[Dauntless1971]

I picked up a late 1975 350 engine yesterday. I had a feeling water had got in the engine by the rust showing in places. It seemed the 6X-4 heads having been renewed would be worth the price of the engine. I can still see the grease on the camshaft gear and the pistons appear naked as the day the were born. Is there a chance I can just tear down the engine clean up all the parts and reassemble?

[hobbygto65]

I had a similar experience, I tore it down completely and cleaned it reoiled and greased it and put it back together with new gaskets.

[Sirrotica]

A friend of mine was given a 389 from a 66 GTO that had the heads removed, and sat in a ditch for at least 6 months. He had no money, and no job and plenty of time. He sets to clean and de-rust the entire engine, and although he had a used set of cylinder heads, he managed to scrape together enough for a gasket set, and a used mild aftermarket cam, and lifters.

He never removed the pistons from the bores, just oiled the heck out of the cylinders and removed as much rust as he could with sandpaper. He took the bearings out, and cleaned them all up, and re-assembled the parts. I never thought the engine would run, let alone run well. I was wrong, that engine ran very well in his 63 Tempest, and after he wrecked that car, the engine went into a 64 GTO convertible, I lost track of it after that.

Against the odds, and with very little financial input, he got it all back together, and it ran for at least a couple years, and he thrashed the hell out of it regularly. There is an example of how someone took what most people would have sent to the scrapyard, and made it work, with very little money invested. It says that even without a lot of financial outlay, and a bunch of determination, things can get fixed, and be serviceable.

Other examples I can think of are tractors, and construction equipment that sits for decades, neglected in a field, and someone can still get them running, and in a useable condition without a huge cash outlay.

I also have a 455 that has been sitting for years outside that I rebuilt for a friend in 1988, it's been covered up, but that's about it. It was never prepped to sit outside for 10 years or more. Gonna be bringing it home soon, and hoping i have good luck with it....

[Goatracer1]

I think it is amazing what condition an engine can be in and still run well. I'm not saying race it or drive across country but it can make a successful driver engine. I've had 2 engines that I never thought would run never mind run well. One was a 1966 421 that I bought frozen up. I got it to turn over and it ran with no noises or smoke. The only problem was a badly leaking front crank seal. The 2nd was a 1964 389 from a Catalina convt. I found in a junk yard. It had been sitting so long that a tree about 10 inches in diameter had grown up behind it. I bought the whole car for parts and had them deliver it. I not only got it to run but the trans and parking brake worked so I could drive it around the yard. Also no smoke and 1 noisy lifter. The fellow who was parts manager where I was working decided to "rebuild" his Chevy 307 over the weekend in the shop. After disassembling it completely he found he had the wrong rings. He reassembled it with the old rings installing them in no order and drove the car home.

[Dauntless1971]

Well clearly the water mixed well with the oil. Cylinder 4 took the most water in. You can see how it darkened the cylinder wall at the skirt. Appears to be a low mileage engine with stock pistons. It will be another day before I can drop the pan and see where the water really sunk in. The heads have two new valves and used ones from three different sets of heads. I had already sprayed wd40 and wiped down the rust in the cylinders before the photo.

[4dblnkldude]

Simply stated clean it and run it.

[25stevem]

I would surly not just clean it and run while you have it out it unless this was a 2bbl motor and you intend to keep it as such!

The 2bbl motors where assembled with GM Moraine 200 series bearings which are strictly low performance.
The 4bbl motors got the far better 400 series bearings .
Either way I would also step up to the 60 psi oil pump along with a new pump driveshaft.

While the heads are off inspect all the push rod ball ends for ware and even the start of flat spots.
The ends should be spherical and of course confirm the rods for not being bent.

Also don’t assume that the rear main seal is still good now even if the pan and the rear of the motor look fairly dry.

[turbo69bird]

I’d clean it up and run it myself. Doesn’t look that bad and I’ve seen guys take junk yard motors on horrible condition just to make a race, bolt their turbo stuff on it and run all season with it like that ��

Unless your gonna hot tank it , go through the whole thing re ring and bearing it and maybe gone it what’s the difference .course I’d bore scope it and see if the cam has rust on it , but honestly unless the bearing surfaces are rusted your likely good to go the rest doesn’t matter that much .

[Half-Inch Stud]

Well, it would have fired-up, and a bit of knock and boil after warm-up. Now it has a chance to run.

[25stevem]

So you don’t think there was any water left in number 4 that would have hydro locked the motor and busted something?

[Dauntless1971]

The engine was never started since overhaul. I suppose the owner was trying to freshen it up. I guess to do this right I will need to add some more tools to my collection. My 65 Tempest had a Chevy 350 swap started it was missing many Pontiac parts to make this an easy project. If I can dial in a cheap running engine before building a fresh 400-461 engine there will be much less chance of something going wrong. Even now my plan is to first put the engine on a run stand. Certainly looks like a new cam and lifters.

Originally Posted by 25stevem

So you don’t think there was any water left in number 4 that would have hydro locked the motor and busted something?

[Dauntless1971]

Ok here is inside the oil pan.

[gtospieg]

That's kinda ugly...time to start tearing it down to clean it up....good luck, you never know.

[25stevem]

You can not run it like that, even if you where to just try and run it if the only rust was in the pan, that rust scale coming off would would chew up everything.

I think you need to have that block checked for cracks,.

[4dblnkldude]

Scotch Brite and a wire wheel on a grinder. No sweat, I've done worse than that engine. I'm a DIY'er. if your low budget and have more time than money I literally would not hesitate. I could type a few long stories in this thread but these engines are tougher than you think.

[Dauntless1971]

I checked the engine code YB for 75 is a 2 barrel version, though I have a non egr 72 Pontiac 4 barrel version to use. Now this engine does have etched numbers on the rods. And paint pen writing on the crankshaft along with what appears to be fresh bore holes and grinding on the rods. I am not to concerned about a cracked block seeing how it only had the water mixed with the oil, no water in the block itself. Just a little elbow grease and brake cleaner it is looking better already. I am probably going to get a few rod protectors and a decent torque wrench, not sure my 20 year old HF special is up to the task.

Also not that I am going to replace the camshaft but very interested in seeing if it is marked to at least know what it is. I put the lifters in order not that it matters seeing they were never broken-in. I will attach a photo maybe someone can tell the brand of lifter.

[SRR]

Wow! great job, just keep cleaning and take that lifter apart, clean and inspect.

[77 TRASHCAN]

That single lifter looks like what Sealed Power used to sell, back in the day. I'd disassemble that lifter. See if the light rust will clean off and allow free movement of the internal parts.
Go to Oreillys and get some evaporator. Turn the engine back to intake side up. I'd first try using evaporator on a rag and wiping rust off. You may have to gently spray it from the underneath, and wipe off.

If your cam has never been run, it will be fine.

[Dauntless1971]

That exact lifter was cylinder 8 exhaust it was the only one that had a light trail of rust going right to it from the cylinder head. Really just the smallest ring of rust on the top of it. The oil pump appears new with a tag and the number M54D. I figure it is a stock replacement version. Is it possible to open it all up and clean also? Or I am in need of a high volume standard pressure oil pump? Once I remove the pistons and the crankshaft if the bearings appear new any special way to clean the crankshaft oil passage?