First time flathead cam removal

R

RandyMettler

Senior Member
I am planning on removing a camshaft from a 8BA. Never done this before. Can you remove the camshaft when the engine is mounted to the frame? Do you have to pull the crankshaft first? I understand the valves have to come out and the timing cover needs to come off, but is it that simple or do you have to drop the oil pan and yank the back bone out of the beast. I understand coaxing the cam back into the block is a delicate procedure and you need one hand outside the block and one hand inside to keep from damaging things. Also I have two, what I am going to call retaining plates in the lifter valley that I have no idea how they are attached or how to remove them. There is a smooth shaft that runs through them the full length of the block? The you tube videos on this show the total rebuilds fragmented, I just need to identify the cam for lash settings. It might be a full race cam, but I am not sure. It idles in patterns for short durations. Constantly shifting it rhythm. Lopey. To me that is a race cam, but this is speculation. The existing lash at intake valves measured was between 0.17 and .020. The previous owner may have incorrectly set the lash according to 8BA settings, which would have been specified at around .018. The cam is from a 59Aera engine in a 8BA block so the intake lash at intake should have been set around 0.12. I really need to see what's going on internally. I was told it was a recent rebuilt and I tested the compression and measures 110 on all cylinders so I would be surprised if the cam was old and tired, but again not sure. They may have not addressed the cam or done a rebuild and just replaced the rings.

Do or do not, there is no try!
I prefer running head first, bashing my way through obstacles, yah it hurts, and there are complications along the way, but in the end at least you know where you stand.
A wise man sees a problem and fixes the issue no matter what the cost, an ignorant man sees a problem and simply turns away. Who becomes richer in the end?
 
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The items in the valley on the smooth shaft are oil baffles. they just clip around the "shaft" and can be pulled off easily. the "smooth shaft" in the valley is the oil pipe and should be left undisturbed.

Remove the valves, remove the fuel pump housing and pushrod, remove the lifters (store them in order if intending to reuse them.

The crank can remain in place.

Withdraw the cam.

When refitting, it would be better to have all round access, but you might get it in ok if you have the engine tilted up vertically. Similar for removal.

There's nothing trick or different, it should be a straightforward job.

Mart.
 
If you are going to reuse the valves and lifters keep them in sets and number them so they can go back into the same spots.
Your going to love how easy these old flattys are to work on. Chap
 
The first thing you need to do is collect the right tools to remove and replace the valves, guides and keepers.
 
If you just want to know "what" cam it is there may be markings on the end, possibly under the gear, but most likely you need the cam in the engine to use a dial indicator and degree wheel to plot the cam -----several cams I have are obviously not stock, even a brand new one, only one has any markings that give some ides, and it only says "3/4 race"(stamped on the gear mounting flange), and would have to be put in a block and tested with dial indicator and degree wheel to really know ----
 
If you change cams make sure the bearing journals on the new cam is the same size as the old one. Sometimes those journals gets reground to .010 undersize. If that happens you will have little or no oil pressure unless you change the bearings also.
 
As Kurt in NJ said, to identify the lift and duration of the cam you need to measure the lift and duration of the cam. This is best done with the cam, crank, rods, and pistons in the engine. You will need a positive piston stop to establish TDC, a dial indicator that has a range of at least. .500, I have a dial indicator with a 1 inch range and I suggest you do the same. I recommend a quality dial indicator like Starrret or Mitutoyo, either will last you for the rest of your life and some sort of magnetic base to position the dial indicator, and a degree wheel. Google how to degree a camshaft, lots of info. You will want to degree both the intake and exhaust of at least one cylinder, usually number 1. No need to pull the cam, but the heads, and intake manifold need to come off. The front cover can stay on but it sounds like you have it off already.

Have fun. Mike.
 
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Thanks for the help. The reasoning for wanting to remove the cam was to identify it. I did not know it could be degreed in place. From there I will be able to find out if it is a stock 59A cam or not and go from there with the setting lash gaps. That is definitely the way I will approach the problem.

Regards, Randy
 
If your just replacing the cam with a stock one , forget the BS about degreeing in the cam. I've changed many cams while in the car, however if you've never doe it before, make sure you have ALL the right tools includong the special valve removing and replacing tools. also two 5/16 NF bolts 6" long to guide the cam back in. I've done this on the stock car in less than 2 hrs with help. Expect to spend a few days.
Good luck??
Ol Ron
 
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