Can I take a cylinder head from the junkyard and install it right away, or would the timing be off?

[Josh P]

Rust is like cancer. It returns, spreads and grows. Factory coolant never changed or pure water will do that. I'd be confident the head could be ran as is. The JB Weld will protect the metal as much as it will help seal.

 

[rfishi]

I'm basically adding tiny bits of JB weld, letting it thicken up a bit, then gently running a razor blade over it to make it flush.

To be honest, I didn't prep the metal before applying the epoxy, but the small area I was applying it to didn't really have rust, the rust started a bit more inside the hole, so hopefully I'll be okay.

 

[Josh P]

That looks good.

 

[Turdle]

Don't disturb the epoxy until it cures, then, sandpaper on a block to level it down.


Shaving with a blade will pull It off the repair area..slightly but it will pull.

You'll just have to wait overnight for this one. Hopefully you didn't use the quick set version . It's about 25 percent strong as original.

 

[410Fortune]

This is at the “dead end” of a water jacket port. Water will be flowing into this cavity and then through the small hole in the gasket. Scale and crap buildup in these cavities over miles. That epoxy is trapped. Even if it did break free from adhesion it is still not gonna go anywhere but sit there until the next lucky wrench jockey pulls this head. We just don’t want it to break free and clog the hole

 

[rfishi]

I put the epoxy on yesterday and smoothed with razor blade, and waited overnight.

Now this morning I applied a tiny bit more, and plan to wait til tomorrow and sand it down.

I used original JB weld, it says its 5020psi strength.

 

[Josh P]

People with very old engines, where replacement parts are no longer available have to resort to this type of repair. I read about a guy that had a classic BMW with a cracked cylinder head. Oil was pouring out the side of the head onto the exhaust manifold. Some mechanics recommended a JB Weld repair, the guy thought they were joking. He tried it and the leak was gone. I've used it as body filler on a steel bumper. It never cracks like bondo eventually does.

 

[410Fortune]

I fixed a cracked 4.0 ohv w jb weld it held for years
My dumbass overtightened the oil pressure port in the side of the block
Later would learn that’s npt thread and tapered. Cracked the block
My friend Brett rescued me. He drained the oil cleaned the area, dried, let sit overnite
Cleaned and dried some more then carefully applied jbweld and threaded in the fitting. Let it cure for the think two full days

That held for like 8 years until my
Dumbass saw it was weeping a little bit of oil and tried to turn it. Jb weld came right off
I replaced that engine by the next Monday so I could get to work

Impressive repair ability on a cast iron block, on the outside of the block in an oil passage. Without jb weld this repair is not really possible and to hold as long as it did… thank you jb weld and mostly Brett!! Hahaha

This is where engine conversions come in, when an old engine and part is obsolete but the vehicle around d it is worth saving it time for a transplant
With 5.0 explorers the explorer rots out around the 302 lol

 

[Turdle]

It works for powder coating. Conducts, smooths, takes the extended heat.

 

[rfishi]

Can/should I clean my EGR valve with oven cleaner? I remove the EGR and manifold all in one piece, and wanted to clean up mainly the manifold mounting surface.

Will the EGR valve and it's tube be okay with having oven cleaner sprayed on and in them, followed by rinsing with water? Or could this damage it?

 

[Turdle]

Oh um. Worried about diaphragm inside egr.

I'd wash it with gasoline and brush, let it air dry

 

[rfishi]

it looks like there's a leak in the corner of the intake? What might I have done wrong last time when installing the intake gasket? How can I ensure it won't leak this time?

 

[410Fortune]

Prep

For a no leak gasket install it is all about prep! Clean surfaces and proper application of rtv in the corners

 

[410Fortune]

The lower intake gasket on these sits on the head gaskets or perfect alignment

The gasket gets some rtv in the corners where the heads meet the block before you set the gasket down and then some more on top of the gasket where the intake is going to sit in that valley.
Where the wall gaskets meet the head gaskets and lower intake gaskets again, dabs of silicon are required. Silicoln will only stick and stop oil if the metal surfaces it’s contacting are perfectly clean and free of oils.
I personally use alcohol to wipe surfaces clean because it’s $1 at Wally World far cheaper then acetone or carb cleaner or the like

This is engine surgery we must treat it as such, clean and prep is key to no leaks

The 302 is 1969-2001 this is an old design… back when everything was still
Metal and rubber gaskets were still new… not exactly the height of sealing technology so we have to do the work.
Use permatex ultra grey or
Black. Let it setup and skin over for 10-15
Minutes before setting gaskets or intakes

 

[rfishi]

I have permatex ultra copper, will this work?

 

[rfishi]

All of my rocker arms had slight play except for one which was very tight. Does this mean there's something wrong with the lifter?

 

[410Fortune]

Ultra copper is not for sealing intakes I would use grey or black

The rocker arms will have some play on them depending on the squish in the lifter and position of the camshaft
With the pedestal
Mount rockers there is no adjustment there is no lash to set… basically you torque to 24 ftmlbs and that’s it

I like to rotate the engine over by hand about 16 full turns and check the torque on every rocker a few times… this makes sure they are all torqued with the valves closed and springs not under tension … it is just good practice


The Lifters can squish some when they don’t have oil pressure so the looseness will go away once the engine is primed with oil pressure

 

[rfishi]

Ultra copper is not for sealing intakes I would use grey or black

I used the ultra copper only and am already bolting everything down. Am I ****ed? I only used ultra copper last time I did this, and it ran fine, but probably did have minor leaks.

I am doing this job completely by myself, have no friends or anyone to help; so with how difficult it was to line the heavy ass head and gaskets up and bolt them down with only 2 hands, it was almost impossible.

 

[410Fortune]

The copper will work fine, it is ultra high tempature silicon usually used around exhaust bits and turbos. It will still seal an intake just fine. Just not the exact correct application

Good Job! Dropping in a head and gasket in frame for sure takes some magic

 

[rfishi]

I've just drove it for the first time since the repairs, and everything is good so far. No leaks yet, and it seemed to drive with a bit more thrust. Tomorrow I'll be driving 40 miles to work so that will be a true test.

I forgot to tighten a hose clamp, so when filling coolant, that hose began to leak and dripped down in such a way that it looked exactly like coolant was leaking from the head/exhaust manifold. I almost felt like crying! Then when I realized it was simply a loose hose clamp, all I felt was sweet relief!