340 noise issue

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wlecat

wlecat

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Have a 1969 340 installed in my 67 Barracuda.
The engine sat for a long time, (owner said a couple of years), but I think it somewhere between 10 & 15 years to be honest.
Turned it for a long time without the coil wire to pump the oil around.
It runs ok but I can hear a distinct loud tap noise. Any Ideas what it is? And how to get rid of the cause.
Thanks for any help.
I made an mp4 video but it came out too large (147MB), trying to shrink it or turn it into an mp3 may try to post on utube.
 
WOW, you guys are quick, I'm worried it's a valve tap, someone told me the valve springs can lose tension depending on whether they're compressed or not, if they sit to long.
 
What I did for my 73 340 motor that sat for 11 plus years was poured marvel and sea foam in the cylinders and let sit for 2 weeks. Un froze the motor and no noises
 
video up
[ame="http://youtu.be/OK9pS24i79A"]http://youtu.be/OK9pS24i79A[/ame]
 
What is your oil pressure at idle?

Pull a valve cover and see if it has adjustable rocker arms.
 
Sounds like the hydraulic lifters bled down. It should go away after its run for a while. My tired old 360 that will be pulled soon does the same thing every spring. It goes away after it runs for 10-15 minutes and stays away as long as I start it regularly.
 
Thanks. Will check the valve cover & lifters. I need to change the oil and filter anyway. In the 70's I used 20w-50 GTX oil, still a good idea for a '69 340? Is it still available?
 
brad penn, valoline race, zinc additive. Sounds like collapsed lifter. Seafoam, marvel mystery oil. Don't drive it or rev it untill lifter freed or replaced. It will throw off the pushrod, then the lifter will come out. All oil pressure gone. Been there.
 
To me, it sounds like leaking exhaust manifolds! Easy to check by putting your hand around the manifolds to feel for hot exhaust gases blowing out. Maybe between the down pipes and the manifolds, because they don't use gaskets at these junctions.

If not this, then sticking lifters. Try seafoam in the oil. Then If that doesn't work, try Risolene oil flush and a new oil change and add Marvel Mystery Oil.
 
sounds like a wiped lifter/cam to me ...how much did you turn it over before it started did you prime oil pump??
 
Lifter noise,, it'll likely go away, change the oil,,,

I've always run 20/50 in my 69 340 since new, - and all my old, loose engines... my bet is it'll be fine.. my 0.02
 
Just pull the valve covers and measure the lifter clearance while running, just like you would if it was a solid lift car, it should become very obvious what the problem is.
add the marvel oil

or just physically touch each lifter while running until the noise goes away
 
Add a bottle of marvel mystery oil before changing the oil ,let it run about 15 minutes or so varying the engine speed.

Dump the oil and replace with Mobil-1 15w50,it has all the good stuff flat tappets need to live, just check their web site for the nay sayers.

Had numerous small blocks over the years and currently own a 340 I originally built in 1984.

If you let it sit over two weeks it would get a lifter noise at first start up that would go away in a few seconds no matter what oil was in it.

The worst was Castrol syntac,

After switching to the mobil-1 the lifters stayed pumped up no matter how long it sits

Been using the Mobil-1 in this 340 for over 15 years and recently pulled the engine apart for a head and cam upgrade and the cam looked excellent with no noticeable signs of wear
 
It had an uneven engine crank..... Lifter knocked out of it for sure... That might be why the old owner parked it. Might be cam and lifter time. But I would try the Marvel oil or SeaFoam. and see if it come around.

Just My 2 cents
Bob
 
Wow, that is loud...sounds like an exhaust leak to me (manifold).
 
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