedly.)

Apart from that, no issues I can think of - compression height is the same, and I think the ring grooves are also the same.

If you're going to get rid of the 0630 head, could I get you to check into LTL freight through Greyhound or Amtrak to SJC? I'm trying to collect all the heads so I can section and compare them, and all I've managed to round up so far are a #2585 and a pair of #2586. I'd pay you back for shipping (natch - it's deductible for me anyhow as a "research expense") and I don't care what shape it's in, since it would go through a bandsaw anyhow.

Reminds me - I need to carve out 20 minutes or so to write that "parts I'm looking for" page for WiP...
 
Matthew Currie said:
Just curious, but I am unaware of any pistons made in many a year that are not aluminum. The pistons I took out of my dead 89 were aluminum.

Yea, I highly doubt that any modern (past 40-50yrs) automotive piston is made of steel.

In my 87 they are aluminum, in my 69' and 77' they are too.
 
5-90 said:
Should be no trouble - the bore didn't change over time, and the only difference I can recall between the "early" and "late" pistons is that the later pistons have graphite-coated skirts (reduce friction, supposedly.)

Apart from that, no issues I can think of - compression height is the same, and I think the ring grooves are also the same.

If you're going to get rid of the 0630 head, could I get you to check into LTL freight through Greyhound or Amtrak to SJC? I'm trying to collect all the heads so I can section and compare them, and all I've managed to round up so far are a #2585 and a pair of #2586. I'd pay you back for shipping (natch - it's deductible for me anyhow as a "research expense") and I don't care what shape it's in, since it would go through a bandsaw anyhow.

Reminds me - I need to carve out 20 minutes or so to write that "parts I'm looking for" page for WiP...

Hi, sorry, wish id seen this earlier, I returned it for a core charge of a measly 20. I would have been able to deliver it, as the parts yard was in hayward, not too far from you...
 
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