sealing engine

[bigbadblue]

 My usual routine with a fresh engine is to put in straight water just in case there is an internal leak. After a short run add antifreeze and stop leak. After returning from MCACN I noticed a leak. Dang, looked like the back plate of the water pump. I had this happen once before. Cussing myself while taking this freshly painted and detailed engine apart
Well, turns out it was not the back plate but the little pipe between pump and manifold. Noticed excessive rust around hoses and other areas. I think I should rethink my routine of using straight water on start up.
 What would be a better routine? What should I add to the coolant to prevent rust? Also when I install another short pipe, what should I use for sealant. I haven't been doing much engine work lately and not up on the latest and greatest sealants.

[GerryP]

That short period of running without anything but water for your startup is a sound practice.  That did not cause the rust on the bypass tube.  How long has the coolant been in the system and what's the mix ratio?  Coolant doesn't last forever.  The anti corrosion additives break down with heat cycles and time.  You can test the electrolytic capacity of the coolant with a multimeter (same for brake fluid) or a litmus test strip.  I recommend doing that once a year as part of a maintenance schedule.  There are no real secrets or pro tips other than make sure your coolant isn't corrosive.  And don't use distilled water, which is highly corrosive.  Tap water or deionized water is fine. 

[Urgefor]

Could always change the nipple/pipe from steel to brass.

Example:  https://stores.precisionoilpumps.com/fe-ford-intake-manifold-nipple/

[My427stang]

If it's leaking at a press in bypass tube, I would replace it and thread to NPT and use Teflon tape, although a good RTV will do wonders on the threads to.  Assuming it isn't concours, if it is, I may look for a metric tube every so slightly larger

If it's leaking at a threaded tube, I'd pull it make sure it isn't bottoming before it tightens, and seal it

If it's leaking at the hose, I like the Wittek (factory style) hose clamps far better than worm clamps, they squeeze without tearing up the hose.  That being said, if you use them, hold the body of the clamp with a open end wrench and tighten with a 1/4 drive socket and ratchet.  It keeps from twisting the body of the clamp

If it is a repop bypass hose with the ribs, you may never be happy.  When able on the concours builds I try to talk the owner out of it. However they make it, it's usually soft looks like it will fail even new

As far as water vs antifreeze, I have zero issues with immediately running water then getting antifreeze in it.  They do rust quickly with water even though at that point it isn't harmful and of course if someone forgets and the block freezes, it's a bad day.  However, if you are seeping rust at all the hoses, I feel like you have a clamp issue, hard hoses, pitted parts or need to tighten the clamps a little better.

I have never sealed hoses, but I wouldn't be afraid of light wipe of white lithium grease or silicone grease, sparingly, or maybe even some non hardening RTV

[bigbadblue]

 Thanks for the replies. I was always a fan of Permatex #2, well because that's what we had. I feel in concours class it looks correct. Cork gaskets are correct, but can be hard to seal without having Right Stuff oozing out all over.
 Windage tray is tough as it has oil ponding on it. The leak I had this time didn't come right away. After starting the engine this summer I had a drip hanging from a hose, Cussing the stapled clamps on the hoses, I got that one to go away. Then a drip on the back of the pump. Added stop leak, it went away. Then at MCACN a Judge docked me for a drip hanging. Then a short run in Chicago, unloaded at home, then I actually had a puddle on the floor, it was the pipe. That is why I am blaming corrosion, because it came with time.
 

[Falcon67]

Because race car/drag strip and aluminum radiator I run nothing but distilled water with some "water wetter" (Summit brand) for a little corrosion protection.  I also rig up my Stant radiator tester to pressurize the block before installation in an attempt to sort out any potential leaks. I run 351C type top end so depending on the shortblock there are multiple potential leak spots.  Add a motor plate type thing to mount a crank trigger, vacuum pump, etc and there's more gaskets and layers. I never, ever load a Windsor without a pressure test - wet intake good place to lose water, either front or in the back especially when mixing aftermarket intakes with various cylinder heads. 

[pbf777]

       I will always recommend against running just "water" in the engine even for the initial startup!  O.K., if it develops a little leak, it's a little more work to mop-up; if it's pouring out as fast as you pour it in, well...........it'll aid in the lesson learned. If you do have to go back and open up the cooling system to fix a drip, don't you have a clean bucket you can drain the "coolant" into and set aside to be poured back in later?   

       Many of the gaskets may not take-a-set until after a heat cycle, this particularly true of many of the race type head gaskets; and on the initial start-up with plain water it'll seep out onto the relationship of the block to cylinder heads, this then becoming trapped and leading to corrosion, which I have witness as being attributed to head gasket sealing failures later.   

       And yes, "Water-Wetter" only provides minimal corrosion protection.   

       Scott.