M1078A1 Broken exhaust parts

[Wingnut13]

Hey all,

So while swapping out the engine oil pump I pullled the exhaust down pipe. The one that goes between the post turbo 90* turndown and muffler. I found the first exhaust pipe clamp broken and obviously not supporting the exhaust anymore. Then I found my V-band cracked….. like almost 360* of it. And in two places.

I put it on the bench and welded it up. It’s now back in the truck and Happy, for now. So moral of the story is check yer first exhaust clamp post turbo for breakage.

 

[Keith Knight]

That’s crazy, what year is your truck?

 

[Wingnut13]

2003

 

[Keith Knight]

Same as mine, I’ll be inspecting that asap.
thanks for the heads up.

 

[Ronmar]

This is one of those places where alignment is important. Usually with a turbo involved there is typically a flexible section fitted into the mix to take any posdible strain/leverage being applied to the downpipe from the rest of the exhaust, out of the equation.

Since we dont have a flexible section, I would review the rest of the exhaust pipe and supports to make sure they are not imparting any force to that union.

 

[Lostchain]

So while swapping out the engine oil pump I pullled the exhaust down pipe.

Other than the exhaust issue, how did the oil pump swap go?

 

[Wingnut13]

There wasn’t anything difficult about that oil pump swap. As with most jobs there was just a lot of work. I dropped the driveshaft, exhaust, trans cooler hose carrier. The worst part was indeed the oil cooler bracket. The lower engine mount bolts weren’t terribly hard, then the passenger top was accessed from outside the frame topside. The bear was the top drivers side. After finding which 7/8” + 22mm wrenches 12 Point only of course fit it gave an eighth of a turn on each engagement.

I found a guy with a used pump I was willing to try. For $160 plus the time to do the job I figured I give it a go. I really just wanted to know which pump was installed on the engine. I have a 3126b, CAT told me I had the early pump. When I opened it up, it was the later gear rotor style. I did mess up by not having the oil pressure pipe seals on hand. I think those should have been swapped. I made the gasket for the oil pump pickup. That’s just a cardboard style from the factory anyways.

I did also switch to 10w-30 oil just to test worst case scenario for me. I haven’t been able to get the engine hot enough yet to know if it’s made a big difference. This pump acts differently, but the oil spec is different too.

Good enough to make three Memorial Day parades! For now, I’ll run it unless I get the low oil pressure light again. I will also analyze the oil to make sure I still don’t have any metal in the oil.

I might check injector o rings next.