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Unread 05-21-2002, 12:40 PM   #1
s4b1106
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Join Date: Nov 2001
Location: Idaho
Posts: 13
Its rebuilt, why won't it run?

I need some advice on this one. I just went through the lower end on my 258 because of a severe bearing failure. The thrust bearing went out and took everyone else with it. While in there, I changed the cam and lifters. I didn't re-bore or re-ring as it was building good compression beforehand and not burning oil. The cam is an RV type grind. I don't remember who built it, it came from my local auto parts store. Well, I get her all put together and she won't light. I think my ignition timing is off. BUT I have between 110 to 120 psi in the first 5 cylinders. #6 has 0 psi. I pull the valve cover and manifolds and put the engine at TDC for that cyl, pressure the cyl with an air hose and it is blowing air out of both ports. I loosen up the rocker bolts and it stops. With the bolts out half a turn it builds 120psi. The lifters are hydraulic. I have rebuilt a few engines, so I am not new to turning a wrench, but I didn't think this could happen with hydraulic lifters. Any ideas? And, yes, the parts all went back in the order they came off and no, I didn't forget any shims.

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Unread 05-21-2002, 01:33 PM   #2
OldJeepguy
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</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by s4b1106:
<strong>I need some advice on this one. I just went through the lower end on my 258 because of a severe bearing failure. The thrust bearing went out and took everyone else with it. While in there, I changed the cam and lifters. I didn't re-bore or re-ring as it was building good compression beforehand and not burning oil. The cam is an RV type grind. I don't remember who built it, it came from my local auto parts store. Well, I get her all put together and she won't light. I think my ignition timing is off. BUT I have between 110 to 120 psi in the first 5 cylinders. #6 has 0 psi. I pull the valve cover and manifolds and put the engine at TDC for that cyl, pressure the cyl with an air hose and it is blowing air out of both ports. I loosen up the rocker bolts and it stops. With the bolts out half a turn it builds 120psi. The lifters are hydraulic. I have rebuilt a few engines, so I am not new to turning a wrench, but I didn't think this could happen with hydraulic lifters. Any ideas? And, yes, the parts all went back in the order they came off and no, I didn't forget any shims.</strong></font><hr /></blockquote><font size="2" face="Verdana, Arial">I just finished a total rebuild on my 360 and had a VERY similar thing happen to me. I discovered the problem was that I had installed the new "gee whiz" double roller timing chain wrong. I am not new to the insides of an engine so I discounted the possibility that I could have done thiswrong and spent close to two weeks replacing/adjusting stuff - I even took the timing cover back off and verified the cam/crank timing - and missed it again. The new timing chain has several possible ways to be installed and in fact has two "zeros" on it.
I got the engine running but it developed very little power - after exhausting every possibility I decided to tear the thing down again as I suspected that the cam keyway was indexed wrong from the cam maker. This time I decided to verify the cam/crank relationship to the manual and discovered my problem - the cam was advanced close to 20 degrees - so at TDC on #1 piston I had an intake valve just starting to open.
I corrected the problem and the engine now runs excellent.

I hope you find something simple and can easily correct the problem.
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Unread 05-21-2002, 04:39 PM   #3
s4b1106
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Update: After consulting with several mechanics who told me that the only thing that they could think of was an over sized base diameter on the cam lobes, I spoke with Bill at the place in Phoenix where the crank came from. It is a re-grind (beer budget inevitably means beer parts) and there is no way that the base lobes are oversized. He suggested that there is an air bubble in the lifters, and that they need to be bled down. I never thought of that. Guess I'll find out tonight. Stay tuned! More to follow as it happens!
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Unread 05-22-2002, 12:33 AM   #4
s4b1106
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Update to the update: First, OldJeepGuy, thanks for the info. Problem is different than yours, but almost as simple. After performing, and unsuccessfully at that, the bleed down proceedure as outlined by "Bill", I cried, cursed, and pulled the head. What are the odds??? The intake lifter had the little cap do-dad under the retaining spring jammed skitty-whampus. The exhaust lifter had the little cap do-dad upside down with no spring inside. The intake lifter MAYBE could have happened from a high pressure air bubble pushing it up, but no way on earth that the exhaust lifter could have had that thing turn upside down, and blow the spring out while the retaining spring stayed in place. Sealed Power, bite me!! So, in anticipation of some silly thing like this, I have two new lifters and a head gasket already on order, and with any luck by tomorrow, well, I'll let you know. Lessons learned: ALWAYS check your parts before you install them to make sure they are not only the right one but put together correctly! And, do it on a proper nights sleep! I'm sure that the fact that I was up about 30 hours when I put her together didn't help.
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