Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

I have made some progress on the old GMC.

I made a bracket to attach the throttle, cruise control and engine stop cables to the top of the governor.

Here's a photo of the bracket:

Attachment 1468924

Here's a couple of photos with the cables attached:

Attachment 1468925

Attachment 1468926

I'm thinking I will use a couple of spark plug wire supports to organize the cables and route them over the top of the rocker cover.

I need to order a torsion spring for the throttle return spring since there is very little room between the back of the governor and the firewall.

I picked up some aluminum sheet in town the other day. Time to start working on the fan shroud...

Have a safe and happy Thanksgiving.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Slick job on the cable bracket.

CT

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Great work on the throttle bracket, and you have a Happy Thanksgiving as well!

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

I purchased a sheet of aluminum and got to work on a fan shroud. The OEM shroud was not even close and, at the time, it seemed like it would be easier to fabricate a new one. Well, about 20 hours of work later, here's the completed shroud on the workbench:

Attachment 1477726

Here it is installed in the truck:

Attachment 1477729

I like the look of it. I haven't decided if I will polish it or paint it.

I have been thinking about the upper radiator hose. The original elbow on the thermostat housing turned up. The outlet was about 1" higher than the inlet to the radiator. I mocked it up using some hose and tubing that I had on hand:

Attachment 1477727

This is clearly not good! I would have had a big vapor trap that I would have needed to vent somehow.

Thanks to Grigg over at 4btswaps, I found a OEM Detroit Diesel elbow that points toward the passenger side. I can easily make this work without causing a vapor trap. Here's a photo of the elbow.

Attachment 1477728

I have had no luck finding a pre-molded hose for the upper or lower radiator connections so I will make something out of tubing. At least now, I won't have the vapor trap.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Nice work and that worked out nicely to find an OE piece that would work.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Nice! i dig the shroud. that is in my enormous pile of to do's as well

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Happy New Year! It has been a good one for me so far. We had a great time with family and friends over the holidays. The Alabama Crimson Tide won the college football national championship. Roll Tide! The Broncos are in the playoffs. Life is good!

I've made some progress on the GMC. I mocked up the upper radiator hose. It looks a lot better with the new water neck.

Attachment 1487804

I am planning to fabricate the top pipe, including the elbow and reducer, from aluminum. I purchased the tubing and fittings for the radiator hoses and intercooler from Columbia River Mandrel Bending.

Attachment 1487805

I ordered the intercooler. Unfortunately, it looks like someone dropped it before it arrived. The UPS man came and picked it up for return.

Attachment 1487806

The replacement arrived and I fabricated brackets to support it and the condenser. Here's the top view:

Attachment 1487807

Here's the driver's side view.

Attachment 1487808

This is only the first pass, I know that the top of the condenser interferes with the hood latch so the brackets will have to be modified or I will have to purchase a shorter condenser. Two steps forward, one step back...

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

It's always something! Great work. That upper hose looks really nice with the new housing.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Subscribed

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

The intercooler is in! I have modified the brackets to bring the intercooler closer to the radiator and to move the condenser down a couple of inches. After the modifications, the hood latch clears the condenser.

First, I had to make some cutouts in the core support. I was going to have to do this anyway to make a pass through for the tubing from the turbo and to the blower. Since I needed to move the intercooler back, the nozzles interfered with the core support.

Attachment 1490038

I had to cut some of the structure of the core support out. I will reinforce it later.

Here are the completed brackets on the table:

Attachment 1490039

Here is a front view of the intercooler installed:

Attachment 1490040

Here is a rear view:

Attachment 1490041

Here's a view of the intercooler, condenser and hood latch:

Attachment 1490042

The elbows for my intercooler tubing are on back order, so I will be working on the brace for the hood latch and reinforcing the core support next.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

I finished the brace for the hood latch. I had to cut so much out of it to fit the intercooler, that I decided to box it. Here are the pieces on the workbench:

Attachment 1493340

Here they are welded up:

Attachment 1493341

Here it is installed (I had to fit the fenders and grille to make sure that everything still fit):

Attachment 1493342

I made an upper radiator pipe of aluminum. Here it is on the bench:

Attachment 1493343

Here it is installed (temporarily):

Attachment 1493344

Next is the lower radiator pipe. It is larger, shorter and has some odd angles. Should be fun...

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Fabricated aluminum water piping!! This build is getting real!

CT

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

The intercooler piping saga begins...

I didn't have the parts that I needed to complete the bottom radiator piping, so I decided to start the intercooler piping.

One major problem, the blower inlet points up. Here it is in the center of this photo (with the Gorilla tape around the inlet). I need it to point forward to meet the piping from the intercooler.

Attachment 1500007

Here it is in the vise awaiting major surgery:

Attachment 1500008

There's no turning back now!

Attachment 1500009

Welding cast aluminum - no problem - right? Well it was for me. This casting was full of inclusions. It was the devil to weld.

Attachment 1500010

I made a test apparatus to test the welds. Here it is in the apparatus for the first time. I obviously didn't have the clamps tight enough since there are bubbles around the gasket.

Attachment 1500011

By the time I got the two pinholes welded up, I had lots of practice in putting the housing in the test fixture. The pinholes were caused by two nasty inclusions. I would weld, test, grind, weld, test, grind, etc., etc., etc. I am not proud of the looks of the weld only that it doesn't leak.

Between the fitting, welding, testing and re-flattening the sealing surface, I must have 30 hours in this part. Good thing I'm retired - I would starve to death trying to make a living this way!

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

I'm impressed! I would have tried to hose the IC in somehow.

Welding porous cast aluminum, you're my hero!

CT

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

The radio is back! I had it serviced and the speaker re-coned by Crockett Sound Labs. It looks great, it will be a while before I know how it sounds.

Word of advice, if you are planning to have an old radio restored, plan ahead. The radio guys are really busy! I sent this radio to them 8 months ago.

Attachment 1500538

I had considered just installing the radio without having it serviced; but, decided against it when I saw how much of the interior I would have to remove if it didn't work. It's a good thing I sent it in, the output transistor was blown (common with these radios) and I would have been pulling it out again.

I got the blower inlet housing cleaned up and back on the engine:

Attachment 1500539

Now that both of the endpoints are set, I started working on the tubing for the intercooler. Here is the turbo to intercooler portion tacked and mocked into place:

Attachment 1500540

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Looking good! Before long you will be dripping oil all over town! LOL.

CT

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Nice work! It's coming a long nicely. I almost went the route you went on the factory am/fm but never found one reasonably priced I could talk myself into buying. Do they offer an option to add an input jack to these old radios by chance/

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Thanks for the compliment. After paying for the service and replacing the output transistor, mine is not reasonably priced either. Oh well, in for a penny, in for a pound...

They do offer to add a line in input to our old radios. I considered having one added; but, decided that it was not worth the additional expense. After all, I may not even be able to hear the radio over the music of the engine. I once put a nice stereo in a '91 Dodge Cummins. It sounded great until I started the engine...

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Nice progress! the piping looks great.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Subscribed. Looks awesome.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Intercooler piping - done!

I had to cut a couple of big holes in the core support to pass the piping from the turbo to intercooler and intercooler to blower. Here's a close-up look at the passenger side opening:

Attachment 1510276

I reinforced the openings on both sides. I believe the core support is now as strong as it once was:

Attachment 1510277

Here's a front view of the intercooler installed:

Attachment 1510278

Here's the turbo to intercooler piping welded and pressure tested:

Attachment 1510279

Here's the intercooler to blower piping welded and pressure tested:

Attachment 1510280

I need a longer coupling between the intercooler piping and the blower. I'll take care of that in my next Summit Racing order.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Lookin good, as always!

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

Great work!

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

I found some time to work on the old GMC today. I finally finished the lower radiator pipe.

Here it is on the bench:

Attachment 1516931

Here it is installed:

Attachment 1516932

The cooling system is now complete.

I purchased a hydro boost master cylinder since the vacuum pumps available for the Detroit Diesel look terrible. Next, I'll start on the plumbing for the power steering and brakes.

Re: Project Screamer - '72 GMC K2500 + DD 4-53T
 

How goes the struggle? The piping continues to please the eye