Looking for feedback on bogging down video

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Aug 5, 2014 | 01:24 PM

jomoflymo

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Joined: Jul 2014

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Looking for feedback on bogging down video

Greetings all,

I have been having some issues with my truck bogging down and stalling when underload. Wide open is fine but about 20% throttle and the truck bogs down and stalls. I have made a video showing the issue :

I have taken a lot of advice from people here about checking vacuum lines, jets, fuel filter, fuel pump, and nothing seems to have made a difference. I am hoping that someone might see the video and have some new ideas. My truck is a 1974 with the 460 engine, 4 speed manual. Pretty much all the vacuum hoses have been removed but this happened years ago and the truck has run very well until the last couple of weeks.

Any additional help would be appreciated

Aug 5, 2014 | 03:30 PM

fmc400

MSEE

Joined: Apr 2004

Posts: 10,386

Likes: 35

From: Austin, TX

Lots of vacuum leaks there. You can even hear them. Two right off the bat are:

1) Your breather hose is out in the open. The PCV system creates a "controlled" vacuum leak by design, but it expects the other end to be terminated with a breather filter. You're letting negative pressure escape by venting the breather out in the open.

2) You've got the choke housing completely open. Again, please refer to my writeup. There is a vacuum passage into the choke housing. When the cap is there, it seals off the vacuum source and there is a gasket in between. With the cap gone, you're pulling in atmospheric pressure straight through.

Fix all of these problems. You also need to run through the basics: check and set the points (that looks like a breaker distributor), set the timing, make sure the vacuum advance operates correctly. How long since the last tune-up? Plugs, wires, etc.

I strongly encourage you to pick up a Chilton's or Haynes manual to start learning the basics of engines and tune-up procedures. You really need to sit down and do some research for a while. Rather than create a thread every time something happens, it's much more to your benefit to educate yourself on your own time. You can't be spoon fed this stuff, and nobody learns it overnight. The forum is really intended to facilitate discussion about the things that aren't covered in all the common places: projects, aftermarket upgrades, reviews, complicated problems, etc. Not to be rude, but very few people here have the time or interest to continuously repeat the very basic principles that are covered in many books and online resources, especially since we all "work" for free. Quite the opposite in fact since I'm a site supporter.
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Aug 5, 2014 | 05:47 PM

jomoflymo

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FMC thanks for the info.

1) I will buy a breather filter and put that on there

2) The choke housing is only open because I am converting to a manual choke because my truck was missing all the pipes and manifold plugs to make it work.

I do have a Haynes manual and it has been very helpful for replcaing the plug wires and spark plugs etc. All of which I have done. However when it comes to carb stuff it is very general and the pics suck

Aug 5, 2014 | 06:37 PM

jomoflymo

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Also not to be rude but if you dont have time to respond to my post then don't simple as that. I think the public smackdown is a bit too much really. I am trying to be an active user of the forum which I would have thought would have been encouraged.

Aug 5, 2014 | 08:46 PM

fmc400

MSEE

Joined: Apr 2004

Posts: 10,386

Likes: 35

From: Austin, TX

Quote:

Originally Posted by jomoflymo

Also not to be rude but if you dont have time to respond to my post then don't simple as that.

This is the second time you've barked at folks simply trying to help you. The first time I gave you the benefit of the doubt; this time it's a little old.

What I'm trying to tell you, is that because folks don't typically have all the time in the world to field every single question and go into every bit of detail, the next best thing to offer is the simple suggestion to do some basic research on your own. I never said I didn't have time to respond; you said that. I said that the general user base of this forum does not typically have time to recite what's already all over the internet or at the library. Two or three times I've had to ask you to re-read a technical writeup that I provided to you.

I fail to see how that's a "public smackdown." My, and everyone else's responses to your inquiries have been purely objective and completely absent of any and all personal remarks or connotations. This is not an effective use of my time. I hope you are able to resolve your truck's issues.

Aug 5, 2014 | 09:00 PM

jomoflymo

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Senior User

Joined: Jul 2014

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Yes hopefully I will be able to resolve the issues and I appreciate all the help you have given. I just don't need to have someone bark a lecture at me