Build The Clustertruck Rides Again - Refurbishing a 1975 Chevota

[RWBeringer4x4]

I ran into the same problem with Auto Zone vacuum plugs cracking. I bought an assortment of silicone plugs and solved that problem. I even used them on the brake bleeders.

Out of curiosity, did you buy an assortment of plugs as a "pack," or did you have to buy each size in large packs individually. Happen to remember where you got them? I was looking for high-temp silicone or EPDM plugs last night but it seems like most providers only sold them in 50-100 packs of a single size. Ideally, an assortment of sizes and about 10 each would be more than enough for my purposes.

I was also a little curious about the long term fuel resistance of EPDM or Silicone. EPDM seems to be hardier against chemicals but has a lower temperature tolerance (about 400 degrees, vs. 600 degrees for silicone).

And with that - I now realize that I've spent an hour reading about vacuum plug materials. I need more hobbies...

 

[mtquivr]

I bought something like this, but it's been several years. https://www.amazon.com/High-Temp-Silicone-Rubber-Protective/dp/B00XYDFW8K/?tag=ihco-20

 

[RWBeringer4x4]

I bought something like this, but it's been several years. https://www.amazon.com/High-Temp-Silicone-Rubber-Protective/dp/B00XYDFW8K/?tag=ihco-20

Yep, that's the one I found - just didn't like the cheesy colors, but it might have to suffice. Beats spending $20-$30 after shipping and winding up with 200 plugs in 2 sizes.

 

[Vae Victus]

Cheap Chinese "rubber" probably. I notice that every rubber piece on the cheap Chinese small engines rot in about 18-24 mos.

 

[bikersmurf]

In contrast, I’ve got plugs that appear to be original on my ‘72 SBC... the block heater failed at a young age of 46.

They just don’t build things the way they used to.

 

[RWBeringer4x4]

Cheap Chinese "rubber" probably. I notice that every rubber piece on the cheap Chinese small engines rot in about 18-24 mos.

In contrast, I’ve got plugs that appear to be original on my ‘72 SBC... the block heater failed at a young age of 46.

They just don’t build things the way they used to.

Yes, this is a common theme we see again and again when replacing our original FJ40 brake lines from the 1970's with their modern replacements. The originals lasted 40 years, if you get 10 from the replacements, you'll be lucky. It's probably the same reason my PCV valve is so loud too - cheap, aftermarket junk with sub-par components. I go to great lengths to find the "good" Chinese manufacturer for Gen 1 Chevy parts nowadays (because none of the parts AREN'T made in China). The struggle is real. Even AC Delco has outsourced. Working for a scientific instrumentation company, I understand the competitive pressures - we shifted production of a number of instruments from Melbourne, AU to Panang, Malaysia a few years ago...In order to stay in the game, you have to reduce the COGS on your product, but it's a sad state of affairs when you're constantly being nickel-and-dimed by 1 year old PCV Valves, or barely used vacuum plugs. Makes me wonder how long my Mexican-made 350 will run (although, in Mexico's defense, the stock crate 350s seem to have a pretty decent track record).

 

[RWBeringer4x4]

@bikersmurf - You're running an Edelbrock QJet clone on the new Small block, right? I know this is a loaded/sacrilegious question here on MUD, but have you investigated your fuel economy? 13MPG highway seems about OK to me, just wondering if I could dial it in further to squeeze out a couple extra MPG before I put stupid big tires on it and ruin my fuel economy.

 

[bikersmurf]

I’ve got an Edelbrock 1406 sitting on a SP2P2 intake. Since I was given it and it was virtually new I’m running it rather than one of the Quadrajets I have that are very worn and in need of love.

Unfortunately I’ve not driven it consistently enough to have calculated the MPGs.

With the drafty old Q-jet I’ve seen 17 mpg on the highway (33s and mild lift) and about 13 mpg around town.

Offhand I think the 1406 does at least as well... but I don’t know for sure. I’ve not even gone through the full tuning process. It came off a friend’s hot rod, and I’ve only adjusted the idle and tweaked the mixture screws a tad. That said they come tuned for a mildly upgraded 350 at sea level. It pulls well from below idle, and has good power higher up.

The Q-jets are awesome, but so far the 1406 hasn’t been pushed outside of its comfort zone. The “new” SBC also came with a lower mileage Q-jet that was likely original to the Fleetside it came out of. It’ll still need bushings and some loving. One day I’ll run some numbers and compare the two. For now I’m ok with the 1406 that will idle smooth below 650 rpm and also chug down the road at idle rpm.

 

[RWBeringer4x4]

Thanks @bikersmurf - I forgot you’re running an SP2P (me too!). I have to say I love that little intake. Completely gutless north of 4000 rpm but it really provides phenomenal throttle response down low. Not sure why it got such a bad rap back in the day.

I’d love to see 17 Highway (or at least better than 13) but it’s not a major priority. This quadrajet was set up for the 283. I ran the Quadrajet’s serial number and it seems like my primary metering rods/jets are about 10% too rich, and my secondaries are about 12% lean as compared to stock. Basically, the carb was set up to run about 80-90% on the primaries since he 283 couldn’t flow enough CFMs to really take advantage of a 4-barrel. The secondaries would open JUST a touch to give it a little extra kick when needed.

Aside from idle mixture, I haven’t fooled with anything yet - it transferred easily and runs shockingly well on the 350 - maybe just not as efficiently as I’d like.

 

[ToyotaMatt]

Out of curiosity, did you buy an assortment of plugs as a "pack," or did you have to buy each size in large packs individually. Happen to remember where you got them? I was looking for high-temp silicone or EPDM plugs last night but it seems like most providers only sold them in 50-100 packs of a single size. Ideally, an assortment of sizes and about 10 each would be more than enough for my purposes.

I was also a little curious about the long term fuel resistance of EPDM or Silicone. EPDM seems to be hardier against chemicals but has a lower temperature tolerance (about 400 degrees, vs. 600 degrees for silicone).

And with that - I now realize that I've spent an hour reading about vacuum plug materials. I need more hobbies...

NAPA sells 2 different small " TOYOTA " Sizes of Black 100% Silicon Super High quality Vacuum Caps , U can buy individually

NAPA part # 2-644 ( this would be used on the smallest Toyota Vacuum ports )

- TOYOTA part # 90339-03002 ( this little guy kicks A#S , it covers the 2 smallest toyota size ports and worth the $ in gold , i had them on a 15 year old 1995 T-100 and they never failed )

- Toyota Part # 90339-07016 ( this covers your 1/4" - 5/16" port size range )

 

[RWBeringer4x4]

Transmission tunnel is almost ready to go back in. I've spent the last week or so bodyworking it on and off with the help of my father-in-law. He's had plenty of practice lately with his latest project:

The goal wasn't to get it perfect, but to get it back in one piece and "good enough" to run. I figured this would make a good practice piece (having never done bodywork before) to give me a little taste of what's to come.

First, a recap. Here's what I started with. As those who have been following along recall - My transmission hump had a huge canyon cut down the center of it to account for a big dogleg in my transmission shifter. This allowed the shifter to clear the heater and make it to the transmission. The V8 was so far forward, the shifter had to go all the way to the firewall. The right corner had also been cut out of it with what appears to be an acetylene torch for reasons unclear. luckily, the piece in question had been bolted to the truck.

So with the help of my father-in-law doing the (ridiculously thin) sheet metal work, we set out to patch it up:

End result - ugly but functional:

After that, I stripped all the paint and the remnants of the asphalt "quilt" on the transmission hump. The paint was about gone all on its own, but the asphault was a pain, until I tried bug and tar remover. Since it was a tar based product, I figured I'd try it, since the wire brush was just smearing it around:

 

[RWBeringer4x4]

Not quite the final product, but the last picture I took of cleaning:

Next came body filler and primer - since I don't have an HVLP gun and didn't want to go to ridiculous lengths (sourcing gun, epoxy, and paint) for one body panel, I decided to stick with rattle cans for this one. Rustoleum self etc seems to work pretty well with body filler:

It took a couple of days of letting things dry, then going back in and knocking the high spots down with a body hammer and dolly, then re-priming and sanding, but ultimately, I got the majority of the lumps out. This was followed by some glazing putty to fill in the rust pitting:

Fully Primed and sanded - a layer of rustoleum filler primer went over this to close up and final deep scratches.

 

[RWBeringer4x4]

The came paint. The bottom got a coat rust converter, then Eastwood Chassis Black. I didn't put any real effort into cleaning up the underside just yet:

The top got a good thick coat of Duplicolor Ford Wimbledon White. There are a bunch of places on the forum that say this is a great match for T12 Cygnus White, so I figured I'd start there. A couple coats of Wimbeldon white, followed by sanding with 1200 grit. Then, it got a coat of Laquer clear coat.

I still need to sand out the clear (a couple run/fish-eyes) but I'm happy with the final product. It is FAR from perfect, with a few dings and scratches showing through and a couple bug inclusions in the clear coat, but it's a big improvement over where I started.

For those wondering if Wimledon White is a good match for Cygnus White - the answer is, "No."

It's far more creamy/beige than white - at least when comparing it to the faded, oxidized paint on the 40. Maybe if I washed/waxed/oiled the oil paint, it would get a more beige undertone. Either way, after the final sanding this will be going in - color match be damned. It'll get revisited in a couple of years where I get around to painting the tub.

 

[Vae Victus]

Rick, very nice job! As I've said before I have that same tranny hump - with cutouts to fix.

You mind asking your FIL what setting or amperage he was using on the welder? Or any tips from an expert (love the barehanded welding) on keeping the amount of heat vs weld deposit vs proper adhesion balanced?

Did you fill in all the gaps with spot welds or fill the gaps in the last raw metal photo above with body filler?

 

[RWBeringer4x4]

Rick, very nice job! As I've said before I have that same tranny hump - with cutouts to fix.

You mind asking your FIL what setting or amperage he was using on the welder? Or any tips from an expert (love the barehanded welding) on keeping the amount of heat vs weld deposit vs proper adhesion balanced?

Did you fill in all the gaps with spot welds or fill the gaps in the last raw metal photo above with body filler?

Yeah - my FIL is not big on safety - I'm surprised he even wore a mask...

We used my Hobart Handler 220V MIG welder for this, with .030 solid core wire and Argon/CO2 mix gas as that was what we had available. The metal on these transmission humps is THIN. I had 22 gauge steel laying around, which wound up being just a bit too thin - 20 gauge would probably be about right.

I've actually done a couple other small sheet metal things with my father-in-laws 110V Lincoln welder, and, for the light gauge stuff, I found it much more accommodating.

I wish I took some more pictures but hopefully this explanation will help:

The Hobart doesn't have specific voltage/wire speed settings in a very translatable language (just arbitrary 1-10 scale on voltage). However, we absolutely had the voltage on 1 (Bare minimum) then played around with the wire feed until we got the proper burn-in, without burning through. I THINK this wound up being around 20-30 "units." To fill the big canyon, we actually used a lap weld to make life easier. It's uglier, especially from the underside, but provided a more rigid, thick surface to work with. We cut a sheet of 22 gauge slightly wider than the gap, laid it in from underneath, and bent it to fit, and held it in with Clecos. Then we pulled out the clecos one at a time, and spot-welded through the holes. This gave us a double-thick metal to work with at the edges to help to avoid burn in or heat warping.

Once that sheet was in, we repeated the process, cutting a piece of 22 guage that fit INSIDE the hole, then drilled and cleco'd this sheet to the sheet underneath. Once spot welded in, we added a few more tacks - alternating sides and keeping them as spread out as possible to avoid heat warping. We just left it tacked in, then used a some 80-grit sanding discs on the air grinder to grind it back flush. Trying to weld in every inch of the panel would have been more likely to result in burn-through and warping. With the backing piece, there weren't really any pinholes "clean-through" to daylight (an issue for body filler).

As I mentioned, 22 guage was a bit thin - 20 guage would be better. Because the new metal was thinner than the old, it left a low spot in the hump that we had to compensate for with a thin coat of filler. The welded areas also wound up being a high spot (probably due to warping) so I ended up sanding back to metal to locate the high spots, and knocked them back with the pick end of a hammer.

The chunk cut out of the side of the tunnel was even harder. The gap was wide, and oddly shaped - but not really wide enough to weld in new metal. We ground all the rust off, mounted the hump back into the truck to help line up the cut-out piece with the rest of the hump. We then tacked it in where the metal was closest by SLOWLY building tack welds on top of one another to bridge the gap, allowing plenty of time to cool. We bridged the gap in about 3 places - so the process would be to build a tack in each place, then allow the whole piece to cool off for a couple minutes before repeating. Once the two pieces were stuck back together with the weld bridges, we pulled the hump out of the truck for ease of access, then slowly "stacked" tack welds to fill in the remaining gaps. Doing this, we had a TON of burn through issues, but eventually had enough metal that we could "sculpt" the metal built up in the cracks back to the proper shape with the sanding disc.

If you go down this path, my recommendation is:

LOW voltage. Setting 1 or 2, depending on the wire you're running.
REDUCE from .030 to .024 wire if you're running .030
WIRE SPEED: In this case, as long as I was getting hot enough to get a decent burn in, I wasn't worried about "perfect" penetration (it's not structural, after all). I would rather have a slightly cold, high weld that I can grind back, than too much heat resulting in burn through and a bigger, harder hole to fill.

I've heard TIG is better for this type of stuff, as you have a lot more control - but I don't have a TIG, nor do I know how to use one.

 

[RWBeringer4x4]

Another small update -

I pulled the aftermarket side-view mirror off my door tonight in preparation for some windshield mounted mirrors. In preparation, I started doing battle with the windshield hinge screws.

Several days of penetrating oil and wailing on my vessel driver - no love, they were jammed tight. Then I remembered a gift @Weber Sarge sent a couple years ago. A properly sized JIS bit in an impact driver and I had all 16 screws out in 5 minutes. I’m sure the penetrating oil helped.

In the process - I found another nice cancer spot that is probably indicative of the condition of the windshield frame... air this is what the corner looks like, I dread to think what the bottom of the frame looks like...

 

[RWBeringer4x4]

One other small annoyance I've run into -

Somehow, in spite of an anti-drainback check valve in my fuel line right before the carb, and having all the Welch plugs in the quadrajet epoxied, I STILL have a bone-dry carburetor after a day or two of sitting. I have to crank the engine over for a while to pump fuel back up to the Carb, at which point, it runs fine.

The fuel has to be going SOMEWHERE - the only thought I have is that my under-hood temperatures are getting high enough that the majority of the fuel is boiling off at shut down, and the remainder is evaporating thereafter. That said, I'm not seeing and fuel boiling into the primaries, nor am hearing any boiling (even with a stethoscope).

This is a great mystery to me as this particular gremlin has followed me through 2 carburetors, and 2 engines at this point.

 

[Vae Victus]

Nice move on the impact driver. Will have to remember that. I have a vessel driver, just glad I haven't needed it for a while.

Thanks for the description of the welding process. So you cut a sheet that lapped the edges, welded it underneath, and then put a piece on top of that that fit inside the hole. Correct?

Also, why is there a pi dev of sheet metal sticking out under the piece while he's working on the top side?

 

[RWBeringer4x4]

The key is JIS bits - If I'd mounted up a standard Phillips bit in that impact driver I'd probably have 16 stripped screws right now.

As for the welding questions:

1. Yes, the original piece of sheet metal overlapped (underlapped?) the transmission hump's sheet metal and was welded in. This gives you a backing to weld the actual replacement piece to, instead of trying to line up a piece of metal in the gap and have it "floating" in space as you try to butt-weld it in. They make butt-welding clamps for these purposes, and the end result might be cleaner, but this was actually stronger, and, unless you pull the tranny hump and flip it over, you'll never notice the lap weld.

If this was a concourse level restoration I probably would have squared off the "gash" a bit more, gone to the metal supplier, bought 20 gauge instead of 22 gauge, then cut a piece to fit JUST right, mounted it in place with butt welding clamps, used a copper spoon behind it as a heat-sink to avoid burn through, and spent a great deal of time ensuring the single sheet was correctly bent, lined up, and level with the surrounding metal. But this is the Clustertruck, it might be worth $50.00 someday, so it doesn't get special treatment.

2. The piece of sheet metal sticking out is because we intentionally cut the piece extra long. When dealing with curves and radii, it's difficult to know exactly how long an initially flat piece of metal needs to be in order to traverse all the bends and still be long enough to reach its final destination. So we cut it to width (slightly overlapping), and left plenty of length to traverse the bends in the transmission hump. Once it was tacked in, we trimmed the excess in line with the edge of the tunnel.

 

[RWBeringer4x4]

Made good progress this weekend -

I started by adding weather stripping to the bottom of the transmission hump - which I would 100% regret later:

I’d been keeping and eye out on my throw out bearing over the last 100 miles or so to make sure it didn’t wind up riding the pressure plate as things “broke in.” So far, no sign of an issue, there’s still a couple mm gap, so I installed the boots:

I also installed my new side view mirrors. I used to only have one, door-mounted, and the clamps had failed (and the tightening screws were stripped and seized) so the mirror would blow in at anything faster than 35mph.