...Or pictures of a bad valve; maybe both.
Never experienced anything quite like this failure before, but in 33 years of
roadster
ownership, it seems there is always something new to keep you interested...
Close examination of the mating face of the head, sure looks like it's
"virgin". No
appearance of having been milled. I think that some of the photos are good
enough to
demonstrate that the combustion chamber looks original.
This was the only occasion out of about a half dozen head gasket replacements
in which I
didn't do it myself--too busy at the time. Cannot understand why Wally's Auto
Repair
used double gaskets in installing the new head.
I had no idea that I have been driving the last 16 years with two head gaskets!
Probably explains why the compression didn't seem quite as high as what I was
used to
with Roadster #1. (Still have its engine with a shaved head).
More valve pictures at:
http://albums.photopoint.com/j/AlbumIndex?u=796901&a=12301734
"David R. Conrad" wrote:
> Tom:
>
> I'm glad you didn't dignify the referenced post with a reply. When I sent
>the msg.,
> I was "flailing around" not knowing what the problem *really* was, (...and I
>didn't
> recall having to remove the water pump for a head removal, but Ross's
>description of
> the "valve regrind kit" containing a water pump gasket, led me astray.
>Thankfully, I
> didn't remove it.)
>
> Anyhow, the head is off. The good news is that my diagnosis was "dead on".
>#1 Cyl.
> exhaust valve has a triangular hole at the edge, about 3/16" on the sides -
>almost
> equilateral. Very strange.
>
> Now, I believe all I need to do, is get a replacement for that valve, and get
>the
> others reground. Then have the seats replaced with stellite vice bronze,
>have the
> stem seals replaced. Then back together.
>
> Now, the strange thing is that there were two head gaskets installed! I had
>brought
> that new head as "carry on" luggage, back from Seattle after purchasing it
>from
> Rallye. It WAS, in fact, new and in the box. Now, why would Wally 's Auto
>Repair,
> Pearl City, have used two head gaskets? Maybe they just had my old head
>shaved and
> kept the new one? Guess I need to have it mic'ed to find out. ...And should
>I use 2
> gaskets?
>
> Curious.
>
> Appreciate any reaction to the foregoing. (Hey, there's no one on this
>island to
> talk Roadsters with :-).
>
> Dave
> '68 1600
> Kailua-Kona
>
> "David R. Conrad" wrote:
>
> > Hi Tom:
> >
> > Your advice to Deena was very timely since I am just now attempting the
> > resurrection of my 1600, down for more than a month. Great to see you back
>on the
> > list, by the way! Your advice has been so valuable in the past.
> >
> > I'm forwarding you several posts to friend, Ross, of Sports Imports of
>whom I've
> > asked some advice about this job I've just embarked upon (started
>yesterday).
> > Finally got that lower, rear nut off the manifolds and starting the removal
>of
> > water pump. Yep, I guess the rather recently installed recored rad. has to
>come
> > off again. (Been quite a while since I've had to pull the head :-).
> >
> > I had reconditioned the head of Roadster #1 in 1978 by a machine shop on the
> > mainland, East Coast, and the current head (new at the time) on Roadster #2
>was
> > installed by a garage on Oahu in 1985, because I was too busy with my job
>to be
> > involved. Other than that, my knowledge of valve job requirements is very
> > limited.
> >
> > Rather than reiterate all the info, I thought I'd just forward what I have
>sent to
> > Ross. I would welcome any thoughts.
> >
> > Thanks
> >
> > Dave
> > '68 1600
> > Kailua-Kona
> >
> > Thomas Walter wrote:
> >
> > > Deena,
> > >
> > > Use the same intake & exhaust valves regardless of unleaded or
> > > leaded fuel.
> > >
> > > Most machinist will know to replace the bronze exhaust valve seats
> > > with a harder material, like Stellite. OEM, bronze, intake valve
> > > seats are fine as they don't have to put up with the heat like
> > > exhaust valve seats do.
> > >
> > > Cheers,
> > >
> > > Tom
> > >
> > > Deena Petrie wrote:
> > >
> > > > Hi list,
> > > >
> > > > Heres another question for you. Remember I'm still learning. Do you
>have to
> > > > replace the valves to be able to run the unleaded fuel? If so what
>type of
> > > > valve should we put in?
> > > >
> > > > Deena Petrie
> > > > 1969 1600
> > > > Westmont, IL
[demime 0.97c removed an attachment of type image/jpeg which had a name of
Datsun Valves]
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