Volvo Penta 855932 Prestolite 7801A advance springs

bollerwagon

Petty Officer 3rd Class
Joined
Oct 15, 2020
Messages
94
I am looking for the advance springs for my old AQ271C distributor and struggle to find them. original Part numbers seem to be 856249 or 855912 but those are nowhere to be found.
Assuming I am not the only one with this problem, did anyone find a suitable replacement?
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
What happened to the springs? If they rusted away and you are still using points then there is a good chance that the rotor shaft is also rusted and abrasive which wears out the rubbing block on the points.
If your distributor is the electronic version then point wear is no problem.
I was a Volvo dealer for many years and never had to replace the springs but in your case you maybe you should consider replacing your distributor with a Mallory marine style. That way you can use the spark plug wires over.
 

bollerwagon

Petty Officer 3rd Class
Joined
Oct 15, 2020
Messages
94
the distributor is perfectly fine, just the springs are broken. I am not really willing to trash it just because of a 5$ part.
No offence, but as I know the volvo penta dealers over here - I´d wonder if you´ve ever seen a boat older than 3 years... ;-)
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
OMC also used Prestolite distributors along with Mallory. You might have some luck with the obsolete OMC parts dealers. Mercruiser also used the Prestolite distributor on some Ford engines until the late 70s.
I was a Volvo dealer from 72-03 Along with Mercruiser, OMC and Berkeley Jet also used Prestolite.
 

saskflyer

Cadet
Joined
Nov 13, 2021
Messages
16
OMC also used Prestolite distributors along with Mallory. You might have some luck with the obsolete OMC parts dealers. Mercruiser also used the Prestolite distributor on some Ford engines until the late 70s.
I was a Volvo dealer from 72-03 Along with Mercruiser, OMC and Berkeley Jet also used Prestolite.
I have a 93 volvo penta 740b big block with a prestolite distributor, Pertronix makes a 8cylinder ignitor; part # 1589. Will this work in my distributor
 

bollerwagon

Petty Officer 3rd Class
Joined
Oct 15, 2020
Messages
94
I have a 93 volvo penta 740b big block with a prestolite distributor, Pertronix makes a 8cylinder ignitor; part # 1589. Will this work in my distributor
these are not springs, or do I get that wrong?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,537
I have a 93 volvo penta 740b big block with a prestolite distributor, Pertronix makes a 8cylinder ignitor; part # 1589. Will this work in my distributor
Why are you hijacking a thread?

Your distributor is already electronic pickup. You do not need anything that pertronix has for your distributor

Back to the OP. @bollerwagon there are 2 different springs in the AQ271c dizzy. That is how they got a knee in the advance curve. Do you still need springs? Or a complete dizzy?
 

itsathepete

Petty Officer 1st Class
Joined
May 23, 2018
Messages
300
Not a Volvo but I had an OMC with a prestolite distributor that had missing/broken springs. I got a set of springs and weights from an auto parts store for a few bucks. I think they were Mr. Gasket brand. I was able to find a pair of springs in the kit that gave me the proper advance curve. Might work for you
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,653
Try marine engine.com, look up a similar OMC engine….
I have found a couple of spare Prestolite distributors for my old 4.3 V6 complete with the springs etc on eBay….
If you use aftermarket springs see if you can find a hot rod shop with a distributor machine (very old school) they may be able to check the advance against factory specs. Otherwise you can experiment with an advance timing light to see if those springs got you close. You want enough advance for good performance but not too much because that will cause engine damage.
 

bollerwagon

Petty Officer 3rd Class
Joined
Oct 15, 2020
Messages
94
I still need those springs, the rest of the distributor works fine. Do you happen to know a specific product number or something?
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,653
What you are going to have to do is search based on your engine/carb combination, so if its an AQ 271 I'm thinking it is a 5.7 with a 4bbl carb, correct?
I don't have part numbers you're going to have to look for parts for similar engines (OMC or Mercruiser) that used the same Prestolite distributor.
I did some looking around, these parts are very hard to find as you have found, it might be best to quit chasing ghosts and upgrade to an electronic distributor. I was able to find them for my old 4.3 4bbl a few years back, mine are still good though. The Prestolite had a lubrication wick in the distributor shaft and you could pull off the rotor once a year and put a few drops of oil on the wick, lubing the weights and springs. That's what made mine last this long!
If I really wanted to keep the points distributor, I'd get some aftermarket springs and an advance timing light and experiment, you might get lucky and be able to do it that way. Here's my Sears Craftsman timing light from the '80s no doubt. You have to run the engine at the specified RPM, set the dial to the total advance spec # and it should read zero on the timing tab.
 

Attachments

  • Setting dwell, idle and timing old school auto shop 101.JPG
    Setting dwell, idle and timing old school auto shop 101.JPG
    1.2 MB · Views: 2

itsathepete

Petty Officer 1st Class
Joined
May 23, 2018
Messages
300
I was able to get a pair of springs from this set that worked with prestolite distributor and matched the factory advance curve. It took a little trial and error and you need an advance timing light or timing tape on your balancer.

 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,653
There you go nice find.
I still have a pair of Blue Dot springs for my 1970 Ford 302 V8 from the '70s lol.
 
Top