Oil Change Guidance - 2004 Mainship 400 single Catapiller 3126

[Bay Retriever]

Just a quick ask - has anyone changed the oil themselves on a boat like mine? If so, please send any tips for the job and any other suggested items to complete at the same time.

Many thanks in advance

T MacDonnell
Bay Retriever
2004 Mainship 400

 

[psneeld]

One thing if I remember about the 3126 is that CAT suggested specific oil and antifreeze.


Could have been the 3116 but I think it was the 3126.


Be careful to take generic oil suggestions...I suggest you read a CAT web site on the 3126 or call a CAT dealer.

 

[garmstro55]

Just a quick ask - has anyone changed the oil themselves on a boat like mine? If so, please send any tips for the job and any other suggested items to complete at the same time.

Many thanks in advance

T MacDonnell
Bay Retriever
2004 Mainship 400

Tom, first check to see if you have the oil X-Changer device. It would be in the lazarette adjacent to the generator on the wall. That makes it a piece of cake, unless you have the same problems and me and Rich Gano had and the impeller failed. I had to replace mine this year.

I can't comment on the oil change for a Cat, but I'm sure others will. Perhaps you can suck the oil out through the dipstick hole using one of the marine oil change devices. I would do that with my Crusaders on my Silverton.

 

[High Wire]

3116s need straight sae 30 due to closed crankcase ventilation. 3126 are slightly different. It’s one of those asterisk notes on the oil bulletin.

 

[High Wire]

As always check for the latest guidance from CAT:
Here is an old part of it:
Engine Oil (3116 and 3126
Marine Engines)
SMCS Code:
1348; 7581
Recommendations
Cat does not recommend the use of multigrade oils
in the 3116 and 3126 Marine Diesel Engines that use
mechanical unit injection (MUI).
Multigrade oils use high molecular weight polymers
as viscosity index improvers. When the crankcase
blowby flows through the turbocharger and the
aftercooler, the viscosity index improvers can adhere
to the turbocharger compressor and aftercooler core.
The fouling of the turbocharger and aftercooler can
cause reduced air flow, loss of power, and increased
black smoke. The emission of black smoke results in
buildup of soot on the transom of the boat.
Note:
Cat recommends the use of single grade oils
that pass all API CF-4 category requirements unless
crankcase blowby has been routed away from the
air cleaner inlet.
Cat SAEO (Special Application Engine Oil)
Note:
Cat SAEO is recommended for use in Cat 3116
and 3126 Marine Diesel Engines with mechanical
unit injection. 3116 and 3126 Marine Diesel Engines
that begin with the following serial number prefixes
are included: (S/N: 6SR), (S/N: 8NM), (S/N: 4KG),
(S/N: 1SK), (S/N: 1ZJ), (S/N: 6MK), and (S/N: 4EZ).
The factory-fill for 3116 and 3126 Marine Engines is
Cat SAEO with the following properties:
•
Meets all requirements of API CF-4 category
•
Viscosity grade of SAE 30
For maximum performance in 3116 and 3126 Marine
Diesel Engines with mechanical unit injection, Cat
recommends the following engine oil:
•
Cat SAEO (SAE 30)
•
Cat SAEO (SAE 40)


Commercial Oils (3116 and 3126
Marine Engines)
NOTICE
Cat does not warrant the quality or performance of
non-Cat fluids.
When Cat SAEO is not used, use the following
commercial oils:
•
Single grade oil with a viscosity of SAE 30 or SAE
40 that meets all API CF category requirements
is preferred.
•
Single grade oil with a viscosity of SAE 30 or
SAE40 with an API CF additive package and no
viscosity improvers is acceptable oil.

 

[fgarriso]

I just fill the new oil tank, and make sure the waste oil tank is empty. Then to change the oil I flip the switch to PUMP OUT, and then to REFILL until the dipstick reads full .

 

[Pmcsurf1]

https://youtu.be/hdDIoXZOhNE
Just did mine. Yanmar not Cat but similar id bet. Oil and fuel filters.

 

[Lepke]

All the engines in my boats have been had their pan drain plumbed to a pump and then to a tank that can be pumped out at a fuel dock or sent to a centrifuge. If necessary I relocate the filter so it can be changed w/o making a mess.
Open some valves, turn on the pump, pop off the filters, and I can do 2 Detroits and 2 generators in less than 30 minutes.

 

[Njlarry]

As already pointed out....use only straight 30 or 40 wt oil and do not prefill the filter. Also only use CAT brand filters, they are very differently made. Lots of info on you tube and in CAT manuels you can find on line. Be glad you only have one monster 3126 to feed.

 

[Lepke]

Engines experience the most wear at startup. That's why industrial diesel users (including Cat users) have oil accumulators that release pressurized oil at start up. Running an engine without oil pressure when starting on the theory that new oil is too dirty to run defies logic. Whatever lubrication new unfiltered oil provides is 100% better than lubrication provided by no oil.
Maybe this is one of the reasons I get many more hours out of an engine rebuild than other people using the same engines.

 

[Njlarry]

Capt. Lepke you are far more knowledgable and experienced than I will ever be but on this one issue I must respectfully question. CAT engineers should know their engines. The manual clearly states in bold type on page 85 not to prefill the filter. As Adept Ape, the you tube CAT expert, points out they even print on the filters not to prefill. He states there is plenty of old oil still in the galleries and bearings so he only would prefill a brand new rebuild. As he and others point out, if a person does want to prefill, they should plug the center hole and fill the outer holes.

 

[Seevee]

I had the exact same boat, but with the Yanmar.


The video is fine for the basic concept, and would suspect it could be applied to any engine. I'd be there's an OilOMatic or some electric pump to pump out the oil, and most likely connects to the generator, too. If using one, be SURE the oil is coming from where you want it to, and going to the drain line.


A few comments on the video. First, you do not need to remove all the hatches. I've rarely had the port one off, certainly not for basic maintenance including oil and filter changes, battery service, even removal of the heat exchanger, alternator and/or belt, etc. etc. The guy in the video has WAY TOO much crap in his boat. Geesh! Clean it up.



Also, make those support bars for the hatches quick removable. Makes the maintenance on that boat SIGNIFICANTLY easier.



Now, without the electric oil pump out, one can get that manual pump in the video, but do it when the oil is warm, but will still take a LONG time thru the oil dip stick tube.

 

[High Wire]

3116/3126s hold about 7 gallons of lube oil. Trying to suck it out the dipstick will take a while.

 

[costalive]

What type of oil accumulator do you use

Engines experience the most wear at startup. That's why industrial diesel users (including Cat users) have oil accumulators that release pressurized oil at start up. Running an engine without oil pressure when starting on the theory that new oil is too dirty to run defies logic. Whatever lubrication new unfiltered oil provides is 100% better than lubrication provided by no oil.
Maybe this is one of the reasons I get many more hours out of an engine rebuild than other people using the same engines.

I totally agree with you and surprized I have never see them installed on a boat yet.
I have been studying the accumulator tank type pre oiler and also the electric motor type pre oiler they use on airplanes.
I am curious what type of accumulator do you run on your 6 71’s and what would you suggest for 12v 71N?

 

[Hawkshaw1]

Oil

I have a CAT 3126 in my 390.

CAT no longer produces the special oil and now recommends their regular diesel. Call your dealer.

 

[Simi 60]

I have a CAT 3126 in my 390.

CAT no longer produces the special oil and now recommends their regular diesel. Call your dealer.

Say what?
Cat produced "special" oil?

 

[Hawkshaw1]

Say what?
Cat produced "special" oil?

Yes, specifically for the 3126. The oil was discontinued last year.

 

[Njlarry]

There are long discussions on this at boatdiesel.com and clubsearay.com.
Bottom line is most all including myself contiue to use only single wt oil which CAT recommended for decades till they stopped selling it. Dealers may sell you on multi wt but will they replace your aftercoolers?

 

[Simi 60]

Yes, specifically for the 3126. The oil was discontinued last year.

I doubt they produced it
Surely they simply re badged someone else's product