Changing single oil cooler to duel

[Brock]

I gotta say, I agree with Rawze on this one.... Even a 600 shouldn't have that issue. You've got something wrong. Are you lugging the engine while climbing hills? How much weight do you haul and what rpm do you shift at?

[HankAz]

Well just going up Baker grade it was about 105 out truck was empty and I was not pushing it. Water temp was around 200.

[Brock]

What rpm are you climbing at? climbing a grade empty or not below 1400 is going to cause heat.

[HankAz]

About 15-1600its an auto shift it don't get lugged down.

[Diesel Deacon]

You will find engine brake determines 1 or 2 coolers. If you have 3 soleniods for engine brake,2 coolers

[Rawze]

(02-15-2020 )Diesel Deacon Wrote:  You will find engine brake determines 1 or 2 coolers. If you have 3 soleniods for engine brake,2 coolers

That is not so much the case?. I have seen engines with dual elements, and they all had only 2 engine brake solenoids.

[Signature620]

Most highway trucks in Australia run at around 64T (140,000lb) and I haven't seen a new 600hp engine with dual coolers since the cm570 was phased out.

It sounds like you had a bad oil thermostat and you've fixed it.

If it's not a bad oil t/stat it's usually a coolant temp issue or overly advanced timing in a poorly deleted ECM file.

Also remember, the coolant cools the oil - So once everything is at running temp and under load, oil will always be warmer than coolant. They shut down at 125 Celsius/ 257 Fahrenheit.

[Rawze]

(02-15-2020 )Signature620 Wrote:  ... I haven't seen a new 600hp engine with dual coolers since the cm570 was phased out.
..

thanks for the info. Makes a lot of sense, and your info about bad programming or other things is spot on too.

rule of thumb on the ISX is that the oil temp should be ~40 degrees(F) above the coolant temp or less. Otherwise the oil cooler is not keeping up (for the various reasons you stated) or there is an oil cooling thermostat or other problem somewhere.

I have actually seen (2 or 3 maybe) 871's with dual elements actually on them, though it is not common. The last one I saw, I noticed it also had a (factory installed) much larger 3-piston (might have been 4-piston) air compressor on it too, but I would not associate the two things as always being associated together. - maybe there are some customer-spec/requested builds running around out there?. I remember looking up the engine ser#, curious about the larger air compressor, and seeing both the dual element coolers and the larger air compressor in the spec sheet on quickserv for it as well.

-- It could perhaps be that some of these engines are sometimes spec'd somewhere, by someone before purchase specifically for a lot of low-rpm high torque PTO?. - That would explain the bigger volume compressor and extra element as the coolant and oil flow would need extra cooling if the engine was under high stress but also rpm moving a much lower overall volume of oil and coolant?- (Speculation). This particular engine was a 535 if memory serves me right, so the dual elements installed were not really justified otherwise.

just sharing some additional thoughts, may not be the case.

I have not seen factory duel elements on a 2250 or 2350 yet tho, but that certainly does not mean none can exist.

[Signature620]

There was a run of recon ISXs about 2-3yrs ago that were fitted with incorrect single cores. The element was too shallow and these engines experienced high oil temps. I can't find a bulletin for it, I think it may have been an internal engineering bulletin as most of the engines were reworked with the full sized single core at the warehouse before they were delivered to OEMs.