Other than a good replacement head, most of the measures suggested are a patch
in
one form or another. Each has its merits and downsides, but I don't think the
intention
was to rebuild the whole engine or swap in a U20.
A good head is certainly the best option, but that can get pretty pricey too.
A really good
core is worth a bit, then you clean, pressure test, surface, seats?, guides?
fix threads etc.
adds up. Still this may be the best option if you are unsure what is below.
I would only cut the domes if the bottom end is low mileage, forget it on a high
mileage motor. As pointed out, if the crank, pistons, bores aren't in real
good shape
you may as well pull the engine. If the lower end is tired don't open it up
unless you can go
all the way or be prepared to swap it for another.
Jim Tyler
----------
From: PATRICK P. CASTRONOVO[SMTP:slick@mohaveaz.com]
Sent: Saturday, October 02, 1999 12:38 AM
To: Jim Tyler; BERKEN@aol.com; datsun-roadsters@autox.team.net
Subject: Re: R1600 Head Stuff
I was not aware of that. I thought they were basically the same engine
except for the cam, and carbs. You learn something new every day on this
list. So then he still has the problem of his pistons hitting the valves.
If he has to pull the pistons to cut the domes off, then he may as well put
in new pistons. If he pulls the pistons, he may as well put in new rod
bearings. As long as he has the pan off to put in new rod bearings, he may
as well go the distance and put in all the main bearings. OH, Hell! To do
all this you must pull the engine. May as well take the engine to a Machine
shop and let them rebuild the whole kit and kaboodle. Then put it back in,
and just drive.
-----Original Message-----
From: Jim Tyler <jtyler29@idt.net>
To: BERKEN@aol.com <BERKEN@aol.com>; datsun-roadsters@autox.team.net
<datsun-roadsters@autox.team.net>
Date: Friday, October 01, 1999 9:18 PM
Subject: RE: R1600 Head Stuff
>No it is an overhead valve, not overhead cam.
>
>Jim
>
>----------
>From: PATRICK P. CASTRONOVO[SMTP:slick@mohaveaz.com]
>Sent: Friday, October 01, 1999 10:49 PM
>To: BERKEN@aol.com; datsun-roadsters@autox.team.net
>Subject: Re: R1600 Head Stuff
>
>Do you mean to say the 1600 does not have an overhead cam?
>-----Original Message-----
>From: BERKEN@aol.com <BERKEN@aol.com>
>To: slick@mohaveaz.com <slick@mohaveaz.com>;
datsun-roadsters@autox.team.net
><datsun-roadsters@autox.team.net>
>Date: Friday, October 01, 1999 7:38 PM
>Subject: Re: R1600 Head Stuff
>
>
>>In a message dated 10/01/1999 10:05:11 AM Mountain Daylight Time,
>>slick@mohaveaz.com writes:
>>
>><< When I took my 67.5 2000 head in to be worked on, the machinist that
>worked
>> on it was not familiar with overhead cams, or he did'nt care about what
he
>> was doing. He milled the head, almost to a point of eliminating the
>> combustion chamber. I have installed two head gaskets, and the most
>> important thing is you need to have a machine shop make you cam tower
>shims.
>> Otherwise your timing chain will have too much slack in it, and possibly
>> will break, or at the least, jump time. Neither of which would be
>> acceptable. In the long run, it may be cheaper for you to purchase a
new,
>> or used head and start over.
>> -----Original Message-----
>> From: Robert.Long@CSDInc.com <Robert.Long@CSDInc.com>
>> To: datsun-roadsters@autox.team.net <datsun-roadsters@autox.team.net>
>> Date: Friday, October 01, 1999 8:37 AM
>> Subject: R1600 Head Stuff
>>
>>
>> >Hi,
>> >
>> >I just had the head from my 1600 milled. It mic-ed to 3.175. What is
>the
>> >minimum?
>> >
>> >I assume this is below tolerance, because I put it back on, without the
>> >gasket, and finger tightened the
>> >head bolts, and the pistons are making contact, when I manually crank
it.
>> >
>> >Is there anything I can do to save this head? It's in pretty good
shape,
>> >minimal pitting, valves look good.
>> >
>> >What about a shim, or double gasket?
>> >
>> >Thanks for your ideas - Robert Long - 67.5 headless 1600 - Albuquerque,
>NM
>> >
>> >
>> >
>> >>
>>
>>Robert,
>>
>>You probably already know this, but you can disregard this about cam tower
>>shims.....
>>you don't have the alignment problems to deal with on an ohv engine.
>>
>>Joseph
>>
>
>
>
>
>
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