1972 402 - advice

[69Tom]

So, I recently picked up a running 72 402 engine. Compression is good.

As it's sitting on an engine stand at the moment, before putting it in my truck, what advice do you have? I plan on scraping the oil off of it, power washing and repainting.

I was thinking of replacing head gaskets, but since the pressure is good, should I leave them be?

Replace main seal?

Change out cam?

Want to keep the costs down, as I'm fairly broke after the purchase and still have to buy brackets and pulleys.

Your advice is appreciated. I know what do to when I'm completely tearing the engine apart, but I'm new to relatively leaving one be for the most part.

Thanks!

[truckster]

I would replace all seals and gaskets except the head gaskets.

If that's too much money, I'd do the ones that will be hardest to get to once it's in the truck: rear main, oil pan, timing cover. The intake and valve cover gaskets can be done with it in the truck, if that becomes necessary.

If it runs well and you're on a budget, I'd leave the cam alone. If you're unlucky breaking in a flat tappet cam you'll be rebuilding the engine.

[69Tom]

I should be able to cover costs for the gaskets and seals. As you said, once it's in the truck it's a pain to get to several of them.

Any recommendations on what brand seals or where to get them? I assume a kit is available.

[truckster]

I've always had good luck with Fel-Pro.

[sweetk30]

its a good running 402 BBC clean it up and run it . maybe a good double row roller timming chain and maybe a small intake manifold . otherwise its a touqe monster like all big blocks are . .

[jjzepplin]

Timing chain , oil pump, freeze plugs, water pump and run her.

[GASoline71]

Probably just me... but... I've never purchased a used engine with the intention of bolting it in and driving a rig. A used engine to me is a rebuild...

But if I were to attempt to use it, I'd pull the pan and at least pull off a couple mains and a couple connecting rod caps, to look at the bearings. I'd also pull both heads to look at the pistons and cylinder walls. A lot of times, just pulling the pan and the intake off will tell you how hard of a life an engine has really had.

Gary

[Dead Parrot]

Did you see it run? If not, run it on a stand if you can and check for obvious leaks and smoke. If it passes that, just install and run with it.

Save your money and do a proper rebuild when you have enough saved. You either got lucky and have a decent motor or you didn't. If it is a good motor, you risk damaging something by opening it up. If it is bad, a few new gaskets and seals won't help.

The one exception I would make is new valve cover gaskets. Old ones always seem to leak and you can see the rockers and how clean or not that area is.

[68Gold/white]

First remove the intake, you can see the cam lobes clearly on a Big block. IF, IF one or more lobes are shiny all the way across, the cam is junk. It also means it's likely that cam lobe metal has been pumped all through the engine, and a rebuild could be needed...If in doubt, post some pictures of cam...

Remove the oil pan, look for anything unusual...chunks of metal in pan OR in oil pump screen. Number on main and number one rod are both oiled last (farthest from oil pump. Remove them both. If the look good, you might be OK...might.

Take the oil pump apart, look for scaring or scratches, grooves worn into the pump's innard's...if it's all smooth inside, squirt some oil into it, and re-assemble...re-use...

Replace ALL of the freeze plugs, period.

Since the pan is off, replace the rear main seal.

This is how I would proceed...

So many folks get all anal about how to do things (NOT pointing a finger at ANYONE, here...) There doesn't have to be an absolute way to do it. First 8 posts are great information!!!

[69Tom]

Thanks for the info guys. I will take all into consideration. Need to get it cleaned up first before I do anything, however.

[68Gold/white]

Go buy a gallon of diesel, and one of those stiff bristles brushes like is used in a parts washer. THe diesel will cut all the slime and gunk...and cheap!!!

[69Tom]

Originally Posted by 68Gold/white

Go buy a gallon of diesel, and one of those stiff bristles brushes like is used in a parts washer. THe diesel will cut all the slime and gunk...and cheap!!!

No kidding? I had no idea. Good tip!

[68Gold/white]

Please keep us updated. I always like to see what a potentially vintage big block looks like, in any stage.
I have had the 396 out of my 68 for waaay to many years, but am getting closer to making that thing run again!!!

[truckster]

Originally Posted by 68Gold/white

Please keep us updated. I always like to see what a potentially vintage big block looks like, in any stage.
I have had the 396 out of my 68 for waaay to many years, but am getting closer to making that thing run again!!!

Big block torque is definitely a lot of fun, even the relatively "small" 396/402. And there's nothing quite like the sound of a big block V8 at idle.

[Tom]

Change gaskets, everything else is check-able if it actually needs replacing or not. If you have the cash an aftermarket modern cam would really wake that old thing up.