another way to hold the valve up is to fill the cylinder with a rope (at
BDC) and then then give the crank a little bump to compress it a little.
Personally.. I would just replace the one bad spring.. then do another
compression test. If all is well. Drive it another 50K miles or so before
I worry about anything else. Since a valve spring should not have broken in
the first place, assume it as more of a fluke break than an actual high
mileage problem. Make sure you do a couple of oil change fairlu close
together.. just in case any particles of spring are circulating around in
there.
Otherwise.. The valve may have actually damaged something that will require
more work. And you'll need to go in deeper.
Also.. glad you found the problem
Just my opinions.
Aaron Wyse
----- Original Message -----
From: "Wilbur" <bwgreen@ocean.otr.usm.edu>
To: <dakota-truck-moderator@bent.twistedbits.net>
Sent: Thursday, January 15, 2004 4:00 PM
Subject: Re: DML: replacing timing chain on 1998 dakota 2.5 liter
>
> You bet I will. :) Ok currently....I put cyl #1 to TDC and injected
> air into sparkplug opening....heard air hissing in valve cover...So
> removed valve cover, and wahlah, i see the first valve at the front of
> the engine (facing the fan and radiator) has a busted spring. I am not
> sure if that one is the intake or exhaust valve spring, just that it is
> the first one in line. The valve has not dropped...it is still
> attached. The valve still could have "kissed" the piston, so to speak.
> So sounds like i need to replace that spring at the very least...and I
> suppose I should replace the other one of the pair too? Should I
> replace all the valve springs and and locks and retainers and valve stem
> oil seals for all 4 cylinders or just for cyl #1?
>
> The push rods looked okay from cyl #1, not bent or anything and I have
> the rockers, bridge and pivot assembly and bolts (also looked fine)
> sitting in a box in the correct order to put back on.
>
> As for replacing the valve springs...from what i can see online, some
> peeps recommend using air pressure via the spark plug hole to keep the
> valve seated while taking off the spring....I don't have an air
> compressor at all to maintain the recommended pressure (90psi) to keep
> the valve seated. Any other recommendations to keep the valve seated
> while I remove the spring? Could I tie some string to the valve stem
> after I have it compressed to keep it from falling into the cylinder?
> Oh and do the valve compressors you can get at autozone and O'reillys
> work for this kind of job? Thanks.
>
> Wilbur
>
>
>
>
> Josh Battles wrote:
> > ""Rick Barnes"" <barnesrv@comcast.net> wrote in message
> >
> >>Josh,
> >>
> >>You blew a ring for that very reason..once you did the great valve job,
> >
> > you
> >
> >>increased the compression in the cylinder and the weakened rings could
not
> >>hold the increased compression..viola, broken rings...common, and your
> >>advice is right on, (in my humble opinion). If you do a valve job, at
> >
> > least
> >
> >>replace the rings too.
> >>
> >>Rascal
> >
> >
> > that's what my uncle told me... (ase master certified mechanic) after
the
> > fact, and while he was helping me replace the rings and smooth out the
> > slight cylinder wall scoring. If I was gonna do it now, I'd do it all
at
> > once and save myself the extra headache later on.
> >
> > learn from our mistakes Wilbur! If you end up having to have valves
done,
> > do the rings now too so you don't have to do them later.
> >
>
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