capping off heater nipples
 

I was wondering how you guys capped off the heater nipples on the engine?

I was told viton is a good amertial to use. I found it on mcMaster.com, but I lost the link.
Now the closest thing I can find is this http://www.mcmaster.com/#high-temperature-caps/=1mun3v
scroll down to the bottom. You can see it can resist a really high temp, but it says up to 10 minutes. I just want something to withstand hours of under 250 degrees.

How did you guys do it besides a bypass hose or welding it shut? I don't want to trust regular rubber vacuum hoses with silicone

I'm with you, I didn't trust a cap to work there either. I went with a bypass hose to route the heater line, just went to the auto parts store, asked them to look at their selection of hoses, and found one I thought would work.

The pipe from the lower rad hose tot he heater core was pretty corroaded, so I junked that hose. I would really like to find some quality caps to put over still. It'll also make my engine bay a lot cleaner.

I should have ordered those viton caps when I had the link. McMaster might have taken them off their catalog. DOH!

I used the rubber caps from the auto parts store, that didn't work and they blew out.
I then used heater hose with a brass fitting in the end to cap it and a hose clamp, that worked.
My radiator is an AWR/Ron Davis and I had the heater outlet welded shut.

More recently I had the water pump housing outlet filled by TIG welding. The nipples on the motor are filled with Devcon (so my engine builder says will work). All of the nipples are pressed in, tap them with a hammer all around and then they will pull right out.

so does anyone know about this material? http://www.mcmaster.com/#high-temperature-caps/=1nmyp9
scroll to the bottom. I guess they took the viton caps off their catalog

Couldnt you pack them with JB weld?

That would probably be hard...

The hose and brass plug + clamp idea is great I wish I'd have thought of that. Looping it sucks, I ran like that for a while and hated it. Long ass hose running across the chassis = fail. I had the engine block port welded and used a vacuum cap for the radiator port, been working fine for 800 miles and constant 195* temps.

My car isn't a race car, actually my heater core failed. I thought maybe some people with race cars had a good idea.

So does anyone know about the material I mentioned in the link above? I had my heart set on viton, but I can't find it anymore. I think Mcmaster got rid of it in their catalog

The problem with silicon is that it is very susceptible to cutting. You will likely have a problem getting enough clamp pressure to make them stay on without having the clamp slice into them.

I used the Help rubber caps on my FC for both ends of the heater core line (the one low on the block and the one on the radiator outlet line). The one on the block failed twice - once by blowing off entirely at high RPMs and the other time by splitting at the clamp.

I can't believe that silicone would do any better.

Now I use a short piece of heater hose and the appropriate sized stainless steel bolt from Home Depot. Use RTV Black on the bolt before putting it in the hose, clamp it up and let it cure overnight and you should be fine. The heater hose holds up to abrasion so much better than the caps.

Good luck,

-b

Thanks, I guess that is what I am going to do. I was trying to think of something that would look real clean and neat too. But I guess i'll just do that

To plug all the unused water nipples on a race engine,

First clean the inside of the nipple thoroughly, ream it with a drill bit until it shines

Find a piece of metal that will just slip inside the nipple
(all thread rod works great)

Clean everything with alcohol or brake cleaner

Mix up some epoxy, coat the piece of metal, and slip it into the nipple.

Mine have held for years on my road racer.

what i did was used a brand new heaterhose and a fat stubby bolt from osh and just clamp both...
it works great