Normal amt of rust at drain plugs?

I drained by block today and was really surprised by the amount of rust I got out of it, especially on one side of the exhaust manifold drain. It was really tough to get off and then I had some big chunks of rust and what looked like sediment I fished out after I got it off. Im not sure the PO pulled all the plugs in the past. Im a little concerned about the corrosion I see on the threads, especially the manifold drains. See pics below:








I used some CRC Marine solvent to try and clean up the threads and the plugs some but they still look pretty corroded to me. Should I not be so worried about it or does this look like excessive rust. Anything I should be doing to clean and protect the threads on the boat side? Plugs are easy to replace, but what happens if the threads get too corroded on the the block or manifold? The plug on the bottom of the elbow at the water pump came out but its so corroded I couldn't get it back in, even after removing and cleaning the elbow. I ordered a new elbow to replace it with.

The block and the U are 1/4' NPT and the manifolds are 3/4" NPT. They are taper threads so you won't want to cut any deeper just run it in to clean them out.. Then get yourself 2 of these from here part number      4921K2 for the block,that way you can drain it easy with out having to remove plugs. You can clean out the threads on your old U pipe and put in a new plug into it. If you have already ordered you might just want to keep it,that is the only PCM Ford cooling casting thats still available,all others are sold out and sounds like there will never be anymore. And like Chris says the exhausts can be cleaned up,many soak them in muriatic acid for a bit. Don't know how mechanically inclined you are,it can for some be more work removing them than it's worth.

Is this what I need?

Gary, only fresh water. I will try to pick up some taps and give it a try.

I think I read some debate on her about using anti-sieze or something else when you reinstall the plugs. What about teflon tape?

Is the rust inside the manifold normal...nothing to worry about? Should I drain them or flush more often?

8122pbrainard wrote: Glen, The manifolds should be 3/4" so you'll need some bushings. I suggest brass and 3/8" drains so you'll need 3/4" x 3/8" bushings. If you go this route,

Sorry Pete, you lost me on the bushings. Are you saying you add them because of the length of the drain pipe? If the bushings are the same size, I don't understand where your putting them?

MrMcD wrote: A bushing is used to reduce the 3/4 inch threads down to 3/8.   You want 3/8 threads so one of the drain plugs can be used in that 3/4 inch hole in the manifolds. Bushings are available at a good hardware store. I always have a #8 nail with me when I pull my plugs, almost every year at least one plug is blocked with crud or rust. The nail quickly pushes through and opens it up again. I swirl it around in the hole to break up any rust around the opening. Keep something on hand in the boat to divert the water so it does not hit your carpets. The dirty rusty water coming out will stain.   Yep, done that with our old boat did not like it. Now I am more careful when draining.

Gotcha. So you guys use these at all 5 drains, including the J pipe, right?

Yeah I was brushing rust chunks up for while to get it off my carpet. Will plan better next time.

Just a few more hoses Gary, and you could make it Winterize itself every time you turned the key off.

Pipe threads are tapered so what you show is about right. I use anti seize grease on the drain plugs so they don't seize - also they don't need much torque to seal.

No,your good to go Glen. Don't worry about it

How do you probe with wire with a drain cock?

Bruce,
Through the years I've mentioned these removable stem drain cocks several times. They are fantastic and I highly recommend them. Here's the product description from McMaster:

"Removable handle stop cocks can be disassembled for cleaning."

I'm still in shock with that drain kit Skidim sells with the elbows. I'm surprised Vince still has them listed.

No tools needed,threads and seal are never disrupted and you can open it up while running to see if pump is pumping and if done a couple of times a year it keeps sediment out. I was surprised how much came out after running at Quinners this year.

I put the "T" hand valve from Grainger everywhere on mine. But recently I find that I prefer to go ahead and remove it and get as much sediment and rust out as possible.

I had to use bushings to make everything fit and the bushings seem to block the sediment. To each his own, I guess.

malcolm2 wrote: I put the "T" hand valve from Grainger everywhere on mine. But recently I find that I prefer to go ahead and remove it and get as much sediment and rust out as possible. I had to use bushings to make everything fit and the bushings seem to block the sediment. To each his own, I guess.

Clark,
What drain cocks did you purchase from Grainger? Were they the removable stem drains? I'd say they weren't since you can't get the sediment out and are the cheap drains commonly used for radiators. Why the bushings? What size did you purchase? The only bushings needed are for the exhaust manifolds.

I also have to ask you why Grainger? Their pricing is absolutely horrible and their web site is as well. The search feature doesn't get you were you need to go and I hate having to go through hundreds of listing to find what I need.