Valve lifter question ....

[Pete]

Originally Posted by john mullen

Not knocking modern technology but even having the valve seats done on a modern machine it's a good idea to lap the valves in. The spring pressure ( flathead) is not as high as a modern engine and they need to be seated really well ..I lap in all valve work no mater what type just to see where the seat contacts the valve...Don't want comebacks it hurts my wallet..LOL

Everyone has their own way of doing it wrong. It may work but it is not as good as modern machines can do it.
Valves done on a modern machine are vacuum checked and will hold vacuum as long as you want by their own weight on the seat.
Lapping after machining will actually REDUCE the sealing ability.

[Karl Wolf]

I was taught early on to use an interference angle, that is cut the seat @45 degrees and the valve @44 degrees. This gives you a knife sharp sealing edge at the outside of the seat... This will work in as the engine is used. Will not change the valve adjustment much at all...

Karl

[john mullen]

As I said I'm not knocking modern machining. each to his own it's just my way of doing it...

[HotRodmicky]

Originally Posted by Pete

Everyone has their own way of doing it wrong. It may work but it is not as good as modern machines can do it.
Valves done on a modern machine are vacuum checked and will hold vacuum as long as you want by their own weight on the seat.
Lapping after machining will actually REDUCE the sealing ability.

I think Vern only wanted to make sure and check that
The seats where ground correct width

All the seats already looked clean in the block in the beginning.

And i don think useing fine lapping compund for checking will
Do any harm....

[JWL]

Using lapping compound can give false, miss-leading, and wrong information about the very subject you are trying verify. I suggest the users re-think their habits.

Just the thickness of the compound application makes it completely useless as a method for determining or verifying a seat.

Yes, I know, you have been doing it that way for 63 years on 12,000 engines and they all ran perfectly for 227,000 miles. So, either learn or ignore. Your choice.

[Ol' Ron]

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John, I'm glad you posted that. So many peopel do this I was beginning to doubt myself. 40 years ago I was told to use bluing for a better idea of where the sear was. Now I just use a marker pen. Keep the exhaust near the edge of the valve and break the edge.
Take car.

[Ronnie]

50 years of bad habits "LOL"

Hard to beat that hi tech marker isn't it!
I prefer to us a red one as it transfers easily. Jmo

Cleans up with brake clean.

R

[Charlie ny]

Just my 2 cents....I purchased some NEW Johnson adj's...these were still in the box
wrapped in onion skin paper around which was news paper dated 1954. I installed
them after drilling the bores and and cranked them into adj'mt with some effort. The
goofy 'wrenches' supplied were next to useless.....'54 technology might not be so
bad.
Charlie ny

[john mullen]

Yeah Charlie ny I'm old skool too ..Its hard to teach an old dog new tricks ...LOL.. but some new things do make sence...

[HotRodmicky]

Originally Posted by JWL

Using lapping compound can give false, miss-leading, and wrong information about the very subject you are trying verify. I suggest the users re-think their habits.

Just the thickness of the compound application makes it completely useless as a method for determining or verifying a seat.

Yes, I know, you have been doing it that way for 63 years on 12,000 engines and they all ran perfectly for 227,000 miles. So, either learn or ignore. Your choice.

Having a bad day?

So what is a good way then to check if the valves and seat match and the work
Was done correctly?

I like to learn....

[john mullen]

When you get your valve job back Lay the head with the chamber up and put lacquer thinner in it and look into the port and you will see just how good a job you got. I don't think there is a machine yet made that can do a seat that will pass this test. Therefore the need to lap the valve's to the seats and if done right they will pass this leak test. Don't take my word for it ,try it for yourself. I'm sure there are some here who will debate this and that's all right with me . Sure the machine only valve job would eventually seat themselves in after a time of run in and wear. I think they are done today without lapping because of the extra work and time it takes. More time spent= less profit made. I call it workmanship well done to those who still take the time to do it this way ...I think it's the edge between winners and those who also ran... JMHO

[Bassman/NZ]

Originally Posted by Ronnie

Me too!! talk about rudimentary!!!! Wow. This is 2014 not 1950 "LOL"

R

In the 40s and 50s guys like Brown were driving their flathead roadsters to the lake, running 125 or more, and driving home. You telling me they were doing it wrong? I dont think so.

[john mullen]

^^^^^^^ I'm with you Brother ^^^^

[Ronnie]

Originally Posted by Bassman/NZ

In the 40s and 50s guys like Brown were driving their flathead roadsters to the lake, running 125 or more, and driving home. You telling me they were doing it wrong? I dont think so.

You need to get with the times yes it was done that way because it was all they had. Do we still have the pony express?Machining techniques get better.
Lapping is stone age believe it or not.Not once in my posts you will find any reference to wrong.

R

[Brian]

I too do it wrong...apparently! I actually go one step further; I lap my valves with torque plates affixed to prestress the block as it is when assembled. Why not??? All the experts on here can rubbish this notion, I don't care. Makes perfect sense to me, that's all that matters.
Tom Walker asked about a better brand of adj lifter; in my opinion, Flatattack [Mike Davidson] in Australia has the ultimate style. Do a Google search.
In my opinion, time spent doing the best valve job possible on a flathead pays off immeasurably in the total engine performance.

[Brian]

This thread is getting a bit off topic but here goes; my method of adjusting valves is the method described by the great rumbleseat;

VALVE ADJUSTING WHILE THE ENGINE’S ON AN ENGINE STAND: This is when I
prefer to set the valves since I can better see what’s going on. There
are two methods I use to adjust the valves during engine re-building.

(1)Degreeing the valves

(not the cam). Degreeing the cam using a single exhaust
and intake lobe assumes each lobe is EXACTLY the same. I don’t find this to be
true in very many cases. Degreeing the valves is by far the most accurate in my
opinion. This is done on the engine stand after valves, cam, crank and #1 piston
is installed. BTDC is Before Top Dead Center and TDC is Top Dead Center and CW
is ClockWise and CCW is CounterClockWise. Bring up #1 piston to exactly TDC.
Make and install a pointer near the crankshaft pulley. Install a degree wheel on
the crank pulley. Index the degree wheel so the pointer is exactly pointing at 0
degrees and secure the degree wheel to the crank pulley (a couple of strip
magnets work). Be careful to not disturb the degree wheel or pointer from this
point on.
Example: Let’s assume a particular cam’s spec for an intake valve to begin
opening is 20 degree BTDC. Back off the crank shaft CCW about 30 degrees (BTDC)
or so using the crankshaft nut and a long breaker bar. You want to be able to
rotate the crankshaft easily and smoothly, so use a long bar or a cheater pipe.
Install a dial indicator on #1 piston’s intake valve. Turn the crank CW (always
turn the crank CW (facing the front of the engine) when setting and checking
valve clearances) until the degree pointer is 20 degrees BTDC on the degree
wheel. This is when the valve should barely begin lifting off its seat. Adjust
the adjustable lifter until the valve moves the dial indicator’s needle less than
a thousandth of an inch. Time to check it. Turn the crank CCW several degrees
before 20 degrees. Now turn the crank very slowly CW while watching the dial
indicator closely. The needle should just barely twitch when the 20 degree BTDC
mark on the degree wheel lines up with the pointer. If it doesn’t, re-adjust the
lifter and check again. When satisfied, back off (CCW) the crankshaft until you
reach the spot where the lifter to valve clearance is the greatest. This is
determined by trying various thicknesses of feeler gauges while rocking the crank
back and forth several degrees. All that’s left is to measure the clearance
between the valve and lifter using a feeler gauge. This is #1 Intake valve’s
clearance. Record it for future use as #1 Intake for your records. That valve
is done. Now do all the valves. Don’t forget to record their clearances as you
go..... for your records. After the first couple of valves, it goes pretty fast.
I degree valves in a flathead in a few hours after the initial set up.
A real benefit is in the future I need only to re-set the clearances of each
valve to the clearances recorded and the valve is degreed. How? I turn the
crank so the lifter is the farthest from the valve. Let’s assume a particular
valve was degreed at 0.011" clearance. Since valve clearance normally increases,
we can use a feeler gauge thicker than 0.011" to determine where the lifter is
furthest from the valve. Use the thickest feeler gauge that’ll slide in between
the lifter and valve. Say it’s 0.014". With the 0.014" feeler gauge between the
lifter and valve, rotate the crank back and forth several degrees until you find
the spot the feeler gauge is the loosest. Now adjust this to 0.011" clearance
and it’s exactly the same as if you just degreed it! Neat... neat! Degreeing

valves always results in an increase in horsepower.

[john mullen]

^^^^ now that's info we can all learn from...Great post Brian.....