[Silver Surfer]

There seems to be a few schools of thought here:
-Braze: David Vizard
-TIG weld: Melling
-Safety wire
-Do nothing: GM

How big of a risk is it to just let the interference fit work its magic on a performance street engine? Is the risk drooping down to the bottom of the pan or falling out completely?

 

[Mr. P-Body]

We always use a "tack weld" on small block pumps. They ARE known to loosen up and fall out. A wire-feed or "arc" is best. Brazing "works", but gets everything much hotter and can distort the housing. If the relief spring is "left in", it can also affect that.

FWIW

Jim

 

[Silver Surfer]

Pardon my ignorance, as I know very little about welding, but when you say wire feed, I am thinking you are talking about MIG, correct? My father in law has a welder and he says you can't MIG weld iron (which is what the pump body is made from, right?

I also take it that I should remove the plate and spring from the plate as well during this process. Do I need to wrap the plate in a welding blanket to let it cool down slow so it doesn't crack?

 

[cobalt327]

There seems to be a few schools of thought here:
-Braze: David Vizard
-TIG weld: Melling
-Safety wire
-Do nothing: GM

How big of a risk is it to just let the interference fit work its magic on a performance street engine? Is the risk drooping down to the bottom of the pan or falling out completely?

If you are going to heat the body of the pump by brazing or welding, you are right to remove the spring and piston of the relief valve first. And there IS a risk of the pressed p-u tube coming loose, if it's not installed correctly.

For securing the pick up tube w/o heat there are bolt on clamps. That said, I don't use either, instead I install a new pick up (do not reuse an old press fit p-u unless it's going to be thoroughly cleaned and welded IMO) using a home made tool, as seen here.

Here is a thread I have bookmarked- http://www.hotrodders.com/forum/oil-pump-pick-up-tube-install-sbc-185282.html. In it is some trustworthy info on brazing and for using a bolt-on clamp, as well as pumps w/bolt-on p-u tubes.

 

[2old2fast]

Pretty sure the pump is cast steel , not iron, therefore it is weldable. I've brazed 'em , welded w/ stick welder & the last one - bolt-on bracket, never had a problem..

dave

 

[[email protected]]

Pardon my ignorance, as I know very little about welding, but when you say wire feed, I am thinking you are talking about MIG, correct? My father in law has a welder and he says you can't MIG weld iron (which is what the pump body is made from, right?

I also take it that I should remove the plate and spring from the plate as well during this process. Do I need to wrap the plate in a welding blanket to let it cool down slow so it doesn't crack?

I've been MIG welding cast iron for over thirty five years!!

A simple tack with a MIG will hold tube to the pump. No heat buildup..

 

[Mr. P-Body]

What Bob said. A "tack weld" won't generate nearly enough heat through the whole body to cause issues. It's VERY "localized". Brazing, on the otherhand, requires the part to be "glowing" before penetration of the brass can occur. This WILL put too much heat in there.

As far as I know, except the modern "billet" pumps, they're pretty much ALL cast iron.

Jim