distributor looens up

General engine tech -- Drag Racing to Circle Track

Moderator: Team

1980RS
Guru
Guru
Posts: 1636
Joined: Thu Oct 13, 2016 10:03 am
Location:

Re: distributor looens up

Post by 1980RS »

Like others have said, take out the distributor and see if it bottoms out on the intake, if it does not I don't care what you try it will move around.
77cruiser
Guru
Guru
Posts: 1484
Joined: Fri Dec 29, 2006 10:32 pm
Location: I Falls MN
Contact:

Re: distributor looens up

Post by 77cruiser »

If it does bottom out, how long before it ruins the oil pump?
Jim
Tuner
Guru
Guru
Posts: 3184
Joined: Sun Apr 01, 2007 5:26 am
Location:

Re: distributor looens up

Post by Tuner »

Not long, as anyone who ever mixed the early Chevy II short oil pump with a regular intermediate shaft found out.
chevyart
New Member
New Member
Posts: 39
Joined: Sun Aug 23, 2020 2:13 pm
Location:

Re: distributor looens up

Post by chevyart »

thanks for all the inputs to my dilema. gonna take the dist out and just look at clearance between gear and housing(think that was checked at engine install and i will check the gear for wear (bronze gear) and i will do the test to make sure the distributor fall all the way down with out the gasket, i tend to go with what schurkey said and even morso with what Tuner














said. tuners words were exactly what a well known stock-superstock engine builder just told me recently about the upward pressure from cam gear etc,. to update this, just yesterday i went over to get ready to remove distributor and i noticed oil on bottom of distributor at gasket . that tells me the distributor had a little help spinning loose(lubrication), i have a new lockdown with a stud just in case the old one was not doing the job(that one was also mounted on a stud.. one other thing to bring to light.. years ago one of the mags always did tech talk and they said the old chevy hold downs were the best ever made as GM actually did research and development on even small items as dist hold downs, air cleaners, etc.i will also make a little mark on distributor and a corresponding mark on intake after i time the engine and i will check it often to see if it moves. thanks for all the input and i for sure will repost after i fix the problem and say what i think the problem was for sure.. this is the best site for knowledgeable hot rod info. Art Peterson in NY
bill jones
Guru
Guru
Posts: 2649
Joined: Sun Sep 05, 2004 6:38 pm
Location: salt lake city, ut
Contact:

Re: distributor looens up

Post by bill jones »

---while you have the distributor out---and the distributor gasket removed---the distributor should fit down flat and flush on top of the manifolds circular pad
---and the upper distributor rotor end should still have whatever normal end play it has--something like .008" to maybe as loose as .030" up and down movement without the gasket

---but---often that circular pad is not flat to the underside of the distributor flange---all the way around

---so you can use some Dykem or marking pen to color up that pad
---then twist the distributor down and rotate it back and forth
---and remove the distributor to see where high rub spot is on the manifold hole pad

---once you find the high rub spot you can drop the distributor back in and try thin feeler gauge at the gasket surface to see how much tilt that pad is off
---probably like .008" is about all a NEW gasket might be able to compress and not leak

--any more than that for sure will require the pad to be re-machined
User avatar
MadBill
Guru
Guru
Posts: 15024
Joined: Tue Nov 15, 2005 10:41 am
Location: The Great White North

Re: distributor looens up

Post by MadBill »

There is another possibility, one that I experienced decades back with a friend's 455 Buick: the drive gear roll pin sheared, allowing the shaft to shift a few degrees... #-o
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
chevyart
New Member
New Member
Posts: 39
Joined: Sun Aug 23, 2020 2:13 pm
Location:

Re: distributor looens up

Post by chevyart »

now that scares me mad bill. im gonna remove distributor and check out the whole distributor. appreciate all the input. i will report back after i complete the removal and inspection of the distributor. thanks Art in NY
dfarr67
Expert
Expert
Posts: 860
Joined: Sat Jul 27, 2013 7:14 pm
Location:

Re: distributor looens up

Post by dfarr67 »

With new engine machining I had an issue with a sbc and one dizzy gasket- when tightened down the oil pump got loaded and it pushed the spur gear into the cove plate- squealed when hot, installed a couple more gaskets and was ok.
1980RS
Guru
Guru
Posts: 1636
Joined: Thu Oct 13, 2016 10:03 am
Location:

Re: distributor looens up

Post by 1980RS »

dfarr67 wrote: Wed Jun 16, 2021 8:45 am With new engine machining I had an issue with a sbc and one dizzy gasket- when tightened down the oil pump got loaded and it pushed the spur gear into the cove plate- squealed when hot, installed a couple more gaskets and was ok.
Hench the reason for the MSD distributor with the adjustable collar to fix that problem. The problems like that I have had were from poor machining of the the distributor hole being cut too deep on the intake manifold.
Schurkey
HotPass
HotPass
Posts: 1858
Joined: Sun Mar 01, 2009 2:42 am
Location: The Seasonally Frozen Wastelands

Re: distributor looens up

Post by Schurkey »

MadBill wrote: Fri Jun 11, 2021 9:09 pm There is another possibility, one that I experienced decades back with a friend's 455 Buick: the drive gear roll pin sheared, allowing the shaft to shift a few degrees... #-o
Common on Buicks, not so common on the other engine families. Buick used thin roll-pins.
User avatar
MadBill
Guru
Guru
Posts: 15024
Joined: Tue Nov 15, 2005 10:41 am
Location: The Great White North

Re: distributor looens up

Post by MadBill »

Yes; we drilled out the hole for a 3/16" pin from 1/8th(?).
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
User avatar
Baprace
HotPass
HotPass
Posts: 1905
Joined: Sun Aug 06, 2006 4:57 am
Location: Henrietta NY 14623

Re: distributor looens up

Post by Baprace »

Chevy you have mail.
allencr267
Pro
Pro
Posts: 362
Joined: Wed Nov 07, 2012 6:28 pm
Location: Tallahassee Florida USofA

Re: distributor looens up

Post by allencr267 »

He's setting it, the housing cause it's loose, back in the same place, not resetting it to a different place like if the shaft & gear un-aligned, right?
Post Reply