Thread: Fuel Spurting Out

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Hi,

I'm new here to this forum. I've got a 68 chevy C10 with a 350 small block in it. It's been running smooth and I just replaced the fuel filter. After putting the new one in it took a lot of cranks and pumping to start. Once it started I looked back along the fuel line to see lots of gas being spurted out. Immediately I turned the truck off, traced the leakage back to the metal canister from which the fuel line comes from that connects into the fuel filter. On the metal canister there are two small holes. I don't know if they are supposed to be capped or what -- I assume so. I turned the truck back on and indeed verified that gas is being spurted out these two small holes at a pretty good pumping action.

This only happened right after I replaced the fuel filter (and had to pump and crank quite a bit in order to start).

Any ideas? Anybody know what these small holes are--if they should be capped/plugged? It appears that there are no hoses that should be connected to them.

Once again: the two small holes are on the side of a metal canister of some sort. The line going to the fuel filter is connected directly into this. And it appears there is another line going to the back--probably to the fuel tank.

I automatically assumed the metal canister is the fuel pump, but I'm not sure--I'm definitely not a mechanic.

Any ideas would be most appreciated.

-Davis

Any ideas would be most appreciated.

Please post pictures of what is leaking.

with out a picture anything would be a guess. Where is this metal canister in relation to the engine????bottom passenger side in front???

Looking at the OEM setup in LMC Truck's catalog there is nothing like you describe in the OEM system. Are you still using the stock mechanical pump on the engine? Where is your filter located, before the pump or between the pump and the carb, and does your truck have the cab mounted tank or the rear mount tank, or both? Like has already been said, post pictures of what you're looking at and somebody will have answers for you.

Yes. It is from the passenger side in front toward the bottom--apparently bolted right to the engine. Like I said, I'm assuming its the fuel pump.

Here's a link to a pic: http://risingtiger.sinkbug.feralhost...gine_holes.jpg

The two holes are circled in red. When the engine is running these holes are just pumping out the gas. Are they supposed to be sealed? Supposed to be hooked up to something? Can I safely try to seal them back up with something?

Lots of questions, I know. Hopefully you've got some ideas.

thanks,
-Davis

I'm not sure if the fuel pump is stock or not. The filter is located between the pump (what I'm assuming is the pump) and the carb. The tank is cab mounted.

thanks Roger.

The two holes are circled in red.


Those 2 holes are a vent for the top of the diaphragm in the pump. If gas is coming out of there the diaphragm has been damaged! Pump will need replacment and please verify that no gas got into the motor! Pull the dipstick and sniff the oil on the stick and if it smells like gas, replace the oil and filter ASAP! Also verify the installation of your filter! Did you kink the line thereby preventing or restricting fuel flow??? Does the filter have a check valve? Check it for operation! Maybe something caused some restriction and a higher pumping pressure hurt the pump or maybe it was just time???!!!???!!?? But check the oil for gas first!!!

That pump looks stock or "stock style" for sure.

Yep, like Mike says, that is a very old, and likely tired OEM style fuel pump and fuel leaking from those holes means the diaphragm is ruptured. Are you sure you put the fuel filter in right, with the flow arrow toward the carb? Regardless, you need a new pump and you need to at least give your oil the sniff test to be sure you were not pumping gas into the crankcase. Saw an old fella open his hood after smelling gas finding fuel spurting out over the fender with every pulse of the pump. He pulled out a kitchen match, whittled the end to a point and jammed it into the little hole, "fixing" the leak. Needless to say his engine was toast by the time he got back home that night....had about seven quarts of oil/gas mix in that old DeSoto.

Good thing is it's an easy fix - new pump from the local parts house, inlet & outlet fuel line connections to crack loose, and two bolts holding on the pump. If the pushrod slides down when you pull the old pump just slip it back up against the cam as you position the new pump & gasket, start your bolts and you're nearly done. Hook up the lines, tighten everything, start it up and check for leaks (after you're sure your oil is OK).

wow, that definitely gets to the point 34_40. Thank you for your response. I'll be checking the oil right away. It was probably just time for the pump--I hope. I'll be checking for any restrictions across the lines and filter.

thanks again. Most helpful.

cheers,
-Davis

When you change the fuel pump you'll have to be sure the pump rod stays up. There is a bolt on the front of the block around the corner from the pump. It is short and dose nothing but fill the hole. It should be removed and put a longer one in to hold the rod. After changing the pump remove the long bolt and reinstall the short one... If you have never done this type of repair I would recomend getting a book that covers your truck they cost about $30. and can be purchased at most parts stores. Good luck it realy isn't hard.Just sounds like it.

thanks guys for your feedback on this. I did the sniff test and indeed i've got gas mixed into that oil. Sure glad I didn't take the wittled stick to plug the hole approach!

My truck ran for around a minute to 2 minutes with this pumping spurting like that. Could that have caused some substantial damage?

You should be just fine. One or two minutes is not going to dilute your oil that much. Just change the oil & filter, get a new pump on it and you should be good to do. I had forgotten about Charlie's long bolt, short bolt trick (which works great) - I always just fought with it to keep the rod atop the lever. The bolt trick makes it even easier. Here's a video on the R&R process. http://www.youtube.com/watch?v=8XiuiyBAD8Q

Originally Posted by risingtiger

wow, that definitely gets to the point 34_40. Thank you for your response. I'll be checking the oil right away. It was probably just time for the pump--I hope. I'll be checking for any restrictions across the lines and filter.
thanks again. Most helpful. cheers,
-Davis

No sweat! Glad to help! I was only wanting to be really sure you understood the gas going into the oil part.

Seems like the other guys added some helpful tips too! So you've got a trip to the parts house in your future and then let us know how you make out!

Other way to hold fuel pump pushrod in place is to use grease.....let the pushrod slide down and slather it in chassis grease and push it back up. OR you can turn the truck updside down so the pushrod doesnt want to slip down.

mike in tucson