CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES
462624.....75-86...350/400......76cc chamber, 1.72/1.5, 1.94/1.5 or 2.02/1.6 valves
FOUND my 400sbc
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CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES
462624.....75-86...350/400......76cc chamber, 1.72/1.5, 1.94/1.5 or 2.02/1.6 valves
Not really. They aren't smog heads.
Once the heads are off you can check the bores visually and for cylinder leakage past the rings. You can check the valve to seat seal as well with a gallon of diesel fuel very easily. I wouldn't consider bolting this in without dropping the pan and pulling the heads.
As Shawn mentioned, if they need to go to the machine shop then they need to go - it has nothing to do with whether you pull them now or later. It's way better to do it now rather than after the motor is in the car. It's so easy to put in ne gaskets and forget about it if everything checks out OK imho.
Since it’s at the shop have it hot tanked, they can pressure test it, magnaflux it. Once you’re at that point if it passes, it’ll need new cam bearings and all plugs. After that you’ll need to decide what to do. They can check the bores and possibly get away with a hone. If not they can go to .030. I seem to remember you saying it was .020. You can decide if you want them to take a cleanup cut on the decks and resize the mains.
It’s not at the shop yet. I guess when I get more cash I’ll be taking it up there
For a 400, those head numbers would about equal "boat".
What concerns me more is Pic #1 that shows the exposed valves with no rockers and all that surface rust. To me that say that that motor has not seen oil in its galleries for a fairly long time. If that rust was not present to change my mind, and with Pic 3 showing no Distributor present so what I would have suggested is that you drain the oil pan and change the filter, and then refill the pan. Then get yourself a oil pump drive adapter that fits into the boss for the dizzy, and can be attached to a HD 1/2 drive drill motor. There ware various versions but the one to get is the type that has an outer body that replicates the lower housing of the dizzy. This is because the cross feed from side to side goes through the opening for the dizzy housing and that casting has a channel cut into it to direct the oil from the one side to the the other. Put a cheap oil pressure gauge on the motor and Use the drill to spin the pump until you start to see oil coming up into the lifters. It would be simpler if the pushrods and rockers were still mounted as top end oil comes up the pushrods and cascades down from them over the rockers. Without them you will need a flash light to peek down the pushrod pockets to see what the lifters are doing. Why all this???
To Pre Oil the bottom end, mains and rods, as well as the cam journals. Once you see oil in the cam valley, gently rotate the crank about an 18th of turn and repeat the pre oiling process. Do this for one full turn of the crank, aka 360 degrees. Why, again? Because the the various oill passages and galleries only get oil when they line up with each other and that only occurs at certain points in the rotation cycle. You want all the journals and bearing shells to get as much oil as possible before you go any further.
Unfortunately, seeing that surface rust basically says to me that the only option here is to pull the heads and the intake and take a look at the piston tops and the cam lobes. Going back to my decision tree from earlier. This engine, to me, is a core. Rust, no matter how minimal, suggests neglect. Better to just bite the bullet and tear it down.
As for the thought that the heads could just be pulled, sent to a machine shop and cleaned, the valves ground ad reseated, and then re-installed, What that gives you is new heads and an old bottom end. So be prepared for blowby and oil consumption because the rings and bearings are now older and more worn than the heads so possessed of greater tolerances due to wear that will allow oil to get to places it has no business being.
Nick
What concerns me more is Pic #1 that shows the exposed valves with no rockers and all that surface rust. To me that say that that motor has not seen oil in its galleries for a fairly long time. If that rust was not present to change my mind, and with Pic 3 showing no Distributor present so what I would have suggested is that you drain the oil pan and change the filter, and then refill the pan. Then get yourself a oil pump drive adapter that fits into the boss for the dizzy, and can be attached to a HD 1/2 drive drill motor. There ware various versions but the one to get is the type that has an outer body that replicates the lower housing of the dizzy. This is because the cross feed from side to side goes through the opening for the dizzy housing and that casting has a channel cut into it to direct the oil from the one side to the the other. Put a cheap oil pressure gauge on the motor and Use the drill to spin the pump until you start to see oil coming up into the lifters. It would be simpler if the pushrods and rockers were still mounted as top end oil comes up the pushrods and cascades down from them over the rockers. Without them you will need a flash light to peek down the pushrod pockets to see what the lifters are doing. Why all this???
To Pre Oil the bottom end, mains and rods, as well as the cam journals. Once you see oil in the cam valley, gently rotate the crank about an 18th of turn and repeat the pre oiling process. Do this for one full turn of the crank, aka 360 degrees. Why, again? Because the the various oill passages and galleries only get oil when they line up with each other and that only occurs at certain points in the rotation cycle. You want all the journals and bearing shells to get as much oil as possible before you go any further.
Unfortunately, seeing that surface rust basically says to me that the only option here is to pull the heads and the intake and take a look at the piston tops and the cam lobes. Going back to my decision tree from earlier. This engine, to me, is a core. Rust, no matter how minimal, suggests neglect. Better to just bite the bullet and tear it down.
As for the thought that the heads could just be pulled, sent to a machine shop and cleaned, the valves ground ad reseated, and then re-installed, What that gives you is new heads and an old bottom end. So be prepared for blowby and oil consumption because the rings and bearings are now older and more worn than the heads so possessed of greater tolerances due to wear that will allow oil to get to places it has no business being.
Nick
Hey nick thanks for that detailed reply! I already took the heads off, but I do think I have one of those oil “prep sticks” I used it on my 350 a while back. I’m in the process of pulling out the lifters, a few are stuck. I can tell the motor hasn’t been moved in for ever
IMO: Don't waste a dime on it. A "400" couldn't get out of it's own way when new! You are going to use up money in machine shop, and a bunch on parts better used on a 327/350.
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