Vacuum leak making "lifter noise"

M

Meat man

New member
I've been searching for the source of the noise in my 345. I have read up on all the oiling posts and I'm still going to investigate that further if necessary. It's always had a slight tick, but recently it has gotten worse and takes longer to go away after start up.


I was cleaning out my heater core today and happened to see a gouge in the vacuum hose from the intake (#8 runner) to the brake booster. I could feel a small leak, but when I messed around with the hose, the leak opened up. As soon as I did that, my "lifter noise" started but it was much worse. I had only heard it that bad once before. It sounded like the whole bottom end of the motor was going to come loose.

Fixed the hose, now we'll see how that noise is after a few days.

Nathan
 
Not really unusual on this old junk. Take it a step further and replace anything on the motor that relates to rubber!

Same kinda deal will occur with an exhaust leak from the two welch plugs under the intake manifold below the drillings for the egr ports in the exhaust crossover passage. Starts off sounding "liftree", progresses to "exhaust leakee"....sometimes. Mostly just sounds lifteree and minimizes once engine is fully up to temp...just like a lifter tick "kinda" goes away.

Stick a length of vacuum tubing under the intake manifold runners and fish it around while ya stick the other end in yore best ear. That's a redneck stethoscope...you'll hear all kindsa strange shit under there! Again...the open end of the tube goes in your ear, not yore mouth or nose.
 
I agree about replacing it, I had planned on it. The weird thing about it is that was a "replaced" hose already, almost a new hose. I can't figure out how it got the gouge in it, kinda in a weired place. Oh well, at least I found it.

Now that I think of it, I wonder if that is the cause of my stumble/stall after startup, only a few days of driving will tell me that. I guess that gives me reason to drive it.

Nathan
 
Hi guys and gals, I would like to re-start this thread, I am hearing the same tick, sometimes bad and sometimes not so bad.
I have had a few issues with brakes also.
Here is what I found, I pulled the hose off of the booster and plugged it the motor idled down and sounded great. Unplugged it and the noise got worse, put it back on the booster and the noise got a "little" better.
So I put a vac guage on and with the booster connected at idle I had 16" of vacuum. I dissconnected the booster and plugged the line and I had 16.5" of vacuum, not much difference.
I also checked the check valve and it is good. The vac hose to the booster appears good also because I plug it at the booster.

Having said that, does the booster have some sort of pressure relief valve in it or is there a leak in it? The motor just purrs when I have the booster out of the picture.

Ron
 
Never mind, it was definatly the booster!!! Swapped it out and the 74 just keeps running better and better!:thumbsup:

ron
 
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