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1994 K3500 extended cab dually

@n8in8or's silence on my comment is deafening. I'm sure Nate's just ignoring it. Don't really blame him. He knows it's all in good fun.
Some times the skid steer comments are well-played. Some times they're over-played. Some times I know you're right and I don't want to admit it. All times I know it's all in good fun :)
 
Quick update. I've driven the truck a bit since getting the trans lines redone. The 2-3 shift was slow and I honestly couldn't remember if it was like that before I blew the line or not....which is significant, because it blew while I was in 3rd gear - it made me concerned that I hurt 3rd gear. So to test it, I hooked the trailer up and drove around nearby while datalogging the transmission with my laptop. I did some full throttle pulls, including in 3rd gear with the converter locked up, and the controller didn't show any slip in the transmission, so the transmission seems healthy. I've read of others complaining of a slow 2-3 shift after installing the HD2 kit, so I guess I'm not alone there. I'll contact Dana at Pro Built Automatics at some point and see if he has a fix for that.

Now that the transmission (and the rest of the truck) are healthy, I'll be putting the Moose from the Tahoe on it so I can do some real work. More soon.
 
The transmission on My truck, it has a 3 position B&M shift switch thing hooked to it, located behind the glove box.
When it would shift it seemed a bit harsh to Me, I pulled the glove box, it was set on the no.2 position, I tried the no.3 position and it then seemed like it was in one gear and shoving it into another before releasing the gear it was in. I then put it into the no.1 position which is suppose to be factory setting and it seems just fine. It seems fine from 2-3 shift. Next time I drive it I will check on that. It might be too that this shift programmer thing might have some affect on the shift even in the no.1 position. AFAIK the transmission is original and has over 260,000 miles on it.
 
The transmission on My truck, it has a 3 position B&M shift switch thing hooked to it, located behind the glove box.
When it would shift it seemed a bit harsh to Me, I pulled the glove box, it was set on the no.2 position, I tried the no.3 position and it then seemed like it was in one gear and shoving it into another before releasing the gear it was in. I then put it into the no.1 position which is suppose to be factory setting and it seems just fine. It seems fine from 2-3 shift. Next time I drive it I will check on that. It might be too that this shift programmer thing might have some affect on the shift even in the no.1 position. AFAIK the transmission is original and has over 260,000 miles on it.

I think all that B&M module does is increase the pressure in the trans, but I can’t recall for sure. I can control the pressure for each gear in the software for the US Shift controller, but that hasn’t made a difference for the 2-3 shift. I read a post by Jake of Jake’s Performance and he said the HD2 kit makes changes that address factory problems with the 2-3 shift, but the side-effect is that it slows down the shift timing. He said he has changes he makes that counteract the slowness, but didn’t describe what those are. Dana at PBA is very sharp regarding trans function and modifications, so I would think he’d know how to deal with it as well. I will be contacting him for upgrades to the Envoy’s 4L60 in the future, so at the same time I’ll ask him about the 4L80 2-3 shift.
 
About a week and a half ago, I got the Moose IP from the Tahoe installed on this truck. Since then, I've been working on installing a different (hopefully more sophisticated) electronic boost controller in the truck to control the aneroid, so in the meantime I've had the aneroid backed all the way off so it's allowing full fuel all the time. I definitely have to watch how and when I apply my right foot because it will sure make a smoke show. Even at light throttle this thing is so much more responsive than the old pump I had on. That old pump didn't have any response and was slow to spool the turbo. It's nice to have some pep now.

I've been having some issues with the line for my mechanical fuel pressure gauge losing antifreeze between the isolator and the gauge. I didn't discover this problem until after I put the Moose on and changed the regulator to 25psi. With the old regulator at 5psi I just thought the pressure was too low to register on the 100psi gauge I'm running (excessive, I know, at least for now). So last weekend I took things apart and filled it full of antifreeze again. After that I had a solid reading in the cab, but I didn't drive it since I was still working on installing the boost controller. Two days later I went to drive it and it was only reading 20psi on the gauge and then the next day was 15psi, yet the gauge at the regulator itself was still showing 25psi, so it's still leaking....gotta figure that out. I say this because I'm really curious if my fuel supply upgrades I made have allowed the Raptor 100 to keep up with this IP now. So far I THINK they have because the fuel pressure gauge is reading rock solid even though it's at a lower number, but that's certainly not conclusive. I also say this because now this thing makes black smoke all the way through the rpm range and it didn't do that before, so that also tells me it's shoving more fuel to the injectors than before. On the flip side of that, it will only make about 29psi of boost. Before, when I swapped from the Donaldson air filter to the AFE it jumped from 27-28 pounds of boost immediately to 32-33 pounds of boost. So either the intake I've installed that now has 2 90* turns in it (with one being a Donaldson cobra head) is too restrictive, or the porting I did to the heads is allowing air to flow through the engine better, because everything else is the same as it was on the Tahoe. I'll pull the air intake off at some point and test that.

It's running pretty good though. I need to get the boost controller working so I can tune the rate at which the fuel gets delivered. I used to launch the Tahoe at about 6psi in 2wd and that was about the limit of traction. I figured I could do more with this truck since it's a dually and heavy, so I tried 10psi. It did this instead. And it would have spun them for longer, but I had to get out of it so I wouldn't hit the barn. I sure wasn't expecting this heavy truck to do that.

dually1.jpg

That's the good news. Now the bad news. Before I took that picture, I was driving the truck around and beating on it, trying to observe boost and smoke at rpm. I made a stop at the grocery store and when I came out there was a puddle of coolant under the truck when I came out. Hmmmmm. I popped the hood and it was coming out of the overflow. Interesting. It was in the 60s outside and the engine hadn't gotten above 175 (which in itself is interesting since I'm running the supposedly "good" Delco 195 thermostat). When I got home there was more coolant coming out of the overflow, in fact you can see it in the picture above. This doesn't feel good. Overnight, I thought about it and convinced myself I have a head gasket leaking at higher boost or a cracked head. Bollocks. I checked my coolant level the next morning and it was exactly at the Full Cold line. Ok, maybe it was just overfull? I recently had a leak at one of the rear block-off plates and I hadn't really driven it much since then, so maybe it was still just overfull. And I cranked the engine and it wasn't hydro-locked, which I was afraid it might be if the cooling system was that pressurized. Hmmm. I picked up a combustion gas tester from Napa to see if that told me anything. During that drive, I hammered on it some more. Yep, more coolant came out. I can't think of anything else that would cause coolant to be pushed out like that now that I'm running more boost than before, when I didn't have a problem at the old boost levels, but I figured I should still test it. The fluid didn't turn yellow, but it definitely wasn't blue anymore.

dually2.jpg

So the top end's coming off. I'm going to have the heads pressure-tested and if they're good, machined flat. I skipped that step last summer because at that point I was still in a rush to try to get the truck together for camping (which I ultimately never achieved anyway), so shame on me. Hopefully the machine shop can turn the heads around quickly because I'm supposed to take the truck to Dinosaur Camp at KOS October 14-16, so that doesn't give me a lot of time to get it back together and sorted out, plus we're going on a vacation for 4 days before that, so even less time. Oh well, it is what it is at this point.
 
On the gauge line, isolator bladder is a pace to look. The fight you are having is part of the reason I gave up and ran without it on mine (not smart). Remember the isolator should be mounted as close to possible as same height as the gauge from ground. - no siphon effect.

On the real issue:
Take a clean tank, bottle, whatever you can find to hold a gallon or two liquid. Get a cheap one way valve on the end if a hose - like the clear plastic siphon kits with the check valve (see pic) put hose with one way In the bottom of the tank with the other end of the hose just 6 inches or so above the waterline of the tank.

Drain some of the coolant from the truck into the tank. (Going to drain the coolant anyways) Now rig the tester to the top of the tank. Obviously you have to make the system so that all of the air goes through the coolant not just picking up air in the tank above the coolant.

I have seen old test chemical fluid react with just certain types of coolant slightly.

Fingers crossed and a little prayer you find same reaction and don’t need to pop the heads.

AA396015-DD43-41BB-B403-123D3723B9F5.png
 
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On the gauge line, isolator bladder is a pace to look. The fight you are having is part of the reason I gave up and ran without it on mine (not smart). Remember the isolator should be mounted as close to possible as same height as the gauge from ground. - no siphon effect.

On the real issue:
Take a clean tank, bottle, whatever you can find to hold a gallon or two liquid. Get a cheap one way valve on the end if a hose - like the clear plastic siphon kits with the check valve (see pic) put hose with one way In the bottom of the tank with the other end of the hose just 6 inches or so above the waterline of the tank.

Drain some of the coolant from the truck into the tank. (Going to drain the coolant anyways) Now rig the tester to the top of the tank. Obviously you have to make the system so that all of the air goes through the coolant not just picking up air in the tank above the coolant.

I have seen old test chemical fluid react with just certain types of coolant slightly.

Fingers crossed and a little prayer you find same reaction and don’t need to pop the heads.

View attachment 67222
On the isolator, it's a little lower than the gauge, so that's not ideal, no. I haven't been able to see where the leak is yet, since when I was fiddling with it last weekend I started the engine before I had the fuel line connected to the isolator and gave the engine bay a nice shower of diesel. Ugh. I have a suspicion that it's leaking at the parting line of the isolator, but again, I can't say for sure due to the wetness everywhere.

For the coolant, right now I'm running almost all distilled water. I didn't want to invest in a bunch of antifreeze yet since I was still shaking the truck down this season. I do have 2 of the little bottles of dye in it right now, as well as a little residual antifreeze that was in the block before I installed it. I understand what you're getting at with the test, but there are 2 things that are making me not want to do that: 1. I'm already about an hour into tearing it down. Sure, I could put it back together and give this test a try, but that sets me back multiple hours when I'm under a time crunch (yes, this could save time if not the heads/gaskets, I know) when 2. What else could be shoving coolant out of the system when I'm pushing high boost/cylinder pressure? The tester was really just a sanity test, and it's hard to get a good sample when it's only pressurizing the system at high pressures (no bubbles at idle). You've been around these a long time, so I'll definitely listen to any of your thoughts on this.......have you ever seen coolant pushed out for a reason other than heads or gaskets (or a block, yes, but this is the same block that was in the Tahoe, so I'm leaning towards the other variables first)? If you have another idea, I'll explore that, but right now I can't think of another reason unfortunately and I feel like my best course is to get the heads to the machine shop as soon as possible in the hopes I can get the truck back together in time for the event.
 
Dang. Pull it- I got nothing.

Thats why you get 100 times more done than me. I think all the possibilities and get analysis paralysis. You just turn the wrench.
I appreciate you putting the extra thought into it and trying to save me from myself! Don’t stop doing that.

I knew I was taking a risk last summer because the heads were off the engine that came in the truck and there were so many issues in it. I tried to compensate for that by using Chris’s technique of spraying multiple coats of copper on Mahle gaskets, but alas, it appears it wasn’t enough of a band-aid. Also, I’m not considering this a permanent fix either, just hopefully enough to get me through. The engine’s oil pressure is lower than it should be, so it probably needs cam bearings again. I’ll either be going through this short block soon or build another one and then put this one on the “to be rebuilt” shelf.
 
@n8in8or, I can't remember on this build (you have so many going on), but do you have a coolant to air CAC on this beastie? That could be your coolant/water overflow source when boost pressure climbs and is greater than cooling system pressure and pushes air into cooling system via a small internal CAC leak?

Just remembering the old Truckstop adage, new doesn't necessarily mean good.
 
Also, from my experience using the chemical combustion test fluid multiple times on the 94 Turbo Subaru with coolant passage issues, any color change - going green from blue, is a sign of combustion gases in the coolant.
 
@n8in8or, I can't remember on this build (you have so many going on), but do you have a coolant to air CAC on this beastie? That could be your coolant/water overflow source when boost pressure climbs and is greater than cooling system pressure and pushes air into cooling system via a small internal CAC leak?

Just remembering the old Truckstop adage, new doesn't necessarily mean good.

It’s liquid to air, but it’s not tied into the engine cooling system at all. Good thought though!

Also, do these heads have those valve seat crack head repair tubes installed in them?

Yeah, these heads have the tubes in them.
 
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