VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 1930 Chevy Fuel Pump

Hello again friends,

I've been working towards getting my '30 Chevy 2 door coupe running, which it hasn't in probably 40 years. my latest hurdle is the fuel pump.

The fuel pump that was on it when I inherited the car from my dad was on it when it was running. It appears to be incorrect for my car:

[img]https://photos.google.com/album/AF1...ipPIShS-_c_tnC8hCSWL9FKb5BP_m8NMaemOfqnh[/img]

[img]https://photos.google.com/album/AF1...ipNhuxHz8rtL2-lY7MU6aYcqmWqdy8VGYUQXdBAy[/img]

When I removed it, I saw there is a major crack in the flange that holds it to the block:

https://photos.google.com/album/AF1...ipPDNWRFERN9Yzktctv6mTh2kCBTMf6aYM37Ux8I

In the trunk I found another fuel pump, also appearing to be incorrect for my car:

https://photos.google.com/album/AF1...ipNH7TGq7D11ypkCYHi6Yh0mPEjrutJQxjJZtAzd

I cleaned and rebuilt this pump, but I can't tell if it's going to work properly. When the 2 body sections are apart, you can see how much space there is between the rubber diaphragm and the spot it's suppoesd to seat on:

[img]https://photos.google.com/album/AF1...ipMLyS5elzhSGWSdHdBRKYkxyIJ_5tPD3mPbOgY0[/img]

When the pump is fully assembled you can move the lever quite a bit before it actually does anything:

[img]https://photos.google.com/album/AF1...ipMjqNTHhOnf-VUIijyxoYPx20UmgVL08de7ZSfD[/img]

[img]https://photos.google.com/album/AF1...ipMJw7hkoznca3FW9_T7SrfBoIXUfDIWJU0bHR0D[/img]

When the lever gets to that point, it doesn't seem like it can be pressed any more than that. So I doubt the diaphragm is moving at all.

How much of this is normal?

Thank you!

Unable to open your photos. If they are jpegs you can use the "full editor" to add them to your post.

Where might I find the “full editor”?

Clicking the links doesn’t open the link?

When you post a thread, the “Full Editor “ button is at the right hand side to the bottom of the reply box, next to ,,, Post reply, Preview reply, then, “Use Full Editor”

I found the “full editor” button, clicked it, and it opened a new window. I don’t see anything different, the choices are all the same. I thought perhaps I should copy the photo to the clipboard and paste it into my post, but “paste” wouldn’t work.

How do you embed an image into a post with “full editor”?

"Attachment Manager" close to the bottom next to the paper clip is the means to attach files or photos in a post. There are limits to the size so it may take some alteration for it to be accepted.

Here is a couple of pictures of the correct 405 AC pump for your car. The clean one has a flat brass nut covering the forward most valve by the fuel outlet. In 32 they changed to an air dome instead of the flat nut. Part number of the pump stayed the same and both will work. I attached a picture of a core with the air dome. So you are looking for an AC 405.

Dave

This is my EDITED original thread....

Hello again friends,


I've been working towards getting my '30 Chevy 2 door coupe running, which it hasn't in probably 40 years. My latest hurdle is the fuel pump.


The fuel pump that was on it when I inherited the car from my dad was on it when it was running. It appears to be incorrect for my car (Photos 1 and 2).


When I removed it, I saw there is a major crack in the flange that holds it to the block (Photo 3).


In the trunk I found another fuel pump, also appearing to be incorrect for my car (Photo 4).


I cleaned and rebuilt this pump, but I can't tell if it's going to work properly (Photos 5 and 6).


When the 2 body sections are apart, you can see how much space there is between the rubber diaphragm and the spot it's supposed to seat on (Photo 7).


When the pump is fully assembled you can move the lever quite a bit before it actually engages the pull rod/diaphragm (Photos 8 and 9).


When the lever gets to that point, it doesn't seem like it can be pressed any more than that. So I doubt the diaphragm is moving at all.


How much of this is normal?


Thank you!

i would personally get the correct AC 405 fuel pump, they are readily available and easy to rebuild as long as they are not cap is not warped or distorted from overtightening screws.. biggest issue with no suction is typically the glass fuel bowl is not seated !!

when you rebuild them the instruction typically tell you to install the diaphragm place cover on and loosely install screws, work actuator to center and set the diaphragm. you should be able to put your finger over the inlet and when you pump the lever you should feel a good suction. If not then the glass bowl may not be seated and sealed (most common issue) or the diaphragm is not centered & set. other issue is warped/ distorted housing from overtightening screws !!

i have rebuild a few of these, and after rebuild i do a bench test with my vac/press gauge. typically get 6-8Hg on suction and 1-2 PSI on discharge. this is on the bench with full stroke, when installed in the car it is a little less as the arm does not travel 100% :) on the car no plugs installed i typically get around 5 Hg on hte suction side

one of hte trial and errors of a worn fuel pump lever arm :!:! https://vccachat.org/ubbthreads.php/topics/430749/2.html

The pump in photos 1,2,3 is an aftermarket replacement of the original. The others have a different angle to the engine block than the 90 deg. of the original. The lever and angled mounting bolt holes appear to be correct so it might work with alteration of the routing of the line from the gas tank.

Thanks BearsFan315, that is a huge help! I lost the rebuild instructions when I bought the kit from The Filling Station, so I was using what I could find on the internet. I'll give that a try, and check with a vacuum gauge. BTW, are you in Illinois somewhere? I'm in Grayslake. It would be fantastic if we were close, I don't know ANYONE around here that has a Chevy like mine. Everyone and their mother has a Model A.

Chipper, thanks for the advice, I think I may get this to work!

no, i am out in Virginia on the Coast

I have a copy of hte instructions in my paperwork. Yeah i keep everything for the 1929 & 30 :)

Why couldn't he clock the last pump in his pictures to match the 405?

Dave

If I remember correctly the six screws that hold the pump together will only allow clocking 60 degrees and the offset is in the 30 degree range.

So reading this:

"install the diaphragm place cover on and loosely install screws, work actuator to center and set the diaphragm."

means press the lever half way, then tighten it up?

i press actuator in until the diaphragm sits flat and level, then tighten it down GENTLY


this is from the instructions i have: ( i can scan it and send it to you if needed)

If you could send to me, that would be very helpful!

I'll PM my email address.

Sent