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88 4.0 rebuilt won't crank


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So I have this 88 jeep put together this morn. Prime oil pump. Made sure timing was right. Has a new reman 2868 head on it. won't start- just yun yun… a friend of mine suggested to back of the rockers. I had em at 19ft lbs but he said to back em off til you can just turn the rod. Right now there is no compression. New rings, pistons, wrist pins, rockers, rods, lifters….i mean rebuilt. Any suggestions

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Try a leak down test. Basically you use an adapter that threads into the spark plug hole that allows you to hook up an air hose to pressurize the cylinders. Then you find where the air is escaping. One of 4 places; intake (bad valve), exhaust (bad valve), crankcase (piston problems), or radiator (bad head gasket).

 

If you buy a leak down tester some have gauges where you can check the pressure and watch what is is doing. Some are just the air hose to spark plug adapters.

 

Edit: both valves need to be closed to get good results

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So. I got it cranked….. had to back the rockers wayyyy off. Its shooting oil 8ft like into air (what a mess). Anyway, i put Vc iver it and cranked, tighten rockers a bit more, cranked, tighten rockers a bit more, cranked, til it wouldnt again then backed off. 🤦🏻‍♀️😑. The reman head a problem?

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Then…. I left it running trying to get the antifreeze back in it, drove it forward backward, and putting it back in shop amd it died and wouldnt crank again… which could be me trying to get water burped back in it. 

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There are a few stock length push rods. Then there's 4.0L vs the 258 push rods(longer). I am running up to this, with my mini-stroker.  I am using 9.623 right now. I might go down to 9.594s. I am using HS roller rockers. I do have a reground cam. Base circle about .080 under stock. Also, there are two different lengths of stock push rods. 9.640 and 9.650. 

      I would say you are correct, that the head deck has some material taken off. Probably part of what I am dealing with. 

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