Re: C20/cummins 12 valve
 

I’m looking for a suburban for it. Cummins engine was going into the C20 but a few members recommended that I keep it all stock, plus the 20 is running. Good suburbans are hard to find. So many scams.

I removed the injectors today and gave them a good cleaning. Hopefully this will fix my leaks.
Attachment 1866320

Attachment 1866321

Re: C20/cummins 12 valve
 

Looks like it worked!!! No more fuel leaks.

Re: C20/cummins 12 valve
 

Worked on the engine today but found another issue.
Looks like oil in my exhaust and all my injectors starting leaking again.
This engine was sitting for 10-15 years. Any suggestions where to start?

Re: C20/cummins 12 valve
 

You just need to get your injectors rebuilt with new nozzles. The are you cleaned is not where the diesel leak is coming from. On the turbo, the turbine shaft seals are more than likely stuck and allowing oil to go past and into the exhaust. That turbo is not that great so if I were you I would just get a new or rebuilt HX35w. It really depends how much you want to spend.

Re: C20/cummins 12 valve
 

I just ordered a new set of injectors from THD.
Will the HX35w be a bolt on or will I need to change some things?

Re: C20/cummins 12 valve
 

The HX35 bolts right on. But, you won't be able to reuse your stock intake cross over without an adapter boot. IMO I'd just put an intercooler on and put a different intake horn on and be done with it.

Re: C20/cummins 12 valve
 

Did a little shopping this morning.
Attachment 1869004

Re: C20/cummins 12 valve
 

Almost got all the parts.Attachment 1869054

Re: C20/cummins 12 valve
 

I think I got everything I will need.
Attachment 1869321

Re: C20/cummins 12 valve
 

How can I make this work?
Attachment 1869486
Do I need to change this wastegate?
Attachment 1869487
Is this the correct way to have it setup?
Attachment 1869488

Re: C20/cummins 12 valve
 

Monte, you have a 2nd gen upper there not a 1st gen style. I have a chrome one I'd sell reasonably. You won't be able to use that 1st gen upper with a 2nd gen intercooler tube so either way you will have to modify something. Either you modify the throttle bracket or you modify/build the intercooler tube. Here's a pic of what a 1st gen intercooled upper intake looks like.

Re: C20/cummins 12 valve
 

Just keep in mind there is really no correct way on what you’re doing, after all a cummins in a c series truck will never be “correct.” Now on that note you can go wrong on things, but as long as you don’t bottle neck the charge coming from the turbo to the intake you’re fine. My setup is an he351 and comes out 2.75” to a 3” pipe, 3” in and out duramax intercooler and then a modified P-pump intake horn. Silicone couplers/boots are available in many different sizes and step ups. I found the p-pump horn with a 24v plenum plate was the easiest way to clear the brake master cylinder.

Re: C20/cummins 12 valve
 

Thanks for the input guys.
I did a little shopping today San Diego and found Getrag speedometer adaptor.
Sucker was hard to find.
Attachment 1875795

Re: C20/cummins 12 valve
 

Then I found this beast!
Attachment 1881635

Attachment 1881636

Re: C20/cummins 12 valve
 

Nice find! Looks like a fun road trip as well.

Re: C20/cummins 12 valve
 

Yup. 1700 miles down. 300 to go.

Re: C20/cummins 12 valve
 

Wow that’s a haul with all that weight behind you. Is it a 20 or 1/2 ton?

Re: C20/cummins 12 valve
 

It’s only a 1/2 but the price was hard to pass up.
Just got home today 0730. Time for some sleep. Drove up Saturday morning.

Re: C20/cummins 12 valve
 

A good deal is a good deal. But it may work to your advantage anyways. You can always get an entire front end from a square body 3/4 ton, same as a 1/2 ton front swap. Then when you do that get the engine frame stands as they are the same angle as the 1st gen dodges and you can get away with stock mounts with very little modification. If you want I’ll post a picture of mine and a thought I had on how to redo them a little cleaner

Re: C20/cummins 12 valve
 

Madkid- yes please, Anything helps.

Re: C20/cummins 12 valve
 

Well just a quick snap of my mounts. The frame stands were off a square body, as well as the entire crossmember and suspension. I sliced the original 1st gen mounts and slid the engine down/rubber mount side up. Then just simply welded it up. One of these days I’m going to redo them. The plan is to take square steel and cut it diagonally at the same angle of the current mount and then drill holes to mount it to the block and rubber pads. It’ll be the same thing I have now just not welded together

Side note that notch was to clear my power steering lines, that is till I realized I notched the wrong side. That’s what I get for doing both at the same time.

Re: C20/cummins 12 valve
 

Little progress on the burb. Motor is in. Just need to figure out the wiring for it.
Had to Flip the intercooler upside down to clear the hood latch. Attachment 1901688

Re: C20/cummins 12 valve
 

Wiring is gravy, all you need to do is take your original ignition wire and put it to the fuel shut off solenoid, same thing with the starter wire, and that’s it aside from the battery cables Ofcourse. Is that a duramax intercooler? Looks similar to my flipped express can intercooler.

Re: C20/cummins 12 valve
 

I think it’s a Cummins. Sucker gave me hell to install.

Re: C20/cummins 12 valve
 

Where did you find this at, been looking for one for my truck?

Thanks!