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No compression!!
You can see the mods I just finished installing. Well we blew the head gasket. Wrong one. Put the truck all back together with the proper gasket. Now it turns over like no compression or very little. Valves and lifters all all moving like they should. All six cylinders do not have compression.
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I am sure that more experienced folks than me will chime in here but if there is no compression on all 6 cylinders, I would suspect that your head isn't seated properly. I can't imagine a head cracked so badly that you would lose all 6 cylinders and not notice it and there can't be any valve/cam pos'n that would have a valve open in every cylinder at the same time.
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We were thinking cylinder wash down from blowing HG or I seized the rings from it getting hot. Im At a complete loss right now.
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I hate to ask but did you set the valve clearance after new head gastket install? No shop towels or rags in the intake? Camshaft gear indexed correctly? Compression is going somewhere, pull oil cap any compression felt blowing out. Pull intake hose any compression blowing out. You did put the valve bridge back on? 600 psi compression should be easy to find where it is going you would think. If piston seized you would have seen scooring on cylinder walls when head was off. I'm thinking complete blockage at intake somewhere. Pull hose at intake see if you get compression. I've seen emergency shut down device on intake cause same problem when driver hit runaway shutdown switch by mistake. Engine became a big vac pump no air no compression.
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We have the head off the cylinder walls still have the cross hatching from the factory on them. When turning the engine over with one injector out there was a small amount of compression but not nearly what it should have. If it was 50 psi it was alot.
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Before we blew the head gasket the truck was driven close to 200 miles. We had a boost leak and only made about 20 psi so it survived. I would think if the cam was indexed wrong it would have shown up then. Once we fixed the boost leak we blew the HG immediately. Lost six quarts of oil. The truck was still purring like a kitten. We put oil in and started it several times after to determine where it was coming from it still ran fine. Even with compression blowing out the front of the head.
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When doing compression test did you have intake boost hose off? I've seen diesels with holes in the pistons and still run. If it is effecting all the cylinders it has to be intake related. Pull the hose off and rerun compression test. You can try pulling #1 injector getting piston at TDC and see if both valves (rocker arms) are loose and TDC mark on dampener is at the TDC mark. You can also try if you have air compressor running a leak down on cylinders which will tell you if rings and valves are sealing properly. May need to borrow or buy leak down tester.
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We had the entire intake removed with the valve train and injector removed on #1. Correct me if I'm wrong but there should be significant compression being blown through the injector hole. We turned the motor over with a rag on top of the opening and it did not move it.
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Yes it would blow any rag out of the injector hole, You may have to get a leak down tester to find % of leakage past the rings
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I use the leak down tester all the time on gasers. I had one this week overheated badly no compression afterwards never seen it happen to a diesel yet but always a first time. You can use your compression tester with a leak down tester if it is showing 100% leakage pass the rings then they could all be stuck rings in the pistons.
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I'm worried about stuck rings as well but if all six rings are stuck I would think there would be at least some cylinder wall scoring?
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something is wrong if it ran when you took it to the shop, it should run after. you need to re check and make sure the head is on right and the install was done right.
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As mentioned hard to believe all rings could be stuck and no cylinder wall damage. I would double check your valve timing, the marks are 1 to 2 on both not 1 to 1 and 2 to 2. Have you tried squirting some oil into a cylinder to see if the compression comes up this would show if the rings are stuck or the valve timing is out.
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I don't know what you are talking about with valve timing and marks that is determined by the cam?
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So we put the other gasket supplied with the kit on and re adjusted valve clearance. Low and behold upon cranking it sounds like it has compression in all six cylinders. I'm thinking and hoping disaster averted at this point. Won't know for sure until it is all together. We have had the head off five times now hopefully this is the last time. Thanks for the help gentleman. Fingers crossed it runs and the head stays on.
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