My Uncle used JB Weld one time on a leaking freeze plug. He says it sealed it right up and he ran the vehicle without any issues from that point on.

 

Gary took a rat tail file to the bolt holes in the intake also. They were corroded pretty bad as well. That could have even been why the intake was binding when we were torqueing it. I plan to use RTV again on the ends where the water ports are and to replace the cork on the bottom. Also I am going to use some anaerobic sealant on both sides of both intake runners this time. That's how I did it the first time and I didn't have any leaks that I know of.

Besides the rear main seal, I have replaced the entire Mr. Gasket rebuild gasket set with Fel Pro by now. Guess what the only part of the motor that is leaking oil is?

 

Here is a question or myth to be busted by Jim or Bill. I had an old timer tell me one time that he could test coolant with a multi meter by checking the ohms or maybe even checking for voltage while the coolant was in the radiator. I was pretty young when I heard this so I had no idea how he was saying to check it. I don't know if he was saying to put both leads in the coolant or just the positive and take the ground to a ground.

 

Here it is from none other than Bobtheoilguy:
Coolant check w/multimeter - Bob Is The Oil Guy

Here is even a youtube video on it:

 

He's checking to see how much voltage is being generated by the "battery" created by dissimilar metals in the presence of an electrolytic - coolant. However, I believe he made it too simple as different combinations of metals will generate differing voltages with the same electrolyte. In other words, an engine with cast iron block, heads, and intake and a copper/brass radiator will have a very different voltage with the same current than an engine with cast iron parts and aluminum part.

This galvanic table shows aluminum as between -.8 & -1.0, while cast iron is -.4 to -.6, for a delta of something like .4. But brass is between -.2 & -.4, so an engine with a brass radiator and cast iron parts would have a delta of something like .2, or half that of the cast iron/aluminum combo.

As it turns out, most of our trucks came with cast iron/brass combinations so they are less likely to have problems than those with aluminum. (I'm ducking the cathode/anode issue and which metal is corroded.). But, the coolant still needs to be change regularly. And, for those of us that have added aluminum parts, like a manifold, radiator, and/or heater core it becomes much more important.

 

I had typed a long reply with charts and references.
It seems the IB servers ate it for breakfast.

Gary, it is easy to see why you are better off to have a more noble metal for the thin components of the cooling system than the thick and massive parts like the block.

 

Luckily a quick "back" on the browser got me to my message as IB tried to eat it as well.

And yes, it is better to have more "noble" metal in the thin components as the block could lose a little and not be harmed. And with aluminum being less noble than brass/copper you can easily see how important it is to change the coolant with an aluminum radiator or heater core - or intake manifold for that matter. Having said that, the corrosion takes place more readily close to the dissimilar metal interface, which explains why the intake manifold disappears.

 

I have to take Kris to his Gma's to mow. Then after that we are heading to Podunk to hopefully get the Bronco back together.

 

I tried "back" and I tried to resend the post.
FAIL!
The point is... that Brass and Copper are both more noble than iron/steel.
Aluminum/zinc/magnesium are obviously NOT.

 

Yes. I didn't mean to imply that brass/copper aren't more noble than iron/steel, but can see that my words could suggest that.

To clarify for others, in the case of the materials used in these engines, iron/steel are essentially in the middle of the range, with brass/copper being to the left or more "noble", and aluminum/zinc/magnesium to the right. The corrosion occurs on the "less noble" material, and mainly close to the interface although to some extent everywhere. So an engine with a steel block/heads/manifold and brass/copper radiator & heater core will not have a localized corrosion problem as there is no true interface between dissimilar metals. And, the corrosion will be on the steel components.

But an engine with a steel block & heads and an aluminum intake will have corrosion on the aluminum and that corrosion will be localized at the steel/aluminum interface - meaning the coolant passage where the manifold bolts to the head. (Except on Fords premium engines which don't have a wet intake manifold. ) So on these engines it is imperative to change the coolant frequently. And, by the way, some of the 2bbl 351W's have aluminum intakes from Ford.

 

Jim - I think this is an authorized hijack - Bruno is bored watching his son mow his grandmother's yard and is asking me what a Saginaw pump looks like as someone is advertising one, presumably on craigslist. So, could you post a pic here of the pump? How 'bout its bracketry?

 

Like I said, I'll post it in the WDYDTYTT thread,
Right now I have an issue with the recommended '77 4X4 F-250 pressure hose, and I don't know what to do.

 

Another FTE member has it here locally.

 

Jim, try what the pump came off of, it was probably somewhere between 83-87 E-350. In perusing AllData, the power steering hose on the pickups changed PN in 1987. It looks like the hose has to have a 16mm O-ring fitting at the pump and a 5/16" male inverted flare at the gear and be 42 3/4" long. The older trucks used a 3/8" inverted flare at the pump. The E-350 hose is too short by about 10-11".

 

Here is what one looks like in it's native element (E-350 with V-belt 460).