Thread: Need help with rebuilding my 302

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This will be the second time I rebuild my engine, the first time was when I blew a head gasket and had about 2 gallons of water in my engine and had to be towed home. When I took the engine apart there was some rust in each cylinder that I cleaned as best as I could... I started to take down the engine a few months ago and never got around to finishing and now I have rust in each cylinder again and from the block being exposed to the weather, its just surface rust but its alot worse then last time. What should I do? Please help.
- David

Surface rust is hardly a problem with an engine block. It could be bad if there is pitting in the bores or other dire areas, but with only a few months I doubt there should be any extensive pitting. If I were you I would strip the block and lightly hone out the bores with something like WD-40 or varsol. Just make sure to really clean that stuff out once you have applied it. Your rust problem should go away quickly. You could try a similar method with a light sand paper and solvent on the other areas as well. However, if there is rust everywhere, deck, bolt holes, cam area, mains, oil gallery, oil passages etc etc, then take it to a machine shop and have them hot tank it. Thats the best way to be sure there is no junk in your engine.

Can you please describe "pitting"? There is no rust anywhere else and I will go outside now and try WD-40 on the cylinders that have the most rust. I've used WD-40 when my head gaskets blew and it worked fine but I haven't tried it yet because it looked worse then the first time. Thanks for helping

I can describe pitting, it is little indentations that were caused by corrosion.

There is pitting And some rust in 2 or 3 bolt holes. So now what? About how much will getting my block "hot tanked" cost?

$$$, not shure about the true cost but, it is expensive.

My machinist only charges me about $12.00 to hot tank a block, but after it is hot tanked you will have to replace the cam bearings and the frost plugs. Depending on how deep the pitting is, the block may need to be bored and honed.

yeah, generally with a hot tank it is reccomended a magnaflux, which in total would cost you about $50, but then is garaunteed that you need to rebore the cylinders.... also, when you put that baby together, make sure you clean everything very very well, just a tiny bit of dirt, residue from rust, metal scrappings, or anything else, will eat the hell out of your bearings and crank, i reccomend you douse everything in break cleaner right before you put assembly lube on, that way you aren't gonna be bringing anything foreign into your engine