Do I need a new oil cooler?????

[Terry Kerr]

Shortly after I purchased my Luhrs Tournament 350 with twin 6 BTAs, Tony refered to the pics of my engine room as a “War Zone!”

Ever since I have spent at least ten times more hours working on my boat than using my boat. After coolers, SMX thermostats, puke bottles. She is coming along, but still has a long way to go.

Latest project was to replace the coolant pumps. I didn’t how old they were and wanted to be safe (raw water will be next). Ordered from SB arrived before the weekend and they were on by Sunday. Topped off both coolant reservoirs and took her out for a quick trial. all seemed well. A bit hotter than I was expecting with the new 160 degree thermostats, but still well under 200 degrees.

After she has cooled down I opened the caps to the reservoirs to check for coolant. The stbd was fine, the port engine had a huge amount of sludge floating at the top of the tank. I cleaned it out and the next trip same thing. I never noticed this before changing the coolant pump, but maybe I just never noticed.

I have removed the reservoir to better clean it in the garage.

A mechanic friend says it might be a bad oil cooler mixing oil with the coolant. My response was, ok let’s change it! Went to the SB site and can’t find them, so got to wondering, if this is something that goes bad then SB would have it for sale.

These engines only have about 2500 hours (unfortunately only about 150 hours from me in 5 years due to working on her). However, I think they were neglected.

I read on another string where Tony says to flush, flush, flush for 2-4 hours for neglected engines, but I already got the dang thing partial taken apart. LOL!

Is the flushing just for dark colored coolant or have sludge issues been a thing due to neglect as well?

 

Topic

[Clark Leighs]

Phone them OR Email them.

When you phone have the engine model number and serial number at hand.  They likely will need those to identify which engine so the right cooler is obtained. 

  Not everything is on any site.   I doubt oil coolers are a high replacement item unless they are seawater cooled. Even then a well built cooler may last 20+ yrs with only a seal replacement.  Many engines oil coolers are coolant cooled which require even less attention.  Not none of course.   Find out what you have.

[Terry Kerr]

Still thinking about changing the oil cooler

My Mechanic buddy is still pushing hard to change the oil cooler now that we have a bunch of stuff taken off anyway. 

He basically works for a seat on the boat during fishing trips, so if he is that gung-ho about doing it, I find it hard to argue.

They don’t appear to be overly expensive, when I pull them up on the web, but I’m pretty reluctant to buy from just anyone.

Can I get some help on where to look on this site? I can’t seem to find them and doing a search does not help.

He wants to change the turbo gaskets as well……

 

 

[Terry Kerr]

really great advice

Thanx so much!

Correct. No sign of overflowing oil or an empty dip stick.

Think I will clean really well (both motors) and see what happens.

Will keep the info on labs as with these poor motors I may need for later.

I have a lot of work to do, but this is the boat for me and therefore the motors for me.

I need to get them in shape and then keep them there.

 

[Clark Leighs]

I suggested the tests because you seem to have trouble deciding which way to go. A cooler will not be cheap.   THe tests will be far cheaper, expect about 30-35$ each.

Caterpillar SOS labs.     Sold by diesel repair shops all over the country.

Backstone   Labs  also.

 

Tony has  FAR more experience than I do or ever will do and I suspect he is right on.

Sludge can look like oil.

Just clean the engine using  a cleaner,  flushing and then proper antifreeze and change coolant every two years and it will continue to clean up.

 

[Tony Athens]

Past experience has shown this——–An engine oil cooler leak on these series of mid-range Cummins engines  is unforgiving and within a few  hours  of running,  the coolant system is over filled and the excess spills out thru the coolant cap into the overflow bottle– VERY OBVIOUS symptom.

From your posting,  I think you just have a filthy coolant system from a  decade or more of zero proper maintenance.

[Terry Kerr]

Great reply

I think having a lab test it might help put my mind at ease.

Ummmm I guess there are companies that do this?

[Clark Leighs]

Personally I would take and send in a sample of the contaminated coolant.    If it is oil the lab should be able to tell you.    If it is just accumulated sludge from neglect over a bunch of years they should be able to tell you that also.     But give a bit of an explanation of why you ask.    

If oil then you likely will need to pull and repair/reseal/replace the oil cooler.

If dirty with sludge then you may need to get a coolant system cleaner such as Cummins Restore and use it per directions.    Sludge is often rust from inadequate coolant attention AND/COOLANT BREAKDOWN.     All/MOST coolants have additives that if ignords will themselves breakdown and add to sludging.

As for the actual running temps.   The final running temp. is determined by the load the engine is under thus the fuel burned and the outside water temp the boat is running in.

The stat. opens  to provide the floor temps but does NOT guarantee the actual running temp will not climb higher.   

The final temp is determined by the engines cooling system condition and the outside water temp.    

 

My own personal experience of many years ago.  Our boat, current one, was 8 yr when we got her.   The first year I changed coolant.   I had to rod out every one of the drains which told me the coolant likely had not been changed in most of those 8 yr. if at all.  The rod was heavy guage copper wire.    Far to long.

I used Restore that first year and it helped but could not get all of the sludge as I realized the next change two yrs later.    However the rodding was much easier, a tie wrap .

Now many years later when I open the drain cocks the coolant runs IMMEDIATELY with virtually no dirt.        I have ever since used a 2 or 2.5 yr cycle and followed Cummins recommendations  ever since.     My engine needs DCA additive and gets it and I check it every  3-4 months.   You should not need the DCA though.

 

 

 

 

 

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