3406 high coolant temps

Take the front neck off and the 4 bolts thst hold the rear to the block. Flush it with water and watch the other end to make sure all tubes are flowing a full pipe

 

More then likely it will be plugged at the end closest to the rear of engine. The front end closest to water pump is suction. The rear is pressure.

 

...And they ain't all that expensive...

NEW OIL COOLER FITS 3406B 3406C 3406E 7C3039 CATERPILLAR ENGINES NO CORE | eBay

 

buy yourself an aftermarket one with the copper sealing on the rubber. it will stop the rubber breaking apart over time. IPD do a great one well priced.

 

Inside of hoses deteriorating....one thought. Could be clogging up your radiator tubes, but I thought I read a bit back that you replaced the radiator? That could also be a culprit in clogging your oil cooler tubes too.....

 

Yeah, it's sounding more and more like an oil cooler flow issue now more than anything. That's the only thing left to do in the coolant flow department the way it sounds.

I was talking to my Cat guru about this last week. He's got my 3406B at his place doing rods and mains, harmonic balancer, front seal and a Jake brake that I've had on the shelf for a year now, always wanting to put it on the PCTA motor but now I'm glad I didn't. We got on the subject of timing. I said how I gave a guy a perfect injection pump off of a blown 3406B that I had parted out a couple years ago and now I wished I'd have kept it for a backup. He surprised me by saying "most likely it wouldn't have worked anyway, all it would have done is screw up the timing and run hot"...that reminded me of your deal.

He said (and of course it's a fact,) that you can't just go throwing any old injection pump off another engine onto the one you're running just because it's yellow. They have to match certain numbers and codes together to be compatible, and a lot of guys do it and end up in trouble. They don't do their due diligence and homework, end up with a meltdown.

I learned something new yesterday after talking to him again. My boy drives a Pete triaxle dump truck with a C-15 Acert twin turbo 475 hp. Yesterday he heard a strange noise like he ran over a piece of metal or something. Moments later, he said the pyrometer was running at 800 degrees empty going down the road and lacked power, so he swung into the shop where I'm working on my truck and had me and my buddy listen to it. All 3 of us agreed that top turbo sounded strange, so the owner of the truck who was present also had us pull it apart and get it figured out.

The subject arose about converting the engine over to a single turbo instead of the twins, as they sell a kit to do so. Two turbo's are around $5,000.00, and the conversion kit to single it out is around $7,000.00. The owner thought it'd be the right thing monetarily, but I had my reservations so I called my "guru" and ran it by him. He said "absolutely NOT, the single turbo conversion kits do NOT work".

Puzzled with that answer, I asked why. He continued to say that people do it all the time and then wonder why the engine has no power after, lag, low boost, blow head gaskets, etc. He said that those engines are designed for higher boost pressures (around 60 psi,) for TWO turbos, and most importantly they are 18:1 compression ratio engines, so the only way to make one of those conversion kits work is to change all the cylinder kits to lower compression ratio and do a whole bunch of other changes to make the single turbo compatible, including ECM reprogramming.
Good piece of information there.

The cause of the problem in our friend's C-15 that my son drives was one of the exhaust manifold steel inserts that they use in these Acert engines in conjunction with the gaskets to compensate for the higher exhaust temp...they are known to come out of the ports and pass through the turbos. Exactly what happened here....and that was that tinny noise he heard was it being blown out the stack. Two were completely missing, and a half of one we found inside the hot side of the top turbo. It cleaned the fins off the top turbo inner impeller. What a miserable design those things are, those inserts.

So today it's getting 2 new turbochargers. A cheap date in one aspect, not so much in others. But coulda been a LOT worse.

Sorry for the off-topic story, but the point was about injection timing and I got veered off course a little.

When's the last time you had the head off that engine rank? I'm reaching for stuff now, but trying to think of everything top to bottom. The black particles in the radiator...sounds like deteriorating inner coolant hose material, or maybe O rings breaking down somewhere...