Fuel Pump Frustration
 

The stock fuel pump in my 68 bird 400 finally failed after 20+ years earlier this Spring. In shopping for a new one, the main brands available were AC Delco, Airtex, Delphi, and Carter. I chose the Delphi as the reviews seemed a little better. When it arrived, I had some reservations as it was made in China and they didn't even include a gasket. Put it on and ran great until last week when it died and left me stranded. Didn't even last 200 miles. So, this time I ordered the Carter since it was supposedly made in USA. Just received it looks exactly like the same tooling as the Delphi and also says Made in China. I think Airtex is probably the same and I don't see the AC Delco one out there anymore. I am thinking of just sending the Carter back because I can't enjoy my car wondering if/when the pump is going to leave me stranded every time I drive it.

I have this (pics) aftermarket pump I am thinking of seeing if I can find a rebuild kit for but not sure exactly what it is. Can anyone identify this?

Also thinking of just going Robb Mc. In either of these cases, I think I would need to make a custom pump to carb line.

Any suggestions? Is there a stock replacement out there that isn't a pile of junk? Car is stock so hoping to keep it as close as possible. Thanks.

I have a Holley pump. So far so good but it requires a regulator

Looks like one I had which was a Holley, and we are talking 3 decades ago!

PS
Holley still offers this pump and it’s item 12-389-11 and goes for 200 bucks and is stated to not need a regulator.

I would guess that they offer a rebuilding kit if needed.

get the robmc and be DONE! make the line.

Thanks. This pump is at least 20 years old. I was trying to ID it by the numbers on the metal tag but no luck yet.

Yeah thinking that, but, was trying to see if it is worthwhile messing with this aftermarket one I have first.

When I had my motor built, I put the BOP Carter style "high volume" pump on it. I replaced it with a RobbMc pump because it couldn't keep up with the new motor. But, for a stock type motor I think it would be fine. Only 50 bucks.

This is what I just did for my buddy’s car he went robb mc but wanted the stock line going to carb. Used a AN fitting with npt 1/2 on other side then a qjet fuel fitting cut and weld and it’s ready to go.

Holley 12-837.
https://www.summitracing.com/parts/hly-12-837

Yes, that's it. Thanks.

Hey Pat,

I looked up your pump number in my GM parts book and came up with GM 6417212, AC 40607. I looked on eBay but nothing at this time with an AC NOS unit. There was an NOS unit in early June that sold for $230. When I placed that number for a search on eBay, many of the replacement pumps popped up from some of the manufacturers you spoke about. So much of this stuff is made overseas today, it's hard to trust the durability of anything! Good luck!

Pat,

I checked the for-sale parts group for Firebirds here on PY and last year this member had a number of NOS parts and one listed is your fuel pump. Very expensive of course but you if this 1oldgoat still had that pump, you would get a USA made quality unit...

Good luck!


1oldgoat
Chief Ponti-yacker


68 GTO/Firebird 400 fuel pump AC #40607 6417212 $275

I have this Carter 120 gph pump new in a box and its Made in the USA.

https://www.summitracing.com/parts/CRT-M6907

And only 120 $ vs 200ish for the Holley and Edelbrock.

Even though it might save you some bucks to go with a NOS pump there’s two problems with that.

1) the diaphragm has likely already started to dry rot since they never bagged them up.

2) the diaphragms are likely not made for todays Alky cut fuel.

Both of these combined and you have a new pump that will only last you months like you have experienced.

"Todays" alky cut fuel (gasohol) has been around since at least 50 years.
And motorists in the northern states have always poured alcohol into the tank to avoid ice forming in the fuel system during winter.
I would not worry using an original NOS ACDelco fuel pump.

Chinesium pumps are another story.

JMHO

I carry nos pump in my trunk. Saved my butt once. I think as steve said age and fuel. I have another nos 2nd gen and a nos A body new. I think I have a new old stock 421 SD airtech pump stored in garage with the screws on the bottom.i had 2 used one.Bought Robbmc just need to adapt it.

Thanks for the lead, Jack. I agree with the later post that I would have concerns running an old pump where the diaphragm could already be hardening from age.

Thanks, looks like a good option.

Nice work. So, these types of adapters are not readily available then?

In terms of Alcohol used for gas line antifreeze, 12 Oz added to 20 gallons is a very different ratio then 10% of every gallon out of the gas pumps today in terms of fuel pump diagram life.

Also it’s been only 40 years that all major pump gas makers have been adding grain alcohol to gas a tithe board.

this pump feeds my 505 just fine for street use.

I made a pretty lengthy post about this a long while back with pics showing all those pumps sitting together outside their boxes and there was no discernable difference between any of them, which led me to believe they were all the same reboxed garbage. Even the AC Delco I had was the same and no longer carried the AC Delco logo cast into the aluminum housing, so I didn't accept it as a "real" AC Delco.

I've later posted how the most recent renditions of these pumps are hit and miss on reliability. The last round of these I went through on one vehicle, the first one didn't get me a mile from my driveway and died. Napa swapped that one for another, and that one got me about 10 miles from the house and I had to retrieve my trailer and tow it back. Napa at that point just said "here's your money back" LOL They didn't have another in stock for a warranty swap.

In a nut shell your best bet these days are really only 2 options that I consider.
One, go with a RobbMC pump and get yourself one of his extra rebuild kits to have on hand for $25 just for good measure, and just get used to the fact you have to custom bend and flare a new fuel pump line.
Two, more money and more work, go electric in the tank as all the modern cars do these days. Usually my go to option for any engine making 450-500hp or more, and then go the extra mile to make things appear stock. Not a cheap option, usually $1000 when done.

I don't even consider store bought $30 pumps anymore.

I agree today's off the shelf pumps are a joke for the most part, and trusting a decades old NOS or NORS pump can be risky too but as far as one of the more expensive pumps from Summit, Jegs, etc, they appear to not have a provision for a return line. A return is a must for helping control vapor lock. Unless I am missing something, what can be done about that?

I would take that chance because of all the crap that is being manufactured overseas with very little service life being reported with these parts! But that is a personal choice!!! If that was a problem with NOS pumps, I don't think they would be snapped up quickly when posted for sale or command the high prices we're seeing!!

I was messing with that old holley I have and noticed that it does actually have one of those fittings for a flaired line. So, I guess this answers that question.

Personal choice Pat, but with all the problems reported on these offshore made parts, I would take the chance. I don't think that would be a problem with an NOS part and if it was my car, that is what I would do. BUT the price is really high, like so many NOS parts you find today. It appears people are willing to pay a lot for these pumps because few show up and when they do, are snapped up right away. Your 68 400 Bird, like your TA are so beautiful, I would stick with originality but that is a personal preference on my part. I remember you finding and rebuilding a correct date coded voltage regulator for that car but that is a different issue, and it didn't cost that much! Good luck and let us know!!

At this point far as I know all the over the counter pumps are going to be reboxed Airtex pumps, either Mexico or China origin. The horror stories I here over and over and over again tell me not to touch any of that with a 200' pole.

Some folks are so persistant, and cheap they tell me of trying them 3 or 4 times before throwing in the towel and going another direction. They also call in here blaming ALL their flooding, running poorly, difficult restarts after sitting a few days and even sucking the bowl dry issues on the carb, when it's the Airtex fuel pump instead.........FWIW......

Then comes the problem of finding a good in tank pump. Last one I bought was an A/C Delco replacement from GM that lasted all of maybe 10 uses spread out over a year and seven days, just past the one year warranty period.

It is just unreal that in the late 60s we had the technology to mass produce these pumps with high reliability and reasonably long life. Now we can't. We can debate the ethanol issue but we also have superior materials, neoprene, etc that are resistant to the crap gas. Also the new pump failures are in a short time so can't be the gas.

I need a 3 line pump so at this point am either going Robb Mc or seeing if I can get this old holley working. I am not seeing any other 3 liners out there. Not going to drop big money for old nos for a chance it might be good. Reliability and piece of mind is the most important.

Is the Robb Mc website the only place to get their pumps?

Are there other 3 line aftermarket pumps I am missing?

The intank set up most people use are from tanks inc or other retro fit modules from brands like holley, aeromotive etc, most use top quality pumps like walbro that are very reliable and can support very high HP.

Delco did mass produce these pumps for many years, and I think you could still get a GM part back in the 90's. But, like so many manufacturers today, they went overseas because it was cheaper to produce aftermarket parts. As a result, we see a lot of crap today. Cliff R is right, much of this stuff is made with inferior materials with poor tolerances that are not followed like they once were when made in this country. We see this a lot in the PerTronix ignition parts that have an unbelievable failure rate. That subject has been discussed here in detail and Cliff has many horror stories about these units too. Sad but true today in aftermarket products which at one time were as good if not better than factory parts!!

I'm not sure how much flow you need but I don't buy into every aftermarket pump being total junk. The fail rate may be high but it's not 100%.

I recently bought a Delphi pump. So far it works, doesn't overpower the carb inlet, and hasn't broken yet. I don't know if or how long it will hold up but so far so good. I know it's not my good luck saving me.

As to why fuel pump quality may be poor, it's not a lack of technology. While every brand may source from the same manufacturer and use the same design and materials, I want to believe some are better at managing quality than others.

I don't blame Chinese manufacturers. They just make stuff for other companies. They deliver what their customer contracts for. To me, a brand can decide how they want to trade off quality against price and manage a Chinese or any other manufacturer to achieve their goals. Unfortunately, it seems the market has driven every brand to the same cost-driven business model that accepts high field failure and/or return rates.

If I had a 500 hp engine and wanted high quality, good support, and reliability, I'd probably pay $225 and custom-fit the lines. But I don't. So I take my chances on a $40 bolt-in.

When I was shopping, I found Spectra sold off their fuel pump line in the past few years and it seems others have done the same. So I looked for a brand that at least put their name on the pump. Delphi did, so I bought it. Is it better than any other? I don't know, but Delphi knows I'll be reminded which brand failed when I replace it. To me, the name on the part is worth more than no name, even if it comes from the same factory.

I don't remember what pump I put on back in 2000 but it lasted 23 years. It wasn't AC Delco since it didn't have the AC on it. It finally went in May and I replaced it with the Delphi. That left me stranded last week. Didn't even last 200 miles. I ordered a Carter last week since I thought it was made in USA and the picture looked like my pump from 2000 (had the 2 weep holes). I just got the pump and it was not the pictured one, instead it is identical to the Delphi. Only difference is the Carter ink stamp instead of the Delphi ink stamp. I don't even want to try it.

Fwiw, my 71 TA has an air tex pump on it and it is still working fine after 13 years. Quality seems to have fallen off for all of these in recent years.

Yikes, that sounds frustrating...

That experience does make a case for a RobbMc or electric pump..

The market for these mechanical pumps must have evaporated to the point where nobody cares enough to even track the quality.

In a previous life, I worked for a company that made stuff and sold the same product 2 ways: 1) to OEM manufacturers and 2) through retail chains.

The "allowable" return rates (ie out of box failures) were almost two orders of magnitude different. An OEM customer would not buy if we shipped them a bunch of failures. A retailer didn't care much how many came back as long as we paid for them. So new products with immature quality went to retail channels before they went to OEMs. Just business.

"The market for these mechanical pumps must have evaporated to the point where nobody cares enough to even track the quality."


I stepped up to a Tanks,inc style EFI pump and tank about 8 years ago.
8 years and not one issue. I bought the 225 liter/hr street pump.

I am Not cutting holes in my 64 GTO trunk floor (so I passed on the access plate and easy pump removal from the top (in the trunk).
(I RUN TWO 225 LITER PUMPS IN ONE OF THE TANKS, INC TANKS WITH A CUSTOM TOP COVER THAT MOUNTS THE DUAL PUMPS.

Second pump is a back-up pump.

My biggest gripe with the "factory (Chinese) timing cover pumps was the fuel pressure was all over the place.
Tried 3 M-Pumps and all were POS parts.

Tom V.

I just went through this with a Carter 6907 when I swapped from a Holley to a Qjet. I ordered a factory repro line thinking I would massage the carb inlet end to make up for my additional intake height only to find that the outlet on my pump is. clocked different than the OEM pump. The radius at the elbow on the repro hard line (In-line Tube)was ahead of and tight to my crank pulley so no bueno. Prying it further just jacked up the alignment at the top. I had bend and flare one out of nicop using the OEM as a template with a tighter bend at the fuel pump.

That's never really been a problem that I've seen as long as you go with a genuine Walbro and I've been dealing with them for 25 years. That's about as good as it gets, and what the OEM's have been using for years. There are a lot of counterfeit Walbro pumps on the market for cheap, avoid those.

Always a chance something doesn't work but in the grand scheme of things good Walbro electric pumps failing prematurely on a regular basis is certainly not the norm. Millions of them on the roads today.

One other option I found is that there is someone in CA that restores these original crimp style mechanical pumps. I think it runs $275 with shipping. I would do this before spending that on an old NOS pump. Also, I would only do that if I had an original AC Delco pump to start with and bone stock originality was necessary for the car. Anyone familiar with this person or that rebuild service?

Not the same on the npt side that’s probably 1/4 or 3/8 at best McRobb is 1/2 npt. I could be wrong but that’s going to be a little harder to find.

Doing some more research I see the Robb Mc pump delivers a constant 7 psi where the factory pumps were in the 5-6 psi range. Are there any issues with the additional psi on a stock 68 400 build with stock Q-jet?

I chased a flooding issue and actually measured the "holding power" of the inlet valve on my QJ (69 Buick 7029240) as taught by Cliff. I measured 12 psi to overpower it... quite a bit higher than 7.

My copy of the 1970 Service Manual has this interesting note:

http://forums.maxperformanceinc.com/...1&d=1692072223

So at least for 1970, 7 psi was "within spec" for a mechanical pump with a return line/vent.

I don't know if the float, needle, and seat were "weaker" in 1968 but I doubt it.

Several members in other posts have warned variations in pressure will raise or lower the fuel level in the bowl, but I don't know how sensitive carb tuning could be to that variation. Those with knowledge can address that risk.

Mike

Typically a good needle and seat assembly shouldn't have any issues holding 7 psi or more. For what it's worth I've had those stock mechanical pumps show as much as 9 psi even though they are rated at 5-6 so they aren't very consistent anyway. I've also had them show as little as 3 psi. :noidea: Just another reason why I avoid the darn things these days.

So I picked up a carter m4690 on a whim after reading this thread . Fits 68 gto and compared it against my M6122 deep can . The 4690 as said looks generic , has a light M4690 etching on the body , box says China . 6122 was bought maybe 10 years ago , stamped made in USA right on the body .and Pierce on the other side . Box also has federal mogal logo on it and 4690 does not . I’ll probably try to use the deep can 6122 when the time comes .

That Carter M4690 is the same one I just recently bought from Rock Auto, and what sparked this thread. It is identical to the Delphi I bought in May that crapped out. As mentioned above, I think they are all Airtex chinesium now. I plan on sending mine back.

When I built my 400 in 2012 , I picked up a USA made Delco unit locally - now why the heck didn’t I get 2 or 3 ?! My resto stalled out for awhile do to life , so I just fired the engine up this summer and the Delco seems spot on .

Looks like I'm going with a Robb Mc. Called them and they said there is a backlog and will be at least 4 weeks to get one out. I would like to be able to at least move the car before then and have a few options with questions.

1) I see that Spectra out of Canada has a pump available, MP1151SP. Does anyone know if they make their own stuff or if this is just another reboxed China pump?

2) Found a Korea made Carter on Ebay? It looks like the one that survived on my car for 23 years. Anyone know if these are actually better than the airtex Chinese ones?

3) I think I could rig up that Holley I have. I took it apart and the diaphragm looks good. The seal for the bottom cap looks a little suspect though, see pics. Anyone know what material that is, or I could use to make a new one?

Like I mentioned before, I honestly don't believe, and could not see with the naked eye, any difference between brands of stock replacement pumps (airtex, carter, AC etc...) and documented that in an old thread.

If you just want to roll the dice, I think any one of them would be fine for just moving your car around until the RobbMC shows up. That's really all those chain store pumps are good for in my opinion. In fact I used one just for that purpose to keep the Nomad mobile. That particular pump that came in a "carter" box would only show 3 psi fuel pressure cold and when it got warmed up it showed ZERO, even though the engine still ran, it idled which was good enough to move the car around when needed. I wouldn't dare drive it any distance though.

I did later swap that pump out for a Summit brand high flow pump (80 or 120 gph, can't remember now) and it immediately showed 8 psi on the gauge and stays there even after the engine is warmed up. I can at least drive the car around the block now without worry I'll be walking home.

See previous post re: Spectra

http://forums.maxperformanceinc.com/...9&postcount=32

Thanks for the refresh on Spectra.

Anyone ever hear of Pierce pumps? Found one and says made in USA on it. It even has the 40607 number stamped on it. Looks new not rebuilt as the Pierce logo is cast into the upper housing.

Never heard of it. Probably another product where a company does a simple process to it after it's shipped from over seas so they can put made in USA on it. LOL

Only way to know for sure is investigate the brand/company, the state their in regarding their laws, and see what they actually do, if you really want to spend a bunch of your time.