Should I pull the motor?

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Joined
Feb 14, 2016
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Clover
My Car
72 Mach 1, Q code 351CJ, 4 speed.
According to the PO the motor was rebuilt about 4 years ago and then parked after that. Inspecting it from underneath it looks like it has been out before by the absence of road grime.

I know I have a problem with the driver side head gasket either blown or not torqued correctly. I have not had time to investigate much but pretty sure the head will have to come off. While off I am going to open up the exhaust ports and smooth out the runners a little then take them in for valve job, screw in studs, hardened seats, springs and retainers matched to whatever cam I choose.

Here is my dilemma, the oil is clean, there's no hard particles under the valve cover or in the oil, pressure is good, no knocking, and with the exception of fouling plugs on the back 2 driver side cylinders the motor runs fine. I am planning on a fairly large flat tappet solid cam but have no intention of drag racing or prolonged high RPM's Just going for sound, cruising, tire smoke and push you in the seat torque.

Is there a need to pull the motor?????

Thanks

Wade

 
No it is not "needed" to do what you want to do. But if you want to clean up the engine compartment and paint and clean the motor and make it all nice and pretty under there, now would definitely be the time to pull the motor. Makes it a lot easier to change heads and cam swap on a motor stand rather than bent over a fender. But you can do it in the car. Its really up to your personal preference. If it was me, I would pull the motor and detail everything up nicely.

 
I find pulling the radiator, motor and transmission to be a relatively easy job. Start to finish it should not take over two hours.

Installation takes a bit longer but still isn't really that bad.

Since you will be pulling the heads anyway, you won't even need anything in the way of additional new gaskets, so it seems to me to be worthwhile.

 
Just curious why you're staying with a flat tappet cam, knowing about potential oiling/break-in problems?

I agree, either in the car or on an engine stand. I agree with Kevin and Jeff, I would do it on an engine stand, and replace the cam bearings with the T Meyer restrictor bearings.

 
I don't think there is any problems with my engine BUT i want to strip it out and check the guts then replace whatever needs to be done and paint the block before it slots back in. It makes sense to me knowing its done 93000 miles before i owned the car and unsure if it has been worked on before i had it. After 40+ years i feel sure its time and money well spent.

In your case you don't know how good a job was performed on the engine by previous owners. Peace of mind is priceless IMO

 
I don't think there is any problems with my engine BUT i want to strip it out and check the guts then replace whatever needs to be done and paint the block before it slots back in. It makes sense to me knowing its done 93000 miles before i owned the car and unsure if it has been worked on before i had it. After 40+ years i feel sure its time and money well spent.

In your case you don't know how good a job was performed on the engine by previous owners. Peace of mind is priceless IMO
That's an excellent point. When I first got mine it was fairly low mileage and I pulled the heads to have hardened seats installed and the valves replaced. It still has the factory hone marks in the cylinder walls, runs very well, good oil pressure, great compression, but I keep thinking the same thing, be nice to replace the 45 year-old moving components. If I do I'll likely stroke it at that time.

 
If I was doing both the heads and cam I would pull the engine. You have everything off to yank the heads. Heck, you might be able to leave the exhaust manifolds on.

So it's just a matter of unbolting it from the transmission, engine mounts and Pulling the hood.

 
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Two things that my Dad taught me years ago:

A) Don't fix what ain't broke.

B) Be sure you know where to "pinch the burning fuse" when it comes to "fixing up" an engine. It usually involves a SOLID game plan.

So, if the engine... assuming it is a lower compression stock type rebuild... is fresh, it most likely will have a sub-10:1 compression ratio. Most likely, any solid flat tappet grind that has a rumpity engine note will make for a dog in the performance department.

Be careful, choose the cam as a package... every engine component will affect the outcome.

Back in the day, my high school Torino had a cool sounding lumpity hydro Crane cam, single plane Offenhouser with a 750 Holley on an otherwise stock 9:1 compression '69 351W and a stock FMX... only ran 15.40's with 4.11 gears. I had to force it to spin the rears. It was depressing and somewhat embarrassing. That was before I knew what component selection and intended use was all about.

Yes, engine building is a loooong drawn out process with absolutely no black and white correct answers. Choose wisely.

 
I know from your previous posts that you want a thumper. If you do that for a street engine or even race it will not last long. High lift cam and idle do not go hand in hand. It does not matter what break in you use or oil if you let a high lift cam sit and idle it will eat up the cam and lifters. The lobes on the cam get oiling from oil slinging off the crank and some coming from the lifter bores. Even when ran at speed they do not last long. High compression will give you a thump also and not beat the cam to death. But has it's issues also with available fuel.

Like has been stated pulling an engine is a few hours. Hey they had to put the them in in less than 2 minutes on the line.

Pull the engine practice makes perfect.

 
I would want to know that the bottom end of the engine was in order anyway, more so if you are going to rebuild the top end with an eye toward increasing power. Easier to do that with the engine on a stand.

 
Pull the motor. It's not that hard as long as you do the right prep and get the right size hoist. 2 T minimum or you likely won't have enough reach without stripping the entire front end down. Ask me how I know!!! An engine leveler is a good idea too.

While you're in there, do the engine bay completely. Oh and why not tidy up the wiring, etc. etc. Details details. While not anywhere near concours, not my thing, there is a post on engine bay detailing and materials used that might interest you. You'll be amazed on the great comments you'll get if you show it.

 
If you are considering a power upgrade would it be worth your while just replacing with a crate engine of your choice?

When you take into account the man hours plus parts to upgrade the old engine and set that cost against a crate engine of your choice(I would opt for a crate Boss) which should slot right in you may want to opt for a crate.

Personally if i were in your shoes and going down the same road i would go for a modern crate with much much more power. I am going concourse so only one road for me to travel

 
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