Exhaust single to dual on a tight budget - Then we get into some after issues

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bucket

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I really have no idea, it's been hanging around the shop for around 5 years. It was in a plastic bag with a label that said "Fiberglass header wrap". Nothing else. I know at one time it was in a cardboard box with a sheet of paper which likely had info on it but that disappeared at some point. I will probably just see how it goes next week and if the smell stops.

But it's not the self-adhesive type, right? Just the standard type wrap?
 

SirRobyn0

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Ok well this is where I'm at with shielding now.

Below: This is what I got done at the shop on Wednesday. @bucket no it's not self adhesive, standard wrap and clamp I did not wet it down before install. Not sure if maybe you can tell something by the color of the wrap. So wrapped the pipe, and put some of that heat reflective tape on the hydraulic hose. That tape is only rated to 200F, but I figure it's just another layer of protection.
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I briefly thought about wrapping the muffler, but went with the metal shield that I had purchased earlier. I feel that if I were to develop a leak in the hydraulic tank on the pump, the shield would more likely let it run off to the ground than the wrap would. The one concern about the shield is the edge of the shield and the hydraulic hose, I wouldn't want it to cut the hose over time. So I put a little of that heat resistant tape on the edge of the shield. I'm really not sure if that will last or not, but if someone has a better idea I'll listen. I tack welded the shield at each rib to the muffler. We'll see how that works out, if it's a problem I'll put a couple of those giant screw clamps on it.

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Next post I'll show the shield to pump clearance.
 

SirRobyn0

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Below, here you can see my crappy looking welds. I did this on the farm using the farm's Chicago electric welder. I can make strong welds with it, but not pretty welds. Need to use the shops Cornwell welder for pretty. Would have been a lot easier if I'd of welded it on before I installed the muffler. Well down the road when the mufflers need replacement I'll definitely do it that way. Anyway, it'll stay put.
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Below, pump to muffler shield clearance. I can stick my fingers in there and partially my hand, so yea it's pretty tight, maybe 2", hopefully that will be enough. I almost wrapped the shield around the pump, but if I were to develop a pump leak I didn't want it to collect fluid in it.
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Below here you can see where the shield hits the hydraulic hose. There really isn't anyway to reroute the hose, the best thing is just to protect it from being cut by the edge of the shield as best as possible.
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Below: A shot from underneath looking at the shield so you can see the spacing and edge of the shield.
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Below fuel lines to pipe proximity. I may make a metal shield to go around the switching valve, or I might just wrap this section of pipe. I'm undecided at this point.
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bucket

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I think it will all be fine how it is. Many hydraulic systems get pretty dang hot on their own, a little bit of muffler heat shouldn't affect those components.

The wrap I used was the basic white stuff. That bronze colored stuff is fancier and I think offered by several companies.
 

SirRobyn0

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I think it will all be fine how it is. Many hydraulic systems get pretty dang hot on their own, a little bit of muffler heat shouldn't affect those components.

The wrap I used was the basic white stuff. That bronze colored stuff is fancier and I think offered by several companies.
I agree, one of the guys at the shop thought any kind of shielding was unnecessary and overkill, and he maybe 100% right. To me running around the country side and into town, I even hauled a couple loads of manure before I'd done anything. It's more about not taking the chance with the truck and trailer going over mountain passes when the exhaust temp likely spikes. At the very least it gives me piece of mind.

All I know about the wrap is I have two 50' rolls, and I'll just see if that smell quits this coming week. Thanks.
 

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I yanked the wrap off the pipe today. I cannot stand the smell from it IDK what the deal is with this wrap but it smells like hell.

I'm going to do the basic vacuum operated water injection system. I'm not really sure when I'm going to install it. Going to ported vac on the vac advance, and tweaking the mixture screws has helped a lot, but I either have to run it a little rich at idle or put up with a little NOx smell. I'd definitely say it's tolerable, but being use to it with the cat, it's kind of not so great.

So what I'm doing is based on the simplest vacuum operated water injection possible. I'll mount a bottle to the driver side inner fender. For now it's going to be an old washer fluid jug. If I keep the system I'll buy a large universal washer bottle, and mount that. So the bottle has to be mounted lower than the carburetor so it will not gravity feed, and will only feed the carburetor with vacuum. I'm using 3/8" clear tubing, not because I need line that big, but because I have it on hand. The 3/8" line will get a washer fluid filter screen on the bottle. From there it'll run though the lid of the bottle up to a needle valve, and that will be what I use to control the flow. And then another section of vacuum line will run to the engine. The best line to run into would be the PCV valve line as it goes to the base of the carburetor and splits into each one of the primary barrels, so that should give the water at least as good of distribution as the fuel is.

The problem with that is adding water vapor, to the PCV line might end up plugging up that line with goo overtime, but maybe not. The canister purges though that same line so maybe that would ensure it stays clear. What do you guys think? I'm thinking I'll re-route the PCV line and Tee it into the brake booster line, that way the water injection can have soul use of that front port.

Calling this water "injection" I don't think is very accurate, because this thing is going to dribble it in much in the same way the carburetor does the fuel. It's crude and I'm aware of that. It will do nothing for full throttle operation, like a traditional pump operated water injection system. It will be active at idle, and part throttle anytime there is enough vacuum to draw it in. So mainly it'll be doing it's thing at idle and cruse. This should help reduce emissions, by lowering combustion chamber temps, which in turn will reduce the stink from the exhaust. Since it'll be active at cruise I will very likely be able to add some extra degrees to the vacuum advance without it pinging, as you know that will translate to better throttle response and improved fuel economy. I might be able to go back to manifold vacuum for the vacuum advance as well. But I'm putting the cart before the horse. First I need to install it and adjust it, and see what the effects are.

So for adjustment this is how it is done. 20mm travel of water in 15 seconds, is the starting point most folks seem to recommend, adjustment is accomplished by marking 20mm on the clear tubing and a stop watch to time 15 seconds out, using the needle valve to adjust the flow.

So there's the plan.
 
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SirRobyn0

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Ok so I setup the water "injection" last night. First lets talk about the setup, then we'll talk about the results.

So my first issue what where to have the water enter at. I knew I wanted it to enter where the PCV valve line goes into the carburetor, because it's at the base of the carburetor and would allow the water to enter both primary barrels, below the throttle plate. I thought about Teeing into the brake booster line so I could run the PCV to there, but upon researching that I realized that could negatively effect the operation of the power brakes and the oil mist that comes in might be hard on the booster if it ever made it into the booster somehow, like when your on and off the brakes a lot like on a long downgrade. So in the end I decided just to Tee into the existing PCV hose as close to the carburetor as possible and attach the water "injection" hose to that. I'm not concerned at all about water getting into the crankcase while the engine is running, but I do have the slight concern of it somehow getting draw in after the engine is shut off and during the cooling process. My answer is I don't think that will happen, but I'll be checking the PCV valve for moisture over the next few weeks.

So here is the connect to the carb. The line with the clear tubing is for the water.
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Below: This is the adjustment valve to increase or decrease the amount of water flow and you see those two sharpie marks, those are adjustment marks. They are 20MM apart and the starting adjustment is 15 seconds. So if the water is at the bottom mark it should take 15 seconds at idle to reach the top mark. I started with that but turned it up some on the way home so I'm probably at about 10 seconds or so. That valve is super sensitive and want to tighten it up some so it'll be harder to knock into it and change the water flow by accident. Which brings me to my next point. If I'm keeping this long term I need to put some sort of restrictor in the line, as it is right now if a person were to open up the valve a whole bunch it would be capable of bringing in enough water to at least stall the engine, maybe worse..... So that's something I'll do if I keep the system long term.
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Below: Reservoir, right now it is just water fluid bottle, wedged between the evap canister, the power steering hose and the radiator. For extra assurance there ziptie to the core support. Again if I'm going to keep the system I'll buy or repurpose an windshield washer reservoir and mount it low, because it has to stay below the carburetor to ensure it only feeds water by vacuum and not by gravity. At this time I've got $8 into the valve, everything else I had on hand, so it's a cheap experiment.

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The results. Last night all I did was hooked up the system and drove home. Keeping in mind that water vapor is good at lowering combustion chamber temps which reduces NOx, but it's not so great at lowering hydrocarbons (HC). So running ported vacuum to the vacuum advance creates less NOx but more HC. This was good back in the days of 2 way cats, where the cat could not clean up NOx. But it's terrible for water injection. The results last night on my drive home were the same smelly Hydrocarbons, I've had since switching to ported. So this morning I switched the vacuum advance back to manifold. The results so far have been promising. Keep in mind this is based on one, one hour long drive, but it seems much, much more tolerable both in the HC & NOx smells. It's it as clean as a cat? I'd say based of this morning, no it's not but it is a great improvement. Tonight I'll be driving the truck for about 2 hours so, some highway, some country roads, some traffic so I should get a much better idea as to how well it functions. Probably some fine tuning to do on the amount of water as well.

So I'll probably give an update tonight if I have the energy as to how the drive home went.
 

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Well. Just read this thread from start to present. Quite the journey.
 

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SirRobyn0

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Well. Just read this thread from start to present. Quite the journey.
Yea, and just one seemingly simple thing has lead to this rabbit hole.... But I'm getting closer to being out of it, and certainly when I can afford the cats I'll be all the way out of it.
 

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Ok more of the SRO Chit show. You got your popcorn @SquareRoot - Mike. :)

So what I discovered is that the valve I have simply lets to much flow and the adjustment is to sensitive to minor movement in adjustment. In other words if I crack it open 1mm it's flowing to little at 2mm it's to much, just the jostling from driving can be enough to cause it to change. What tipped me off was I went though 1/2 gallon of water driving home and coming back to the shop. WAYYY to much, but I can tell you that's also a pretty through decarb! So I readjusted it on my lunch drove it around to find the flow stopped! So tonight on my 2 hour drive I stopped repeated like to tweak the idle mixture and timing, leaving the experimental water injector setup in place but turned off. While the water injector setup might do what I want it to with another valve, what would I want after that? Change the hose size? Add a restrictor? I don't want to go down that road and frankly Mike is right, I've gone down a rabbit hole and I appreciate you pointing that out. So I'm going to leave it in place for now, but turned off. I may or may not fiddle with it further.

And really this was mostly for fun, because I'll have the cats by the end of next week, if not sooner which will make less emissions and smell from the tailpipes anyway.

I'm going let this thread go silent for a while, unless something earth shattering occurs.
 
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SirRobyn0

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Got the cats in this afternoon about 3pm. Went with Magnaflow units I'll try to remember to grab the #'s off the boxes. I laid under the truck for a few minutes after work. I really wanted to install them them, but it ended up being planning time instead which I guess is okish. I can get the driver side unit back in the stock location right at and slightly behind the cross member. Plan is to remove the mid pipe from the downpipe and the muffler. Install cat on to the end of the head pipe, cut off 13" from the mid-pipe and reinstall that. The passenger side is much trickier, mostly because the cross member is shape differently on that side the pipe goes under it rather than over it. So I guess I'll be installing it the same way and about the same position as the drivers side, but it's going to hang down a good bit more since it has to be under the cross member, or I'd have to mount it a little further back, where I could tuck it up, but that would put it right by the tank switching valve which I absolutely don't like. So lower it'll have to be. These cats are only shielded on one side and I plan to mount shield to the top and before summer I'll see if I can locate some additional shields to install on the bottom side as I wouldn't want to set a hay field a blaze.

But wait. All of that is on hold now because I developed a valve cover leak and of course the heater is sucking that smell right inside the cab.... Valve cover gaskets are coming so I know what I will be doing at lunch today...
 

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I used a magnaflo cat. 3" inch in/out. Good stuff. Cats like heat.
 

SirRobyn0

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I used a magnaflo cat. 3" inch in/out. Good stuff. Cats like heat.
Yes they do to a point. I know guys move them forward from the factory location, but since I still have a functioning air pump, and my old cat worked fine in the factory location it should be fine, my only concern is since it's dual exhaust now less overall exhaust will be flowing though it. So IDK if that will effect the cats efficiency, but I do know 4 cylinder carbureted vehicles in the 80's that had cats, so I'm thinking that it will work just fine.
 

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I still have the cats and I still haven't gotten the time to install them. I did do the valve cover gaskets, and the drivers side one was leaking at least a little, but the smell has persisted.

I could see that there was some residue around the breather tube, but it didn't run down the valve cover so not seeming like a likely cause, I went ahead and replaced the grommet anyway, which was dried out and cracked. But I got under the truck and found a good bit of oil above the filter area and on the plug wires. Hosed it all off with brake cleaner, but there was oil in the connector for the choke power oil pressure switch, and the plastic switch part is a little loose on the metal. Funny thing is that there are no marks on the downpipe where the oil would have to be dripping on, so I'm not really 100% sure that this is it, but it's the most promising thing I found. Possibly it just hasn't been doing this long enough to make much in the way of marks. But I feel like getting this burning oil smell coming though the heater thing takes priority over the cats... If it ain't one thing it's another, but I gotta take care of the truck so I don't have problems when I'm on the road.
 

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