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Old 02-27-2018, 08:01 PM   #201
Dieselwrencher
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Very nice work and I love the all spicer pieces going in the drive line. I wouldn't mind having a lathe so I could build my own too.
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


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Old 02-27-2018, 08:12 PM   #202
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

subscribed , nice work
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Old 02-28-2018, 03:20 AM   #203
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Quote:
Originally Posted by Dieselwrencher View Post
Very nice work and I love the all spicer pieces going in the drive line. I wouldn't mind having a lathe so I could build my own too.
I don't have a lathe either, so this will be an experiment. I've always wanted to try making my own shafts, all I have to lose is some 2" tubing.

I will have to take it to a driveline shop for balancing at any rate. If I can't achieve acceptable runout myself, I will cut and fit everything and have them true,weld and balance the shaft.
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Old 03-24-2018, 10:48 AM   #204
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Love this build . Can't wate to see the finished truck
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Old 04-05-2018, 02:06 PM   #205
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Cross Member Part 2/Rear Transmission Support:

As I designed the cross member, two things determined the height. 1) I needed adequate clearance between the bottom of the transmission and the top of the isolator bolt and 2) I wanted the front drive shaft to be level from the front of the transfer case to the center bearing. It turns out that the front drive shaft was the determining factor.

I decided to make the cross member of 1/4" plate. It is 1" thick and 8" deep. The depth allowed me to put the transmission support where I wanted it and allowed the center yoke of the drive shaft to fit around the transmission.

Here's the first mock-up of the cross member:

Name:  Cross member mock-up.jpg
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Here's the cross member installed:

Name:  Completed cross member.jpg
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I made the rear support for the transmission in a wishbone shape so that I could incorporate all three support studs on the rear of the transmission. Here it is with the standoffs tacked in:

Name:  Rear transmission bracket tacked-up on the workbench.jpg
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I used a single poly isolator, the same one that I used for the motor mounts, to isolate the rear support from the cross member. Here they are assembled on the work bench:

Name:  Cross member and transmission support on the workbench.jpg
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Here they are installed:

Name:  Cross member and transmission support installed.jpg
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I'll work on the front drive shaft next.
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Old 04-05-2018, 02:18 PM   #206
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Nice work on the support and cross member.
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


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Old 04-10-2018, 08:36 PM   #207
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Nice!! Looks like it should work just fine.
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Old 04-12-2018, 07:08 PM   #208
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Front drive shaft - done! Only 997 items left on the work list.

I fabricated the front drive shaft. It fits neatly around the transmission.

Here's the side view:

Name:  Front Driveshaft - side view.jpg
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Here's the top view:

Name:  Front Driveshaft - top view.jpg
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I have some things that I need to resolve while the cab is off of the chassis. One issue is the routing of the parking brake cable.
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Old 04-13-2018, 05:21 PM   #209
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Very nice work! I feel your pain on the 997 things left to do. A restoration is bad enough, then throw a conversion in there. Yeah, it is cool when it's done but boy they take a while to do right.
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


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Old 06-02-2018, 07:14 PM   #210
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Spring has sprung in the Colorado Rockies. I have been busy; but, not so much on my truck project...

I installed the parking brake cable. It fits properly and clears everything else. WooHoo! I would like to say that it was good planning; but, it was mostly luck.

Name:  Parking Brake Cable routing.jpg
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I fabricated a new bracket for the air filter/regulator. In the stock location, it interfered with the bottom of the cab. I installed it on the new bracket and tubed it up.

Name:  Filter regulator mounted.jpg
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Name:  Air Tubing.jpg
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I purchased an "Ultra Light Duty" air compressor and a small tank. [Who would call their product "Ultra Light Duty"? Where was the marketing guy when that name was picked?] At any rate, it was just the right size for my application. I installed the compressor on the skid plate and the tank on the chassis. I plumbed it up and tested it. The compressor will go from 0 to 105 psi in about 2 minutes. I get about 5 range shifts before the compressor starts again. It seems appropriate to me.

Name:  Compressor and Tank mounted.jpg
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Mounting the fuel filter and switching valve is next.
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Old 06-04-2018, 10:11 AM   #211
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Right on!!!
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Old 06-07-2018, 03:58 PM   #212
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Nice work. Everything is fitting in there nicely!
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


Tired of spark plugs? Check this out.
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Old 06-24-2018, 07:25 PM   #213
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Chassis modifications - done.

There's done and then there's done-done. The chassis won't be done-done until it's powder coated. Until that point, it's just done.

I installed a plate and mounted the primary fuel filter and fuel switching valve. I have 2 saddle tanks that will replace the one behind the seat so I will need the switching valve. I have the OEM mechanical valve; but, I cannot use it since it will only switch the fuel to the engine. I need a valve that will switch both the feed and return flows.

Here's the valve and filter installed:

Name:  Primary filter and switching valve mounted.jpg
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When I purchased the truck, the spare tire was just laying in the bed. I remember that my father threw the spare tire in the bed of his '72 after the first time he had to crawl under the truck to get it out. In my opinion, the OEM spare tire carrier was not a good design. I purchased a new spare tire hoist, made a bracket for it and installed it. I think that it is much easier to access and gets the spare out of the truck bed.

Name:  Spare tire hoist mounted.jpg
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Next, I have to modify the firewall for the tach drive.
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Old 07-20-2018, 07:19 PM   #214
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

More firewall modifications...

The trouble started when I realized that I had purchased the wrong tachometer drive. I purchased a 0.5/1 drive which would have been perfect for a 4 stroke engine. With my 2 stroke Detroit Diesel, the cam and balance shafts run at the same speed as the crankshaft. Since the tachometer is driven off of the balance shaft, I needed a 1/1 tachometer drive. The correct drive is 3/8" longer than the other one. When I lowered the body on the chassis, the drive hit the firewall just before the body mounts touched.

I got out the torch, body hammer and dolly and "clearanced" the firewall.

Name:  Tach Drive Clearance.jpg
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While I had the cab off, I moved the hole for the clutch rod, filled the throttle cable hole, filled the holes in the "A" pillar for the spot light and filled the gas filler hole.

The clutch rod was rubbing the bottom of the hole because of my 2" cab lift.

The spot light had to go because the handle was too close to the steering wheel and I kept banging my knuckles into it.

I'm removing the fuel tank from the cab and installing saddle tanks under the bed. I was able to buy a filler plate from Infanti Machine. It fit perfectly and saved me hours of work to shape this 3D patch.

Name:  Gas Filler Patch Fit.jpg
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It's installed and looking good.

Name:  Gas Filler Patch Complete.jpg
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Old 07-23-2018, 02:30 PM   #215
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

It's always something! Nice work. I have used that same patch in a few cabs and really like them!
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


Tired of spark plugs? Check this out.
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Old 07-24-2018, 02:58 PM   #216
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

This is a very interesting build. When my trucks burn oil it means they need new rings or valve guides. But I still like watching what you guys do to shoehorn in these diesels. Nice work.
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Old 07-24-2018, 07:50 PM   #217
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Been following along for information and entertainment. Hope to see it finished.
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Old 07-24-2018, 08:36 PM   #218
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

When new trucks get built they simulate everything with computers. When we build trucks we mock it up sit inside and hit our knuckles on stuff Where is the new fuel filler going to be?
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Old 07-25-2018, 12:11 PM   #219
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Quote:
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When new trucks get built they simulate everything with computers. When we build trucks we mock it up sit inside and hit our knuckles on stuff Where is the new fuel filler going to be?
The previous owner must have had small hands. I drove the truck for several years before I started this project. I can’t tell you how many times I hit my knuckles on that spotlight handle.

The tanks that I purchased have the fuel fillers in the wheel wells. With my 2” body lift and 2” suspension lift, I should have plenty of room to get the fill nozzle in.
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Old 09-11-2018, 05:47 PM   #220
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

All for another 1" of wheel travel...

From the start of this project, I have had serious concerns about the front axle contacting the engine at full spring compression. I measured the distance between them with the weight of the truck on the stock springs and determined that the axle tube would hit the oil pan about 1-1/2" before the differential housing hit the block.

Because I had to reverse the oil pan (in the original installation, the sump was in front and I need it to be in the rear) the turbo oil return would be on the wrong side. Since, I was going to have to modify the pan anyway, I decided to take 1" out of it and gain some wheel travel.

Here's the pan marked for cutting. The hole is where the turbo oil return was originally:

Name:  Oil Pan marked to cut.jpg
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Here's the pan fitted:

Name:  Oil Pan fitted for welding.jpg
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Here's the pan welded:

Name:  Oil Pan welded.jpg
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Because I moved the sump from the front to the rear, I had to add some tubing to the oil pickup. Here it is installed:

Name:  New Oil Pickup Installed.jpg
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Job done:

Name:  Oil Pan modifications complete.jpg
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While I had the pan off, I pulled all the main & rod bearings and inspected them. They all look good and the clearances are within new spec. I still need to do a compression check; but, I may not need to overhaul the engine.
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Old 09-11-2018, 10:20 PM   #221
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Nice work!
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Old 09-12-2018, 07:04 AM   #222
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

It's amazing how much time it takes to build something like this that most people never know. You are doing a great job, pan looks stock.
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1951 MG TD
1967 Jeep CJ5 1.9L TDI 33X13.5X15 Mud Grapplers.
1952 GMC 9700 p/u 7.3L diesel on air, dually
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Old 09-12-2018, 07:50 PM   #223
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

That oil pan turned out very nice!

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It's amazing how much time it takes to build something like this that most people never know. You are doing a great job, pan looks stock.

You are so right! I sure build them in my head faster than in life.
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1972 Chevy Longhorn K30 Cheyenne Super, 359 Inline 6 cylinder, Auto Trans, Tilt, Diesel Tach/Vach, Buckets, Rare Rear 4-link and air ride option Build Thread
1972 GMC Sierra Grande Longhorn 4x4
1972 Chevy Cheyenne Super K20 Long Step side tilt, tach, tow hooks, AC, 350 4 speed
1972 C10 Suburban Custom Deluxe
1969 Chevy milk truck
1971 Camaro RS 5.3 BTR STG3 Cam Super T10
1940 Ford 354 Hemi 46RH Ford 9" on air ride huge project


Tired of spark plugs? Check this out.
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Old 09-12-2018, 09:43 PM   #224
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

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Originally Posted by Dieselwrencher View Post
That oil pan turned out very nice!




You are so right! I sure build them in my head faster than in life.
Me too!
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Old 10-14-2018, 05:16 PM   #225
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Re: Project Screamer - '72 GMC K2500 + DD 4-53T

Tasks to get the engine running...

It turns out that I need to have the engine running to complete the compression check. Simply using the starter to turn it over, like I would with a 4 stroke, will not yield accurate results.

Here are the steps so far:

1) Battery cables - I could have probably jury rigged the battery cables; but, since I am starting the engine in the frame, I thought I might as well make the final ones. Here's a shot of the positive and one of the negative cables.

Name:  Battery cables.jpg
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These are very stout - 1/0 between the batteries and 2/0 from the last battery to the starter. I shouldn't have any voltage drop issues.

2) Rear main oil seal - I replaced the flywheel housing awhile ago but I didn't have a new rear main oil seal at the time. It was fine to not have the seal for mock-up. I put in a new seal and new pilot bearing.

3) Camshaft pulley - The original installation (C-70) had the fan running off of the camshaft pulley. In my installation, the fan will run from a separate pulley belt driven from the crankshaft. So, I needed to replace the pulley.

Name:  Camshaft Pulley.jpg
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4) New injectors - There were 2 stuck injectors so I replaced them all. I'm hoping that is the reason that the engine made so much smoke.

5) Jake brakes - Since I had to flop the rocker arms over to replace the injectors, it provided an opportunity to install the Jake brake actuators. Here's a shot from the driver's side:

Name:  Jake Brakes driver's side.jpg
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And the passenger's side:

Name:  Jake Brakes passenger's side.jpg
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I still need to bend the oil supply tubing for the Jakes and new fuel tubing before I can start it up.
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