1938 V8 head removal

[38 coupe]

You need the big bar made to pull down on the valve guides. Also helpful but not required is a second set of hands to help put the keepers back in when putting everything back together. As mentioned before make sure you put parts back in the same hole they came out of.

[Bored&Stroked]

You probably don't need to replace the valves, just clean the stems and lubricate the guides a bit. Also, for the cylinder that had the water in it, would be a good idea to check the valve/seat faces for slight surface rust (as you know water went through them). If either is pitted, it will probably be an issue as far as valve life. You'll need a big ole' flathead valve bar to pull the guides down - to remove the horseshoe guide retainer clip. As your engine was recently rebuilt, it should be an easy job.

If the valves/seats are just slightly rusted, you may want to clean the valves with a wire brush (on a bench grinder) then just lap them in with fine lapping compound - to ensure a good seal. Then lubricate the stem/guide before reassembly.

Best Procedure: If I had the engine down to this point, I'd probably do that on all cylinders. It isn't hard to do and helps guarantee a good combustion seal. As other noted - make sure you keep all the valves/guides together as sets and replace them back where they came from!

By pulling ALL the valves/guides you can clean them all up, clean the ports, lubricate the guides and reassemble them. My guess is that you could easily do ALL of this over a weekend.


Tip: I take a piece of 1/16" stiff wire (like a welding rod) and I make a "hook" on the end of it that fits in the horseshoe guide hole. Then I make a "finger pull loop" about 10" up on the wire and I use this to easily pull the clips out while I have the guide pulled down with the valve-bar in my other hand.

[flatford8]

I didn’t see where you said you have the pan off. If I missed it, I apologize. If it was mine I would pull the pistons and clean everything. I’d be worried about debris in the rings and grooves. At least with the pan off you can put the pistons at TDC and see if the walls are rusted where you can’t see. Good luck with your truck and show us some more pics when you get it together........Mark

[BlueSpark]

Oh man... 2 steps forward... Was planning to button it back up today but I know removing valves and pistons would be the best thing to do. Its just pushing my scope of capabilities. I put each piston at TDC and sprayed gumout hard around each one to blow out anything that might be sitting on the top rings.Looking in with my best dollar store magnifiers I dont see any sign of rust or gunk. Then spun the engine for a while watching the valves go up and down, no sticking anymore and cylinder walls stay clean. I can see the guides and valve stems either through the intake ports or open exhaust valves, no sign of rust or damage is visible. And the valves/seats are clean as a whistle. Ill take another good look before making up my mind but now I am imagining rust between the rings and below BDC ring positions... Ughh. I figure the worst scenario with valves is if one sticks Im out $120 for another set of head gaskets to open it up again, this time it should be easy because I plan to put copper anti-seizo on the studs but the other possible problem is a different story-

[cadillac512]

What your plan is, has been done thousands of times and generally with good results. Yes of course taking it all apart is more of a guarantee that it'll be good but you aren't doing this for a customer or as a business. If you're willing to chance the gaskets and more work if something isn't up to snuff then put that sucker together after lubing everything you can lube and go for it! No guts no glory .



Terry

[BlueSpark]

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OK, its all back together. Put in some gas, fresh battery. Crossed fingers and put on safety goggles. Fire extinguisher at ready. And... guess what? IT RUNS! No blue smoke, no funny noises, no liquids dripping out. I need to fine tune the (new) carb and timing. Thanks again so much everybody, I will try to help with anything I can here to pay back (sort of limited to electrical stuff maybe but I'll do what I can).

[cadillac512]

Good job. Another one in the "win" column!


Terry

[38 coupe]

Sounds good, time for the driving season!

[Bill OH]

I have had a valve stick and you could hear the ticking. I put some MMO down the carb with engine running and I put about 12oz MMO in the gas tank. After about 1 mile it quit ticking. No further problems. And periodically, I put about 12 oz of MMO into a full tank of gas.

[Mart]

Yay! Glad you have it running. You did a great job.

[BlueSpark]

OK its running well and starts immediately every time. But Im a bit worried again. Today I changed the oil and what came out has a bit of a metallic look to it. Ill watch the new oil closely but should I be worried? I put a bottle of zinc additive in there too.

[cadillac512]

Originally Posted by BlueSpark

OK its running well and starts immediately every time. But Im a bit worried again. Today I changed the oil and what came out has a bit of a metallic look to it. Ill watch the new oil closely but should I be worried? I put a bottle of zinc additive in there too.

That's a bit hard to say, but if it's just a bit of tiny sparkle in bright sunlight no big deal. If it looks like it has silver/copper anti-seize mixed in, that's not good. Good plan to watch it closely.



Terry

[Bored&Stroked]

Run it with the new oil for a bit and then change it again - just to try to get as much crap as possible out of it.

Great job in getting it going!