Camshaft replacement

[ChrisH]

After removing the very dented oil pan I shined light and looked over the bottom end of the engine and was pretty happy with how things looked until I looked up at a few of the visible camshaft lobes.  Looks like pieces are breaking off at least one lobe and another looks porous.  I don’t feel the engine needs to come completely apart or rebuilt but a cam change is a must. Im interested in people’s opin

 

[delawarebill]

ouch!!! that puppy needs a new home.. trash can. what motor do u have?

 

[ChrisH]

ouch!!! that puppy needs a new home.. trash can. what motor do u have?

It is a 1973 Q code 351

 

[Carolina_Mountain_Mustangs]

If the engine has never been out and serviced you should probably just pull it and do complete rebuild. The core plugs in the block rust out and will leak also.

I see your bushings on your upper shock mounts are gone. If you jack the front end up or use a 2 post lift you need to block the upper control arms so they do not drop down and pinch the rubber washers into. Can also split the radius rod bushings.

If the cam looks that bad I am sure bearings are worn and might need crank ground. If there is a ridge in the block rings can hit and crack a piston also. Jobs like this do snowball.

 

[Hemikiller]

Not knowing what your plans are for the car, if it runs fine, I'd leave it as is.

If it's really bothering you, replace it with a modern version of the factory CJ cam that is ground straight up, not retarded like the factory unit. You'll also want to put in a good double roller timing chain like a Cloyes.

 

[Don C]

If you're looking for an excuse to improve performance, this will be it. Just be forewarned that you'll likely wind up rebuilding the engine. Just remove the engine to start with. At a minimum you should replace the cam bearings and the engine needs to be out for that.

And, while you have it out now will be a good time to have the heads gone through and have hardened valve seats installed. Check the wear on the valve guides, will likely need to be replaced or knurled. And while you're there have them machine the guides for positive seals. And while you're having that done may as well get them machined for adjustable rocker arms. Check the valves and valve springs. If you're going with a performance camshaft you'll need new springs anyway. And, now is a good time to replace those original two piece multi-groove valves with single groove one piece stainless steel valves.

Now that you've got the heads off and the engine out it's easy to pull the pistons out, check the piston wear and cylinder wall wear, check the rods and replace the rod and main bearings, check crankshaft wear.

See how it will escalate?

Edit: And then when you need to have it bored and the crankshaft needs to be ground, may as well as stroke it, and you just started out to put in a cam

 

[Hemikiller]

If you're looking for an excuse to improve performance, this will be it. Just be forewarned that you'll likely wind up rebuilding the engine. Just remove the engine to start with. At a minimum you should replace the cam bearings and the engine needs to be out for that.

And, while you have it out now will be a good time to have the heads gone through and have hardened valve seats installed. Check the wear on the valve guides, will likely need to be replaced or knurled. And while you're there have them machine the guides for positive seals. And while you're having that done may as well get them machined for adjustable rocker arms. Check the valves and valve springs. If you're going with a performance camshaft you'll need new springs anyway. And, now is a good time to replace those original two piece multi-groove valves with single groove one piece stainless steel valves.

Now that you've got the heads off and the engine out it's easy to pull the pistons out, check the piston wear and cylinder wall wear, check the rods and replace the rod and main bearings, check crankshaft wear.

See how it will escalate?

Don, you just caught a case of the "while I'm at its" ....   lollerz

 

[Don C]

Just ask me how I know...

 

[midlife]

You missed a few, Don...You need to strengthen the shock towers to support the motor mounts for the more rugged engine, beef up the transmission and rear end, add subframe connectors, new gas lines and new brakes and lines. I'm sure there's something while he's at it that will entail a re-paint of the car...

 

[Spike Morelli]

Your camshaft has served a long and successful life, but is showing all of the miles. I agree with all the above that an overhaul of the entire engine is prudent, but if it's running pretty good right now, and you have the time.....you can soften the overall cost of doing it all at once by accumulating some of the parts needed now, before you decide to tear it down. Certainly the clean-up bore size can't be known until it's apart, or bearing oversizes, but a full gasket set, a new cam, lifters, timing components, cam bearings, oil pump and drive, etc, can be purchased bit by bit now. The good news is there's nothing like a fresh engine! Something to look forward to, not fear.

Pull a rod and a main cap off while you're down there and check for signs of wear. Just further indications of engine condition. One more thing....for safety's sake, move the fuel filter from right above the coil and distributor to a location not so likely to start a fire if it leaks. Just sayin'....

 

[ChrisH]

I appreciate everyone’s input.  I was already planning to build another engine and set the original aside.  I am going to put the oil pan on and make it so it can at least move under its own power until that happens.  I just won’t drive it this fall like I had wanted.  Thanks again

 

[Carolina_Mountain_Mustangs]

If you do not have any knocking like a bearing going just drive it. A worn out cam just affects performance.

It is my opinion that some of the suggestions are the snow ball I was referring to. Your engine looks to probably be original so it stayed together for over 35 years. The two piece valves do not break because they are two piece. They break because someone does not know how to drive. Over reved the engine floated the valves, bent the head on the valve when it hit a piston, then it flexes back and forth until it breaks just like bending a piece of wire does. You do not need hardened seats or Stainless valves. Why would you? I have a 1956 Ford that only had Pure White gas used in it. That was the first lead free gas made and was back in the 50's. We use to burn it in our Coleman camping stove. That car has over 90,000 miles on it without hardened seats. Heads never off the car.

Put your oil pan on and drive the car with common sense. It will not wind 7,000 rpm and I would not wind a new engine to that. No reason to. Build your engine for torque not high rpm and it will last forever. When you do the rebuild put a rev limiter on to make sure you do not float the valves. You cannot take it back once you do.

Oh BTW we use to tulip the valves before you could go by every form of part know to man. We put in lathe and turned at least .030" to .060" from the back side and smoothed out the radius. Those valves did not break even after cutting. You can blow any engine made in probably less than a minute if it does not have rev limiter. The net affect of cutting the back side is increasing valve lift by what you cut off the back side of the valve. It also lightens the valves and so not as tough on the valve springs.

So go to a show this weekend and enjoy the fall weather in your Mustang.

Great idea to do another engine. If you are not going to race forget the racing parts they do not last.