Newbie to the forum. Just bought a 77 F150 with the 400 engine. This has a 2bbl carb, and I'm seeing some fuel leaking out of the accelerator pump diaphragm (at the center where the shaft enters). Is this fix simple? I'm seeing a Motormite part 90082 at Autozone that is supposedly for Motorcraft carbs.

Thanks for any help.

 

Welcom. Replacing the accelerator pump diaphram is simply a matter of removing the cover - 4 screws - and replacing the diaphram. Good luck with your new truck.

 

Welcome to the site. Yes it is a very simple fix. My advice to you though, is that if the carb is old enough that that is happening, it wouldn't be a bad idea to go ahead and rebuild the whole carb. There is an umbrella check valve underneath the accelerator pump that can deteriorate as well.

 

Welcome to FTE

D5AZ-9B559-A .. Accelerator Pump Diaphragm (Motorcraft CM-2092)

C4AZ-9576-A .. Accelerator Pump Check Valve (Motorcraft CM-825)
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Be careful when removing the cover, there's a coil spring behind it.

The check valve should also be replaced, it's behind the pump.

 

One thing I would definitely check while the pump cover is off is the flatness of the cover. I had a chronic problem with the accel pump leaking on my holley. Turned out the pot metal cover that the lever mounted to was warped. It never fully clamped the diaphram.

I fixed it by getting 1 of every grit of sandpaper the hardware store had. Starting with the lowest grit on a flat surface (I had a piece of polished marble, glass would also work) untill the part was flat. I then moved up to the next grit and polished until the scratches from the previous grit were gone. I continued with this up through all the grits. When I was done, the part looked awesome.

One tip for knowing when to move up a grit, polish in different directions for each grit. If one is polished left to right, on the next one move up and down. The scratches from the previous grit will be in a different direction from the current grit and it is easy to tell when the previous scratches are gone.





Or you could just buy a new pump cover....

 

Thanks for the tips guys - I see Motormite makes the pump diaphragm (part 90082), but not sure if anyone makes the check valve aftermarket? Believe me, I like Motorcraft parts, but Ford dealers don't discount their parts like the GM folks do. I can walk into at least 3-4 dealers here in eastern NC and get GM wholesale cost plus 5% on most any part. Never found a Ford dealer across the US that would do that.

 

Well, thats because GM marks their prices up 500%, then discounts from that to show what a great "deal" you are getting. There are Ford dealers out there with discounts (me being one). Check out my site. More than prices, I offer the best service as well.

~Kenny

 

OK, let me not argue incessantly, as I'm a newcomer here, but retail prices on similar parts for Ford and GM, are, on the average, the same. I'm talking more about mechanical parts than body parts here. Price an OEM caliper for a 15" wheel, for a similar age Chevy and Ford truck and see what you come up with. Price an alternator of similar amperage. Most of these prices are close. The discounts do matter - thanks for the offer to check your site out. I'm going there now...

 

You can waltz into any autoparts store in North America with those Motorcraft part numbers, as they can be crossed over to the brands the autoparts stores sell.

That's one reason why I listed them. The other reason is...they are also the correct part numbers for your application.

Did'ja know that there's more than one 2bbl accelerator pump diaphragm used in the 1970's? 1962 thru 1974 (and some 1975's) is one type, 1975 and later is another.

The check valve is the same 1962 thru 1979.

btw: Motorcraft is also carried by some parts stores.

 

Do not take this the wrong way I am merely pointing out something that confuses me ......... I checked out your website, figured you being a sponsor and all it was the least I could do, but the catalogue only goes back to 1980............kind of useless for us guys with older trucks
Not that I could order from you, stupid custom duties and taxes to get new stuff into Canada, increases the price to a non-competitive rate.

 

As a guy who orders a lot of stuff from the sates, I urge you to look at the different shipping options. Fed-ex never charges me anything for customs and brokerage fees, but UPS always does. USPS is hit or miss.
we should start a poll in the Canadian chapter.

 

I have used USPS several times for used parts for my 53 no probs, UPS sucks out loud no matter what new or old, never tried FedEx. Brokerage fees are ridiculous for UPS..... sometimes 40% of cost

 

I can give you any part number you want all the way back to 1948, verify that the part number(s) are still viable, check y2k's (or any other FTE Ford dealer sponsors site), and give you the prices.

If the parts are obsolete, I search several Ford obsolete sellers websites for them, and post the info.

btw: I don't work for any FTE sponsor, this is just a hobby.

 

Let me jump back in here. Just fixed the pump diaphragm with a $3.99 part from Motormite. Did the trick - no leakes whatsoever. Apologies for not using Motorcraft parts - this truck could be a huge money pit that I'm not willing to dive into (yet). By the way, the orange rubber flat piece just behind the pump diaphragm was not ripped or torn -seemed to be in good shape. I take it this is the check valve.

Thanks for all the tips - I still may buy my friend's Edelbrock 1407 (750 cfm carb). $100 for a nearly new carb is just too good to pass up, unless you folks think that just won't work on the 400 motor.

thanks

 

It doesn't matter to me what parts you use, I usually post the Motorcraft number(s) for cross reference info.

The check valve has a small tit on it at the center, that over time...breaks off.

Most ppl never replace it, and the accelerator pump problems all these Motorcraft 2 bbl carbs have, will continue if that tit is torn off.