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

[Dieselwrencher]

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.

[burnitg]

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.



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.




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.



Mounting the fuel filter and switching valve is next.

[lower50's]

Right on!!!

[Dieselwrencher]

Nice work. Everything is fitting in there nicely!

[burnitg]

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:



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.



Next, I have to modify the firewall for the tach drive.

[burnitg]

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.



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.



It's installed and looking good.

[Dieselwrencher]

It's always something! Nice work. I have used that same patch in a few cabs and really like them!

[LT7A]

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.

[goldenburb]

Been following along for information and entertainment. Hope to see it finished.

[lower50's]

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?

[burnitg]

Originally Posted by lower50's

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.

[burnitg]

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:



Here's the pan fitted:



Here's the pan welded:



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:



Job done:



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.

[OutlawDrifter]

Nice work!

[lower50's]

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.

[Dieselwrencher]

That oil pan turned out very nice!

Originally Posted by lower50's

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.

[burnitg]

Originally Posted by Dieselwrencher

That oil pan turned out very nice!




You are so right! I sure build them in my head faster than in life.

Me too!

[burnitg]

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.



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.



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:



And the passenger's side:



I still need to bend the oil supply tubing for the Jakes and new fuel tubing before I can start it up.

[mattfranklin]

Having fun following and looking forward to its completion.

[lower50's]

OHHHH it's getting exciting!!!!

[burnitg]

A bit of a setback...

I've been replacing all the old, hardened hoses on the engine. They look original so they are approaching 40 years old. I had replaced the 2 fuel hoses - from the pump to the secondary filter and from the filter to the head and was removing the turbo oil supply hose when Murphy intervened... The 1/8" NPT X 3/8" inverted flare elbow broke off in the block.




This is a photo of the broken end of the fitting. Unfortunately, my camera chose to focus lower down and the edge is not clear; but, the bright part of the break is where it broke when I attempted to take it apart and the dull part of the break is where it was cracked before. So, this cloud has a silver lining - the fitting was going to fail. It's better to have it fail in my shop than in the middle of nowhere.

Naturally, the fitting is in an inaccessible spot behind the oil cooler.



That's it just above and to the right of the white spot. I had to pull the engine out of the frame and remove the water pump, oil cooler, oil cooler adapter and oil filter to get to the broken fitting. Even with good access, I had a devil of a time getting it out. Whomever put it in the last time put some serious torque on it.

I've ordered replacement fittings from two vendors. Both websites showed the fittings in stock and available. After I placed the first order, I received a "backordered" email. I received another "backordered" email after placing the second order. Who knows, both orders may be coming from the same sub-vendor... At any rate, I probably won't get the fitting until after Thanksgiving.

While I have had things apart, I've been taking care of some issues that I had postponed and blasting and painting the parts that were removed.

One issue that I took care of was the dipstick. When I reversed the oil pan, the existing dipstick was no longer aligned with the oil sump. I drilled and tapped a new hole for the dipstick.



The dipstick is on the right behind the starter and the plugged hole where it was before is on the left. I would like to extend the dipstick so that it will be more accessible, I have a new longer stick; but, I haven't located the 1/2" X 0.035" wall steel tubing that I will need.

Hopefully, I'll have it running in early December.

[Dieselwrencher]

That's a good thing you found that broken fitting now. That would have been no fun to repair after the truck was all assembled.

[lower50's]

Silver lining in deed!! What kind of started are you using?

[burnitg]

Originally Posted by lower50's

Silver lining in deed!! What kind of started are you using?

I’m using a MASCO MA-10882. I've used it to turn the engine over a couple of times but I haven't used it to actually start the engine. I’ll know shortly if it’s up to the task.

I still have the original Delco starter if this one doesn’t have enough torque.

[burnitg]

It’s a runner!

I finally got the engine running. Unfortunately, it won’t start without ether. I think that the rings got stuck while it’s been sitting in my shop.

It runs well, has good oil pressure and makes glorious noise. I think that the new injectors made the difference. It was running poorly before I pulled it (but starting easily). One step forward and two steps back...

The new starter works very well. It spins the engine over rapidly. Of course it has low compression now - I’ll see how well it does when the compression is back to normal. I think that it will be fine.

[mattfranklin]

Originally Posted by burnitg

It’s a runner!

I finally got the engine running...

When I read this I got flashbacks. Good ones. I love the sound. We had a 4-53 in lab at school. It was a rush every time we ran it.