Mystery Knock Found!!!
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Mystery Knock Found!!!
Number 8 ain't so happy. I was going to just replace the one slug and rod through the bottom but since I gotta yank the passenger head off anyway, I figured I might as well find a good roller shortblock to stuff my cam and timing set in.
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Yeah, that's what it seems like to me too. I was fully expecting that on number 7 but number 8 suprised me. I had a bad cylinder head that was blowing coolant through the exhaust on number 7. To be fair, this 87 was/is a parts car so I had no idea what was wrong with it. Clearly, I am finding all of the issues. lol But a new short block has been identified so I am not too worried. Hydraulic roller block out of a 91 truck. Pistons look to be the same so I don't think I will take a hit on compression.
Edit: That TBI roller block is not a roller. I lied. But I have eyes on a different one. Might have to drill and tap for the cam retention plate, but that ain't a big deal.
For those interested in the sound of the knock, when I move forward to the front you can hear it pretty well.
Edit: That TBI roller block is not a roller. I lied. But I have eyes on a different one. Might have to drill and tap for the cam retention plate, but that ain't a big deal.
For those interested in the sound of the knock, when I move forward to the front you can hear it pretty well.
Last edited by marshallnoise; May 19, 2025 at 08:27 PM.
Melting Slicks
Joined: Nov 2016
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From: So Cal
2023 C4 of the Year Finalist - Unmodified
I've R&R'd a crankshaft in a 4.3 V6-90 without removing the heads or intake or even the distributor. Engine was out, and on a stand.
I remember the hole in the head on #7. That looked like corrosion damage weakened the casting internally, then a hydro-lock event blew the piece into the water jacket.
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Only one of the eight pistons and rods will come out the bottom. I forget which one does I think it is #2. The others hit their main bearing saddles. The crank shaft must also be removed. R&R out the bottom is not viable. How you going to rig a ring compressor? And the crank shaft has to be removed which might as well remove the engine.
I've R&R'd a crankshaft in a 4.3 V6-90 without removing the heads or intake or even the distributor. Engine was out, and on a stand.
I remember the hole in the head on #7. That looked like corrosion damage weakened the casting internally, then a hydro-lock event blew the piece into the water jacket.
I've R&R'd a crankshaft in a 4.3 V6-90 without removing the heads or intake or even the distributor. Engine was out, and on a stand.
I remember the hole in the head on #7. That looked like corrosion damage weakened the casting internally, then a hydro-lock event blew the piece into the water jacket.
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Joined: Sep 2024
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Completely tore down my old block (well, not the crank) and more damage was discovered. Not only was number 8 bent, so was number 6. And on number 7, where I had a chunk of the cylinder head break off in the chamber, it hit the head on the way up and pinched the ring land on the upper ring so that ring was not moving.
Fortunately, I picked up an 85 block with the factory forged pistons and the eyebrow trough valve relief. The bearings were worse than my regular bearings and so I picked up a set of cheapie Sealed Power standard rod bearings and slapped it all together. Waiting on new head gaskets and intake gaskets to get it all back together.
Fortunately, I picked up an 85 block with the factory forged pistons and the eyebrow trough valve relief. The bearings were worse than my regular bearings and so I picked up a set of cheapie Sealed Power standard rod bearings and slapped it all together. Waiting on new head gaskets and intake gaskets to get it all back together.
