SOLVED: HORRIBLE annoying engine tick after heads and cam. Need help!!

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93dakman!

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CAUTION: LONG WINDED STORY AHEAD.........

what I have is a 1984 flat hydraulic 318. I would like to consider my self a pretty savy engine guy but I am very VERY stumped on this.

I will start with the build which your more than welcome to skip over and just read my whining below.......

I had a set of magnum heads left over from my 360 that became a 408 with Mopar r/t heads. I decided to set out and put those heads on my '84.

Max valve lift on these heads is somewhere between .525 and .550 (depending on who you ask) due to the valve to retainer clearance. I put mopar valve springs on with hughes retainers. The heads were in good shape. No noticeable problems, valve seats appeared to be good.

I put those heads on with a set of Mr. Gasket 1121G head gaskets at a 0.028" thickness.

The cam I chose was based on the mild duration and mild lift with an emphasis on the exhaust which really helps the magnum head; and a lsa of 112 to keep a broader power range with less overlap. The lunati 60402 (220/226 duration at 0.050, .475/.494 lift on a 1.5 rocker) fit the bill. At .507/.527 lift In/Ex on a 1.6 rocker they work great. I put brand new melling 0.904 AMC oil through hydraulic flat lifters on the cam. (Did not prime prior to install)

Following the lifters I took the advice of 3 forums that stated that the correct pushrods for a magnum headed LA engine are Ford 351w stock 5/16 7.634 pushrods.

I am using the stock pedestal 1.6 rockers. Using these pushrods I could not get this engine to start. At first I couldnt figure it out. After screwing around for a good half hour I figured out (after pulling out the dial indicator) that these pushrods are keeping the valves open .087". I took these too long pushrods out, and cut 4 of them in half, removed a half inch of length, tapped the inside and made a set of locking measuring pushrods. Using these showed that at zero lash plus 0.025 I needed a 7.600 pushrod. Installed these and the engine fired right up. Now running, I broke this cam in with a good coat of lucas moly smeared over the lobes and VR1 racing oil (high zinc content)

After break in I have drove this truck for 500 miles and have a ticking since initial start up that is driving me crazy. Its loud, its noticeable and it sounds trashy.

I have done everything I can think of to solve this.

I started with a 1/2" 3 foot hose up to my ear to find the noise. #5 cylinder, intake. I could not hear the ticking while putting the hose to any of the exhaust/header gaskets. I could not hear the noise near any other of the 15 rockers. ONLY on this one rocker could I hear the noise. So I pulled the rocker arms and swapped them around to see if I had a butched up rocker. Ticking stayed on the same #5 intake. So, I took the rockers loose and did the same with the pushrods thinking that there may be a too short pushrod as the culprit. Swapping 3 different pushrods in didnt change anything, still on #5 intake. So I put in a ford 351w pushrod (same diameter, just .034 longer), still no change. Then I thought oh great, the cam lobe. I pulled the intake and looked the lobe over and it looks absolutly perfect, no wear. I then had autozone same day ship a new lifter (same as the others in the engine) to place in, thinking that the lifter collapse or had excess tolerances. Put everything back together and found that the ticking actually got louder. Im now getting annoyed so I call it a night. So, i come back out this evening to try more. I swapped rockers and pushrods around again (because its so easy), no change. I put a few feet of silicone hose in the compustion chamber through the plug hole, brought the piston to top and proceeded to pull the valve spring off of both the intake and exhaust of this cylinder. Intense inspection revealed no wear or damage on either spring, inner or outer. Put the dial indicator on the valve tip perpendicular to the length, just to measure any side to side wear of the valve or valve guide. Found nothing, barely even measurable. Swapped the springs from intake to exhaust and reinstalled. Checked for rocker to spring retainer clearance; miles of clearance. Checked for coil bind; not even close. Checked for retainer to seal; plenty of space. When I place the hose to my ear, I can only really hear the ticking near the valve side of the rocker arm, not on the pushrod side. I am at a loss, I have no idea what I am missing or what could be



Heres a list of parts:

Cam http://www.lunatipower.com/Product.aspx?id=1544
Head Gasket http://www.summitracing.com/parts/MRG-1121G/
Valve Springs http://www.summitracing.com/parts/DCC-4286813/
Retainers http://www.hughesengines.com/Index/products.php?search=1278&partid=23197
Lifters http://www.summitracing.com/parts/mel-jb-2011
Starting Pushrods http://www.summitracing.com/parts/edl-9656/overview/
Final Pushrods http://www.summitracing.com/parts/cca-7959-16/overview/
 
After cam break in, I changed the oil and went with VR1 oil.

I have never had an oil pressure issue. Even though I only have the stock dash gauge, it climbs from start up to midway and doesnt move any more or less than one hash mark up or down at any given RPM.

I am stumped. The noise has a tendency to get loud, quiet down or temporarily go away. This is in no way related to RPM or engine temperature. It will do it cold or hot, at idle to WFO.

It may start ticking loud right away and stay that way for 5 miles, quit for 30 seconds and come back just loud enough to hear over the tires and stay until i turn it off.

Or it may tick just enough to be heard and stay that way for the entire trip.

All 16 rockers are getting oil through the pushrods to the rockers, even the offending loud rocker.

I cant see it being a lifter or spun cam bearing issue since it has great oil pressure and still oils up to the rockers.
 
This sounds familiar to me, bought a complete set of new lifters, problem went away. How can you be positively sure you have the right lifter?
 
I've read thru you posts several times and now "I'm" ready for a nap...lol. Can't imagine how you feel with all the work you've done :banghead:.

You already covered just about everything that would jump out at most of us. The fact that the sound seems to be at the valve end surely would be loose valve clearance on the surface, but you've covered that at far as I can see.

Now that this is in my head, I won't be able to stop thinking about it, so if I come up with something, i'll let you know?

Good luck. A lot of smart guys here, so hopefully we can get it done...:thumbrig:
 
About the only 2 things you didnt mention are; A loose guide in the head, a valve sticking in the guide, and an ill fitting rocker arm to pivot shaft. Oh wait thats 3 things. You also didnt mention valve to piston clearance, but thats hard to imagine.
The statement about the noise being not temperature sensitive pretty much rules out a guide problem, so Id check the rocker arm to pivot clearance, even though I doubt thats it.
IDK, really.My first thought was pushrod to tunnel, but you said thats not the noisy side.
Well, there is one other thing. If the valve seat is not concentric with the guide, that could put the valve slightly off center with respect to the valve centerline. That would cause the valve to hit the edge of the seat somewhere, then slide down and center itself, effectively bending the stem. Were talking a couple, to a few, thousands of an inch here.I suppose that could manifest as a ticking.
Can you tell Im grasping at straws here?
 
Also too could be an obstruction in the oil galley at that lifter. Although I would imagine it would effect more than just the one. You never know. Lastly, what kinda work did the heads have? I have seen loose valve seat inserts make noise JUST like a lifter.
 
If I read this right you are saying rpm is not a factor and the noise frequency remains the same at varied engine speeds. That seems odd. If I had to guess I would think the problem lies in the valve. Maybe a little gummed up from sitting, in which case a little additive to clean it up might help. I had a non Mopar that ticked when the rocker hit the cover, but if you only hear it at the valve side probably not your problem.
 
Do a compression check.

I am betting you wiped a lobe, even if it looks great.
 
And I'd stop using internet forums for stuff like push rod length. It's easy to measure.
 
I didn't read your whole post, but if those melling lifters are not for the AMC engine and you didn't use oil through pushrods, you have no oil to the rockers on a Magnum head.

Okay they are oil through pushrods.
 
I bet the answer is somewhere in here. After all the changes you have made to get the answer the only things in common any more are the cam lobe, head, valve, and rocker shaft, assuming you have isolated the noise correctly.
 
Spring retainer hitting a guide?
Too short or too long of push rod(s)?
Rocker hitting valve cover?
Did you check all the lifters and the lobes?
 
Have you run it without the left side valve cover? Any signs of interference with it? How much preload do you have with the 7.600" pushrods you have now?
 
Magnum heads are designed for taller roller lifters and the associated pushrod angles. Check where the pushrod goes through the head and see if the pushrod is "brushing" the side of the pushrod hole causing your tick.
 
I agree with the last post ,possible it had the oversized lifter bore ,what did the block say on it in the serial#

or does your head have valve seats in it ,when there loose and moving they sound just like a lifter tap
 
teringer said:
I agree with the last post ,possible it had the oversized lifter bore ,what did the block say on it in the serial#

or does your head have valve seats in it ,when there loose and moving they sound just like a lifter tap
Click to expand...

engine serial # pad left bank, is there a diamond symbol stamped on the block? If so, one or more lifter bores are oversized.
 
hi am new to your site. I don't know if this will help you or not but had a vehicle that would tick at startup and would really get loud when you got on it driving down the road. then at a idle would sound like a header leak and do it daily. it ended up being the shaft from the oil pump to the dist. jumping up and down. the oil pressure never fluctuated it ran high all the timesoo I was wondering when you had dist out if you noticed any signs of excessive wear or play in dist shaft side cto side or up and down more than normal or wear on teeth or slot on bottom of dist. just trying to help out.... thanks
 
sivercity51 said:
hi am new to your site. I don't know if this will help you or not but had a vehicle that would tick at startup and would really get loud when you got on it driving down the road. then at a idle would sound like a header leak and do it daily. it ended up being the shaft from the oil pump to the dist. jumping up and down. the oil pressure never fluctuated it ran high all the timesoo I was wondering when you had dist out if you noticed any signs of excessive wear or play in dist shaft side cto side or up and down more than normal or wear on teeth or slot on bottom of dist. just trying to help out.... thanks
Click to expand...

Welcome to the site!

Good point. Don't some people use a stop collar to help prevent this?

Leads me to think, how is the oil drive bushing?
 
I had a flexplate crack on a 904 once and it had a constant tick. That one took a long time to find. Something else to look at.
 
Roller tip rockers 1.6 ratio?
Have you looked at the pattern on the top of the valve stem?
 
Thank you sledger46, you save the day. This problem is SOLVED!

I really REALLY appreciate all of the help and ideas to check. And the quickness of your replies. Thank you!

Really the only thing I can blame is myself. I assumed (and you know what assuming does!!!) that the heads were bolt on and the only changes I would need were lifters pushrods and the proper intake/gaskets. I made sure the valve to piston was good and I sized the cam for the retainer clearance. The issue was my negligence in checking the pushrod to head clearance. The problem area is on the intake face side of the pushrod hole area. If you have done magnum head swap, I am sure you are aware of this problem. If you are planning this swap and are gathering information, here is the deal:

The geometry of the LA's short lifter vs Magnum tall roller lifter valvetrain.

First off, the pushrods do not sit plumb out of the lifters and the pushrods do not come into the rockers plumb.

Alot, but not all of this is due to on the magnum engine, the tall roller lifters put the pushrods further away from the head. On the LA engine, the head has more proper clearance in the pushrod area for the longer pushrods/shorter lifters and the geometry imposed on all of these parts.

What you have is the lifters sitting in the block at an angle from vertical greater than the pushrods. So when the lifter and pushrod is on the base circle of the cam, the pushrods are directly contacting the heads. Then, when the lifter starts running up the ramp of the cam, the pushrod is moved further away from the head. This geometry issue is also why it is known that a cam with .3125 lobe lift will not produce a true .500 valve lift (with a true 1.6 rocker). When the lifter starts running down the back side of the cam lobe, the pushrod comes back into contact with the head and consequently pulls the pushrod off of the cup in the lifter. As the cam rotated, the pushrod would slam back in to the cup and thats where I was finding my ticking.

I must have missed all of the signs. This is what I found upon a closer inspection:

The comp hardened pushrods showed a slight wear ring midway up the length. I thought it was the head gasket or something else. I would have thought that metal to metal contact would have shown more wear on the pushrods than that. Hardened pushrods.....

The tip of the pushrod that was in the lifter had a very bad place of wear about 3/16 of an inch above the very tip. This corresponded with the wear I found on the lifter that I took out and replaced (when I thought the noise was a bad lifter). The lifter had wear on the inner diameter of the outside lifter body, clearly where the pushrod had been sitting on the outside of the plunger, up against the inner wall of the lifter body.

Also, I noticed when the valve covers were off, I would see intermittent rocker oiling when I could hear the ticking.

So when I started this adventure last night to solve my tick, I started by pulling off the noisy pushrod and rocker. Thought about what damaging effects this could have on head gaskets or whatever else and decided to do it anyway. Started the engine and the ticking COMPLETELY went away. So that eliminated the idea i had that a foreign object may have got on top of the piston. It still did not eliminate the bent/sticky valve or seat problem. So I looked down the pushrod hole and saw a shiny spot on the intake flange side that corresponded with the wear on the pushrod. Great. I drained the coolant and pulled the intake for the 4th time. I loaded the entire valley with dry towels. Then I piled a handful of clean oiled up rags under the hole I would be grinding in. Did the same thing to the top of the head. I was refusing to pull the head to do this. Although head and exhaust gaskets are cheap and the coolant was already drained, I wanted this thing to run tonight. It was a bad decision to grind on an installed head but I will live with any problems. Please, grind your heads while they are on the bench. I did not want to use the die grinder because it turns so fast and shoots metal shavings in a 3 mile radius. My choice was a cordless drill and a 1/2" double cut cylindrical burr. I could vary the speed and had good control with this set up. There is a very large amount of casting flash half way down this hole. Not only that, but the wall there also starts to bulge. Take this entire area down flat. It wont be more than 5 minutes of grinding to take enough material off. It doesn't have to be pretty. One it is clearanced enough CAREFULLY remove all of your rags/towels. Soak a few paper towels in oil and wipe the area down to pick up any remaining shavings. Then stuff towels in the valley under the head and spray brake clean in to make sure all metal shavings are removed. Wipe down with brake clean soaked towels until no shavings comeback. Reassemble.

This procedure cured my loud ticking on the drivers bank of the engine. However, now that I don't have that noise, I can hear slight ticking on the passenger bank of the engine. Bummer.

Again, Thanks for all the help and ideas you guys gave me.
 
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