Classic/Antique Car Repair: valve adjustment on flathead Packard 288 engine, valve lifter, thin panel

Question
I would like to know if it possible and feasable to adjust the valve/tappet clearances with the engine running. I heard about this but have never seen it happen. My 8-cylinder Packard 288 is very difficult to turn round. I cannot reach the central nut of the torsion damper because the radiator is in the way.
Gerben Wassenaar

Answer
Yes, it is possible to adjust the valves with the engine running.  
That is the best way to do it because the engine must be at full operating temperature to get a correct adjustment.

The way to do it is to place the front of the car on strong supports (jackstands).  

Then remove the right front wheel.



Turn the steering wheel all the way toward the left.

Place a comfortable padded box to sit on just behind the right front brake drum.

Then remove the thin panel of steel which hides the engine from view from a person sitting under the right front fender.  

Place a work light along the right side of the engine, facing the engine (and not facing your eyes).

Then remove the 4 long bolts which hold the valve lifter covers in place, and remove the covers.

Now start the engine and wait for it to become completely warm to  normal operating temperature.  

Then adjust the idle speed as slow as the engine can tolerate without stopping.   

Then with two 1/2 inch wrenches, loosen one valve lifter at a time, and adjust the valves to the specified clearance.   

Adjust the exhaust valves to between 0.010" and 0.012".
Adjust the intake valves to between 0.007" and 0.009".

The rearmost valve is very hard to access unless you first remove the heater on some year Packards.  You did not tell me what year or model your car is, so I can't advise you further on this problem.  You can try to adjust the rearmost valve with the heater in place - you may be able to do it, depending on what tools you are using.

This is a hot, dirty job, as you will be working under a dirty fender, and bumping up against a very hot exhaust pipe.  You will get oil all over your tools, and dirt in your hair.  But when you are done, your engine will be very quiet, and it will stay quiet for at least 20,000 miles.

As you may have learned from reading my introduction materials, before I retired in 1994, I was the proprietor of a Packard repair garage for many years.  I've done this job on many, many Packards - so if you have any problem at all with what I have written, please tell me with a "follow up" question and I will try to help you further.

Good luck with your car!

Dick Benjamin