Is the correct assemble sequence for the valve train in an 8 with hydraulic tappets
I put the valves in before the tappets and blocks, it is a pain compressing the valves and getting the keepers in, harder if the tappets are in the way. The cam can be rotated to a no lift position for all 4 valves of each block. The blocks with tappets can be removed with the engine assembled, but a bit tricky to keep the followers from dropping out as you do it. I am already forgetting, but I think when assembling the blocks I angled the blocks in so the cam would keep them from falling out, then the tappet plungers could be depressed enough to roll the blocks into position. You might have to pull them in and out again if the allowed tappet clearance isn’t within spec – it is a very wide allowance though since they are hydraulic.
Thanks Jim. That is just what I was looking for and makes sense.
Jim is correct: Install the valves and springs, then the lifter blocks. It is important to have the lifters themselves dry inside. When the lifters have oil in them, you cannot compress them and you won’t get them between the cam lobes and the ends of the valve stems.
In the early Motors Manuals, there is about a page of info about the Hydraulic lifters and procedures. They suggest using gasoline to clean the lifters of oil and dirt [hopefully not much dirt!] and installing the lifters dry.
Bill it is also very important to make sure the gasket between the lifter block and the engine block is positioned correctly and not blocking the oil ports. The gaskets have too small of holes for the oil ports, and as such if the gasket is just a bit off location, the oil ports can be blocked..
I forgot to add: Make sure that you have some gap between the lifter plunger and the end of the valve stem.. Depending on your valves and how deep the seats in the block have been cut or ground it is possible to have no clearance when the lifter plunger is fully depressed and the cam lobe is down.. this would be a very extreme example of a valve overly ground and the seat very deeply cut into the cylinder block but it is possible..
Thanks Jim and Greg,
Happy New Year, by the way.
I bought an industrial ultrasonic cleaner and plan to use it on the tappet bodies.
Working on getting the rust/gunk out of all the oil passages.
I have 3 cam bearings in and am going to grind the valves next.
Hoping 2021 has less obstacles on all fronts.
Ultrasonic cleaner arrived today. Plugged it in and nothing happened. Hummm.
Took a panel off and found an unattached wire, plugged it in and off it went.
It is a 6 gallon and works with a variety of solvents. I am using Simple Green Concentrate I got at Home Depot. Makes about 13 gallons I think and is biodegradable. The solution gets dirty in a hurry. I got it basically to clean delicate parts but I think I will use it instead of my parts washer to clean greasy/oily parts. If you are trying to do rust removal you would need a different solution.
Seems well made for a Wuhan product. It has a digital heater and timer. Came with a basket and lid. 300 series Stainless it appears.
I put the cam retainer flange, which was very greasy, in for 10 min. Here is before
And here is the after. Probably could have left it in for longer. It does a great job of cleaning in threaded holes and bores. Might throw the tappets in later today. Even cleans around the casting numbers.
Here is a tappet block before. I punch marked the body (#4) and the rim of each tappet so I could keep them in their original bores.
And after 30 min in the UC. Need more disassembly and time in the tank I guess. The oily looking areas on the bracket is just water. They are squeaky clean. Should have bought one of these when I got the car.
On the Ultrasonic cleaner, I have found out that it is important to rinse and dry the steel parts ASAP and I use a fogging oil on them.
They are so clean, they tend to get surface rust very quickly.
Back to the cam bearings.
I made this tool on my lathe out of aluminum. The cam bearings get progressively smaller, so I started with the front hole in the empty block and machined the drift to fit the bare hole with a shoulder at the top. Then I measured the id of the bearing and made a step so the drift just fit the id of the bearing, had a shoulder to sit on the rim of the bearing but would clear the block as the bearing was pushed out.
I center drilled it so I could use an all thread rod to pull it in, just in case I had problems driving them in.
Once out I inspected degreased and ultrasonically cleaned the shell. They are numbered and are of the split ring type and were in great shape.
I used the same tool to reinsert them in the new block. Once one was in I repeated the measure and machining process to fit the next (smaller) hole.
5 down and 1 to go but I have to flip the block to get at the rear bearing and plug. Since the cam is thru drilled, bearings 2 thru 5 have no oil holes so there are no alignment issues.