Difference in fuel pumps?

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I keep hearing that; but I've been using strictly 87E10 in my S since 99 with zero issues.So perhaps our Northern gasohol is different from American gasohol. Or I'm just lucky, I guess. Maybe I should change my "handle" to Lucky AJ.
Well strictly isn't quite correct. One time I went to the Racetrack, and ran a few gallons of premium 89; maybe 5 at most.
 
UPDATE:

As stated before, removed timing cover and eccentric is was present, reinstalled timing cover, installed new pump. Still not working, removed inlet line from mechanical pump and replaced with electric pump and car runs fine. I am currently on my second new mechanical pump, and still does not pump. So here is the break down, inlet line is clear, eccentric is in place, 2 new mechanical pumps, and it still does not run. I am beyond frustrated with this issue.
 
When you installed the 2nd pump, did you perchance position the eccentric at around 7 o'clock and see if you got pressure on the pump arm from the eccentric when you tried to line up the pump bolts?

I can understand your frustration.... this should be a no-brainer. Where are the pumps coming from?
 
Bought1 from AutoZone, the second from Napa. No pressure when car is running, put in the vise and manipulate arm and get pressure. Almost out of options, may have to use electric pump.
 
Ok so still no vacuum test then?
The vacuum test will tell you if the arm is being stroked by the eccentric. Just cuz the eccentric is there, rotates, and looks like it has the proper up/down action, doesn't automatically mean it's compatible with your pump.
Say you bench test the pump and it pulls the spec'd 10 inches. But once it's installed, it only pulls 2 inches vacuum. Maybe 2 inches is not enough to lift the fuel out of the tank, up over the top, down the pipe and up to the check-valve. That would indicate that the eccentric is not stroking it the same as when you stroked it manually. Maybe the pump is bad. Maybe it has the wrong arm on it. Maybe the eccentric is not stroking far enough. Maybe the install was iffy. Maybe for whatever reason the pump cannot pull it up. Maybe the E-pump can. That's what the Vacuum test is designed to discover.
I mean two pumps in a row? No vacuum equals no pumping.
 
Just ran a vacuum test on 2 separate pumps no vacuum pull at all. Eccentric must not be engaging the pump arm. Does anyone have the specs on the eccentric? are there different models?
 
Dartish said:
You have to buy 4 or 5 mech pumps before you find one that works. Then if it lasts over a year, you got lucky. Even the Carter replacement pumps are garbage now. On my 3rd one this year, one of them was junk right out of the box. In the process of saying screw it and buying a "good" electric pump, if there is such a thing and a decent regulator. Just my preference
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Yep, that was my experience earlier this year, I wasted so much time chasing my tail thinking I had other problems!
I wish I could bill autozone for the hours lost testing their two bad pumps for them!
One of the problems with being an "old timer" is that we remember when new out-of-the-box stuff could be trusted!
Now it has to be tested before bolting it on. That sux!
 
DARTLARRY said:
Just ran a vacuum test on 2 separate pumps no vacuum pull at all. Eccentric must not be engaging the pump arm. Does anyone have the specs on the eccentric? are there different models?
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Please take the pump(s) back wherever you bought them, tell them they're defective, and get your money back.
Remember, "the customer is always right" the parts store won't question your diagnosis.
The specs on the eccentrics are all the same, HD models are just made from beefier materials and coatings.
Don't waste any more time on this! Some of us have been right where you are now.
 
When I bench test the pumps they seem fine, it is when they are installed into the car that they do not work.
 
sccachallenger said:
I don't even know if this is possible to do, you are putting the pump arm UNDER the eccentric aren't you?
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It's been suggested that the OP turn the eccentric to 7 o'clock and see if there is pressure on the arm when trying get the bolts to line up. If no pressure is on the arm when installing like this, then it is not engaged. We don't know this answer.

OP: Did the eccentric look deep, like this one?
Mopar Performance Moly-Coated Fuel Pump Eccentric

The arm should stick straight back out of the pump about 4.5". Attached is a pix of a known working SBM pump for reference.
DSCN2240[1].JPG


You ought to be able to look right into the timing cover and see if the eccentic stick out well past the centerline of the space between the 2 mounting holes.

I'd buy a Carter direct from Mancini next time. At least there is a step of knowledge in the parts at work. I give NAPA a higher rating than AZ for selling the right parts.
 
I have the same eccentric pictured, and the same pump pictured. I pulled the timing cover to make sure it was in place. for some reason eccentric is not engaging.
 
I'm on my second one of those Carter muscle car pumps in a few months. The one I just got had an arm that rattles like you wouldn't believe and Wont even pump enough fuel to fill the bowls. Ran to AutoZone and got one of their super high quality $14 pumps. It works but certainly not for long
 
Crap, If I could ship a used pump that still slightly stunk like gas I would send you one.
The local USPS lady know me by name, and will not ship anything that has a slight car smell.
 
The pumps I have been trying to use are small block pumps, but the arm is not straight, it dips in the center.


pump.JPG
 
The bend may or may not make any difference. Any way you can take a pix of yours in the same orientation as the pix I posted? That is just to see if maybe the back part of the arm is too low, compared to the one I showed. A real pix of your pump straight on from the side would help to see if that is the case or not. Is the arm 4.5" long from the mounting flange, with the arm's angle at the eccentric being 3.25" from the flange?

See if there is a PN on the box. The Carter site shows an M60514 pump for a mid 70's small block and M60519 for mid 80's. (Just a different inlet nipple orientation.) I see AZ has a Delphi brand part listed that looks like your photo. PN AMF0048. I think I'd try the M6866 that sireland67 refers to above.
 
BTW, can you measure your pump mounting holes' location relative to the center of the crankshaft. (I.e., how far they are above the crank centerline?) I can check an earlier timing cover for that same dimension.
 
I have 3 different timing covers that range from early 70s to mid 80s, the holes all ,seem to be in the same place. My next step was to change covers and see if this may be the problem.
 
UPDATE:

I changed timing chain cover to an earlier model, installed the fuel pump, turned the engine over for about 30 seconds and pump was working fine.
Car runs fine now, don't know if there is a difference in timing covers, but switching covers solved my problem. thanks for all answers and advice,
 
sireland67 said:
Crap, If I could ship a used pump that still slightly stunk like gas I would send you one.
The local USPS lady know me by name, and will not ship anything that has a slight car smell.
Click to expand...

LOL! She is wise to your sneaky Mopar ways. Bet she drives a Prius.
 
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