Double wall exhaust system, anybody do it ?

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mtnmankev

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It was a real treat today not to have to crawl under the truck in my nice go-to-the-big-city clothes and spray bottle the fuel pump to cool it off.
Several times after I had parked and shut the engine off, the pump made its clickety noises upon start up, but quieted back down as soon as the engine fired and started to burn gas.
At least at that level of sound, the mufflers will drown out the pump.
But when it was vapor locking, the fuel pump would drown out the sound of the mufflers.
 

DoubleDingo

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@mtnmankev I missed it, what did you do to fix it? Water spray at the push of a button like you mentioned? Or did you find a different fix to the problem? Vapor lock is a pain in the ass.
 

mtnmankev

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@mtnmankev I missed it, what did you do to fix it? Water spray at the push of a button like you mentioned? Or did you find a different fix to the problem? Vapor lock is a pain in the ass.

Since the electric pump did not have any kind of return line, I got a Wix 33040 fuel filter (should have gotten the 33041 for the correct fitting sizes but I tightened the **** out of the hose clamps and it doesn't leak) as suggested in a reply in this thread and now the gas has a way to keep flowing even when the needle and seat have gas flow shut off at the carburetor.
The constant flow through the electric pump is just enough to keep it cool enough so the gas doesn't boil and vapor lock.
Water spray at the push of a button would be my last line attempt to stop it, and a lot of extra labor to make that work.
 

DoubleDingo

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Since the electric pump did not have any kind of return line, I got a Wix 33040 fuel filter (should have gotten the 33041 for the correct fitting sizes but I tightened the **** out of the hose clamps and it doesn't leak) as suggested in a reply in this thread and now the gas has a way to keep flowing even when the needle and seat have gas flow shut off at the carburetor.
The constant flow through the electric pump is just enough to keep it cool enough so the gas doesn't boil and vapor lock.
Water spray at the push of a button would be my last line attempt to stop it, and a lot of extra labor to make that work.

Nice! Glad that filter worked. If you didn't need your truck so badly I could see you about to put some rounds through it out of pure frustration. :biggun:
 

mtnmankev

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And once again, this goes to prove how the combined knowledge of the members of this wonderful forum helps others solve issues they are dealing with.
I want to extend a hearty THANK YOU to all you kids who have contributed with your ideas, thoughts, experience, humor, and suggestions ........
 

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Definitely positive pressure.
I know if it had a vacuum the fuel pump would have trouble.
But if it had pressure (likely heat expansion) then the opposite could easily happen if the pressure was normalized with a tank of hot fuel then it cooled down. Probably just the gas cap.
 

Grit dog

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And once again, this goes to prove how the combined knowledge of the members of this wonderful forum helps others solve issues they are dealing with.
I want to extend a hearty THANK YOU to all you kids who have contributed with your ideas, thoughts, experience, humor, and suggestions ........

And thank you, as I was chasing a similar issue and the input and knowledge from this thread helped solve it.
I'm good on the vapor lock thing, cause 80 deg is hot here, lol, but plan on throwing a return filter with a return line on it if the truck ever has to work at high temps. (Plus I didn't know about those filters prior to this)
Again, glad shes workin good for you.
 

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I also read a thread where someone was having the exact same issue. It turned out their fuel pump had a shorter shaft than others for some reason. They were able to put a thinner mounting plate on it, which took the slack out and got rid of the ticking while still pumping. I still don't think you have a worn cam lobe because it pumps. If it was a worn lobe, you wouldn't have any pumping action and you still shouldn't have any ticking as it would wear the lobe off, not a groove all the way around the cam.
I've seen this more than once my truck has the same problem.Yes the pump lobe is worn out,yes it pumped fuel but enough.Verified it by removing the pump and holding the pushrod against the lobe at cranking speed and feeling the movement, I could of measured it with my dial indicator, but no need, I didn't have a1/4 inch of travel.When it first started happening I put a new pump on it which worked for a short while, when it quit providing enough fuel more investigation was neccesary. Kevin what I've done for cheap fast easy shade 4 pieces of conduit drill a hole all the way through on one end.Tie a tarp corner to each stick of conduit and 2 pieces of nylon cord. Now stand your sticks up pull them diagonal from each other and stake em off with the nylon cord.
 
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80BrownK10

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And thank you, as I was chasing a similar issue and the input and knowledge from this thread helped solve it.
I'm good on the vapor lock thing, cause 80 deg is hot here, lol, but plan on throwing a return filter with a return line on it if the truck ever has to work at high temps. (Plus I didn't know about those filters prior to this)
Again, glad shes workin good for you.
I heard about those filters about 6 months or more ago on a video posted on YouTube by Uncle Tonys garage. He said that those filters were the solution to your vapor lock on classic cars. He runs mopors so he was familiar with them but like said they work on anything.
 

mtnmankev

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I heard about those filters about 6 months or more ago on a video posted on YouTube by Uncle Tonys garage. He said that those filters were the solution to your vapor lock on classic cars. He runs mopors so he was familiar with them but like said they work on anything.

Well, I never once mentioned to my truck what the original application was, and it never complained , so all's good.
I appreciate you telling myself and the other members of the forum about them.
And I have the part numbers committed to memory for future reference.
 

80BrownK10

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I'm glad it got you back going cheap!
Well, I never once mentioned to my truck what the original application was, and it never complained , so all's good.
I appreciate you telling myself and the other members of the forum about them.
And I have the part numbers committed to memory for future reference.
 

Ricko1966

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Well, I never once mentioned to my truck what the original application was, and it never complained , so all's good.
I appreciate you telling myself and the other members of the forum about them.
And I have the part numbers committed to memory for future reference.

Pontiac used them, early 60s, through 1970? chevrolet used them on p chassis,corvair, big block novas, Camaro, chevelles etc. Your truck has no reason to be upset. I bet that 33040 would go on a 65 gto. AC/Delco number GF98. GF432 has threaded fittings for quadrajet application.
 
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