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Help - Install New HEI Distributor [message #308030] Thu, 29 September 2016 20:48 Go to next message
Steve is currently offline  Steve   United States
Messages: 506
Registered: September 2013
Location: East Greenville, Pa
Karma: 1
Senior Member
I have installed at least a dozen HEI units in small and big block chevy motors but can't seem to get this Oldsmobile distributor in. I can grab any tooth with the old distributor and turn it down into position. With my new Dick Paterson distributor it feels like it is going in but then seems to bottom out just before it seats with the intake manifold. I have tried turning the oil pump drive shaft in small increments thinking that maybe the gear on the new distributor aligns a little differently. No luck. It seems that no matter where I turn the oil pump drive shaft the old distributor will just drop right into place but the new one will not quite seat so that it is all the way down and the rotor lines up with the number 1 spark plug wire.

Any thoughts would be appreciated. Trying to make it to the GMC rally in Ohio.

Also the oil drive shaft is a little different than the Chevy. Looks like a hexagon vs. a slot.

I am a bookkeeper, not a mechanic.


1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
Re: [GMCnet] Help - Install New HEI Distributor [message #308032 is a reply to message #308030] Thu, 29 September 2016 21:05 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
Messages: 1501
Registered: October 2011
Location: La Grange, Wyoming
Karma: 5
Senior Member
Are the distributor drive teeth the same. Gear helix angle the same , same
number of teeth, distributor shaft the same length? What is different
between the two distributors?

On Thu, Sep 29, 2016 at 7:48 PM, Steve Adams wrote:

> I have installed at least a dozen HEI units in small and big block chevy
> motors but can't seem to get this Oldsmobile distributor in. I can grab any
> tooth with the old distributor and turn it down into position. With my
> new Dick Paterson distributor it feels like it is going in but then seems to
> bottom out just before it seats with the intake manifold. I have tried
> turning the oil pump drive shaft in small increments thinking that maybe the
> gear on the new distributor aligns a little differently. No luck. It
> seems that no matter where I turn the oil pump drive shaft the old
> distributor
> will just drop right into place but the new one will not quite seat so
> that it is all the way down and the rotor lines up with the number 1 spark
> plug
> wire.
>
> Any thoughts would be appreciated. Trying to make it to the GMC rally in
> Ohio.
>
> Also the oil drive shaft is a little different than the Chevy. Looks like
> a hexagon vs. a slot.
>
> I am a bookkeeper, not a mechanic.
> --
> 1978 GMC Royal
> Eastern Pennslyvania
> 1968 Chevrolet C20 396 Camper Special
> 1969 Chevrolet C20 Camper Special
> 1985 Buick Electra Park Avenue
> 1992 Camaro 25th Anniversary Heretage Edition Black
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: Help - Install New HEI Distributor [message #308033 is a reply to message #308030] Thu, 29 September 2016 21:16 Go to previous messageGo to next message
Steve is currently offline  Steve   United States
Messages: 506
Registered: September 2013
Location: East Greenville, Pa
Karma: 1
Senior Member
Bruce, I will compare a little closer. At first glance they looked the same. I also have a lot of confidence in Dick Patterson. I doubt he would build and send something that is incompatible. At first I was sure I just needed to adjust the oil pump drive shaft as I have had to do on Chevy V8 motors. This one feels like it is solidly bottoming out on something. Seems to be internal as there is plenty of clearance around the outside of the distributor. I am going to go try it again and then check back here.

Thanks for the input Bruce.


1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
Re: [GMCnet] Help - Install New HEI Distributor [message #308034 is a reply to message #308032] Thu, 29 September 2016 21:09 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
Steve
Since you say its a new Dick Paterson distributor why don’t you call Dick to discuss the problem.
If you need his phone number let me know.


Emery Stora
77 Kingsley
Frederick, CO
> On Sep 29, 2016, at 10:05 PM, Bruce Hart wrote:
>
> Are the distributor drive teeth the same. Gear helix angle the same , same
> number of teeth, distributor shaft the same length? What is different
> between the two distributors?
>
> On Thu, Sep 29, 2016 at 7:48 PM, Steve Adams wrote:
>
>> I have installed at least a dozen HEI units in small and big block chevy
>> motors but can't seem to get this Oldsmobile distributor in. I can grab any
>> tooth with the old distributor and turn it down into position. With my
>> new Dick Paterson distributor it feels like it is going in but then seems to
>> bottom out just before it seats with the intake manifold. I have tried
>> turning the oil pump drive shaft in small increments thinking that maybe the
>> gear on the new distributor aligns a little differently. No luck. It
>> seems that no matter where I turn the oil pump drive shaft the old
>> distributor
>> will just drop right into place but the new one will not quite seat so
>> that it is all the way down and the rotor lines up with the number 1 spark
>> plug
>> wire.
>>
>> Any thoughts would be appreciated. Trying to make it to the GMC rally in
>> Ohio.
>>
>> Also the oil drive shaft is a little different than the Chevy. Looks like
>> a hexagon vs. a slot.
>>
>> I am a bookkeeper, not a mechanic.
>> --
>> 1978 GMC Royal
>> Eastern Pennslyvania
>> 1968 Chevrolet C20 396 Camper Special
>> 1969 Chevrolet C20 Camper Special
>> 1985 Buick Electra Park Avenue
>> 1992 Camaro 25th Anniversary Heretage Edition Black
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Bruce Hart
> 1976 Palm Beach
> Milliken, Co
> GMC=Got More Class
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: Help - Install New HEI Distributor [message #308035 is a reply to message #308030] Thu, 29 September 2016 21:54 Go to previous messageGo to next message
Steve is currently offline  Steve   United States
Messages: 506
Registered: September 2013
Location: East Greenville, Pa
Karma: 1
Senior Member
Thank You Bruce,

I broke out the micrometer and compared measurements between old and new distributor. As it turns out, the new O ring was considerably proud of the grove and preventing the distributor from going in all the way. I lubed it up with some Mobil 1 and then applied some even downward pressure and it snapped into place.

Like I said, bookkeeper not mechanic.

Thanks again Bruce.

I remember a few years ago very early on in my GMC ownership Bruce sold me a spare tire carrier at a reasonable price. He is a good GMC'r in my book. I hope to pay it forward where and when I can.


1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
Re: [GMCnet] Help - Install New HEI Distributor [message #308039 is a reply to message #308035] Thu, 29 September 2016 22:22 Go to previous messageGo to next message
sgltrac is currently offline  sgltrac   United States
Messages: 2797
Registered: April 2011
Karma: 1
Senior Member
Love your disclaimer Steve.

Sully

On Thursday, September 29, 2016, Steve Adams wrote:

> Thank You Bruce,
>
> I broke out the micrometer and compared measurements between old and new
> distributor. As it turns out, the new O ring was considerably proud of the
> grove and preventing the distributor from going in all the way. I lubed
> it up with some Mobil 1 and then applied some even downward pressure and it
> snapped into place.
>
> Like I said, bookkeeper not mechanic.
>
> Thanks again Bruce.
>
> I remember a few years ago very early on in my GMC ownership Bruce sold me
> a spare tire carrier at a reasonable price. He is a good GMC'r in my book.
> I hope to pay it forward where and when I can.
> --
> 1978 GMC Royal
> Eastern Pennslyvania
> 1968 Chevrolet C20 396 Camper Special
> 1969 Chevrolet C20 Camper Special
> 1985 Buick Electra Park Avenue
> 1992 Camaro 25th Anniversary Heretage Edition Black
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.
Re: [GMCnet] Help - Install New HEI Distributor [message #308046 is a reply to message #308034] Fri, 30 September 2016 10:38 Go to previous messageGo to next message
Steve is currently offline  Steve   United States
Messages: 506
Registered: September 2013
Location: East Greenville, Pa
Karma: 1
Senior Member
Thanks Emery,

I didn't want to call because it was getting late. I guess I am just learning the subtle differences between the Oldsmobile and Chevrolet engines. Although I got it in, it did not solve my loss of power issues. I am going to post another thread on that.


1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
Re: [GMCnet] Help - Install New HEI Distributor [message #308047 is a reply to message #308046] Fri, 30 September 2016 11:05 Go to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Olds engines turn the Camshaft distributor gear the opposite way from
Chevrolet. The oil pump drive shaft in an Olds engine is a hexagon shaft,
and is retained by two spring clips placed on a snap ring groove in the
lower part of the shaft where it enters the oil pump. Normally, it cannot
be removed from the distributor hole, but, the shaft can get stuck in the
bottom of the distributor drive gear making the distributor difficult to
remove. If brute force is used to remove the distributor, the spring clips
can slide down the shaft and the whole assembly will come out the top,
leaving the clips to find their way into the bottom of the oil pan, or
someplace far worse. Just another difference between Olds engines and other
GM products. Not necessarily better, just different from Chevrolet. Lots of
other "little" differences in them also.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Fri, Sep 30, 2016 at 8:38 AM, Steve Adams wrote:

> Thanks Emery,
>
> I didn't want to call because it was getting late. I guess I am just
> learning the subtle differences between the Oldsmobile and Chevrolet
> engines.
> Although I got it in, it did not solve my loss of power issues. I am
> going to post another thread on that.
> --
> 1978 GMC Royal
> Eastern Pennslyvania
> 1968 Chevrolet C20 396 Camper Special
> 1969 Chevrolet C20 Camper Special
> 1985 Buick Electra Park Avenue
> 1992 Camaro 25th Anniversary Heretage Edition Black
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
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Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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