Greetings,
I am tracking down an annoying "ticking" on my 1975 Highboy, C6 FE360 engine. I am trying to rule out exhaust leak at the manifold to head, exhaust donut leaks and the valve train itself.
Top end had 63K ORIGINAL miles was rebuilt by me approximately 3K miles ago. The ticking while not too bad, is definitely getting progressively worse. The rebuild included rebuilt stock ford heads, with new valve/springs. I did not replace the cam and the lifters were not removed(which may be part of the problem) pushrods were all verified straight and replaced in their original locations.
Today I re-torqued the manifold to head bolts and found none loose.
The exhaust donut took about two turns on each nut which appears to have quieted down the majority of my ticking for now.
While validating that I had correctly located the "thinner" bolt on the rocker shaft, I was running the engine with no valve cover on the DS. I noticed that one push rod(3rd one from firewall) has an excessive amount of oil flowing down the pushrod versus flowing into the spring.
Does this indicate a problem with my rocker arm assembly on that cylinder or is this how its supposed to act? Other push rods on that head all seemed dry with the oil going to the spring side versus the push rod side.
I couldn't really identify any louder ticking in that area though, just curious.
Thanks in advance
Tbruz

 

 

Perhaps the exhaust donut needs to be replaced. ??
Sometimes certain noises can be isolated by using a mechanic's stethoscope or a piece of hose held to the ear.

 

Tedster9 : The ticking definitely increases under load and almost goes away as I let off the accelerator; plus I got 1 to 1.5 turns out of the tightening effort on the exhaust donuts. That make an exhaust leak more likely than any valve train/lifter tick. Also my exhaust system is not isolated from the frame by any rubber mounts. The exhaust shop welded the the hangers on the front pipes, which bolt to the stock manifolds directly to the frame. Wondering now if this "rigidity" is causing the donut bolts to loosen up?

ozzieh : I've replaced the Felpro fiber donuts with steel ones already. Also, not hearing any leak anywhere at idle using a mechanics stethoscope. But thinking now that the rigid mounting of my front pipes may be the cause of the leak as the motor torques under load and the pipes cannot.

Thanks
Tbruz

 

I would check that rocker arm to make sure all passages are free from buildup.

 

That's a good point. Most systems have some sort of flexible "hangers" for the exhaust, as most engines move a little when running. You could try some locking washers or lock nuts, but if it gets too rigid, something may crack.

 

More like causing the joint itself to loosen up, which makes the bolts become loose without them ever turning counter-clockwise.

Something has to give as the engine moves around normally, and the pipe joint itself could be the path of least-resistance, depending on the strength and arrangement of the hanger system. And if it's all rigid enough, it could cause the exhaust manifolds to crack, and that ain't any good.

 

Every 360 we ever had sounded like this because of exhaust manifold leaks. It's a common issue on these engine. Sometimes the leak is between the manifold and the head.

 

Ford did not install exhaust manifold gaskets on FE engines (excepting 406/427), only stainless steel heat shields.

Over time, the manifolds begin to warp, so the tick - tick - tick begins.

Aftermarket exhaust manifold gaskets are available from Fel-Pro, Victor and etc.

This ticking jazz affects all FE engines installed in cars and trucks, not just 360's.

 

That makes sense then. I always found the sound nostalgic and endearing. FEs have their own sound and for me at least, the leaky exhaust manifolds are part of it.

 

Thank you!!! I have been going crazy thinking about exhaust leaks for a while, you cleared the mud!!!

 

I rebuilt the DS rocker arm thinking that reduced oil flow within the shaft may have been contributing to my "ticking" sound.
While I did remove a bunch of sludge from within the shaft, The ticking continues even after having snugged up the exhaust donut nuts.
Again its only under load that I hear anything.
Giving up for now.................unless anyone has any other suggestions.
Thanks
Tbruz

 

Pre-ignition?

 

If you do end up replacing the exhaust gaskets, I highly recommend Remflex gaskets. I've used them on many different applications and have never had a leak.

 

Wentzmetalworks: I've been thinking about switching out the manifold gaskets as another area to rule out for potential leaks.
I can't seem to find an exact application for a 1975 FE360 with stock manifolds.(i.e NO headers). The stock manifold ports are 1.36" wide x 1.96" tall.
Closest application I see is their PN 3008, unless I'm missing something. PN 3009 seems closer from a port size but it say for headers only.
Can anyone advise what PN they may have used.
Thanks
Tbruz