I finally got around to cleaning up the oil cooler a little bit to figure out where the leak is on the D7 3t. After degreasing I still have this small section dropping some oil at the bottom. Just looking for input on if it's worth pulling and soldering to fix or if a bypass would be better. I do have a good soldering iron and could probably get it sealed but is it more hassle pulling it than bypassing is my question.

Hi, BVAL.
I'm 'justa pore, dumm bulldozer op'rator' and so don't know much and somebody will likely come along to tell me I'm 'fullavit' later but, personally, I'd be pulling it and soldering it up. I 'figger' Cat put it there for a reason and they had done way more homework on the subject even back then I have done so maybe they hadda clue-er-two.

Just my 0.02.

what we did for the d4 was get a after market trans cooler for a toyota landcruiser and mounted that in front of the rad and blanked the oil cooler off completely with devcon epoxy. any heavyduty trans cooler would work.

if its only a small leak yes pull it apart and solder it up. you can clean the core properly while you have it apart.

That is what I figured would be recommended. I'll figure out how to pull and drain it, looks straight forward. Then clean and solder and put her back together. Glad it did turn out to be a minor leak and only looked so bad from leaking for so long and the fan flinging the leaked oil around.

After doing more research it seems that since this leak is in the fins simple soldering job might not be the case. Most stuff I could find said it would probably need to redo the core or the leak will just transfer. Not sure that's accurate but it did also say that leaks in the fins generally occur from rust from someone not running antifreeze and only using water. The previous owner did only run water in it so that seems like a legitimate concern for me. I'll probably still try it but will also be checking some radiator shops for repair pricing in case it is beyond me.

I found someone that sold me a couple oil coolers for cheaper than the cost of repair. One was good and tested other leaking. The leaking one (much nicer condition) is actually good just the cap that the person used to test it didn't screw on enough to not leak air, it maintained 125 psi no issue when properly capped. I'll fix the old one and have a couple spares just in case.

My issue now is that I cannot get my damaged oil cooler out of the machine. I have removed all the bolts and unhooked the lines per the servicemens reference book. I can move the cooler around but can't get it to come out of the opening. The service book shows them just tilting the bottom out but I don't have the room without it hitting the radiator and obviously don't want to damage that. Seems nothing is going to be simple with this machine.

Tried getting this thing out again and I'm not seeing how it can come out without cutting the grill mounts off. Do any of you have any suggestions.

V14, I have never worked on the D7 machines, I have done some on the D8K, could you lower the belly plate under the nose of the rad Assembly? Be very aware these belly plates can very very very fatal, most I have dealt with have been over 160kg in weight each, some have been welded on to replace worn threads on bolts or studs,
Im not sure if this is possible for you or this machine, if you have good welding skills to hold the grill again that is an option with the brackets.

Both the top hood side and the belly have been welded by someone. I can weld but do not have a welder or breaker space in my panel to install one so it wouldn't be ideal to cut those mounts off. Seems I may have no other option though.

No way to move the cooler to one side then swing the other side out?