Fuel pump leak?

mgbeda

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Hi Gang! I got Marty ('87 5th, stock) running really well now (I tried absolutely everything; finally drilling out, cleaning and adjusting mixture screws did the trick). But he's also developed a strong smell of gas while running. It does NOT seem to be coming from the carb. I can't see any actual leaks, but, there seems to be some wetish, brown tarry blobs on the top of the fuel pump itself. I can't see anything that could be dripping on it. Has anyone ever seen a fuel pump develop a leak like this? I will enclose some pictures from my phone.

Thanks,

-mB
 

mgbeda

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Hi Gang! I got Marty ('87 5th, stock) running really well now (I tried absolutely everything; finally drilling out, cleaning and adjusting mixture screws did the trick). But he's also developed a strong smell of gas while running. It does NOT seem to be coming from the carb. I can't see any actual leaks, but, there seems to be some wetish, brown tarry blobs on the top of the fuel pump itself. I can't see anything that could be dripping on it. Has anyone ever seen a fuel pump develop a leak like this? I will enclose some pictures from my phone.

Thanks,

-mB

20220211_132422~2.jpg
 

volare 1977

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Most likely gas coming out the weep hole indicates the diaphragm in the pump is going bad
 

Aspen500

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Check your oil for gas also. It's rare but, I ran into a couple pumps that leaked gas into the crankcase. Like Volare said, fuel coming from the pump vent hole equals diaphragm starting to leak. If it leaks worse, it'll pump gas out the vent and if it gets in the alternator or plug boot, it can ruin you day real quick :eek:
 

mgbeda

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Okay then. Thanks a lot for the voices of experience. At least it's not something I broke while working on the carb.

Is it easier to get these pumps out from top (remove the alternator first) or from under?

-mB
 

Justwondering

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I was replacing my water pump a few years ago, so I did the fuel pump at the same time as well as the fuel filter. So I had everything out of the way.

How Do You Replace a Faulty Mechanical Fuel Pump in Your Car?

Thats a writeup for generically replacing a mechanical fuel pump.

I did mine from the top, but I moved the alternator out of the way and since I was replacing the fuel filter, I could move some of the fuel lines out of the way.

BudW will tell you to use a wrench on the fuel pump fitting AND on the line nut.. do it that way. If you wrench on the pump but do not use a wrench on the line one or the other is going to go sideways and cause trouble (crimp, collapse, something). Then you take the part back down to the counter sales person and confess you need another one. They all chuckle and sell you another one and you just wasted another 47 minutes of your life and more cash.

Not too hard to do but remember to take off the battery lead so you don't cause other problems and I used gasket sealer like they recommend. Hand start the bolts so you don't cross thread them. Put a piece of cardboard under the work area of the engine bay so when you drop the bolt (not once but twice) you can find it easier and get it easier by just pulling the cardboard towards you instead of crawling on the floor trying to reach it under the car.

And pull your hair back in a ponytail or the ends hang down in your way.

JW
 

mgbeda

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All righty. Thanks a lot everybody. I've got the part on order, should be able to get it tomorrow. Wouldn't want to have a weekend without a project.

-mB
 

Aspen500

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Like JW said, if you take the alternator off, it's not too bad to change the pump. Makes it easier also if the engine is turned so the fuel pump eccentric isn't pressing on the pump arm.
 

Mikes5thAve

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From top with alternator removed. At least it's not an 88/89 with the bigger bracket, that thing gets in the way.
If the smell isn't from that the gas lines can rust where they run along the frame rail from road crud holding water on them in there like a sponge.
 
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