[DML] Rebuilding a blow motor, continued.

["therealdmcvegas" <dmcvegas@xxxxxxx>]

>From when I last posted, I have since removed the intake manifold, and
have been shocked at what I found. The manifold rings had shrunk into
the heads, and the rings on W pipe were torn. And to fix the vacuum
leaks, some idiot mechanic slathered them with some kind of red
colored, instant gasket material. I suddenly foresee a CO addjustment
in my future... Aside from this, it looks like I've got some serious
buildup. From the air mixture unit, thru the manifold, and all the way
to the intake valves, I have this gold, and black colored crap that's
caked on everywhere. Don't know if it's carbon, or what. But it
scrapes off with a screwdriver, and is everywhere.

After performing a compression test, here are the results for each
cylinder. #1: 160psi, #2: 150psi, #3: 158psi, #4: 168psi, #5: 161psi,
& #6: 160psi.

Now cylinders 2 & 5 are both cross threaded. #5 took allot more
rotations to snuggly hand tighten the adaptor. #2 on the other hand,
took allot less. So I don't know nessisarily that I may have had lower
pressure than on this cylinder was because I wasn't sealing it
properly. BUT, what I did observe was that while every other cylinder
took only 2-3 compression strokes to attain thier recorded pressure,
it took about 5-6 strokes for #2 to hit 150 psi. I go ahead tomorrow,
and (per the test kit's instructions) pout a tablespoon of oil into
the cylinder, and see if I can get a higher reading, to test the
piston rings.

I don't know what the tolerances are for cylinder compression (I
lightly combed thru the workshop manual to try and find them), but I
am a bit concerned about that 18psi difference between my highest, and
lowest pressure cylinders. I have discovered a couple of tiny leaks
from some hose connections under the manifold, and one BIG one on the
left bank of the Y pipe, where it bolts to the block. So a coolant
pressure test isn't really going to tell me a whole lot at this point.
HOWEVER, after my car cooled, I poped the radiator cap. The coolant
bubbled a whole lot, and smelled like gasoline.

Also, while picking up a compression tester, I stubled across a
crossthread repair kit. It was $14, and contained a 14mm tap, and 4
sleeve inserts for repairing aluminum heads. Anyone have any
experience with these?

-Robert
vin 6585 "X"




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