Official Caterpillar3116/3126 Thread

[The Bill Collector]

Is everything that needs to be cooled (what is that list?) on the 3126 raw water versus coolant cooled? With the exception of the block of course.

https://www.dropbox.com/s/kpe6s3ky6n20g2u/3116-3126 OPERATION AND MAINTENANCE MANUAL.pdf?dl=0

 

[knotonduty]

Thank you for looking but I remember mine as looking very different, maybe those are used on bus or truck engines? Appreciate all your help.

said marine, dunno lot of different turbos for the 3126. I started with the 3116 cat number and went back from there.

 

[Maybe A Dancer]

Lots of folk have joined the AGM battery club:

WEST MARINE Group 27 Dual-Purpose AGM Battery, 92 Amp Hours | West Marine

For me, well I'm still doing low maintenance lead acid. I tag them with the install date, and when one hits 4 years, it gets replaced, regardless. The Trojan only runs 3, 2 group 27's and a 24 for the genny. Typically I buy them at WalMart - here's the specs:

EverStart Lead Acid Marine & RV Deep Cycle Battery, Group Size 27DC (12 Volt/750 MCA) - Walmart.com


West Marine Wally World Low Maint/Dual Purpose


900 MCA 750 MCA (marine cranking amps)


$310 x 5 = $1,550 $85 x 5 = $425

Just bought a 450DA, her West Marine AGM batteries are 5 years old. Two are weak, and in need of replacement. Surveyor recommends replacing them all.

20 years ago I tried the AGM route and was sorely disappointed.
I know there have been improvements since then but I just don't see the value.

Other than the MCA difference which shouldn’t be an issue here in warm Florida, what am I missing?

BEST !

RWS
EDIT #1: I should add that this boat currently has the original factory battery charger, which may be replaced at some future date with the BLUE SEAS model with the remote panel which I LOVED on my 10 Meter.

EDIT #2: Has anyone successfully installed BCI Group 31 in a 450 DA?

RWS

BUMP

 

[ttmott]

Without pulling it off completely. Could I pour a descalong solution in the upturned coupling hose and collect it on the other side?

It's definitely dirty. I would like to see how it tracts with just a clean, before I remove it and take it in.

I'm sure that would work also.

 

[Thomas Griffith]

I'm sure that would work also.

So that did seem to give us some added flow, but not significant enough to be the game changer. It's been descaled pretty well over the last day.

One thing i failed to mention in previous posts (always something) we noticed that the flow on starboard is only about 1/3 difference from port. However the air exhaust through the underwater exhaust is significantly reduced on starboard relative to port. I'm taking the air filter off today and just going to see what happens with no filter on for a moment.

Any other thoughts as to why the exhaust may be restricted. The surveyor pressure tested the exhaust elbows and said it tested well.

 

[Strecker25]

So that did seem to give us some added flow, but not significant enough to be the game changer. It's been descaled pretty well over the last day.

One thing i failed to mention in previous posts (always something) we noticed that the flow on starboard is only about 1/3 difference from port. However the air exhaust through the underwater exhaust is significantly reduced on starboard relative to port. I'm taking the air filter off today and just going to see what happens with no filter on for a moment.

Any other thoughts as to why the exhaust may be restricted. The surveyor pressure tested the exhaust elbows and said it tested well.

Do you mean just less bubbles on one side vs the other? Our 410 is the same, I get bubbling at an early rpm on the port side versus the starboard. I’ve never investigated it but the two engines are plumbed completely different and I figured that had something to do with jt

 

[Thomas Griffith]

Do you mean just less bubbles on one side vs the other? Our 410 is the same, I get bubbling at an early rpm on the port side versus the starboard. I’ve never investigated it but the two engines are plumbed completely different and I figured that had something to do with jt

Exactly that. The starboard side has only a tiny amount of bubbles intermittently at 750ish rpms. The port side is a geyser at the same rpm. I've got the filter drying in the sun on the back deck. I also ran some descaling solution in my Aftercooler this morning, was already doing the AirCon strainer so figured i'd do both at the same time.

The PO's Maintenance Contract guy said he descaled the engine multiple times this summer and replaced the impeller. The impeller was oversized, the zincs were never replaced, and while the HEX was very clean, the gear cooler was not at all clean. Between that and the household wire nuts he used to replace the AirCon pump, I don't think we will be allowing him anywhere near our boat. Self Maintenance is the key i've learned!!!

 

[Strecker25]

Exactly that. The starboard side has only a tiny amount of bubbles intermittently at 750ish rpms. The port side is a geyser at the same rpm. I've got the filter drying in the sun on the back deck. I also ran some descaling solution in my Aftercooler this morning, was already doing the AirCon strainer so figured i'd do both at the same time.

The PO's Maintenance Contract guy said he descaled the engine multiple times this summer and replaced the impeller. The impeller was oversized, the zincs were never replaced, and while the HEX was very clean, the gear cooler was not at all clean. Between that and the household wire nuts he used to replace the AirCon pump, I don't think we will be allowing him anywhere near our boat. Self Maintenance is the key i've learned!!!

it certainly can’t hurt to clean the filter but that would be a serious restriction on the intake side. How dirty did it seem before you cleaned it?

either way it’s good practice. I clean and oil ours once a year since it’s easy and cheap

 

[Thomas Griffith]

it certainly can’t hurt to clean the filter but that would be a serious restriction on the intake side. How dirty did it seem before you cleaned it?

either way it’s good practice. I clean and oil ours once a year since it’s easy and cheap

It was pretty dirty. But I turned the motor on with it off and didn't see anything change. When you run your, at what RPM does the starboard side match the port side?

 

[ttmott]

I wanted to clarify, I was in neutral at 1900+ rpms at the dock when it went up. It doesn't overheat at -1600rpms under load or in neutral.

I just switched out the impeller today. The old one from the previous owner appeared to be larger vanes than the new one from Caterpillar. That being said, it still got to 190 running at 1900+ rpms in neutral. And the water flow on the starboard side is still noticably less than on the port at the same 750ish rpms.

My diver is going to check and see if the ball valve on the seacock is off kilter this coming week. However I opened both strainers and opened the seacocks and appeared to get comparable gushes.

Coolant side flushed
HEX cleaned and free of debris
New impeller from Cat
Fresh coolant, CAT ELC
New 190 degree thermostat from Cat
Checked and tightened Hose Clamps

Any other ideas??

Here is a couple of things you might not have considered -
The engine coolant loop may be the culprit -

• Cat ELC will form a layer of, call it, slime on the engine and Hx internal surfaces which is actually a thermal barrier. Flushing and replacing the coolant will correct this. Use the Cat Flush.
• The coolant pump is driven by a belt which needs to be replaced and tensioned routinely. If it slips the cooling capacity will be reduced.
• The cooling system thermostat is a maintenance item and should be changed every time the coolers are serviced; around every 5 years.
• The rubber hoses in the cooling loop become soft over time and can collapse so also they need to be changed per the maintenance schedule.
• If the cooling system cannot pressurize it's thermal transfer capability is reduced; replace the expansion tank cap to ensure the correct pressure can be obtained.

 

[Thomas Griffith]

Here is a couple of things you might not have considered -
The engine coolant loop may be the culprit -

• Cat ELC will form a layer of, call it, slime on the engine and Hx internal surfaces which is actually a thermal barrier. Flushing and replacing the coolant will correct this. Use the Cat Flush.
• The coolant pump is driven by a belt which needs to be replaced and tensioned routinely. If it slips the cooling capacity will be reduced.
• The cooling system thermostat is a maintenance item and should be changed every time the coolers are serviced; around every 5 years.
• The rubber hoses in the cooling loop become soft over time and can collapse so also they need to be changed per the maintenance schedule.
• If the cooling system cannot pressurize it's thermal transfer capability is reduced; replace the expansion tank cap to ensure the correct pressure can be obtained.

The only thing on that list is replace the coolant hoses, however they've been checked when it's running to make sure there is no collapsing. After I refresh the aftercooler, the hoses are my next step.

I'm going to laugh if it turned out it's my ball valve not opening all the way, ill find that out this week hopefully.

 

[Strecker25]

It was pretty dirty. But I turned the motor on with it off and didn't see anything change. When you run your, at what RPM does the starboard side match the port side?

starboard starts to bubble under the boat about 1400-1500 rpm

 

[Thomas Griffith]

starboard starts to bubble under the boat about 1400-1500 rpm

What!! That's wild. Well I suppose I'll stop chasing that ghost then!

Yesterday I ran the starboard in neutral at 2000-2300rpms and it did not cross 190. That's the first time it has stayed at 190 or below. Doing some more descaling and then taking it out later this afternoon to test it out under load.

 

[ttmott]

What!! That's wild. Well I suppose I'll stop chasing that ghost then!

Yesterday I ran the starboard in neutral at 2000-2300rpms and it did not cross 190. That's the first time it has stayed at 190 or below. Doing some more descaling and then taking it out later this afternoon to test it out under load.

Diesel engines do not build heat unless they are loaded. Work is heat right?

 

[Thomas Griffith]

Diesel engines do not build heat unless they are loaded. Work is heat right?

Not sure what you mean. Running 2300+rpm is going to add heat to the mix, regardless of its in gear or not.

 

[ttmott]

Not sure what you mean. Running 2300+rpm is going to add heat to the mix, regardless of its in gear or not.

Not really, the engine is going to fuel itself based upon load not necessarily throttle position and/or RPM. It is the quantity of fuel being burned over time that makes the heat. The injector rack is positioned by a relationship of RPM, throttle position and manifold pressure.

 

[Strecker25]

Yep, no load means it’s basically just a big freewheeling air pump. We build 1psi of boost at 2400 no load and 17-20psi under load so that gives an idea of how much more pressure and fuel it takes to run them

 

[ttmott]

Not really, the engine is going to fuel itself based upon load not necessarily throttle position and/or RPM. It is the quantity of fuel being burned over time that makes the heat. The injector rack is positioned by a relationship of RPM, throttle position and manifold pressure.

As an edit - setting the throttle out of gear to achieve 2300 RPM the engine will only provide enough fuel to increase the RPM (no work being done); the turbocharger is not getting heat to spool up so no boost being built, and the governor is saying - I have a higher throttle position and RPM's are higher so I don't need to add any more fuel. If on the other hand the throttle position is higher and RPM's are low the governor says I need to add more fuel to get the RPM's up and because of that the turbocharger is getting the thermal energy to spin up and make boost which the governor now says I can even add more fuel to get to my target throttle setting.

 

[Maybe A Dancer]

As an edit - setting the throttle out of gear to achieve 2300 RPM the engine will only provide enough fuel to increase the RPM (no work being done); the turbocharger is not getting heat to spool up so no boost being built, and the governor is saying - I have a higher throttle position and RPM's are higher so I don't need to add any more fuel. If on the other hand the throttle position is higher and RPM's are low the governor says I need to add more fuel to get the RPM's up and because of that the turbocharger is getting the thermal energy to spin up and make boost which the governor now says I can even add more fuel to get to my target throttle setting.

======

well said

 

[Thomas Griffith]

As an edit - setting the throttle out of gear to achieve 2300 RPM the engine will only provide enough fuel to increase the RPM (no work being done); the turbocharger is not getting heat to spool up so no boost being built, and the governor is saying - I have a higher throttle position and RPM's are higher so I don't need to add any more fuel. If on the other hand the throttle position is higher and RPM's are low the governor says I need to add more fuel to get the RPM's up and because of that the turbocharger is getting the thermal energy to spin up and make boost which the governor now says I can even add more fuel to get to my target throttle setting.

So we took it out to load test it. I found 3 coolant leaks in a section our now fired mechanic replaced the housing regulator that be busted the flange off of and the hoses should've been replaced. Got new hoses now.

Is there a bleeder valve somewhere on the coolant circuit?