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Bad Compression

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Old 10-20-2017, 09:59 AM
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Hey guys.<br />I have a 1999 Dodge Dakota Sport with a 3.9L V6 Magnum, manual transmission.<br />I've replaced the power steering pump (twice) on it, removed the AC Compressor and replaced it with a bypass, until I can afford a new one.<br /><br />Back in June, after I replaced the power steering pump (with a good one, this time), I accidentally lost or broke the little rubber gasket that goes on the heater return tube that comes out of the water pump right behind the power steering pump. I didn't even notice it missing. Anyway, I drove it for a couple of days back and forth to work, 30 miles round trip, so around 60-70 miles. My truck began to overheat and finally the engine shut itself off. When I opened the hood, that's when I noticed the water was spraying out of the heater return of the water pump. I let it cool down and added in more coolant and water in the hopes of getting it home. Afterwards, it wouldn't not crank back up. So, I got it pulled back to my house. I drained out the radiator and replaced it with new 50/50 coolant. I, also, replaced the little rubber gasket that goes onto the heater return tube in the water pump.<br />Well, it still wouldn't crank. I was in the hopes I didn't crack the heads, the block, or head gasket. I drained the oil and found no water in it. I added new oil to it and let it sit for the night. The next day, after letting everything cool down. I tried to crank again, to nothing. Just the whirring of the engine trying to crank. I pulled out the spark plugs. Plugs 2 and 4 had water in them. I drained the oil again and there was water in the oil.<br />After a while of saving up money, I finally ran a compression test on the cylinders. <br />Cylinder 1 - 90<br />Cylinder 3 - 40<br />Cylinder 5 - 40<br />Cylinder 2 - 20<br />Cylinder 4 and 6, I didn't even check because of the low PSi.<br /><br />I have yet to take the head covers off to see if they are cracked or gaskets need replacing.<br />Anyway, my actual question is.... why wouldn't the vehicle crank? I used to own a Firebird that needed the heads rebuilt due to being cracked, but, that car still cranked and could be driven (only drove it to the mechanic shop, though), so, what would be causing my truck to not crank at all?<br /><br />Once I get the head covers removed to check them, I'll give an update. Also, when I get home, I'll get some pictures if that will help.<br />Thanks in advance.
 
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Old 10-20-2017, 12:39 PM
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No Crank: Starter motor does not turn engine.

No start: Engine may or may not crank over, but, if it does crank, won't fire.

With the compression numbers on several cylinders, no, it isn't going to run. Something is powerful screwed up there, and it likely isn't going to be a simple fix. Need to tear it down, and check it out. Likely the heads are trash......
 
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Old 10-20-2017, 01:52 PM
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The truck does try to turn over when I'm cranking it. It just doesn't fire up. There was water in cylinders 2 and 4, but in no others. I've turned the pistons to blow out the water. Tearing down the heads will be done next week to see if anything further is messed up.
 




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