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Discussion Starter #1
Hey everyone, I'm new here and am looking for some advise. I'm buying a 98 chevy 1500 with a "blown" 4.3 vortec. Guy says the motors not seized but I'm going to check it out tomorrow. Question 1 - any advise on what to look for to see if the motor is salvageable?
Question 2 - I found a 4.3 out of 00 blazer with about 100k miles for $500, is that a fair price and would it work in the 98 truck?

Thanks in advance for the help!
 

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A "blown" engine is not usually salvageable.

To me, the term blown is used incorrectly to mean a rod has gone through the side of the block.
 

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The 2000 engine should work just fine, but you may need to swap some of the parts from the 98. All in all, they are the same engine, block for sure, and heads should be the same too. As for the intake, fuel injectors, ect IDK for sure.
 

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Discussion Starter #4
I agree, I just looked at it today and didn't see any evidence of anything coming thru the motor. The guy tried starting it and to turned over just wouldn't crank. His explanation was the truck ran hot with only water in the radiator (I live in Florida so 100+ degree days are common) and then it quit running.

I'll do some checking into it some more in the next couple of weeks, bought it from him.

Thanks for the input on the blazer 4.3, I'm going to tinker with this one before I go swapping the motor out but I'll definitely keep that donar vehicle in mind
 

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Maybe your working with a dead battery, or a bad starter.
Remove the plugs (no compression is easier to turn) and try turning the crank with a wrench.
 

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Discussion Starter #6
Battery is charged and starter will turn the motor over it just won't fire up. I'm going to have it towed to my house on Tuesday of next week and will start to check it out. Not sure what to check first so I'll start doing some research and make sure I'm getting fuel, spark and good air flow
 

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Ok, terminology problem.
No big deal; but it does lead us down the wrong rabbit hole when trying to solve the problem.
In the old days, before starters, the engines were started by human power.
A tool was used by the driver to spin the engine. This tool was called a crank.
From that tool, the term crank has been used to describe the function of the starter.
The starter "cranks" the engine.

So, in your case, the starter cranks the engine; but the engine won't fire (start).

Now, this tells us a lot.
The engine isn't seized.
There is no broken rod.
It won't start.
It needs fuel, air and spark, you are probably missing one of the three.
 

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Discussion Starter #8
Okay sorry about that, thanks for your patience with me. So I'll check for those things and will give an update. I'm seeing online that I should probably do a compression test as well, is that another good thing to check or should I just worry about fuel air and spark first?
 

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Hey, it's no big thing, just trying to help.
The second tool I bought (not counting wrenches) was a compression gauge (the first was a vacuum gauge). Checking the compression is a very good idea, it's like a doctor checking your blood pressure. Knowing those numbers is the place to start.
Because, along with fuel, air and spark, you need compression.
 

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Discussion Starter #10
Awesome sounds great, I'll have more info in a couple of days and will get you an update!
 

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Discussion Starter #11
So I couldn't wait to start getting this motor problem figured out so had her towed to my house today. Filled the radiator with water and started noticing a leak from around the water pump after a couple of minutes. I'll get a better look tomorrow to see where all its leaking from.
 

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Discussion Starter #12
So did a little with the truck today. Checked compression on 3 of the 6 cylinders 150psi on the center passenger side, 170psi on the front passenger side and 140 on the center drivers side. All held pressure for 10 minutes. Verified that I am getting fuel but hooked up an inline spark tester and am getting some light but not nearly what I thought I would see. Is there a better way to check for spark that can be done single handedly? Also is it worth checking the other 3 cylinders for compression or was my test today good enough?

Thanks in advance!
 

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Don’t guess. Do check them all. It would be like not checking all the blood vessels in your heart and then you die from a clogged artery.
 

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Don’t guess. Do check them all. It would be like not checking all the blood vessels in your heart and then you die from a clogged artery.
I agree. Do both a dry test, then a wet test. It will tell the tale if you have cylinder/ring wear.
 

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Ok, terminology problem.
No big deal; but it does lead us down the wrong rabbit hole when trying to solve the problem.
In the old days, before starters, the engines were started by human power.
A tool was used by the driver to spin the engine. This tool was called a crank.
From that tool, the term crank has been used to describe the function of the starter.
The starter "cranks" the engine.

So, in your case, the starter cranks the engine; but the engine won't fire (start).

Now, this tells us a lot.
The engine isn't seized.
There is no broken rod.
It won't start.
It needs fuel, air and spark, you are probably missing one of the three.
Requires something else - the right order - timing chain could have jumped
 

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Requires something else - the right order - timing chain could have jumped
Well, we could get crazy and also add that we need a clear exhaust to get rid of the gas,
We also need the correct fuel pressure,
We also need the correct octane for the fuel.
Etc, etc, etc
But, your right, all of those thinks are necessary before an engine will fire.
 

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Discussion Starter #17
Well I had some progress last night, all the compression checks were good but found little to no spark coming out of the ignition coil, replaced it and she fired up first try
 
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