1988 Crew Cab 454 TBI Knock

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Ricko1966

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I pulled the valve cover and everything under there was fine. I then drained the oil and as i was dumping it into the used oil tote I saw some glitter. So I shined a flashlight at it and saw a reasonable amount of metal. I finished changing the oil and started it and it seemed a bit quieter. But before I go jumping to conclusions could it possibly be the air injection system because it seems to run fine besides the knock or is my engine shot?
It's internal engine. Right now you have a pretty good chance of doing a reasonably priced rebuild. Keep driving it and it may not be rebuildsble at all.
 

1975 K20

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What would you suggest replacing if I rebuild it? Do you have an estimate of what it will cost? Would I be better off just swapping in an ls or a diesel?
 

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It's internal engine. Right now you have a pretty good chance of doing a reasonably priced rebuild. Keep driving it and it may not be rebuildsble at all.
Mighty good advice in my opinion. You will have to determine where your budget and talent limits are and go from there.
 

Ricko1966

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Mighty good advice in my opinion. You will have to determine where your budget and talent limits are and go from there.
We used to have a set price to disassemble and reassemble a long block 4,6,8s different prices. If you disassembled it it was more. So people would ask how much to rebuild an xyz. $250.00 to take it apart and put it back together,plus whatever parts and machine work it needs." Oh it won't need very much it was running great before it blew up" Dennis would always tell them,"you probably should have brought it in before it blew up". I have no idea how many times I heard both those quotes.
 
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Knuck55

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Pull the converter cover and make sure all the converter bolts are tight. Seen it before..
 

1975 K20

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Thanks! It has a manual transmission though.
 

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If you wanted to completely rule out top end first, you can pull the intake & check the lifters & cam easy enough with the motor still in the truck. I've also pulled & replaced heads with the engine in the truck(on a 6.2 diesel, no less). All done outside in my driveway. If it's a 4x4(don't think that was specified), you should also be able to drop the oil pan to inspect the bottom end.
 
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1975 K20

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Thanks! I’ll check that when I get a chance.
 

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If you didn't know this already, make sure the lifters & pushrods all go back in the same holes they came out of. Being a TBI, would it have a roller cam?
 

Ricko1966

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If you didn't know this already, make sure the lifters & pushrods all go back in the same holes they came out of. Being a TBI, would it have a roller cam?
Nope TBI is no indicator for roller cam.
 

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Roller cams didn't come until the gen6 454 in '96.
 

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Damn! Just picked up a 95 K2500 & was hoping it had a roller cam.
 
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