New to forum. Need help with mystery valve tick

[Travisbraz1]

I'm new here to forum. And new to the flathead world. Last year I got a 55 Dodge truck with a Plymouth flat 6. the engine was a pro rebuilt engine with about 5000 miles on it. In 1983 when it was pulled and stored in a heated garage till last year.it was bared over and oiled every newyears to prevent seazing.I have now reassembled truck and engine runs good,had no noise first few trips around neighborhood. But now has developed a tick in number 1 exhaust tappet. But comes and goes. One day it will be gone and next it's back.I pulled inner fender and checked valve clearance if it was at about 016 It would quiet down with feeler gauge in. If I set it at .012 and it still ticks went a little tighter and it got quiet at idle but would rattle worse when rpms went up.and I do know not to run them too tight from reading on this forum.but think I may have a sticking valve from sitting??? Week spring??? The engine is very clean inside. No sludge at all. Like new.I am running 10-40 with a little Lucas in it. Any input on this would be greatly appreciated.

[NiftyFifty]

Sounds like maybe a worn spring if you can't get it to hold or stop ticking with adjustment, but you may also consider running something like Marvel Mystery Lube or Seafoam in the fuel and see if it goes away...may be a dry valve, and this junk ethanol fuel doesn't help that. I've got a tick in mine that I've never been able to make go away, I've concluded the same issue...weak spring(s) and lousy fuel...because I swear it's not as loud on premium, but I also add the MM to my fuel, so might just be that.

[Young Ed]

Verify the adjuster is flat. I've heard of them wearing a depression in the top. When you put the gauge in there is covers it giving you the reading you want but in reality the valve stem is going down into the adjuster and giving you more clearance. 

[Travisbraz1]

Verify the adjuster is flat. I've heard of them wearing a depression in the top. When you put the gauge in there is covers it giving you the reading you want but in reality the valve stem is going down into the adjuster and giving you more clearance.

[Travisbraz1]

OK I will check for that. Hopefully not due to engine only having 5000 miles on all new 30 year old rebuild. But anything is possible. I was running it some more with valve covers off and am noticing theat all tappets spin in unison while running. Except for the one making all the noise.it don't spin at all.. Kinda odd and swear I seen it almost hang once or twice. But I can't figure out why it would be hanging in a engine theat looks brand new internally. No sludge or rust. Just shiney new metal. And has not been ran long enuff for wear in valve train. I may try marvel oil before taking head off. I have to get to bottom of this. I can't live with it. And won't drive truck till it's right.

[pflaming]

Be thankful you can HEAR the tap, tap, tap!, LOL. As an after thought, it might be a Raven.

[greg g]

Can you rotate the lifter manually? Maybe if you give it a quarter turn or so it might start rotating on it's own like it's supposed to.

[Jeff Balazs]

I don't think this is all that uncommon with an engine that sat for a long period of time. I know mine sat for something like 30 years and I had a couple of noisy lifters to begin with. That all went away with use and a few short duration oil changes. One thing I do that I think is very appropriate for these engines Is to add a little bottle of STP high mileage formula additive to the oil. Has a good blend of additives.

 

Jeff

[Travisbraz1]

Well I can't believe it. I pulled sparkplug and put a few oz of marvel mystery oil down hole. And some in a small bottle and soaked tappets and valve stems and springs and let sit over night. Then I dumped rest of bottle in oil and in fuel tank.when I left last night I had set number one exaust to .012 when I came out this morning it was tight!! Valve was sticking and not returning all the way. I re adjusted valves and drove. It runs amazing. No ticks or misses. Flawless. I can't believe how well that worked. Mmo is awsome. I will run it all the time

[Jerry Roberts]

I use MMO also . When I was checking prices Walmart had the best price . 

[MBF]

I bought a 46 Dodge truck a couple of years ago that was running on only 5 cyls.  I could hear the lifter clicking, and I was pretty sure the head would need to come off.  I know that these flatties are well known for hanging valves after sitting long periods of time.  I had one that was so bad it had pushed the guide up a bit.    I took a chance and gave it a drink of MMO slowly down the throat of the carb, and then choked it off with it.  While I was picking up tools I heard a clunk.  I started it back up and had all 6 with an occasional miss.  I put some MMO in the gas, and when I did an oil change I put some in the oil.   Miss was gone, never hung that valve again while I had it.   Running it was the best thing for it.    Good stuff-

[Travisbraz1]

Yes it seams to be good stuff. I ran truck yesterday for a hour or so and a little today and it is running amazing. It is smoking a little. But I gave it a double dose in fuel. I am a diesel mechanic for a living. And always laugh about people trying to find mechanic in a can. But this is as close as it gets. I was ready to pull head. And would of spent hours doing what this did overnight while I slept.I am impressed. I know from reading on here, theat I don't want to run valves too tight.and should hear some chatter. But I hear none now with valves set at .012 exhaust and .010 intake. My motor is a Plymouth car motor. So from what I have read that is on the loose side for a car engine.

[RobAr]

Quick story to share. I started "resurrecting" Penelope two year ago. Fired her up in June, 2014 after 30 years in storage (I've owned her since '67) and she started right up, but things have proceeded in fits and starts since. Money accounts for some of this, but life in general just gets in the way of spending significant time on the project. 

Anyway, after rebuilding brakes (with a friend's help) throughout, and actually licensing her for the first time in 30 years, I was working on floor cancer and  a new gas tank (used a modern fuel cell rather than trying to resurrect gummed up old tank) Penelope suddenly developed a knock - bad enough that I didn't want to run for fear of doing real damage. Had several friends check her out and everybody had a different take, so the project went back on hold back in June. She's been sitting on blocks in the garage since then.

Finally, with winter layoff and cold weather precluding outside work I fired her up and listened again. After listening with a scope at different places and doing a full rebuild on the carb to address hard starting I came back to this forum and Youtube. Bottom line was I decided the most likely culprit was a stuck valve. Before tearing the head off, I decided to try a couple other options. Based on Youtube testimonials, forum posts and friends' advice here's how it went;

1) Bought a can of Seafoam and dug up a liter of ATF I had kicking around along with a liter of warm water.

2) Started the car and warmed her up (it was -15C or so), then fed the following down the carb snout while maintaining idle and occasional throttle goosing to clear the pipes. In rotation, I used Seafoam, ATF, then water. Probably 6 full cycles of this over half hour period, using a full can of Seafoam and a liter each of ATF and water.

3) After about 15 minutes, there was a sudden clack and rattle from the depths of the engine, and I thought it was going to stall. Figured I had really done a number on her. But then she smoothed out and just started to purr! The knock was still there - but I have to listen really hard to just sense it below the natural rhythm of the engine. My guess is that carbon deposits causing the hanging valve (or whatever) had broken loose and chewed their way through. There are probably remnants at the problem site and this is what I can still faintly hear, but basically, the engine is back running smoothly enough that I'm motivated to get back on the cleanup (replacing cracked wiring and such) and cosmetic aspects of the project (gutted interior because mice had destroyed it).  

4) Ran the engine for another hour following this treatment. No smoke, no blowby, idling along as is nice as you please. Penelope's on track again to make it into the July 1st parade in my small town where I first drove her fifty years ago (summer between grade 11 and 12). 

Bottom line? Hard to tell if it was the Seafoam, the ATF or the water, but the combination seems to have done the job - and saved me the time and money for a top-end job. More time and money to spend on the million other things I need to do before Penelope's back fully "road-ready".