Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rating: Thread Rating: 12 votes, 4.00 average.
Author
Thread Post New Thread    Reply
Somatic Negative Optimist
 
Gunter's Avatar
 
Join Date: Mar 2002
Location: Winlaw, BC, Canada
Posts: 7,206
Garage
I strongly recommend that you check the curve in situ with a strobe light at various RPM's.
Start with the basic 5 deg BTDC ~900 RPM. Then connect the vacuum. There should be no change but as soon as you come off idle, the advance should be noticable.
Record the degrees for all RPM's right up to 6000 were it ends at ~30-33 deg.
Let us know what you get.

__________________
1980 Carrerarized SC with SS 3.2, LSD & Extras. SOLD!
1995 seafoam-green 993 C2, LSD, Sport seats.
Abstract Darwin Ipso Facto: "Life is evolutionary random and has no meaning as evidenced by 7 Billion paranoid talking monkeys with super-inflated egos and matching vanity worshipping illusionary Gods and Saviors ".
Old 11-14-2007, 08:58 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #41 (permalink)
Stranger on the Internet
 
patkeefe's Avatar
 
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
Yes, I will post results when I get the engine back in the car.
__________________
Patrick E. Keefe
78 SC
Old 11-14-2007, 11:44 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #42 (permalink)
Registered
 
Join Date: Sep 2005
Location: Northern Virginia
Posts: 1,792
Great thread, Gunter. Thanks for posting this information.

I cleaned and re-lubed the distributor on my SC project cabriolet yesterday. My distributor was in a similar situation to Pat Keefe's -- on removal I found that I could barely turn the thing! It amazes me how far out of whack things can get and the engine would still run. Between the condition of the distributor and the monkeyed-with CIS (probably because the distributor was overlooked as a cause of starting/driveability issues), I may be more than halfway home to getting project cab back in fine fettle.

One different thing I did: Rather than pry the timer core with screwdrivers to remove it, I used (carefully) one of those cheap battery terminal pullers with a small block between the puller screw and the top of the distributor shaft. As Gunter said, be watchful of the tiny pin that locates/mounts the timer core in its correct position!

It was unbelievable how dirty/sticky everything was in there. After copious cleaning and lubing, it looks great and ready to go for another 100,000 miles. Also as Gunter said, use the dust cover. This distributor didn't have it and I'm thinking that was a major contributor to its horrible condition.

These distributors are expensive to replace -- take good care of the ones you have.

Brian
Old 11-19-2007, 04:44 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #43 (permalink)
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
when i unplug my vacume lines and plug to check the timing the idle jumps to 1500 so i cant check the timing without them connected. Anybody know what the problem could be? its an 82 sc right now its at 5 degrees with the lines connected. I havnt done the distributor service yet
__________________
82 SC , 72 914
Old 11-19-2007, 12:21 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #44 (permalink)
Somatic Negative Optimist
 
Gunter's Avatar
 
Join Date: Mar 2002
Location: Winlaw, BC, Canada
Posts: 7,206
Garage
Sounds like the lines are crossed.
Check the vac connections at the throttle body: Advance is connected in the REAR of the TB, the retard goes in front of the TB.
Timing is set with vacuum disconnected: 5 deg BTDC at ~900 RPM.
Along with that, you need to adjust the mixture and idle.
I suggest that you do the cleaning/oiling of the distributor and also make sure that the vacuum diaphragm works by sucking on the advance line and watching the movement inside. (Cap off)
Who knows where your timing is at the moment, something is screwy.
Service the distributor.
Then you'll know what shape the weights/springs are in and that the parts move freely.
__________________
1980 Carrerarized SC with SS 3.2, LSD & Extras. SOLD!
1995 seafoam-green 993 C2, LSD, Sport seats.
Abstract Darwin Ipso Facto: "Life is evolutionary random and has no meaning as evidenced by 7 Billion paranoid talking monkeys with super-inflated egos and matching vanity worshipping illusionary Gods and Saviors ".
Old 11-20-2007, 06:51 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #45 (permalink)
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
I appear to have two different sizes of springs on my advance weights is that normal? I cant get in there though because two of the three mpg allen screws are stripped out. Looks like i hit a dead end on my rehash. Im not too keen on ez outing them but it looks like thats the only option. Any bright ideas?
__________________
82 SC , 72 914
Old 11-23-2007, 01:52 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #46 (permalink)
 
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
also how much movement is the vacume advance arm suposed to have? It holds vacume fine but the arm doesnt move at all when you blow or suck on it is that bad?
__________________
82 SC , 72 914
Old 11-23-2007, 01:55 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #47 (permalink)
Registered
 
Join Date: Sep 2005
Location: Northern Virginia
Posts: 1,792
The vacuum advance plate was frozen on my distributor on my '83 cab before I rebuilt it. Penetrating oil and slowly turning it back and forth freed it up. FYI, the three screws on mine were the slotted type and not allens.

Brian
Old 11-23-2007, 03:32 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #48 (permalink)
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
how free is free? Seems like it should have to move about a half inch?
__________________
82 SC , 72 914
Old 11-23-2007, 03:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #49 (permalink)
Registered
 
Join Date: Sep 2005
Location: Northern Virginia
Posts: 1,792
That's about right. You'll see how it operates if you can get yours disassembled.

Brian
Old 11-23-2007, 04:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #50 (permalink)
Registered
 
Early_S_Man's Avatar
 
Join Date: Dec 1999
Location: TX USA
Posts: 9,804
Send a message via Yahoo to Early_S_Man
Porsche Crest

Yes, two different springs are used. The lighter spring provides the rapid ramp off-idle, and the heavy spring provides the gentle, slow ramp after 2500 rpm engine speed.
__________________
Warren Hall, Jr.

1973 911S Targa ... 'Annie'
1968 340S Barracuda ... 'Rolling Thunder'
Old 11-23-2007, 07:30 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #51 (permalink)
Somatic Negative Optimist
 
Gunter's Avatar
 
Join Date: Mar 2002
Location: Winlaw, BC, Canada
Posts: 7,206
Garage
Quote:
Originally Posted by porsche930dude View Post
how free is free? Seems like it should have to move about a half inch?
The vacuum advance limit is determined by the internal stop.
Make sure the vac advance plate pivots freely in the magnetic pulse generator, use penetrating oil.
Now that the pod is off, test the vac diaphragm by sucking on the line connected to the advance nipple.
It moves just a little but the important issue is that it holds the vacuum and doesn't leak.
As for the broken Allen screws, I suggest that you go to a machine shop to have them drilled out on a milling machine. If you attempt this yourself, the drill will wander off into the softer Alu material; not good.
Unless you have the right equipment and skill to do it, you'll ruin the distributor body and you'll be sorry.
I believe the thread is M4 but if all fails, it can be drilled/tapped to a sligthly larger SAE - NF size thread.
Leave it in the hands of a good machinist.

Early_S said it about the springs/weights.
__________________
1980 Carrerarized SC with SS 3.2, LSD & Extras. SOLD!
1995 seafoam-green 993 C2, LSD, Sport seats.
Abstract Darwin Ipso Facto: "Life is evolutionary random and has no meaning as evidenced by 7 Billion paranoid talking monkeys with super-inflated egos and matching vanity worshipping illusionary Gods and Saviors ".
Old 11-24-2007, 07:29 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #52 (permalink)
 
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
Thanks guys! Iv got it all back together i think the problem lies elsewhere. I feel bad asking all these questions in someonelses thread but here goes. As gunter said to check the vacume lines. They seem to be in the right places advance in the back and retard at the front lower and the wur goes to the upper larger port. But the suctive power is questionable. The reason the idle rises when the lines are disconnected is beacuse the retard has alot of suction at idle and the advance doesnt. Then when its reved the retard vacume drops and the advance sucks under load and when reved up which seems normal but.... is it? Should they suck equally at idle?
__________________
82 SC , 72 914
Old 11-25-2007, 06:58 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #53 (permalink)
Somatic Negative Optimist
 
Gunter's Avatar
 
Join Date: Mar 2002
Location: Winlaw, BC, Canada
Posts: 7,206
Garage
Quote:
Originally Posted by porsche930dude View Post
As gunter said to check the vacume lines. They seem to be in the right places advance in the back and retard at the front lower and the wur goes to the upper larger port. But the suctive power is questionable. The reason the idle rises when the lines are disconnected is beacuse the retard has alot of suction at idle and the advance doesnt. Then when its reved the retard vacume drops and the advance sucks under load and when reved up which seems normal but.... is it? Should they suck equally at idle?
You say: The reason the idle rises when the lines are disconnected is because the retard has a lot of suction at idle....................
How can you have suction if the lines are disconnected?
Be more specific and refer to the OEM vacuum connections.
Do you still have the Thermo-time valve in the loop?
Pictures would really help to show how your lines are connected.
Timing is set with vacuum DISCONNECTED at 5 deg BTDC @ ~900 RPM.
Are you doing that?
Set the timing first according to factory specs, then connect the vacuum.
Even with the lines connected at idle, there should be no change in RPM.
What max advance does your strobe light show at WOT?
__________________
1980 Carrerarized SC with SS 3.2, LSD & Extras. SOLD!
1995 seafoam-green 993 C2, LSD, Sport seats.
Abstract Darwin Ipso Facto: "Life is evolutionary random and has no meaning as evidenced by 7 Billion paranoid talking monkeys with super-inflated egos and matching vanity worshipping illusionary Gods and Saviors ".
Old 11-25-2007, 07:35 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #54 (permalink)
Registered
 
porsche930dude's Avatar
 
Join Date: Sep 2006
Location: NY
Posts: 7,536
Garage
I made a new thread here http://forums.pelicanparts.com/porsche-911-technical-forum/379208-82sc-vacume-timing-problem.html#post3607237
__________________
82 SC , 72 914
Old 11-25-2007, 04:49 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #55 (permalink)
Matt
 
mhoffman's Avatar
 
Join Date: Oct 2007
Location: San Diego
Posts: 121
Has anyone diagrammed all the washers? I had them laid out nicely and in order during disassembly, but did not pay attention to the magnetic effect of the pick-up and got them jumbled...the diagram does not clearly show how many and where...

Thanks-
Matt
__________________
79 SC Targa
87 m491 Targa
73 BMW 3.0 CS
73 BMW R75/5
88 BMW M6
Old 12-03-2007, 05:40 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #56 (permalink)
Stranger on the Internet
 
patkeefe's Avatar
 
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
Bump for help for Early_S_Man. I figured anyone who has posted in here will get an email response via subscription, and many do not know of Warrens plight...
__________________
Patrick E. Keefe
78 SC
Old 12-28-2007, 07:15 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #57 (permalink)
Registered
 
Join Date: Mar 2007
Location: Kingston Ontario
Posts: 97
Just did this particular project this weekend. The timer core was damn-near welded on and it took an overnight penetrating oil soak and the battery terminal puller (great tip BTW, couple of screwdrivers had NO effect on this puppy). Interior of distributor was all bunged up with some sort of reddish oily junk and the advance weights were reluctant to move. Cleaned and freed it all up and stuck it back together again using the thinnest smear of antiseize on the part of the shaft the timer core sits on since I may want to get it off again sometime in the future. That fiddly little pin is a pain to work with since the core magnetizes any steel anywhere near it. Finally used a pair of wooden tweezers and a brass drift to get it in place. A tip for people haveing trouble getting a philips driver to properly engage the 3 bolts that hold the coil in place: a #1 Robertson (green square tip) screwdriver does a great job on these little bolts.

My distro had no washers in it but has about 1.3mm axial play. Should I try to take this out?
__________________
'83 SC Coupe
Old 12-30-2007, 08:42 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #58 (permalink)
Somatic Negative Optimist
 
Gunter's Avatar
 
Join Date: Mar 2002
Location: Winlaw, BC, Canada
Posts: 7,206
Garage
I am not too concerned about axial play; the wear marks on the gear should be in the middle.
If you like, mark the gear and take it off with a little puller, then use fiber or brass/copper washers to reduce the play.
I am surprised about the 3 small bolts being Phillips or Roberts.
If they are Phillips, I don't see how a Roberts screwdriver would work and vice-versa.
Various SC distributors I took apart always had small Allen bolts for a 3mm key.
__________________
1980 Carrerarized SC with SS 3.2, LSD & Extras. SOLD!
1995 seafoam-green 993 C2, LSD, Sport seats.
Abstract Darwin Ipso Facto: "Life is evolutionary random and has no meaning as evidenced by 7 Billion paranoid talking monkeys with super-inflated egos and matching vanity worshipping illusionary Gods and Saviors ".

Last edited by Gunter; 12-30-2007 at 09:17 AM..
Old 12-30-2007, 09:14 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #59 (permalink)
Registered
 
Join Date: Mar 2007
Location: Kingston Ontario
Posts: 97
Quote:
Originally Posted by Gunter View Post
I am not too concerned about axial play; the wear marks on the gear should be in the middle.
If you like, mark the gear and take it off with a little puller, then use fiber or brass/copper washers to reduce the play.
I am surprised about the 3 small bolts being Phillips or Roberts.
If they are Phillips, I don't see how a Roberts screwdriver would work and vice-versa.
Various SC distributors I took apart always had small Allen bolts for a 3mm key.
I guess the bolts are just another example of the stuff that can happen in a 25 year old car Probably someone had some metric philips along the way. BTW I beleive a true Philips head (as opposed to something like a Reed & Prince head,also cruciform) has a center squarish bit (thus the ability of the Robertson to engage) and the arms of the cruciform radiate out from the points of the square. It also tends to be shallower than a comparable R&P and has a flattened bottom to the hole.

Thanks for the comment on the axial play. The wear pattern was in the middle so I guess its OK. Besides I just got back from a mid winter gotta-test-to-see-if-it-works run and it was too much fun to immobilize the car again

__________________
'83 SC Coupe

Last edited by DavErb; 12-30-2007 at 12:38 PM..
Old 12-30-2007, 10:12 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #60 (permalink)
Reply


 


All times are GMT -8. The time now is 12:16 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.