Bumps on my 78’s rear tub/fenders?

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miker said:
I know this is blasphemy to some, but if you're running a v8 and have no distributor connection to that filter, it then makes a good place to connect your differential vents. That's what I've done. It does on occasion smell like gear oil in the cab when you are working the gears hard, but hey, I kind of like the smell. :D
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Yeah - just like that fresh ground coffee smell... Maybe you could start your own gear oil Miker fragrance line ... :grinpimp:

BTW - the random, left-side exhaust leak you heard when driving my 40 - do you think it could come from around that big 36mm nut in the SOR diagram below? I see some carbon/blow by down under around the inside of the fitting/threads. I'll see if I can get a picture up at some point.
exhaust.webp
 
When I had this setup on a 2F, I was always blowing gasket #1 because the nuts #12 or studs #21 would always loosen up. I think it was caused from normal heat cycles.

Have you checked these nuts and gasket?

If it is coming from #1 then I believe that I replaced the gasket and then double nutted the studs and that helped. At least it took longer for them to loosen up again.

I never had leak issues with the compression fittings like the one you pointed out.
 
I took a close look at that "number 1" area in the process of trying to figure out how to pull 26 and 27. In fact it may be hard to get off without breaking something. It looks all original/tight with a nice layer of heat-treated surface rust.

The bottom/back side of 27 looks like it's blowing carbon down the side of the pipe about 4 inches and there's a little "black" on the inside part of the nut.
 
It's all but impossible to loosen or tighten 24 and 27 on the truck, at least with the fender, steering and exhaust in place. 27 was pretty loose when I got mine apart. A couple days soaking in PB Blaster and I got them to move and tightened them both. The whole EGR system is kind of a hack job. I put mine back together without a #1 for who-knows-why. It leaks, as you might have guessed. The part # for #1 is 25628-61060. I think a copper crush washer that fit around the pipe would work well.
 
the black carbon is sure sign of a leak so l think you are correct to suspect this as a possible source of the noise. Exhaust noise was one of the most frustrating aspects of the 2F in mine. I could never keep exhaust fasteners tight even replacing them with OEM parts.

4" along the pipe seems like a long ways for the carbon to be along the pipe if just leaking from the nut/compression fitting, I wonder if the pipe itself is cracked?
 
miker said:
I know this is blasphemy to some, but if you're running a v8 and have no distributor connection to that filter, it then makes a good place to connect your differential vents. That's what I've done. It does on occasion smell like gear oil in the cab when you are working the gears hard, but hey, I kind of like the smell. :D
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That's blasphemy! :D
 
Excuse the iPhone photography - hard to get a good view of the nut. Image #2 is blurred but shows the extent of the black stuff. Up close I don't see a crack but I guess there could be. I assume 25/26 (SOR diagram) are some kind of sealing ring?

In real life this area actually looks better than the photos, threads/nut look pretty clean and silver-like - wondering if the factory applied any kind of goop/sealant to these parts when assembled. At the very least, at some point when the truck's hot I want to see if this 36mm nut will turn a little...

Because the upper area (SOR diagram #1) seems stable I'm thinking it might be a good idea to leave everything alone and keep an eye on it for a while. Luckily I don't have Mike's good ear - think I've only heard a little "mutter" of what could be an exhaust leak once or twice.
carbon.webp
 
Gusb said:
Luckily I don't have Mike's good ear - think I've only heard a little "mutter" of what could be an exhaust leak once or twice.
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LOL, well my wife tells me I need to get my hearing checked. :p

Looking at your pictures, I'd guess now that the black soot might be carried along the bottom of the pipe with water. Basically, normal condensation in your exhaust after startup that is finding a small exit in that joint and carying the soot with it and running along the pipe.

If you don't hear anything then I would suggest not messing with it.

I think the ring is a compression style that squeezes the pipe when the nut is tightened, the ring's outer surface also seals against the egr cooler body.

In my opinion, it may not be water tight but still not producing enough of an exhaust leak to worry about.
 
Gusb said:
at some point when the truck's hot I want to see if this 36mm nut will turn a little...
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I've got a bunch of large SAE tools, and a crescent wrench, but I would've needed to bend something to get to it on the truck. The large tools interfered with the frame. In retrospect, I did probably get it to turn a little, but I finally gave in and took it all apart. Then it was hard to hold the cooler.

A custom 36mm right-angle wrench would be just the thing.
 
Fast Eddy said:
I've got a bunch of large SAE tools, and a crescent wrench, but I would've needed to bend something to get to it on the truck. The large tools interfered with the frame. In retrospect, I did probably get it to turn a little, but I finally gave in and took it all apart. Then it was hard to hold the cooler.

A custom 36mm right-angle wrench would be just the thing.
Click to expand...

Don't ask me why Eddy - but I may have a 36mm crowfoot somewhere. Maybe with a 1/2 inch drive ratchet or breaker bar attached... it is a tight location.
 
Quick carb update - did a hot idle/air adjustment a few days ago. [Edit: also ran that vacuum line from the distributor cap to the air cleaner.] Out today in the truck and it's running better than ever (overcast wet day) - knock wood.

I don't have that many miles yet and it may be my imagination but the OME stuff I put on seems like it feels better all the time - it may be breaking-in. Maybe I should recheck/torque a few fasteners and make sure nothing is falling off. :grinpimp: Still want to do the knuckles and tear the steering box apart one of these days.

Got caught in the rain - kind of like owning a motorcycle again only wipers, lights, heater all going full blast and working :clap:
 
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cool. Nothing like getting caught in a downpour in an open top 40. Roughing it in style. :-)
 
Cleaning up the base areas on my hardtop sides where they meet the tub. Look like they're in pretty good shape. Probably prep and hit with with a little EP.
top1.webp
top2.webp
top3.webp
 
indeed, those are in great shape. All the hardtop pieces I have are like swiss cheese in those areas.
 
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