DIY Explorer 302 Headers

[410Fortune]

Hang in there! We need pics!!

 

[97Sandbox]

Pics of what? Haha. I can take a pic of soapy bubbles foaming out of the collector welds if you want, but I don't think that'll help anyone.

If I cut the passenger side back apart, I'll definitely take some pics of repairing the merge section (again). Right now, you can't see much.

Here's my driver's side flange delete mockup (using an old fox body heater as a jig).

The 16ga 1-5/8" tubing makes a perfect sleeve over the 1-1/2" tubing

 

[C420sailor]

It’s leaking between the pipes where they enter the collector?

What about fabbing a piece of sheet steel that the tubes pass through? Weld circumferentially around the tubes. Make it almost look like the tubes are passing through a hemispherical dome.

Otherwise you’re trying to weld deeeeeep down in a crevice

 

[97Sandbox]

It's leaking everywhere it was welded. A good bit around the merge star and a little where the collector was welded back on. I had thought about doing what I think you're saying, but there's just not enough room between the primaries to weld all the way around each one.

 

[C420sailor]

Damn yeah that’s tight

 

[410Fortune]

Dang
I wish there was a dip you could just drop them in and it would add a layer of metal

 

[97Sandbox]

Dang
I wish there was a dip you could just drop them in and it would add a layer of metal

Electroless nickel plating.

I'm just not sure if it'll be thick enough. I'm going to talk to some of my plating expert coworkers about it later this week.

I was going to blast the headers clean and plate them that way because my company doesn't do ceramic anymore. It's the only process that will get an even layer down where the primaries go into the collector (spraying ceramic can't even do that). I'm really not sure if it can fill pinholes though.

 

[CDW6212R]

Can that be applied to the inside? If the leaks are very tiny and the structure is solid, then maybe a coating inside might hold on.

 

[97Sandbox]

Yes, the nickel will build up anywhere it touches the steel. Of course getting the inside of the headers cleaned to bare steel won't be likely.

Hopefully I can at least get the welded areas cleaned, but I'll still need to cut the collector back off the passenger header to blast the merge section, so I may as well get the welds touched up first. That's my plan for now.

 

[C420sailor]

I’ve been thinking a lot about your collectors

Maybe the best way to approach this would be to have the pipes pass through a piece of machined flat steel. With the ends cut flush (I know, not ideal for flow) you could weld the ends of the tubes to the downstream side of the steel plate. Then weld the rest of the collector housing and downpipe adapter circumferentially to the plate.

If you really want that converging spike type thing going on, make the cones/spike out of scrap tubing in an assembly (pre-welded together) and weld that assy to the downstream side of the plate before closing it all up.

It’s hard to explain…I really should fire up SolidWorks

But this would keep all of your welds inside the collector, with the exception of the exterior housing weld. No trying to shoot weld between pipes.

 

[97Sandbox]

I’ve been thinking a lot about your collectors

Maybe the best way to approach this would be to have the pipes pass through a piece of machined flat steel. With the ends cut flush (I know, not ideal for flow) you could weld the ends of the tubes to the downstream side of the steel plate. Then weld the rest of the collector housing and downpipe adapter circumferentially to the plate.

If you really want that converging spike type thing going on, make the cones/spike out of scrap tubing in an assembly (pre-welded together) and weld that assy to the downstream side of the plate before closing it all up.

It’s hard to explain…I really should fire up SolidWorks

But this would keep all of your welds inside the collector, with the exception of the exterior housing weld. No trying to shoot weld between pipes.

I can picture what you're saying, I'm just not sure the results would be that different from what I'm dealing with now until I can find someone who TIG welds super well.

The primaries are slid into the collector then welded at the outside seam in their original configuration. I'd have to cut all that away to slide a machined plate over the primaries, at which point I'd be sliding onto bent tubing and I'm not sure you could get the plate to slide on evenly.

I bet that could be overcome with a lot of careful, iterative grinding with a carbide burr, but that's a whole lot of work we're talking about. And unless the welds seal just right, I'm in the same spot I am now.

After thinking through it, it's definitely a good idea for full replacement of the whole welded section at the collector (collector seam, merge star, and primary outlets). I'm picturing it's like a clover shaped cap for the collector with four holes in it which by default creates the merge star in the center. If none of the welding repairs get the job done, it's a potential path forward, but a long one for sure. I imagine it'd need to be 1/4 to 3/8 thick to make a strong enough sleeve -- drilling that would take a minute with a hole saw, but doable. Keeping it low profile enough to not interfere with the block on the driver's side or UCA mount the on the passenger side would be tricky too.

I just need a TIG setup (and free hours to practice) already...

 

[Jeff213]

Have you thought about silver solder to fill the holes? Just a thought that passed my mind the other night in a dream, lol. I am having some of the same problems you are with my set of torque monsters.

 

[97Sandbox]

I have thought about solder, but realized lead and tin wouldn't withstand the heat. I bet silver could, but I also don't know anyone who could do silver soldering. Maybe worth some research!

 

[Jeff213]

Oxy acetylene torch with flux to do the silver solder. It should withstand the heat.

The hard part will be getting them clean, enough to silver solder.

 

[C420sailor]

I’d be concerned about dissimilar metal stuff. Differences in expansion/contraction, potential for galvanic action, etc. I’d bet that silver solder cracks away from the steel after enough heat cycles.

I’m trying to envision what you’re saying, and I think we are thinking along the same lines. The issue I see with the current setup is welding in between the tubes, where they enter the collector—unless they’re welded on the inside/downstream side of the collector? Tough to envision.

I highly recommend getting a TIG setup. I went with a very high end Miller rig, but it’s overkill for a job like this. There are plenty of “third party” air-cooled inverter machines out there like Everlast that have a decent amperage and duty cycle.

Welding thick to thin is hard, but it comes with practice. generally, the trick is to run a smaller electrode and filler rod for the thin wall tubing, but with more amperage, and aim the torch more at the thick piece, so you’re putting more heat into the thick piece, and melting the thin tube with the edge of the arc. It is absolutely an art, but you have so so so much control over where the heat goes. It’s a double edged sword, until you get used to it. Once you do, and your puddle control gets strong, you’ll feel like a wizard. It’s great therapy, actually.

It’s way, way more effective than MIG, because you can control how much heat goes into each piece with your torch technique, and you can control the overall heat with the pedal. MIG on thick-to-thin often results in either poor penetration on the thick or blowing holes in the thin—you pick.

 

[410Fortune]

My $750 harbor freight multi process machine is arc tig mig 220v perfect for hobby use like this and well under $1000

I still have yet to take the time to learn the tig part, I have friends that can teach me. Tackle a project like this and it is time to learn.
Perfect Timing too because I have finally gotten very good at mig (self taught over last 20 years, learn by doing) and ask lots of questions!!!

 

[CDW6212R]

I need you as a neighbor too. I have a TIG/Mig machine from Eastwood, my friend loved to work with torches and some welders, but wanted to do aluminum work too. I've been too busy to push to any welding, I need to learn also.

 

[97Sandbox]

This project gave me a good opportunity to hone my MIG skills. I was a total beginner at the start of the project and now I may be approaching intermediate -- at least when it comes to thin wall tubing. Still not good enough, but so much better than when I started.

A TIG setup will be in my future, but it's not an expense that makes sense in my life right now. I'm hoping to learn the basics at work and casually look for a good used machine. For now, a real shop space and a half decent fab table are higher priorities.

 

[C420sailor]

If you’ve got an oxy acetylene rig, you can gas weld too. It’s harder and less controllable than TIG (in terms of heat), but the technique is very similar and it’s cheap if you have access to bottles.

 

[97Sandbox]

If you’ve got an oxy acetylene rig, you can gas weld too. It’s harder and less controllable than TIG (in terms of heat), but the technique is very similar and it’s cheap if you have access to bottles.

I don't, but it's on my list too. I've been looking for a while, but everything that comes up on marketplace is pretty pricey. Hopefully I can score a setup at a farm auction next spring.