Official Caterpillar3116/3126 Thread

There is an electrical junction box on the forward end of the engines….hinged door with a latch…….everything in that box should stay dry. Everything else is made by Caterpillar to operate in a marine environment. Use a light degreaser like foaming Gunk followed by a light spray with a water hose then spray the engines with Purple Power to remove the degreaser residue. Just avoid spraying the water stream directly on the alternator, the starter connections and the junction box.
 
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Does anyone have the measurements for the propeller shaft diameter for the CAT 3116 with ZF85 transmissions? I think it's 1.5 inches. Is that correct and what's the diameter of the stern tube? I think it's 3.25 to 3.5 inches.
I think the PSS shaft seals are P/N 03-112-312

Looking to replace the leaky PSS Shaft seals with either Tides dripless or Lasdrop.
 
Does anyone have the measurements for the propeller shaft diameter for the CAT 3116 with ZF85 transmissions? I think it's 1.5 inches. Is that correct and what's the diameter of the stern tube? I think it's 3.25 to 3.5 inches.
I think the PSS shaft seals are P/N 03-112-312

Looking to replace the leaky PSS Shaft seals with either Tides dripless or Lasdrop.

they should be 1.75" shafts. our 2002 410 with the earlier version of your 85's (ZF80IV) uses tides seal 1750
 
I made my own impeller tool out of 3/4"-16tpi all thread rod then imbedded a small socket in the end so it can be driven by a racket. It will pass all the way thru the impeller and make impeller removal a snap.

I have 2…..one that fits a 3/8" rachet and one for a 1/4" rachet. Unfortunately they are temporarily lost in "boat left-over, never-never -land in one of many boxes of stuff in Florida or my shop in Tennessee……..they will turn up soon.
I have 5 bolts now, only need one, let me know if you need one. Otherwise I will make a small anchor out of the other 4
 
Last year I cleaned both of the Engine crankcase breathers in mineral spirits. I dried and reinstalled. Ever since then the port engine has only what I can describe as Blow by. Like you might see venting from an old v8 rocker cover. that aside, the engine runs great. 70psi oil and temp is good.

Could this be a coincidence? Could I have messed up the breather? Would a bad breather do this? I don’t mind throwing money at it if someone smart has a logical order for me to do so.
 
Last year I cleaned both of the Engine crankcase breathers in mineral spirits. I dried and reinstalled. Ever since then the port engine has only what I can describe as Blow by. Like you might see venting from an old v8 rocker cover. that aside, the engine runs great. 70psi oil and temp is good.

Could this be a coincidence? Could I have messed up the breather? Would a bad breather do this? I don’t mind throwing money at it if someone smart has a logical order for me to do so.

I just bought new ones this past year, they're pretty inexpensive as far as boat bucks go...
 
Last year I cleaned both of the Engine crankcase breathers in mineral spirits. I dried and reinstalled. Ever since then the port engine has only what I can describe as Blow by. Like you might see venting from an old v8 rocker cover. that aside, the engine runs great. 70psi oil and temp is good.

Could this be a coincidence? Could I have messed up the breather? Would a bad breather do this? I don’t mind throwing money at it if someone smart has a logical order for me to do so.

where are you seeing this blow by? Even if the engine had excessive blow by it should be firing back into the airsep and ingested into the engine. Or are you saying you see it when you pull it off the inlet on the airsep?
 
where are you seeing this blow by? Even if the engine had excessive blow by it should be firing back into the airsep and ingested into the engine. Or are you saying you see it when you pull it off the inlet on the airsep?
It is coming out of the small K&N filter just downstream from the breather. Prior to the airsep
 
Riptide, just a shot in the dark but the k and n filters have spring loaded black disc valves and should be at least 15 degrees above the horizontal if my memory is right, always a big if.
 
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Riptide, just a shot in the dark but the k and n filters have spring loaded black disc valves and should be at least 15 degrees above the horizontal if my memory is right, always a big if.
I am ordering new breathers today when the place opens. That part looks slightly different (less rounded) than mine. I am waiting to speak to their “parts specialist”. I will also adjust the other piece more vertical as suggested.
 
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Strange and nail-biting experience recently and could use some input as to where to start looking. Running at idle speed in heavy boat traffic coming into river and port engine just dies. 5 seconds later starboard engine dies. Drifting towards rocks I managed to get re-start the port engine but not the starboard. A couple of minutes later got the starboard engine re-started. All back to normal the rest of way back to dock? Gen. never stopped during the whole ordeal. Fuel filters? Each engine was running on separate tanks so fuel does not seem logical to me. Any thoughts would be greatly appreciated. Twin Cats 3116 TA.
 
Strange and nail-biting experience recently and could use some input as to where to start looking. Running at idle speed in heavy boat traffic coming into river and port engine just dies. 5 seconds later starboard engine dies. Drifting towards rocks I managed to get re-start the port engine but not the starboard. A couple of minutes later got the starboard engine re-started. All back to normal the rest of way back to dock? Gen. never stopped during the whole ordeal. Fuel filters? Each engine was running on separate tanks so fuel does not seem logical to me. Any thoughts would be greatly appreciated. Twin Cats 3116 TA.
Diesels need air and fuel... I would start with that. Filters are cheap. More experienced voices will jump in on this.
 
Strange and nail-biting experience recently and could use some input as to where to start looking. Running at idle speed in heavy boat traffic coming into river and port engine just dies. 5 seconds later starboard engine dies. Drifting towards rocks I managed to get re-start the port engine but not the starboard. A couple of minutes later got the starboard engine re-started. All back to normal the rest of way back to dock? Gen. never stopped during the whole ordeal. Fuel filters? Each engine was running on separate tanks so fuel does not seem logical to me. Any thoughts would be greatly appreciated. Twin Cats 3116 TA.

how did it run when it restarted? And they’re both running now?

start with both the racors and the secondary filters. I like to cut the secondaries and get a look at the element so see how gunked up they’re getting.

also check the primer pump handle to be sure it’s tightened properly. Those things can cause fits if they let air in
 
also check the primer pump handle to be sure it’s tightened properly. Those things can cause fits if they let air in
This and the air filters are separate from your generator which you stated ran fine. I have 3126 with the electrical box on each forward and I had to replace the 12volt relay on both.
 
Answers to a couple of responses. Before any of this happened, ran engines out in the lake for hour and half with no problems. The problem occured when returning to dock in the river at idle speed. Engines ran fine after restarting and all the way back to dock. No problems which leads me to believe what Bill Collector said about the electrical box and the relays. Another friend of mine with the same boat and 3126 cats experienced a similar problem with the electrical box recently. They are changing the fuel filters as I write this so will see what that yields when I get to the boat. Pump handle....will check that this weekend. Thanks guys for your replies and will update once I know anything.
 
I don’t think this is a fuel issue. The fuel issue would have shown its ugly head when your cats were guzzling fuel at cruise. Not much fuel getting used at idle speed. Sounds electrical, but weird that both engines were effected at almost the same time. I would not know where to start on this one. I will be watching and hopefully learning.
 

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