Official Caterpillar3116/3126 Thread

As I recall, the 3196's had a number of upgraded aftercoolers recommended for replacement. As @ttmott stated, no other models required aftercooler replacement due to design deficiency. The 3196 became the C12 as I recall. And that is the final aftercooler replacement - "as I recall"...
 
If I’m not running hot. Should I just flush them. Or should I remove them and bring them to shop to have them boiled out abd tested.
 
Tom,

I am not sure about Cats recommendations on the 3126, since I had 3116's.

3116's were jacket cooled not seawater cooled like the 3126 so I had no risk or saltwater corrosion in the aftercoolers. Fouling from multiviscosity additive break down was the animal we addressed and the aftercooler cleaning interval was every 1000 hours.

That said, it only makes since that the 3126 be cleaned on the same schedule since the air side suffers from the same fouling risk as the 3116.


Frank
 
A friend just had a survey and oil samples completed on 2003 3126’s and was shown high iron (33ppm) and high aluminum (6-8ppm)

the iron seems barely outside the normal range so that didn’t bother me but our samples show zero aluminum. What in these engines would wear aluminum and deposit in the oil? I suggested a blow by test at minimum but just in the general health sense, not sure it will show what might be causing Al wear

the engines have 5 years of oil samples with constant Fe readings in the teens and this year increased to 33. Al has been zero for 5 years so this years sample was the first to show a trace
 
A friend just had a survey and oil samples completed on 2003 3126’s and was shown high iron (33ppm) and high aluminum (6-8ppm)

the iron seems barely outside the normal range so that didn’t bother me but our samples show zero aluminum. What in these engines would wear aluminum and deposit in the oil? I suggested a blow by test at minimum but just in the general health sense, not sure it will show what might be causing Al wear
Pistons. If there is a spike from previous samples look to see if there is an injector problem that is washing down the cylinders. If chromium was high then piston rings could be suspect and I'd consider a blow-by test. Did they test for elevated fuel in the oil?
 
I wouldn't worry too much about the iron however iron will go up as a result of fuel dilution. The gears are not getting the quality lube they need and their wear is elevated.
 
Thanks guys, I’ll let them know. Definitely need to do a blow by test but I’ll ask if they tested for fuel in the oil and what the chromium was.

side note, are the 3100’s steel topped aluminum pistons?
 
Thanks guys, I’ll let them know. Definitely need to do a blow by test but I’ll ask if they tested for fuel in the oil and what the chromium was.

side note, are the 3100’s steel topped aluminum pistons?
Pretty much all diesel engines are all aluminum alloy pistons these days. Pretty much all diesels also have oil cooling sprays under the pistons also these days....
 
Pretty much all diesel engines are all aluminum alloy pistons these days. Pretty much all diesels also have oil cooling sprays under the pistons also these days....

interesting. Maybe I should buy a spare and take it all apart to really understand our engine :)
 
Chromu
Pistons. If there is a spike from previous samples look to see if there is an injector problem that is washing down the cylinders. If chromium was high then piston rings could be suspect and I'd consider a blow-by test. Did they test for elevated fuel in the oil?

Chromium rose from 0 to 3ppm
 
So, Chromium can come from roller bearings, rocker arm shaft plating, and piston rings; not many more things in these engines have chromium.
We have elevated iron (gears or cylinder liners), spike in aluminum (pistons), and elevated chromium. Yes I'd do a blow down test on all cylinders and look for problems in the fueling system (elevated fuel in the oil)....

However, if fuel is high in the oil then maybe just change the oil fix the problem with the fuel system and run it then check the oil again in 50 or 100 hours. Maybe not yet get carried away with expensive witch hunting.
 
So, Chromium can come from roller bearings, rocker arm shaft plating, and piston rings; not many more things in these engines have chromium.
We have elevated iron (gears or cylinder liners), spike in aluminum (pistons), and elevated chromium. Yes I'd do a blow down test on all cylinders and look for problems in the fueling system (elevated fuel in the oil)....

However, if fuel is high in the oil then maybe just change the oil fix the problem with the fuel system and run it then check the oil again in 50 or 100 hours. Maybe not yet get carried away with expensive witch hunting.

the current owner said he only ran the boat at idle/barely above idle, for the last few years to go from his home dock to a club. Very rarely on plane. Overfueling with the excess idle time and cylinder washdown causing a bit of wear?

seems like blow by test is a necessity for them.
 
the current owner said he only ran the boat at idle/barely above idle, for the last few years to go from his home dock to a club. Very rarely on plane. Overfueling with the excess idle time and cylinder washdown causing a bit of wear?

seems like blow by test is a necessity for them.
Then I'd do a blowby test on both engines so there was comparative data.
 
I probably should have just kept watching the Eagles Concert on DirecTV……….Tom has likely already solved this one.

Here is a very good reason to use Cat's SOS oil analysis system. They check every oil sample for both fuel and coolant in the oil.

Given the presence of excess aluminum, high chromium and high iron I think Tom hit the nail on the head…….a washed out cylinder where unburned diesel fuel has washed the lube oil off the cylinder walls and the aluminum is from piston skirt wear, chromium is from piston ring wear and high iron is from the cylinder wall wear. This can probably be confirmed by checking for fuel in the lube oil sample. This means there is some urgency in solving the high metals problem because it will only get worse and more expensive from here. The cause could be as simple as a carbon fouled injector tip that just need cleaning or replacing.
 
I probably should have just kept watching the Eagles Concert on DirecTV……….Tom has likely already solved this one.

Here is a very good reason to use Cat's SOS oil analysis system. They check every oil sample for both fuel and coolant in the oil.

Given the presence of excess aluminum, high chromium and high iron I think Tom hit the nail on the head…….a washed out cylinder where unburned diesel fuel has washed the lube oil off the cylinder walls and the aluminum is from piston skirt wear, chromium is from piston ring wear and high iron is from the cylinder wall wear. This can probably be confirmed by checking for fuel in the lube oil sample. This means there is some urgency in solving the high metals problem because it will only get worse and more expensive from here. The cause could be as simple as a carbon fouled injector tip that just need cleaning or replacing.

it was the SOS from HO Penn, I just got the sample report and you guys hit it, PFC has increased over the last samples: .39, .40, .47, and then 1.00 on the most recent.

what I don’t know is if 1.00 is significant fuel dilution?

oh and here’s the other kicker, this sample and the last year only had 15 hours total runtime and that was for the entire season.
 
Last edited:
1. Get your Cat dealer to evaluate the condition of the injectors then do a blow-by test on both engines.
2. Stop running around at idle speed. Cat engines like to run, they do not like this putting around. Try to get the engines up to 1400–1500 rpm or where you can hear the turbos begin to spool up. The goal is to get the engines where they are under enough load to begin to work so any excess fuel is burned.
3. Consider selling the boat and buy a Porsche to drive over to the yacht club. Under the present useage, the Porsche will cost less and impress about an many friends.


Good luck with it…………...
 
1. Get your Cat dealer to evaluate the condition of the injectors then do a blow-by test on both engines.
2. Stop running around at idle speed. Cat engines like to run, they do not like this putting around. Try to get the engines up to 1400–1500 rpm or where you can hear the turbos begin to spool up. The goal is to get the engines where they are under enough load to begin to work so any excess fuel is burned.
3. Consider selling the boat and buy a Porsche to drive over to the yacht club. Under the present useage, the Porsche will cost less and impress about an many friends.


Good luck with it…………...

haha for sure! I told them the same thing, that’s quite the water taxi.

my advice to them is to get CAT to come out and run the PAR. It’s $2800 for both engines and maybe since they’ve found some potential issues they can get the sellers to split the bill.

Any idea what acceptable PFC is? Out of curiosity I checked our report and we have 1.8 on both engines and no issues or other wear metals or contamination noted.
 
I have 20 years of SOS reports on my 3116's and everyone has water and fuel contamination reported as "N" which is none. Just for reference sake, the last SOS was done with 150 hours and 1 year on the oil, but total time of 1550 hours on the engines and the contaminents were

Chromium 0 ppm
Aluminum 1 ppm
Iron 4 ppm

All were within normal limits, according to Thompson Caterpillar in Nashville TN

Since I've never had a report come back with anything but "No" fuel dilution, I've had to do some homework on that,

Fuel contamination is measured and reported as a % of volume. So an engine with a 26 qt. oil capacity with 1.0% fuel dilution means the engine is holding roughly a 8oz glass full of fuel when it should have <.2% fuel contamination. So, my view is that a 1% fuel dilution isn't the end of the world, but coupled with abnormally high Fe, AL and Cr, it is indicative of a cylinder wash out that can get very expensive, and in the worst case, end up in a top end overhaul which on a 400/410 or 380DA (guessing) means removing the cockpit deck and the offending engine then boring the engine and sleeving the cylinders and buying a new set of pistons and rings.

The low run time but all done at idle could be the cause of the problem if one or more cylinders was not completely burning its fuel charge. To determine that may take removing the injectors and having their spray pattern tested on a test stand. That would requires resetting the overheads when the injectors are reinstalled.

The more I think about this the more complicated the route to the finish line becomes.


Frank
 

Forum statistics

Threads
112,945
Messages
1,422,746
Members
60,928
Latest member
rkaleda
Back
Top