Am I risking unforseen disaster?

[Jeff]

On my '84 International 10-wheeler dump truck with a DT466... I turned the fuel way up and adjusted the star wheel, as per the online instructions with pictures.
The truck is no longer an old pig. It roars up the hills. I can't believe it's the same truck that used to start choking at the mention of a slight rise in grade.
But yesterday near the top of a hill there was a loud noise like a tire blowout.
I found a broken hose clamp dangling in the engine compartment and then noticed I'd blown the turbo crossover pipe off the intake manifold. I had a new clamp with me and was back on the road shortly without problems.
But it has me wondering if I've created excessive intake manifold pressure and if that could cause major problems in the future...
- Jeff

 

[Greenbeast6.9]

Always have gauges BEFORE you turn stuff up!!!

 

[nevrenufhp]

I second that!
It's very common for the hoses to blow off after crankin up the fuel. The 466 can take about 50 pounds of boost before the threat of popping a headgasket. You will cause the most damage by too high of exhaust temps, that's what will melt stuff down.

 

[The Warden]

I third what they both said. You NEED an EGT gauge and a boost gauge before turning up the fuel...I would get them installed before driving the truck again. The damage may already be done

 

[towcat]

what did your MPG look like when you cranked the heck out of the fuel?
I got in trouble for getting my company truck reprogramed(DT466E). The bean counters figured it out when the mileage dropped like a rock.

 

[Jeff]

Thanks for the info...I'll get some gauges. I own the truck, and did figure I was taking chances by carefully following the posted on-line procedure with pictures...
The fuel milage is less, but not tremendously.
I appreciate everyone's prompt feedback.
- Jeff

 

[Exekiel69]

I'm interested as to what where the mpg #'s before and after this tunning.

 

[nevrenufhp]

On mine, it gained 1-1.5 mpg after the mods. Mainly it's the timing advance that upps the mpg.

 

[Jeff]

I'm sorry, Ex..., I don't track fuel milage and just top off after using the truck.

I did install the pyometer and boost gauges last week in what turned out to be a long saga. The exhaust manifold had had a hairline crack anyway, so after I (of course!) broke off the easy-out in the hole I'd drilled in the plug I ordered a new manifold. The new manifold ordered from the dealer came Friday with two (brass this time) plugs, but no holes drilled and tapped. I realized Saturday the bolts and studs ordered for it were all the wrong size. Removing two broken studs from the elbow off the turbocharger required cherry-red heat and almost and hour of back-and forth coaxing. Sunday night I had the thing together.
Monday I fire it up to move the backhoe. I got twenty minutes on the road with pyro readings (nothing dangerously hot) and I hear a little "pop" and lose all readings.
When I got back I pulled some dashboard apart after the ohmmeter showed full continuity between the blown side of the fuse and ground. I found a short in some old radio wiring someone had done. After re-wiring I had pyro readings again. 'Haven't used the truck since then. The truck's running strong though. The one surprise for me was the speed of temperature rise when you "pour on the coal", as well as the speed of cooling when you back off. It makes me realize you're monitoring the "fire" itself without an intervening heat exchange... -Jeff