Technical 390 FE valve tap

Ok, I haven't posted pre diagnostic..

So on cylinder 1 exhaust valve with valve cover removed have a tapping.
Its oiling great.
I have a semi new rebuild approximately 400 miles.
Bored .060 over, all new bearings.
All new exhaust valves, resurface heads. New cam.
The rocker shafts have been replaced. New pushrods, new hydraulic lifters.
When the engine is idling I can put pressure (by hand)on the pushrod side of the rocker and noise gets louder. I can put pressure on the valve side and noise quiets down. I've swapped lifters, pushrods, rockers and noise stays at #1 valve.
The only visual difference at that valve is a different valve spring. I assume the machine shop saw fit to replace due to break or wear. Where's the noise comig from? Can a valve alone tap?!

 

Sounds like too much clearance, maybe the machine shop 'dressed' the valve stem too short. Have you tried sticking some feeler gauges between the rocker and the valve? If that fixes the noise, look into getting a lash cap for that valve.

 

Great idea. You either have to do that or get the next longer size push rod. I had to do that on one of my FEs years ago

 

I laid a straight edge on the valves and all appears right..not a good reference? (Every exhaust valve is a smidge lower than intake..if that makes sence).
Does the lash cap require machining the valve stem for proper seating?

 

Sometime you just get a 'tolerance stack' that can cause issues, that may be the case here. And no machining should be needed for a lash cap if the end of the valve stem isn't worn.

 

Have you talked to your machinist about it yet? Push rods come in a wide range of length and could be the cure as long as everything else is good. Who installed the 3/8" soft plugs in the lifter oil galley holes?
The Wizzard

 

I should have commented on the difference in valve stem height. IIRC, FE Ford rockers, lifters, and pushrods are the same for both intake and exhaust, so if the exhaust stem is shorter, that may be your problem. A longer pushrod or lash cap will fix it.

 

There are longer and shorter push rods available. Valve stem height should all be the same for exh. and intake but a slightly shorter valve stem height should be able to be made up with a longer push rod. A lash cap could fix it too but I've never seen one for an FE, but that doesn't mean they aren't available.

 

Could be a lazy lifter

 

Having different valve stem height can be a bad deal. There is a CORRECT rocker arm position that is dictated by the free length of the Valve Stem. When that is not correct neither is the amount the Valve opens. That can make for a very Lazy motor and faster valve guide wear. Correct Valve train operation is all about angles not push rod length. Were I you I'd be talking to the machine shop that did my work.
The Wizzard

 

Mrac41: I've tried a different lifter in that hole.

"The next size up pushrod" How do I know what that would be? I measured the current one to be 9.5625"
I've found new pushrods to order and here are the sizes available:
9.5910
9.5950
9.6210
9.6800
Is there a good way to KNOW what the next right size should be?
Other than buying all of them

 

The shortest one that will keep the valve train quiet without putting too much preload on the lifter.

 

RmK57: So it's gonna be a trial and error troubleshoot...
I guess I'll be buying the next few sizes and trying them...

 

If you measure the free length of the valve stem (it can be done with head on the motor) what the number under suggested stem height should be the amount longer than stock you would need. Now that is if your Cam is a new stock cam and not a re ground cam. When re grinding a cam the heel (lobe circle) is made smaller to get lift at the toe. That number also needs to be taken into total length of new push rod.
The Wizzard

 

You might consider a set of adjustable rockers. I happen to have a pair on the shelf.

 

Pist-n-broke: oooo that is tempting. Price?
I ordered the next three sizes up at a whopping $1 each (guess the kids won't eat this check)

 

I will be in the shop latter today and put my hands on them then P.M. ya. If you only have a one valve issue and a longer push rod on the way I'd say try it first but adjustable is often a good thing.
The Wizzard

 

An adjustable pushrod should work to get the correct length.

 

I agree, gonna tinker away. Looking forward to hearing from you. Got to keep these old trucks going. Most folks give up.
Btw I do love my old Fords. I have a 1966 F100 300ci, 1975 F150 390fe, 1976 F250 390fe, 1986 F150 300ci. The 75 was my first truck and still have her. Never for sale.

 

Check push rod to see if it is the same as the others. check wear in lifter bore

 

I installed the 9.6210 push rod this evening when I got home from work...still the same noise. The 9.6800 comes in the mail tomorrow. I'll try that one and report. (Note: "stock" length 9.5625)
On a side question to the same issue: what would be a symptom of a worn valve keeper (spring keeper)? Would that tap or would it just fall out? Surely the machine shop would inspect them closely or replace?! Right?!

 

Keeper and collar are a tapper lock. I believe it would only make one noise as it failed and dropped the Valve on to the piston. What kind of Oil pressure does this motor have? Front cyl. and front most valve makes me thing your not keeping the lifter charged. Who installed the plugs in the oil galley? Screw in or Drive in? That lifter is the furthest away from the Oil Pump. Who did the Final Wash of the block and with what?
The Wizzard

 

Pist-n-broke: The engine has 60 psi oil pressure. I won't put a business name on here. The machine shop did most of the work (.060 bore, new bearings, ground crank, new pistons, new cam, new valves, etc) I installed heads, lifters, intake, and accessories and installed engine in truck.

With a "tube listening device" in my ear the tap is coming from the top of the valve stem, contact to rocker area...
Very strange. I'm gonna install the 9.6800 rod this evening and post a report directly.

 

Well before I changed out the pushrod I'd fire up the motor and slide a .015 feeler gauge under the rocker arm and see if it quiets down. If not, installing the new one isn't going to be the fix.
The Wizzard

 

If a longer pushrod works, I would highly consider a lash cap to try to keep from throwing off the geometry more than it is.

 

Chrysler makes a lash cap that will fit a 3/8 th valve in different thicknesses .Thats where I have got them in the past . I have also found that using synthectic oil will make them noisy

 

Find out what it takes to get rid of the noise by upping the feeler gauge. your next length up you listed is over .10 of an inch. too much difference.

 

No comment on the noise issue, but I am interested in knowing something.
You said "...I've swapped lifters..."
Where they new, or used lifters you swapped in?
Only reason I ask is because the cam lobe & lifter wear in together on initial start up. You might be creating more trouble for yourself down the road.
-Dave

 

[QUOTE="Pist-n-Broke, post: 12716260, member: 1811 That lifter is the furthest away from the Oil Pump.
The Wizzard[/QUOTE]

Not on an fe. Front oil pump. This ain't no freaking chevy. :>)
Otherwise, I'd say your suggestions are spot on.
Farmalldan

 

Ok gents...
I installed the new rod to no avail...
Did some more diagnostics since the noise didn't change...here they are:
I put the engine at TDC and put 120 psi in #1 cylinder, removed valve spring. SINCE this spring is different from the others (dual spring type) I could see rub marks on inner spring.
I removed inner spring and reassembled. Same noise...
I'm thinking possible a valve guide...hell I dunno. It isn't a loud noise so I'm thinking of driving it a bit more and seeing the outcome. Brothers-in-engines! I can't firmly say it's something bad...