Another project (timing chain) going amok.

H

heinz wittenbecher

New member
Mar 1, 1998
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Well... ordered my stuff from Mondello today for the timing chain project.
Also ordered cam, water pump and restrictor kit. Don't know If I'll do the
camshaft or restrictor, but thought I'd get the parts just in case.

Asked about oilpan removal while engine still in coach... nope.

For the info of other Canuck GMCers... was quoted C$231 locally for the
Cloyes. Makes 89+exchange+GST still look good.

Also found a what was supposed to be a "White Box" Cloyes TC for 69.99 but
decided to go with Mondello. Not quite comfortable with the JC Whitney
specials. Thanks for all the suggestions, leads, etc.

Heinz
'76 Transmode
 
Heinz you made the right choice and now I will tell you why in my opinion.

In Joe Mondello's Technical reference manual, page 9 he talks about timing
chains.

"the biggest problems I have come to notice in the last few years has been
with the timing chain sets. Many major distributers and manufacturers are
buying chain sets from china, Taiwan and Korea. These chain sets, in most
cases are inaccurate. I did some comparison shopping after receiving calls
from customers with timing problems. First, I bought a roller chain set
that sold between $24.95 and $49.95 (brand name), than purchased 5 more
chain sets and compared them against one of our Cloyes True Roller chain
sets. Well out of 6 sets, 4 of them were so far off between the opening and
closing specs, plus where the o ring timing marks were in relation to the
T.D.C. were also off. One chain set was 12 degrees retarded at the valve
opening side and dead-on on the valve closing side, this my friends, was
also a brand name you would have trusted.. etc"

Bottom line is that MOndello sells Cloyes chains in .005", .010", and .015"
over for engines that need them. Does that tell you how accurate these
chains have to be?

Heinz you and I appear to think alike when it comes to buying parts we put
in. buy the best. You pay a little more but get the results you should.

>Well... ordered my stuff from Mondello today for the timing chain project.
>Also ordered cam, water pump and restrictor kit. Don't know If I'll do the
>camshaft or restrictor, but thought I'd get the parts just in case.
>
>Asked about oilpan removal while engine still in coach... nope.
>
>For the info of other Canuck GMCers... was quoted C$231 locally for the
>Cloyes. Makes 89+exchange+GST still look good.
>
>Also found a what was supposed to be a "White Box" Cloyes TC for 69.99 but
>decided to go with Mondello. Not quite comfortable with the JC Whitney
>specials. Thanks for all the suggestions, leads, etc.
>
>Heinz
>'76 Transmode
>
>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
>Heinz you made the right choice and now I will tell you why in my opinion.
>

Thanks for 'vote of confidence' and the note I snipped to keep the archives
shorter.

I ordered the tech manual too of course.

One thing I'm confused on is the Cam though. When the TechGuy suggested the
cam I specifically asked if moere stuff has to removed or if I have it all
apart (or close to) anyways. He said it was already to be able to change cam
when I went as far as timing chain. That didn't quite sound right so I
perused the Manual some... seems to chnage cam you pretty well have to have
the engine out or at least the radiator and intale manifold off, etc. etc.

I'm hoping that changing the timing chain will only require removel of
waterpump, front cover and front stuff, i.e. no intake manifold removal or
anything else from 'the top'. I sure hope I'm right. I won't mind if he is
right if nothing from the top has to removed, but at moment I'm more than a
little confused.

Will probably be even more confused when starting the project for real :-)

Heinz
 
He is incorrect. You do have to remove the intake to replace the cam.
However you can replace the timing chain and two gears by only jacking a
little on the front of the engine (the front motor mount has to be
disconnected), and than removing the items you noted. The job is pretty
straight forward and directions will probably come with the chain. If you
have not received your tech manual by the time you get the chain, e-mail me
and I will scan pages of the manual and send to you.

>
>
>>Heinz you made the right choice and now I will tell you why in my opinion.
>>
>
>Thanks for 'vote of confidence' and the note I snipped to keep the archives
>shorter.
>
>I ordered the tech manual too of course.
>
>One thing I'm confused on is the Cam though. When the TechGuy suggested the
>cam I specifically asked if moere stuff has to removed or if I have it all
>apart (or close to) anyways. He said it was already to be able to change cam
>when I went as far as timing chain. That didn't quite sound right so I
>perused the Manual some... seems to chnage cam you pretty well have to have
>the engine out or at least the radiator and intale manifold off, etc. etc.
>
>I'm hoping that changing the timing chain will only require removel of
>waterpump, front cover and front stuff, i.e. no intake manifold removal or
>anything else from 'the top'. I sure hope I'm right. I won't mind if he is
>right if nothing from the top has to removed, but at moment I'm more than a
>little confused.
>
>Will probably be even more confused when starting the project for real :-)
>
>Heinz
>
>
>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
>He is incorrect. You do have to remove the intake to replace the cam.

That's what I thought...
It this type of comment by the "experts" we rely on that keeps me wondering
and concerned. It either means they don't know or didn't listen... both very
disheartening.

Heinz.

>However you can replace the timing chain and two gears by only jacking a
>little on the front of the engine (the front motor mount has to be
>disconnected), and than removing the items you noted. The job is pretty
>straight forward and directions will probably come with the chain. If you
>have not received your tech manual by the time you get the chain, e-mail me
>and I will scan pages of the manual and send to you.
>
>

>>
>>
>>>Heinz you made the right choice and now I will tell you why in my
opinion.
>>>
>>
>>Thanks for 'vote of confidence' and the note I snipped to keep the
archives
>>shorter.
>>
>>I ordered the tech manual too of course.
>>
>>One thing I'm confused on is the Cam though. When the TechGuy suggested
the
>>cam I specifically asked if moere stuff has to removed or if I have it all
>>apart (or close to) anyways. He said it was already to be able to change
cam
>>when I went as far as timing chain. That didn't quite sound right so I
>>perused the Manual some... seems to chnage cam you pretty well have to
have
>>the engine out or at least the radiator and intale manifold off, etc. etc.
>>
>>I'm hoping that changing the timing chain will only require removel of
>>waterpump, front cover and front stuff, i.e. no intake manifold removal or
>>anything else from 'the top'. I sure hope I'm right. I won't mind if he is
>>right if nothing from the top has to removed, but at moment I'm more than
a
>>little confused.
>>
>>Will probably be even more confused when starting the project for real :-)
>>
>>Heinz
>>
>>
>>
>>
>>
>Tom & Marg Warner
>Vernon Center NY
>1976 palmbeach
>"The beautiful Mohawk Vally"
>
>
 
With your permission I would like to talk to Joe about this. this type of
service is not accepted by him. He takes great pride in being called Dr.
Olds, and is looked upon by those in the know as being THE authority on the
olds engines.

If you had tried to remove the cam, it would not have come out unless you
had really hauled on it, and than you would have broke something. The
rockers and springs put a lot of force on the hydraulic lifters and would
have broke something.

>
>
>>He is incorrect. You do have to remove the intake to replace the cam.
>
>That's what I thought...
>It this type of comment by the "experts" we rely on that keeps me wondering
>and concerned. It either means they don't know or didn't listen... both very
>disheartening.
>
>Heinz.
>
>
>>However you can replace the timing chain and two gears by only jacking a
>>little on the front of the engine (the front motor mount has to be
>>disconnected), and than removing the items you noted. The job is pretty
>>straight forward and directions will probably come with the chain. If you
>>have not received your tech manual by the time you get the chain, e-mail me
>>and I will scan pages of the manual and send to you.
>>
>>

>>>
>>>
>>>>Heinz you made the right choice and now I will tell you why in my
>opinion.
>>>>
>>>
>>>Thanks for 'vote of confidence' and the note I snipped to keep the
>archives
>>>shorter.
>>>
>>>I ordered the tech manual too of course.
>>>
>>>One thing I'm confused on is the Cam though. When the TechGuy suggested
>the
>>>cam I specifically asked if moere stuff has to removed or if I have it all
>>>apart (or close to) anyways. He said it was already to be able to change
>cam
>>>when I went as far as timing chain. That didn't quite sound right so I
>>>perused the Manual some... seems to chnage cam you pretty well have to
>have
>>>the engine out or at least the radiator and intale manifold off, etc. etc.
>>>
>>>I'm hoping that changing the timing chain will only require removel of
>>>waterpump, front cover and front stuff, i.e. no intake manifold removal or
>>>anything else from 'the top'. I sure hope I'm right. I won't mind if he is
>>>right if nothing from the top has to removed, but at moment I'm more than
>a
>>>little confused.
>>>
>>>Will probably be even more confused when starting the project for real :-)
>>>
>>>Heinz
>>>
>>>
>>>
>>>
>>>
>>Tom & Marg Warner
>>Vernon Center NY
>>1976 palmbeach
>>"The beautiful Mohawk Vally"
>>
>>
>
>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
>
> He is incorrect. You do have to remove the intake to replace the cam.

Probably have to drop the radiator to have enough room to slide the cam
out too. Usually best to wait for overhaul time to change cams. It's
easy to mess up the cam bearings sliding the cam back in if you don't
have open access to the front of the engine.

Can be done tho' - back in my teen years, I had a friend with a 69
Chevelle SS 396. I think he changed cams more often than socks. He
would pull the intake, remove the radiator and drop the a/c condenser
down. Finally got it down to where he could do the swap in about four
hours! BTW, he still has that Chevelle and it's in "mint" condition!
Worth a couple bucks I imagine.

Patrick
- --
Patrick Flowers
Mailto:patrick

The GMC Motorhome Page
http://www.gmcmotorhome.com
 
Go for it.
I asked about "what else while in there" and the cam was mentioned.
I then specifically asked if I would have it all off anyways for the timing
chain I was told yes, hence I ordered the cam just in case he was right,
even though I had my doubts even then :-)

Heinz

>With your permission I would like to talk to Joe about this. this type of
>service is not accepted by him. He takes great pride in being called Dr.
>Olds, and is looked upon by those in the know as being THE authority on the
>olds engines.
>
>If you had tried to remove the cam, it would not have come out unless you
>had really hauled on it, and than you would have broke something. The
>rockers and springs put a lot of force on the hydraulic lifters and would
>have broke something.
>
>

>>
>>
>>>He is incorrect. You do have to remove the intake to replace the cam.
>>
>>That's what I thought...
>>It this type of comment by the "experts" we rely on that keeps me
wondering
>>and concerned. It either means they don't know or didn't listen... both
very
>>disheartening.
>>
>>Heinz.
>>
>>
>>>However you can replace the timing chain and two gears by only jacking a
>>>little on the front of the engine (the front motor mount has to be
>>>disconnected), and than removing the items you noted. The job is pretty
>>>straight forward and directions will probably come with the chain. If
you
>>>have not received your tech manual by the time you get the chain, e-mail
me
>>>and I will scan pages of the manual and send to you.
>>>
>>>

>>>>
>>>>
>>>>>Heinz you made the right choice and now I will tell you why in my
>>opinion.
>>>>>
>>>>
>>>>Thanks for 'vote of confidence' and the note I snipped to keep the
>>archives
>>>>shorter.
>>>>
>>>>I ordered the tech manual too of course.
>>>>
>>>>One thing I'm confused on is the Cam though. When the TechGuy suggested
>>the
>>>>cam I specifically asked if moere stuff has to removed or if I have it
all
>>>>apart (or close to) anyways. He said it was already to be able to change
>>cam
>>>>when I went as far as timing chain. That didn't quite sound right so I
>>>>perused the Manual some... seems to chnage cam you pretty well have to
>>have
>>>>the engine out or at least the radiator and intale manifold off, etc.
etc.
>>>>
>>>>I'm hoping that changing the timing chain will only require removel of
>>>>waterpump, front cover and front stuff, i.e. no intake manifold removal
or
>>>>anything else from 'the top'. I sure hope I'm right. I won't mind if he
is
>>>>right if nothing from the top has to removed, but at moment I'm more
than
>>a
>>>>little confused.
>>>>
>>>>Will probably be even more confused when starting the project for real
:-)
>>>>
>>>>Heinz
>>>>
>>>>
>>>>
>>>>
>>>>
>>>Tom & Marg Warner
>>>Vernon Center NY
>>>1976 palmbeach
>>>"The beautiful Mohawk Vally"
>>>
>>>
>>
>>
>>
>>
>Tom & Marg Warner
>Vernon Center NY
>1976 palmbeach
>"The beautiful Mohawk Vally"
>
>
 
The camshaft can be easily replaced by removing the intake, pushrods,
and lifters but there is something else to consider. When you replace a
camshaft without replacing the cam bearings, you have new cam journals
running on old cam bearings. This will generally cause excessive cam
bearing wear which can result in significantly lower oil pressure,
especially in a higher mileage engine. In my opinion, I would replace
the cam this way only if the old one was badly worn and had to be
changed, not just to optimize performance. The time to update to a more
modern cam is during rebuild when the cam bearings can be changed also.

Lorry
GMC Wannabe

- --

Please visit our website at:
http://www.intellsearch.com
 
>The camshaft can be easily replaced by removing the intake, pushrods,
>and lifters but there is something else to consider.

And probably the radiator...
The only reason I had considered it was due to the reply I received from the
"expert" as to what else could/should be done while things were open for
timing chain replacement.
As I think that advice was completely off-base the project remains as it was
originally intended... timing chain, water pump, etc.



BTW, has anyone done the TC as a do-it-youself project?
How close is actual to the service manual?
How did you support the front of the engine while removing Timing Cover?

TIA - Heinz
 
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