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Old 06-25-2012, 11:28 AM
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Hey All,


Doing a follow up to the truck's driving issues. The truck has been running fine after being timed by ear last time. I was supposed to have base-timed it and report back three months ago, but a few things came up that kept me from working on it. Right now, its parked and being readied for a smog check.




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The truck still seems to be leaking and/or consuming large amounts of oil. I thought it was the valve cover gaskets again, but they seem to be ok. While I have not verified it, I believe the rear main seal is to blame.




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Two weekends ago, I did a base timing on the truck by disconnecting the vacuum advance, plugging all ports and using a timing light. The reason why the timing mark was never falling onto the marker tab was because the the distributor was turned too far advanced. I brought it down to 9*, took it for a very quick spin, and it drove just fine. That's not where I am going to leave it, but it is in a very good spot. Wasn't able to figure out how to do total timing on the timing light itself (Pugsy, if you're reading this, I can use some help since you said you have the same light as mine)




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I also went and head and addressed all the issues that were brought up regarding the carburetor. All results have been posted here: Post #145



Quote:
Originally Posted by cobalt327
The red cam-shaped plastic piece is the eccentric that lifts the secondary hangar/secondary metering rods in relation to the air valve opening. It has to be replaced, Ruggles has the kit, $12 to your door.
I ordered the kit from Ruggles and replaced the cam, the "tension spring" for the shaft, as well as the screws for the air flaps.




Quote:
Originally Posted by cobalt327
On thing that you have got to fix is the small hook that clips to the needle part of the needle and seat assembly. The hook does not go through the hole in the float arm. This is a common mistake, but it can cause the needle to hang up and the float level can be all over the map. So, hook it over the cross piece closest to the power piston.
Got that fixed.




Quote:
Originally Posted by cobalt327
I'd remove the epoxy. It's not doing any good and even though it can't fall into the float bowl, no reason to have it going through the engine. I'm guessing it was there for prevention's sake. If the well plugs ARE leaking get back to the forum and we can get into it further.
I completely removed it all.





Quote:
Originally Posted by cobalt327
EDIT- The air bleed that's damaged needs to be opened back up to the same diameter as the undamaged one. You can use a small pick or smooth nail if small enough to resize the opening to match the other one. Dress the air bleed tip so there's no ragged edges, just don't shorten it excessively (excessive would be more than say 0.015").
Quote:
Originally Posted by barry425
You can use an oxy-acetylene welding tip cleaner to clean up the air bleeds. Just don't get too vigorous with it, since the tip cleaners are actually little round files and will take off metal.
I used the oxy-acetylene cleaner and filed 'em clean by starting with a small size and kept increasing until I maxed out without removing any material from the tubes themselves.




Quote:
Originally Posted by barry425
I hope you sprayed the venturies to get them clean. they looked pretty nasty.
I sprayed them with carb cleaner and wiped them down with the shop towel. They seem a little better now..




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Quote:
Originally Posted by sbchevfreak
Is it just me, or do the "even" plugs look to be badly oil fouled? If so, I would be looking at intake gasket sealing on that side....
Quote:
Originally Posted by SSedan64
They do look oil fouled and the Spark Gap looks "HUGE" What are you gapping your Plugs at?
I removed the plugs again yesterday to see how fouled they are now and to determine if the intake manifolds need to be replaced. The truck has been driven less than 100 miles since the last time the plugs were checked (see image in post #9 here for comparison). Upon removal, the spark plugs appeared to be covered in even more oil than last time. Cylinder #1 was thickly caked in oil. But oil spots on the shop towel from the wipe down don't seem to be any worse. Any ideas? Does intake manifold gasket still seem like a concern?







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Quote:
Originally Posted by cobalt327
Was a compression test done on this beast? Results?
While I had the plugs out, I went ahead and did a compression test yesterday. I was doing it by myself so my procedure was to let it crank for five seconds, and record the result. I did each cylinder three times. Below are the results.

Cylinder . . . . . Test #1 . . . . . Test #2 . . . . . Test #3 . . . . . Average

1 . . . . . . . . . . . . . 165 . . . . . . . 165 . . . . . . . 165 . . . . . . . . . 165


3 . . . . . . . . . . . . . 170 . . . . . . . 170 . . . . . . . 170 . . . . . . . . . 170


5 . . . . . . . . . . . . . 165 . . . . . . . 165 . . . . . . . 165 . . . . . . . . . 165


7 . . . . . . . . . . . . . 160 . . . . . . . 160 . . . . . . . 160 . . . . . . . . . 160


2 . . . . . . . . . . . . . 160 . . . . . . . 160 . . . . . . . 160 . . . . . . . . . 160


4 . . . . . . . . . . . . . 160 . . . . . . . 160 . . . . . . . 160 . . . . . . . . . 160


6 . . . . . . . . . . . . . 160 . . . . . . . 165 . . . . . . . 162 . . . . . . . . . 162.33


1 . . . . . . . . . . . . . 165 . . . . . . . 165 . . . . . . . 165 . . . . . . . . . 165


Percent difference between highest average (170) and lowest average (160): 6.25%
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