1966 chevy engine oil leak fix plan

I have a 1966 Chevy II with a 6 cylinder engine in it. The engine has
some small oil leaks that I want to correct. It's been over 30 years
since I last rebuilt an engine and I don't recall the details of that
effort. Of course good ol Dad was there then too. I'm most curious about
how to correct the rear seal of the crankshaft. Below I've listed my
plans and some questions I already have.

Please advise me on gasket selection, procedure and anything else you
think would help.


Planned Gaskets/Seals to be replaced.
1. Gasket for valve cover.
2. Gasket for fuel pump.
3. Gasket for timing chain cover.
4. Seal in timing chain cover for harmonic balance/crankshaft.
5. Gasket for oil pan.
5. Seal at rear of crankshaft.


Questions.
1. Regarding the Seal, for the harmonic balance, in the timing chain cover,
a. should I precoat the seal-harmonic balance mating surface with
anything during assembly?
b. is a glue/sealant applied to the seal-timing cover mating surface
during assembly?

2. Regarding the Seal at the rear of the crankshaft,
a. can this be easily replaced? I'm suspecting that replacing this
would require loosening the bearing journals holding the crankshaft in
the block and that would be too risky.


Thanks,
Charlie

Charlie wrote:
> I have a 1966 Chevy II with a 6 cylinder engine in it. The engine has
> some small oil leaks that I want to correct. It's been over 30 years
> since I last rebuilt an engine and I don't recall the details of that
> effort. Of course good ol Dad was there then too. I'm most curious about
> how to correct the rear seal of the crankshaft. Below I've listed my
> plans and some questions I already have.
>
> Please advise me on gasket selection, procedure and anything else you
> think would help.
>
>

First step: obtain and read dervice manual.

Second, follow procedure therein.

In article <O6pvg.12791$6w.7721@fed1read11>,
Charlie > wrote:

<snip>

> Questions.
> 1. Regarding the Seal, for the harmonic balance, in the timing chain cover,
> a. should I precoat the seal-harmonic balance mating surface with
> anything during assembly?

Yes. Motor oil.
If the snout of the harmonic balancer has a groove worn in it,
install a speedy sleeve.

> b. is a glue/sealant applied to the seal-timing cover mating surface
> during assembly?

Depends on the seal. Some come with a bead of sealer already
applied, if not, I'd use #2 Permatex.
>
> 2. Regarding the Seal at the rear of the crankshaft,
> a. can this be easily replaced?

Depends on your definition of easy.

> I'm suspecting that replacing this
> would require loosening the bearing journals holding the crankshaft in
> the block and that would be too risky.

If the original/replacement seal is a rope seal, loosening the
crank and allowing it to drop can make things easier, the crank
won't drop until the transmission is disconnected though. Not a
big deal if it's an automatic, bigger deal if it's a manual trans.
If a rubber seal, they go in and out pretty easy.

Nothing risky about dropping a crankshaft a few thousandths, man
put it together, man can take it apart.

aarcuda69062 wrote:
> In article <O6pvg.12791$6w.7721@fed1read11>,
> Charlie > wrote:
>
> <snip>
>
> > Questions.
> > 1. Regarding the Seal, for the harmonic balance, in the timing chain cover,
> > a. should I precoat the seal-harmonic balance mating surface with
> > anything during assembly?
>
> Yes. Motor oil.
> If the snout of the harmonic balancer has a groove worn in it,
> install a speedy sleeve.
>
> > b. is a glue/sealant applied to the seal-timing cover mating surface
> > during assembly?
>
> Depends on the seal. Some come with a bead of sealer already
> applied, if not, I'd use #2 Permatex.
> >
> > 2. Regarding the Seal at the rear of the crankshaft,
> > a. can this be easily replaced?
>
> Depends on your definition of easy.
>
> > I'm suspecting that replacing this
> > would require loosening the bearing journals holding the crankshaft in
> > the block and that would be too risky.
>
> If the original/replacement seal is a rope seal, loosening the
> crank and allowing it to drop can make things easier, the crank
> won't drop until the transmission is disconnected though. Not a
> big deal if it's an automatic, bigger deal if it's a manual trans.
> If a rubber seal, they go in and out pretty easy.

You do not drop the trans !

>
> Nothing risky about dropping a crankshaft a few thousandths, man
> put it together, man can take it apart.

In article
. com>,
wrote:

> aarcuda69062 wrote:
> > In article <O6pvg.12791$6w.7721@fed1read11>,
> > Charlie > wrote:
> >
> > <snip>
> >
> > > Questions.
> > > 1. Regarding the Seal, for the harmonic balance, in the timing chain
> > > cover,
> > > a. should I precoat the seal-harmonic balance mating surface with
> > > anything during assembly?
> >
> > Yes. Motor oil.
> > If the snout of the harmonic balancer has a groove worn in it,
> > install a speedy sleeve.
> >
> > > b. is a glue/sealant applied to the seal-timing cover mating surface
> > > during assembly?
> >
> > Depends on the seal. Some come with a bead of sealer already
> > applied, if not, I'd use #2 Permatex.
> > >
> > > 2. Regarding the Seal at the rear of the crankshaft,
> > > a. can this be easily replaced?
> >
> > Depends on your definition of easy.
> >
> > > I'm suspecting that replacing this
> > > would require loosening the bearing journals holding the crankshaft in
> > > the block and that would be too risky.
> >
> > If the original/replacement seal is a rope seal, loosening the
> > crank and allowing it to drop can make things easier, the crank
> > won't drop until the transmission is disconnected though. Not a
> > big deal if it's an automatic, bigger deal if it's a manual trans.
> > If a rubber seal, they go in and out pretty easy.
>
> You do not drop the trans !

They don't bounce very well?

aarcuda69062 wrote:
> In article
> . com>,
> wrote:
>
> > aarcuda69062 wrote:
> > > In article <O6pvg.12791$6w.7721@fed1read11>,
> > > Charlie > wrote:
> > >
> > > <snip>
> > >
> > > > Questions.
> > > > 1. Regarding the Seal, for the harmonic balance, in the timing chain
> > > > cover,
> > > > a. should I precoat the seal-harmonic balance mating surface with
> > > > anything during assembly?
> > >
> > > Yes. Motor oil.
> > > If the snout of the harmonic balancer has a groove worn in it,
> > > install a speedy sleeve.
> > >
> > > > b. is a glue/sealant applied to the seal-timing cover mating surface
> > > > during assembly?
> > >
> > > Depends on the seal. Some come with a bead of sealer already
> > > applied, if not, I'd use #2 Permatex.
> > > >
> > > > 2. Regarding the Seal at the rear of the crankshaft,
> > > > a. can this be easily replaced?
> > >
> > > Depends on your definition of easy.
> > >
> > > > I'm suspecting that replacing this
> > > > would require loosening the bearing journals holding the crankshaft in
> > > > the block and that would be too risky.
> > >
> > > If the original/replacement seal is a rope seal, loosening the
> > > crank and allowing it to drop can make things easier, the crank
> > > won't drop until the transmission is disconnected though. Not a
> > > big deal if it's an automatic, bigger deal if it's a manual trans.
> > > If a rubber seal, they go in and out pretty easy.
> >
> > You do not drop the trans !

LOL

> They don't bounce very well?

Thanks for the reply.

The engine will be out of the car and seperated from the transmission
and clutch assembly.

If I loosen the main being journals of the crank to make space for
replacing the rear seal does that create a large risk of future main
bearing problems?

Charlie

aarcuda69062 wrote:
> In article <O6pvg.12791$6w.7721@fed1read11>,
> Charlie > wrote:
>
> <snip>
>
>>Questions.
>>1. Regarding the Seal, for the harmonic balance, in the timing chain cover,
>> a. should I precoat the seal-harmonic balance mating surface with
>>anything during assembly?
>
>
> Yes. Motor oil.
> If the snout of the harmonic balancer has a groove worn in it,
> install a speedy sleeve.
>
>
>> b. is a glue/sealant applied to the seal-timing cover mating surface
>>during assembly?
>
>
> Depends on the seal. Some come with a bead of sealer already
> applied, if not, I'd use #2 Permatex.
>
>>2. Regarding the Seal at the rear of the crankshaft,
>> a. can this be easily replaced?
>
>
> Depends on your definition of easy.
>
>
>>I'm suspecting that replacing this
>>would require loosening the bearing journals holding the crankshaft in
>>the block and that would be too risky.
>
>
> If the original/replacement seal is a rope seal, loosening the
> crank and allowing it to drop can make things easier, the crank
> won't drop until the transmission is disconnected though. Not a
> big deal if it's an automatic, bigger deal if it's a manual trans.
> If a rubber seal, they go in and out pretty easy.
>
> Nothing risky about dropping a crankshaft a few thousandths, man
> put it together, man can take it apart.

Since you're already doing the work of pulling the motor and getting it on
a stand, and since you're pulling the pan and timing cover anyway to replace
gaskets, what better opportunity to put in new rod / main bearings, oil
pump, and timing set. Those parts are relatively inexpensive - should go
less than $150 - and if you do it, you'll be sure of the bottom end for
years to come.

If you decide not to go that route, and just replace the seals and gaskets,
the operative word is cleanliness. Before cracking the mains caps, be sure
everything is spotlessly clean, to avoid the chance of any particles getting
trapped between the crank and bearings.

And ditto on the balancer repair sleeve - on an engine of that vintage, its
almost certain that the soft iron snout of the balancer will have a groove
in it. The last two I built, a 77 4bolt main 350, and an 85 4.3 v6 both had
worn balancers.

--
V8Z
Chevy V6 powered '66 Datsun Roadster
http://www.mildevco.net/chevypowereddatsuns/
Chevy V8 powered '77 Datsun 280Z
http://www.mildevco.net/chevypowereddatsuns/


"Charlie" > wrote in message
news:skDvg.12807$6w.7575@fed1read11...
> Thanks for the reply.
>
> The engine will be out of the car and seperated from the transmission
> and clutch assembly.
>
> If I loosen the main being journals of the crank to make space for
> replacing the rear seal does that create a large risk of future main
> bearing problems?
>
> Charlie
>
> aarcuda69062 wrote:
> > In article <O6pvg.12791$6w.7721@fed1read11>,
> > Charlie > wrote:
> >
> > <snip>

Cool thread.

Alvin in AZ ('75 F150 360 T-18)