I posted my question over in the big block forum but wasn't getting much of a response. I know there is always helpful folks in this forum, so figured I'd ask here too.

So....

My 460 is a mild build, using a D9 short block, D3 heads, Comp Cams XE262 cam with matching valve springs, stock push rods and rocker arms. I built the engine 8 years ago, it's got maybe 5000 miles on it now. It's somewhere in the 400+ hp range, it runs great.

The other night my wife and I went out for dinner with the truck. On our way home, we stop at a set of lights....there's a car full of kids in a Honda with a soup can muffler sitting beside me. Light turns green, kid floors the Honda, I ease into the 460 and keep it right beside him through 1st gear, so they can all hear the 460 through the flowmasters. I slap it into 2nd, and leave him in the dust.

2 miles later I stop at the next set of lights (Honda is MIA), but now I have a definite "tick" from the left side of my engine. The tick is noticeable at idle but goes away as you rev the engine. I nurse it home and shut it down.

At first I thought I may have an exhaust leak at the header. I had a buddy hold a rag over the left side tailpipe, hoping the exhaust leak would become more noticeable. The tick actually got quieter with the exhaust plugged. Now, I'm thinking valve noise.

I pulled off the left valve cover and everything looks good and tight. I rotated the engine through the firing order, bringing each cylinder to TDC, checking for slack/ slop in the pushrod/ rocker arm, finding none. I ran the engine with the valve cover off, the noise is still there. I put my hand on all the rocker arms hoping to "feel" the tick, but found nothing. All the push rods are spinning as the engine runs, some faster than others though? Then I noticed #7 and #8 exhaust push rods seemed to be wobbling as the engine ran. I thought, "ok, I bent a couple push rods, maybe I revved it a little high? (5500RPMish)" I took all the push rods out and rolled them across a mirror, and they all were straight?!

So, now I'm not sure if what I thought was a wobble in the push rod, was just my imagination, or is something else causing the push rod to wobble (Lifter, or rocker arm?) The rocker arms look ok, no obvious damage.

Not sure what to check next.....the engine still runs great too?

Sorry about the long post.

 

I'm no engine expert but my mind went right to an exhaust leak as well. Are you sure something simple like the donut didn't just blow out a little and when there is more pressure/flow it just rolls by? I'd be inclined to replace the header gasket and completely rule out the simple fix before I went any deeper into the engine. Just my weak .02

 

I had a fuel pump do that many years ago. The return spring had broken and the noise was the lever slapping the eccentric on the cam sprocket.
Good show spanking Honda !

 

I had a neighbour come over and listen to it for me. He's a mechanic by trade. He thinks it's an exhaust leak too. It's hard to get your hand in around the header, so tough to "feel" for a leak. I'll crawl underneath to see if I can have a better look for a leak. I feel better now that it doesn't seem to be an engine problem.

 

I'm in your corner hoping it's just an exhaust leak. My 1st reaction was a rocker arm stud pulled out of the head a tad. But you prolly have threaded studs there. How 'bout putting something safe down the carb while it's running that will make smoke come out the exhaust? Like slowly pouring tranny fluid. Maybe smoke signals show-em where leak is Chemosabe.

 

I'm going to try some sea foam. It's supposed to make white smoke.

 

Hmp, seafoam no white smoke, only from tire! Arizona gringo make sense. tranny fluid. Must dance to white smoke god after fluid in carb.
Video or it didn't happen

 

You might have a couple bad lifters. They will tick / click and make the push rod wobble. Try a thick oil additive and see if it eliminates the tick or makes it get less noticeable. over 8 years and only putting 5k on it. How many times did you change the oil and what weight are you using?

 

My guess is a leak at one of the exhaust ports. Tighten down the bolts on the defaulted side. See what happens. If no results, cut a length of garden hose. One end to ear, poke around with the other from above and below. If I am right, you will hear it loud and clear.
Not to rub it in pal, but who would you say won that drag race? You or the gaggle of pimple-faces in the Honda?

All in good fun,

Semper Fi

 

I do an oil change every spring when I take the truck out of storage. I use Royal Purple 10W-30. I have bigger problems now, check out my new thread......

 

Hey everyone!

I haven't been around for awhile since I put the truck away for the winter. I finished some home reno projects and was able to get back out to the garage. Anyway, I frigged around, checking this, and testing that, to try to figure out where the is ticking sound was coming from....

On my 460 there was an exhaust crossover pipe that ran from the back of one cylinder head to the other, it was part of the emissions equipment. When I built the engine a few years ago, I removed this pipe and plugged the holes with smaller sized freeze plugs. Well....the one on the back of the drivers side cylinder head worked itself out a bit after 7 years and developed a small exhaust leak! With the engine running, I can hold my finger over it and the sound (tick) goes away. EASY fix! I am so happy that I didn't hurt my engine.

On a side note, my short box just came back from body work. I'm ready to lift off the long box and prep to cut the frame for the short box. I'll start a new thread about the transition.

 

That is some great news!

 

Vacuum and exhaust leaks are real easy to find and pinpoint by listening through a section of vacuum tubing. I have one hooked to an old stethoscope, works great.

 

2x on the old skool listening tube.

Plus old skool can still be used on todays vehicles as well

2x+ Jeff's smoky fluids in the carb test

Short beds do have a nice look but, hate to see a long bed rare Mercury truck to be butchered on. As we don't see long or short here in the US of A
Orich

 

I do appreciate the wisdom and different opinions. I've thought long and hard about this. I do prefer the look of a short box in these old 2WD trucks. I also prefer the long bed 4x4's. When it came down to it, I had to admit that there was hardly anything left original to the truck anyway. The original 240 and 3-speed are long gone. A lot of the sheet metal had to be changed during the original restoration. It's not the original colour anymore, etc...... There just wasn't enough left of the original truck to justify keeping it original(ish). The only thing this truck hauls anymore is lawn chairs/ a cooler, and donkey.