CK5
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71K5 - BP71K5's Just for fun build

That's good to hear. I backed off on a few more of my "might as well" upgrades and had to double down on some others. So I can use the extra encouragement that this thing isn't going to be a dog.

I was waiting on parts to put it back together. Then I ruined the cam bearings removing the cam so I'm waiting on tool to replace the cam bearings. Doing everything I can to resist the urge to remove the crank and pistons.
I avoided doing a lot of work on mine because I knew it was a good running motor with low miles. Don't know if you have that advantage or not. I always have this philosophy that I don't mess with stuff that's working fine if I can absolutely help it.

I was thinking yesterday, "Wow! This truck is fun to drive!" I guess I just hadn't appreciated how doggy the other motor was. Plus it blowing oil smoke everywhere on startup. I need to replace my rear seats with a bench seat so my dog has a more comfortable spot to ride so then I can drive it to work more often. He likes to lay down but he's too big to lay in a bucket seat.
 
At least a timing chain as well...cough cough!

You can cheat on the head gasket a little to get compression up if your gonna leave the stock pistons in it. The standard deck clearance is .025 and most common head gasket is .039. So with that setup your looking around 7.90-7.95:1 w/ the big open chamber 119cc heads. Or find a cheap set of closed chamber around 105-110cc chamber. That would get you in the ballpark of 8.45-8.75:1 Also when ya take the timing cover off pop the 2 oil galley plugs out and drill them to .03, it'll help w/ oiling of the timing chain and also help w/ air lock @ start up....

So you still thinking the Comp Cam 11-235-3 cam?

Timing chain is way past done.
I avoided doing a lot of work on mine because I knew it was a good running motor with low miles. Don't know if you have that advantage or not. I always have this philosophy that I don't mess with stuff that's working fine if I can absolutely help it.

I was thinking yesterday, "Wow! This truck is fun to drive!" I guess I just hadn't appreciated how doggy the other motor was. Plus it blowing oil smoke everywhere on startup. I need to replace my rear seats with a bench seat so my dog has a more comfortable spot to ride so then I can drive it to work more often. He likes to lay down but he's too big to lay in a bucket seat.

The only thing left in the block is the crank and pistons. I'm still flip-flopping on tearing it the rest of the way down to clean all the oil passages. It looks like a pretty clean engine, it just goes against every instinct I have NOT to clean it the rest of the way, but I'm aware of the slippery slope that will happen.
 
Timing chain is way past done.


The only thing left in the block is the crank and pistons. I'm still flip-flopping on tearing it the rest of the way down to clean all the oil passages. It looks like a pretty clean engine, it just goes against every instinct I have NOT to clean it the rest of the way, but I'm aware of the slippery slope that will happen.

Don't forget to drill the front oil galley plugs behind the timing chain when you go to reinstall the new timing chain! :waytogo: The Newer BBC's are like that now from the factory, but a .030 hole is spec on them.
 
One more order from summit to do. Any opinions on head gaskets types to avoid or get? The MLS gaskets seem to be good and kind of looks like what the old one was that I removed. Care more about sealing performance than cost.
 
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Update 05/27/2017

Turns out you can't replace the cam bearings while the crank is in. So here we go...

Cam bearing tool made the bearings super easy to remove. dont see any signs of serious trouble so I'm hopeful to get away with just a block cleaning.

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Only part that gave me trouble is this plug behind the cam gear hole. My allen head driver stripped it. Incidentally, the plugs are already drilled with a small oiling hole. I think an extracted bit can get it out.
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Update 05/27/2017

Turns out you can't replace the cam bearings while the crank is in. So here we go...

Cam bearing tool made the bearings super easy to remove. dont see any signs of serious trouble so I'm hopeful to get away with just a block cleaning.

Only part that gave me trouble is this plug behind the cam gear hole. My allen head driver stripped it. Incidentally, the plugs are already drilled with a small oiling hole. I think an extracted bit can get it out.

It's been apart before then, might even have an aftermarket cam already in it.....
 
Heat the plug with a torch. Then quench just the plug with water. Should make it come out easy.
 
Beat a torx socket in the plug, usually works better than an extractor.

Did try that, torx just stripped the recess out.

Heat the plug with a torch. Then quench just the plug with water. Should make it come out easy.

Tried that too. It laughed at me. So used a big extractor and that snapped it loose.

I did notice a very light scratch in the #8 cylinder bore that I don't remember seeing before. It's just a glaze difference and not something you can feel. So I checked the #8 piston and found the oil ring had an end that was sticking up. Turns out one end had slipped under the edge of the other and so it was sticking up a bit. Maybe happened when I was removing the pistons. You can see the thin metal end sticking up a bit here.
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I was able to pop it back in place, but I found a few rings were pitted as well so I ordered a new set of rings. Now I gotta figure out where to get a bore brush to prep the cylinder bores for the new rings. Then measure everything to make sure it's still in spec and then final cleaning and reassembly.

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Update 6/02/2017:

Well bringing the block to a machine shop and having them clean it, install cam bearings, and prep the bores might've been a little cheaper but I've successfully installed the cam bearings, clean the block, and got what looks like good crosshatch on the bores and I'm already for assembly.
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Cam bearing install tool.
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A little tricky getting those in since the tool can gouge them if it's not sitting right. One got a little burr on the edge but I was able to remove it with an x-acto knife.

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Even test fit the new cam and it spins freely. So I think I'm ready to assemble when I get back from some business travel in the next couple weeks.
 
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My correct size piston ring compressor is stuck until the 5th coming from Ohio so I'm only able to get the crank installed tonight. Bearing caps are torqued to 95 ft/lbs and crankshaft end play is measuring right at .005" which my book says is in the correct range. Also got all the coolant and oil galley plugs installed with teflon tape. Pistons and rods are all cleaned up ready to go.

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I also thought my cash outlay was about done but forgot I will need a new flywheel and clutch parts. :doah:Decided I'm going to keep the TBI system for a while at least until the motor is broken in and get some summer fun in. That's puts a lid on the cash flow as well. Just not sure if I should get a bigger throttle body or just try and run the one I have.
 
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That puts a lid on the cash flow as well.

Just measured my clearance from bellhousing to radiator and I'm easily 2" short (motor is too long). That's not going to be cheap to fix, especially given my rear driveshaft does not want to get any shorter. I see ORD's magnum box is a bit shorter than the doubler setup I have now. Any other options?
 
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Just measured my clearance from bellhousing to radiator and I'm easily 2" short (motor is too long). That's not going to be cheap to fix, especially given my rear driveshaft does not want to get any shorter. I see ORD's magnum box is a bit shorter than the doubler setup I have now. Any other options?

The big block should have sufficient fan/radiator clearance if the engine is still in the original 4wd position even with a long water pump.:dunno: A stock 2wd fan shroud should work.

You will want a 454 size throttle body if you want any performance at all.

You can reuse your 350 flywheel and clutch with this: https://www.summitracing.com/parts/fiz-624541/overview/
 
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