Service Costs CAT 3126

[Helipilot100]

Hi I have two of these beasts in my boat and was wanting a ballpark figure for servicing costs. I appreciate there are different levels of service but any indications to someone totally new to this would be great. Thanks

 

[Spare Thyme]

I have 2, do my own servicing using CAT parts from Finning, basic oil and fuel filters plus SOS testing works out at around £500, a lot depends on the engine hours as to what you need to do. I have a bunch of special tools for valve lash, but that only needs doing every 700 hours, very easy if you have the tools. Big warning make sure you use single grade oil, these engines do not like multi grade. There is a lot available on line at CAT re service details, if you can’t find pm me and I can send the service schedule. I am now 10 years on with these motors and prior to me there is another 10, total hours now 1500, 1250 of that I have put on and totally faultless, but they do like a bit of TLC, in summary
every year, oil and fuel filters plus clean and re oil the air filters ( check coolant and add CAT booster if required, test strips available at finning)
every 3 years replace the antifreeze, water pump impellers, transmission oil and engine anodes
every 5 years flush wit Radymine and check valve lash also replace belts
to be honest over the past 10 years the only Issue engine wise was a broken belt on the Mathers engine controls, I now carry spares ,

 

[rafiki_]

Spare Thyme is the guru. I had an Azi like his, and did most of the servicing myself too. Port engine impeller change is challenging due to its position. I had both water pump seals leak. Easy to fix once the pump is out for the impeller.

 

[Fire99]

Big warning make sure you use single grade oil, these engines do not like multi grade.

Just as a point of caution, this is only applicable for the 3126 MU (Mechanical Unit fuel injection). The later 3126B (which I have) and 3126E are HEUI engines and need multigrade (usually 15w40) oil.

 

[rafiki_]

The OP can check what oil etc is required by calling Finnings. They are the appointed Cat marine service company. Give them a call with your engine numbers and they will confirm the specification. Actually they are ok for spares prices, although eye watering for service charges. I sourced filters from a bus repair garage. These engines were pretty common in buses. I sourced oil from a local oil and fluids supplier. Finnings rebrand Exol 123 50 grade as Cat. I bought the Exol from the oils supplier. 25 litres per engine, about £60 for 25 litres. Probably more now.

 

[mil1194]

Finnings have always been great IMHO even though I have green lumps. I have a friend with twin 3208’s and Finnings have been full of the correct info.

 

[Boat2016]

The OP can check what oil etc is required by calling Finnings. They are the appointed Cat marine service company. Give them a call with your engine numbers and they will confirm the specification. Actually they are ok for spares prices, although eye watering for service charges. I sourced filters from a bus repair garage. These engines were pretty common in buses. I sourced oil from a local oil and fluids supplier. Finnings rebrand Exol 123 50 grade as Cat. I bought the Exol from the oils supplier. 25 litres per engine, about £60 for 25 litres. Probably more now.

I would be more inclined to buy all the parts from Finning if i call them for information, personally I would feel like I’m taking the p*** if i called them for information then bought elsewhere, no business is there just to provide free information.

 

[Fire99]

Are we not over complicating things a touch? And my dealings with Finning recently have improved but previously let's say I had a number of orders going pearshaped, including an order phone in with the part in my hand, gave engine numbers, serial numbers, even the part number of the item and they eventually sent me something completely different. They're not perfect.

There are two distinct and documented by CAT types of oil based on whether the engine has mechanical fuel injection or is a HEUI engine. It's pretty obvious which is which.

Mechanical Fuel Injection:
https://www.petersoncat.com/sites/cat/files/downloads/Cat SAEO.pdf

HEUI (3126B, E and C7 etc)
3116 and 3126 HEUI Truck Engines Lubricant Specifications | Caterpillar Engines Troubleshooting

With the HEUI, in European / UK waters 15w40 seems the norm, and my ownership/workshop manuals recommend..

 

[PowerYachtBlog]

If I remember these engines are also in need of a valve clearance at about 400 hours.

 

[Fire99]

If I remember these engines are also in need of a valve clearance at about 400 hours.

If it's the HEUI equipped B model like mine, valve lash is adjusted after first 200 hours and then again every 2000 hours..

That's from the Caterpillar Op and Maint. manual.

 

[Portofino]

The higher you go compression ratio wise like a diesel the more finely tuned or accurate the valve clearance needs to be , verging on pretty critical .
Not talking excess noise ( that’s subjective) talking power and efficiency a mirco second delay valve opening due to excess gap has on a CR 16 or 18 - 1 along with massive cylinder pressures compared to a petrol motor .

2000 hrs sounds a huge delay .400 is pretty normal and inho sensible.But no harm is doing it sooner rather than later .

Its easy DIY er able , or if you pay a guy I am sure you will recoup quickly it in better more efficient lower fuel burn .

 

[rafiki_]

If I remember these engines are also in need of a valve clearance at about 400 hours.

Correct.

 

[Fire99]

2000 hrs sounds a huge delay .400 is pretty normal and inho sensible.But no harm is doing it sooner rather than later .

I agree. I'm just stating what the Caterpillar maintenance manual instructs. I can only speak for the 3126B as it's the only 3126 i've encountered but other than slightly iffy ECM's they're really not very complicated engines and valve lash is pretty DIYable.. I'd schedule it in every couple of years based on average running time.

 

[Spare Thyme]

I have done the valve lash twice now, first time there was a lot of adjustment required, second time no adjustment needed, I suspect before I did it approx 500 hours, they had never been done. the setting block and gauge you need is widely available as it’s the same for the road engine, the digital dial gauge also available ( but it needs to be imperial threaded to fit the block), in addition to valve lash there is also the fuel rack to adjust, another bunch of special tools but I was advised byFinnings if they are running OK leave well alone, but do the valve lash every 400 hours, that’s about 5 years for me, you only have the fuel rack on the mechanical engine. The trick is to also get the TDC tool, it screws into the flywheel housing and makes finding TDC / BDC dead easy, you do half the valves at TDC, the spin the engine to BDC and do the other half, takes about 30 minutes per motor so no real hardship

 

[Portofino]

I use the “ rocker method “ Once you know the firing order easy to find online or manual and have a bar on the crank wheel and you are off .

Its the added efficiency I am after .The loosing the tapperty sound is second a happy second .
First time I did it @ 800 hrs thinking another 400 over the initial 400 , there were a few miles out hence the tapperty noise .I did notice I think more power and better fuel consumption numbers, smoother running .