Machine has been creeping up in temp when working under load. No bubbles in tank, replaced the themostat and flushed the rad but still gets hot. When pouring water into the rad it seems to take a long while to trickle down. A new core is $3.5K plus fitting. Any ideas on cause and what methods are best to try and clear the score within removing it.
Have read that some people use vinegar to clean out a cooling system but don't know if it's advisable on a newer Cat.
Start with the basics. Pulleys and fan belts in good order, radiator clean externally, and, on these models no exhaust leaks. What did you do to flush the radiator?
Exhaust belts etc good. Used Techaloy heavy duty and followed all instructions,
I think I gave around 1500 for a cat classic around three years ago. This machine has always run hot, just put a complete rebuild in it last year and still run hot. Come to find out the new thermostat was bad. It still heats on warm days just not as bad. Around 210 or so, before it would bury the gauge. I also put a mechanical gauge in place of the factory gauge. Seems to be a lot more accurate. When I had the motor out I put a piece of strap metel welded to the outside edge wire cage around the fan. Before this it had a lot of air blowing back around the edge of the blades.Still needing to pull the rear guard and plug all the air leaks going around the radiator and cooler. Also took the thermostat housing and drilled the top out to full diameter. They have a lot of restriction. I wish when we put a new radiator in I would have gotten as big of one as could be had. The classic has less cores than the original.
I might be off base here, but have you confirmed the temperature with a IR or other type thermometer? Just trying to avoid someone chasing "ghosts"! I always like a second opinion on any reading. Are other temperatures also creeping up? Like transmission or hydraulics? Just thinking that a problem with excess heat some place else could be putting more demand on the engine's cooling system. Same operator and working conditions? You say "When pouring water into the rad it seems to take a long while to trickle down." Is this something new or did you not have reason to observe it before?
Getting the radiator out and to a competent reman shop for a thorough Internal cleaning is indicated. Don't need a 'New' one, just take the downtime to get this one rodded. Chemicals will only go so far, physical agitation is a due course need.
I had the same thing happen on a 953. Pressure washing the core on the outside, fixing exhaust leaks dropped the temperature 25*s It will not even get close to 210 now. It really didn't look dirty but you keep spraying it till the water that comes through that radiator is clean and you can see like through it. It took me 2 hours and yep I got soaked.
When you check the temps, check the top and bottom of the radiator, and the air on both sides of the radiator. That will tell you most of what you need to know about the radiator. If it does end up plugged internally, because you can see the tops of the tubes plugged, or because the temp drop is too high from top to bottom, or because you know it's had swamp water added repeatedly, then I've had good luck backflushing radiators with and air gun stuck in the bottom and the top hose and cap off. Stick a running garden hose in the top, when it overflows hit it with air, repeat there's no more sediment. Or let it freeze then backflush.