Official Caterpillar3116/3126 Thread

Hi Dave. Great write up! Just two questions. Is the core tested in or out of the housing? Do you have simular article on the aftercooler?

I did not test the core. I pulled the cores out and descaled in Rydlyme and did a visual inspection. I couldn't find any corrosion or other signs of deterioration, so I reassembled back into the powder coated shells, and reassembled onto the engine.

I did check the entire coolant loop with a pressure test rig I borrowed from Advanced Auto Parts. I forget the psi, but it held, and I concluded no further work/testing was required.

I have not dealt with the aftercoolers, but they are on my list. Ryan did his last winter so he may chime in on that subject.
 
I did not test the core. I pulled the cores out and descaled in Rydlyme and did a visual inspection. I couldn't find any corrosion or other signs of deterioration, so I reassembled back into the powder coated shells, and reassembled onto the engine.

I did check the entire coolant loop with a pressure test rig I borrowed from Advanced Auto Parts. I forget the psi, but it held, and I concluded no further work/testing was required.

I have not dealt with the aftercoolers, but they are on my list. Ryan did his last winter so he may chime in on that subject.

the aftercoolers are pretty straightforward. The core does not come out, the shell was welded around the core so it’s all one piece. There are a bunch of small fasteners, I think they’re 8mm and 22 of them, that hold the AC to the intake. You want to unclamp the boost hose from the turbo, slide it down and off the AC flange, loosen the hose clamps that hold the cooling water hoses in/out, then remove the fasteners. It won’t really drop down as it’s supported by the turbo but I held it up as I removed it. It’s pretty heavy, so be ready for it. The port side is worse that starboard because you don’t have as much leverage to lift and have to kneel on the engine.

call your local cat dealer and ask them who they recommend. A local shop to me is who they used, so I did too. They boiled them, cleaned as much as possible, and pressure tested. You’ll have to repaint them afterwards. The only additional part you need is the aftercooler gasket for reinstall.
 
the aftercoolers are pretty straightforward. The core does not come out, the shell was welded around the core so it’s all one piece. There are a bunch of small fasteners, I think they’re 8mm and 22 of them, that hold the AC to the intake. You want to unclamp the boost hose from the turbo, slide it down and off the AC flange, loosen the hose clamps that hold the cooling water hoses in/out, then remove the fasteners. It won’t really drop down as it’s supported by the turbo but I held it up as I removed it. It’s pretty heavy, so be ready for it. The port side is worse that starboard because you don’t have as much leverage to lift and have to kneel on the engine.

call your local cat dealer and ask them who they recommend. A local shop to me is who they used, so I did too. They boiled them, cleaned as much as possible, and pressure tested. You’ll have to repaint them afterwards. The only additional part you need is the aftercooler gasket for reinstall.
And replace that hose section between the turbocharger and cooler using the CAT part with new constant tension hose clamps. Make sure that hose installs dry and oil free with baby butt clean surfaces. 3126 are raw water cooled so there are probably broken pieces of the zinc's inside so a long soak in barnacle buster will dissolve. 3116 are cooled with the engine coolant...
 
And replace that hose section between the turbocharger and cooler using the CAT part with new constant tension hose clamps. Make sure that hose installs dry and oil free with baby butt clean surfaces. 3126 are raw water cooled so there are probably broken pieces of the zinc's inside so a long soak in barnacle buster will dissolve. 3116 are cooled with the engine coolant...

Ah yes I forgot about that. I did the boost hose and also the stubby sections coolant hose for the in/out of sea water. I also did all the other hoses on the engine at the same time since access was a little better.
 
Anyone know how to stop a 3126?
After running about 7 gal of antifreeze while down in the engine room how can you shut the engines down?
Thank you.

i do ours from the helm while feeding the strainer with a big bucket.
DE48781B-7822-458A-B352-3EE789B52A5B.jpeg
 
Check out this mcgivernism

haven’t tested yet

View attachment 114160 View attachment 114162

Ha, very cool. When I bought my boat in 2015, there were 2 similar setups in a box. Difference is, the brass fittings are machine threaded into 2 spare strainer covers. (engine and generator/ac size)
Return address on the box is Frank Webster's!
 
Carter,

I notice that your Cat engines were 350 hp 3126's. For you 300/350hp 3116's and 385/420 hp 3126's owners, the following list of parts may or may not fit your engines. Before shopping on line or going to your Caterpillar store for what you need, take your engine serial numbers and AR numbers with you and have the parts guy look up the parts you need by those 2 numbers. Might save you time and extra trips to the Cat store or return shipping.


Frank
any chance you know what racor micron size is specified for the 2136 CAT 2003 searay?
 

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