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  #31 (permalink)  
Old 03-02-2013, 08:06 PM
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Heads are back from the machine shop. The owner cleaned all the oil and crud off them and checked them out. He stated they did not need a full valve job and were just fine. There was a fair amount of oil burnt on to combustion chambers, but now their all clean. Got to love dealing with honest people. He could have just did the full work and charged me but instead it only cost me $40.00. I will be installing an oil catch can inline with the pcv valve as I'm suspecting that oil is being sucked in the intake manifold and causing detonation that sounds like the valve chatter. I've also clean off the piston faces so everything should be all set.
I'll be getting an early start tomorrow and should have my motor all back together my noon.

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  #32 (permalink)  
Old 03-02-2013, 11:10 PM
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awesome thats good to know, sometimes its better to spend a couple bucks and know what your working with, you do not need to run a pcv to the carb btw, all the pcv is way for the engine to vent combustable gasses back into the engine for better fuel economy so if this is not a pollution controlled engine then replace the pcv with a valve cover breather, and make sure there is one on each valve cover, i learned this the hard way
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  #33 (permalink)  
Old 03-03-2013, 09:46 PM
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Well it's taking longer than I expected to put my motor back together. Ran into some delays cleaning off the burnt oil/carbon off the piston faces. The good news is I was able to really take a good look at every piston wall, all the lifters, and the cam lobes all check out fine.
The heads are installed, base valve adjustment complete.
Still need to install the intake manifold, carburetor, exhaust manifold, distributor, oil catch can set the timing, and do the final valve adustment.
Looks like I'm taking a day of tomorrow to finish.
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  #34 (permalink)  
Old 03-03-2013, 11:44 PM
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Before you continue the assembly it probably wouldn't hurt to redo a pressure test on cylinders 4 and 6 to make sure they are holding and something wasn't over looked
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  #35 (permalink)  
Old 03-04-2013, 08:48 AM
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All I can hear is a bunch of rearend noise and occasionally a faint ticking noise. Is there headers or manifolds on this vehicle?

peace
Hog
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  #36 (permalink)  
Old 03-04-2013, 11:11 AM
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Quote:
Originally Posted by Hogg View Post
All I can hear is a bunch of rearend noise and occasionally a faint ticking noise. Is there headers or manifolds on this vehicle?

peace
Hog
Sanderson QP1000 cast iron headers
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  #37 (permalink)  
Old 03-04-2013, 11:11 AM
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Quote:
Originally Posted by Northern Chevy View Post
Before you continue the assembly it probably wouldn't hurt to redo a pressure test on cylinders 4 and 6 to make sure they are holding and something wasn't over looked
Good idea, I'll do that first thing this morning.
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Old 03-04-2013, 02:16 PM
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Quick update whitle I wait for the RTV to setup. I hooked up my airline adapter to the 4 and 6 cylinders and the air leak is gone. So it looks like it was either the built up crud in the head or the old head gasket that was the air leak issue.
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  #39 (permalink)  
Old 03-04-2013, 10:46 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
Too bad you did not take advantage of the situation and degree and advance the .450"in.460" ex camshaft in this motor.
( If you were to degree it you would find it is retarded (115in/113ex C/L's) 114LSA (retarded by 1deg)
Moving the cam to a new 107in/121ex C/L position (7degree advanced) will wake it up and make more torque in this low cr engine. as the intake valve will close sooner.
This cam was GM's origional 1969 11:1 ccompression 350-350HP L-46 cam.
As installed it is a mis match @8.5:1cr. It need to be advanced.

If the new head gasket is thicker than the old stock head gasket the compression ratio wil now be even lower.
Should have wacked some off the heads (.050") and used a felpro shim head gasket.
I would have home ported the heads too.
When I had the heads off I put it to TDC and it was already set to 6 degrees advance.
Unfortunately I ran into more delays today. Got everything put together, but when I fired her up she ran for about 20 second then died. Need to trouble shoot tomorrow and do the final dial in on the timing and valves.
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  #40 (permalink)  
Old 03-04-2013, 11:17 PM
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I think the cam can be advanced 6 by using the dot to A on the timing chain gear set. He could have checked that visually at tdc.
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  #41 (permalink)  
Old 03-04-2013, 11:38 PM
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Yes , degree and measure.

Okay , no multi key. I was trying to mind read.
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Old 03-05-2013, 09:09 PM
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Quick update, finally got the FJ40 running and idling smooth. Timing is all set and I finished half of the final running valve adjustment. All I have left to do is finish the the passenger side valves.
So far all of the previous issues are gone. No detonation/valve chatter, no single tick when I turn off the motor, all the pistons are firing perfectly. Can't wait to test drive it tomorrow night.

On another note....I really like the MSD Digital E-Curve distributor. After I learned how to set it up it's so easy to deal with. Nothing like being able to change the curve in just a few seconds.
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Old 03-06-2013, 09:05 PM
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Finaished up the valve adjustment and took it for a test drive.....So that's how it's supposed to run.....What a difference. I want to thank everyone for all their advice. You were all a great help.
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  #44 (permalink)  
Old 03-06-2013, 09:38 PM
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So throughout the repairs or tear down of the top end, did you ever really nail down what was causing this "rattling" ... was it valves floating with really weak springs or perhaps preignition due to an extreme amount of carbon build up and was that from too rich a fuel mixture or was it using excessive amounts of oil ? . Then the matter of the mystery air loss in two cylinders as you pressured them up. Just curious to find out what was really going on inside that engine.
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Old 03-06-2013, 11:10 PM
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Quote:
Originally Posted by Northern Chevy View Post
So throughout the repairs or tear down of the top end, did you ever really nail down what was causing this "rattling" ... was it valves floating with really weak springs or perhaps preignition due to an extreme amount of carbon build up and was that from too rich a fuel mixture or was it using excessive amounts of oil ? . Then the matter of the mystery air loss in two cylinders as you pressured them up. Just curious to find out what was really going on inside that engine.
I'm going with the extreme amount of carbon. It was really caked on the piston faces and the heads were covered in sludge. This was most likely caused by oil getting sucked up through the PCV valve since my valve covers had no baffles. It also looked like there was an issue on the old head gasket between those 2 cylinders. The gasket came of clean and you could actually see an issue.
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