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1942 series 70 - fuel pump interchangeability

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Some of the previous owners has removed the mechanical fuel pump and put a delete plate on.

My car is 1942 series 70 Roadmaster, 320cid engine. 

Very difficult to find the pump here n Scandinavia... ...thus I ask you fellows to help finding "alternative donors" for it...

Which models & years fuel pumps are interchangeable with my engine?


Pekka aka tinsled

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OK, not sure where this will go, but as I look at the books....

The Hollander 1952 says Buick 1940-51 60, 70, 80, 90 all have the same fitting, #1537338. So any of one of these cars should fit. I imagine you need a double pump as you show above. The same pump will fit many other makes with the appropriate rocker arm. If you have a rocker arm you could swap into them, any of the following will fit:





















and that is the highest number in the Hollander I have. These are all for different makes and models of car.


MoToR's manual shows it as a series AJ with max. fuel pressure 4 p.s.i.. I have a 1950 manual and it corroborates The Hollander. The series AJ looks like this:

SeriesAJ.jpg.bb5ec2b384bbeceaef4ed9295469d42f.jpg Based on this picture, the pump you show is different and may not work properly. Further research would be needed.

The AC fuel pumps book also shows the series AJ as being used on 1938-39 series 40 Buicks plus 1940 series 40, 50 Buicks. I can tell you the AC part number but not the difference - I expect it is at least a different arm and may also be different fuel pressures. These pumps are AC type 529, yours should be a type 530 (this determines the repair kit = diaphragm, springs, valves, arm etc.).


Here is a snip from another AC pump book. The * means it is a combination vacuum and fuel pump. Again, I would do further research before buying a type 9762 pump. Keep your powder dry and hold on until something closer to the type you want shows up.  It will, eventually.







Edited by Spinneyhill (see edit history)
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This one is an AJ, but type 519, which is the same as type 529. I MAY work. I don't know the difference(s). MoToR's shows the diaphragms as the same for all Buick series AJ pumps 1940-50 and the fuel pressure is always 4 p.s.i.



Edited by Spinneyhill (see edit history)
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Thank you Spineyhill for the valuable information.


Looks like the rocker arm of #9762 is longer than of #529 & 530, also the "foot" is at different angle.

Could it be the camshaft is different for 1952 series 70 compared to previous models?


Unfortunately I do not have ANYTHING but the delete plate left of what has been with my car, no rocker arm, no core, not even smell... ;)


I'll keep hunting for #529 or #530


Is there any source for the diaphragm material - rubber canvas?  - I most probably need to rebuild the pump anyway if I will find a "NOS" or core... 

Edited by tinsled (see edit history)
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Then & Now supply rebuild kits that include diaphragms. Others do too. I suppose Bob's Automobilia will do kits for Buicks, which are just the same as others with small changes. They are all for AC pumps.





I see Bob's also has a rebuilt pump for sale.


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They all work from 1940-1951 like the book says.  CARS, Inc rebuilt mine.  I do have a spare, but I'm afraid to part with it.  All those years, it should be easy to find.  There is probably some minor differences between the number spinny quoted.  But, none of them are any good with ethanol unless you have it rebuilt.  A used one is as good as a NOS one.  I think there is one hanging on the engine of an old Roadmaster I bought the front bumper off of at Windy Hill Auto Parts in MN.  As for Willy....great guy to work with.5a89f7724b2f6_41Buick71WindyHilljunkyardforfrontbumper.jpg.63b40c0d00974b82fdb29686e553066c.jpg

Edited by Dynaflash8 (see edit history)
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