Those pedestals are hardened steel...requires carbide bit to drill into
(yes...we tried a long time ago). The rockers are plain old stamped
steel...hmmmm, hardened steel with stamped steel on top. (You can
figure out the wear on that one.) ;)
Glad to hear it's running strong for ya John. Glad to help ya out
anytime.
- Bernd
-----Original Message-----
From: owner-dakota-truck@bent.twistedbits.net
[mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of John Neff
Sent: Saturday, June 28, 2003 11:12 AM
To: Dakota Mailing List
Subject: DML: Source of iron in oil found and corrected - a little long
The sage, at least to me, is over on where the iron in my engine oil is
coming from. My last oil analysis came back with even higher iron
content than the previous two even though I ran a flush treatment
through the engine on a previous oil change. The analysis is here:
http://jndneff.home.texas.net/dakota/blackstone2/jpg
I decided it was time to find out what was wrong before it stepped and
showed me on it's own the next time I was 500 miles from home and 50
miles away from the nearest garage. I started at the top of the engine
since it was the easiest to get to figuring I'd look at the valve
springs, rockers and pushrods, followed by the cam and lifters and
ending, hopefully, with the oil pump. I pulled the valve covers and
noted that all 16 valve springs looked good. Nothing obviously broken or
out of alignment. Next, I pulled the #2 cylinder rockers. I looked at
the rocker and it's pivot noting that they appeared to be wearing poorly
and felt rough when I moved the rocker against the pivot by hand. I also
noted that the oil groove in both parts was nearly worn away and there
were longitudinal scratches on both parts on their wear surfaces. On the
pivot, there is also a noticeable ledge between the worn surface and the
adjacent surface which does not touch the lifter. The lines which appear
to go directly across the pivot are reflections, but you can see a
diagonal scuff to the left of center just below the oil groove. The
rockers on cylinders 4 and 6 were identical to this one.
http://jndneff.home.texas.net/dakota/rockers/2-intake-p.jpg
http://jndneff.home.texas.net/dakota/rockers/2-intake-r.jpg
I showed this rocker and pivot to Bernd since I trust his opinion and
knows more about these engines than anyone else I know. He agreed that
this was more than likely the source of the iron in my oil. The
dealership he's working at, Allen Samuels Dodge (Used to be Heart of
Texas Dodge) was willing to price match a deal on Mopar 1.7 roller
rockers and valve covers so I ordered the parts from them right then and
there. As I understand it, the price I got on the rockers is actually
below the employee discount so I'll just keep that figure to myself.
While I was waiting for the parts to come in I removed the rest of the
rockers and push rods, but didn't look at them.
When the parts came in three days later we checked them out, found
everything to be present and a pretty shade of blue. They should go
nicely with my truck. :)
http://jndneff.home.texas.net/dakota/rockers/mopar-rockers.jpg
I didn't start the install for a couple of days due to other
commitments. The install went smooth except for two things. First, the
jam nuts provided to install the studs were, I felt, a little thin. By
the time I had finished the last stud on the passenger side, the threads
were buggered up. I replaced these with some thicker nuts from Home
Depot, but they were softer and were trash by the second stud on the
drivers side. I checked out stud installers on Mac Tools web site and
found they look just like the adjustor nuts for the roller rockers. So,
I used one of them to install the remaining studs. This was by far
easier than using jam nuts. Next I wiped the gelled oil of the new
pushrods, dipped them in Mobil 1 and slid them into the engine followed
by loosely installing the rockers and adjustment nuts. Here's where I
ran into a problem. Some of the lifters had bleed down and others had
not. Should I install them to 1/2 turn past zero lash and run it?
Wouldn't that leave me with some being too tight or others too loose? A
desperate email to Bernd told me to get the lifters pumped up and reset
the rockers. So I set the rockers a little loose, dropped the new MP
valve covers in place and fired up the engine. It ran, but sounded like
crap. After about 30 seconds I shut it down, pulled the covers and rest
the rockers to 1/2 turn past zero lash. This time I buttoned everything
down for good and fired her up. Everything sounded smooth and even the
slight ticking I expected from the rockers was not present. The next day
I took the truck down to see Bernd again for his once over check and
listen. He gave it his seal of approval and sent me on my way.
I have about 300 miles on the rockers now and everything is running
great. I'll do another oil analysis on the change after the oil I'm
running now and make sure everything is happy, but I'm confident it will
be. Remember I said I didn't look at the rest of the rockers when I
removed them? Well, today I did and I was a little shocked by what I
found. The rocker over cylinder #8 on the exhaust has a curious problem.
I'm not sure if this was a factory defect, or if a chunk came out of the
pivot sometime in the past 117K miles. In either case, it's not good. If
I buy, or build, another Mopar 3.9, 5.2 or 5.9, I'm going to swap out
the factory rockers before I ever run it. I know 117K miles is
considered high mileage, but this kind of wear scares me. Maybe the
rocker design has worked for Dodge for a long time, but I personally
think it's a poor design.
http://jndneff.home.texas.net/dakota/rockers/8-exhaust-p1.jpg
http://jndneff.home.texas.net/dakota/rockers/8-exhaust-p2.jpg
http://jndneff.home.texas.net/dakota/rockers/8-exhaust-r.jpg
John
http:/jndneff.home.texas.net/dakota/dakota.html
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