Essentially, PCV valve in the back, routed to the "T" which is routed to the intake manifold and carb vacuum line, nobodies mentioned it before so I assumed it was normal, and when I replaced the carb I just kept the same routing, how should it be routed? Sent from my iPhone using Tapatalk
First you have a clamp missing from the intake. that's is certainly a likely vacuum leak. And the glass filter and rubber hose are a fire waiting to happen. I would check that the distrubeter is not worn out. the power valve in the carb could be sticking.
The filter and hose have never even got warm, I was concerned about it at first and I check it every drive because it makes me nervous, but even after an hour long cruise it was still barely warm. I do want to relocate it to under the cab when I replace those rubber lines though Sent from my iPhone using Tapatalk
So I took a video, I sprayed the vacuum lines and the intake / exhaust manifold around all the gaskets with carb cleaner, no revving or changes in how it runs, this was Coke at half choke, after it ran for a little longer the issue came back and I still can't pinpoint a leak *update* After letting it run a while, longer I sprayed where the vacuum lines meet the air intake and it revved up a little bit and never went down, not sure if that's related or not yet though, it hasn't fluctuated since then. *update* Took a lap around the neighborhood, drives like it did when the carb was brand new! Still want to pinpoint what caused it though, how would I inspect the power valve? is that similar to the vacuum advanced? I've never had to remove / re-install a distributor before, and if i have to, would it be a bad idea to replace it with a brand new one? I can get one from work for about $25.00, but i don't know how to set timing when removing one and adding another. I'm sure theres a how-to guide somewhere on the internet I can follow. Sent from my iPhone using Tapatalk
I thought the package said that it was some kind of polycarbonate blend or something like that, I might just get a regular 3/8 metal fuel filter when I'm ready to relocate instead of keeping this one then... Sent from my iPhone using Tapatalk
Yes, but that one sure looks like all the glass filters that I've seen. Maybe you got a new design, but the other ones are easy to break.
I'm thinking that that T in your pvc system might be causing a problem. The PCV valve needs to be hooked to a manifold vacuum source which could be a fitting on the manifold itself or a fitting on the carb below the throttle butterflies. Only one is necessary.
Cool, I can pull one side and cap it then run another and see how it runs, I think it would be better to use the one on the carb because it seems more reliable, the one on my manifold is a little 45 degree adapter and no matter how I run it, it goes between my air cleaner and valve cover Sent from my iPhone using Tapatalk
http://www.trifive.com/forums/showthread.php?t=151407 Never use a plastic or anything other than a steel filter on the line between the fuel pump & carb.
Dang, good to know! I know my carb manual says it has an internal filter, I think I'll just switch over to a large steel filter and mount it below the pump Sent from my iPhone using Tapatalk
M-m-m-m, I had the same problem once. Someone told me it was the carb. I had just rebuilt it but he said let's tear it down and I'll bet we'll find the problem. He was correct. The needle valve had a spec of grit in the way and one of the ball/springs in the idle circuit was put in up side down. After the clean and fix, it ran like new!
The sintered bronze filter that's factory installed in the carb inlet is darn good. The only drawback is its a bit small and when it gets clogged you can not clean it. I simply carry spare filters in my truck and tools to change it. I usually install a wix metal filter in the hose at the rear of the cab. that hose connects the steel line from the tank to the steel line running along the frame to the fuel pump. My daily driver working & abusing truck is a 66 GMC 250 six and granny 4 speed. I also have another 66 GMC with a souped up 250 and a powerglide.
The Jalopy Journal
