Cleaning the D4D Cooling System

Boy it,s been so long since I worked on one but seems there is a plug in the bottom of the oil cooler or around it to drain it & possibly the block. Also it seems there should be a plug with a hex head someplace there in the side of the block.Cat used to have a radiator addative part No. 8T1589 that was good but you,d have to check with a dealer to see if they stock it or another number one now.

Hi SJ

CAT does still carry this but the amount required was defined as 1 quart per gallon of coolant. Other products like the Purple Ice only use 4 ouncs per gallon.

Are the CAT guys right about the amount of coolant additive.

I think them guys are all wet using that much conditioner. The one you suggested should work fine so go with that. The Cat container should have the amount to use to treat a cooling system I,m sure so if you decide to go with it look on the can first before you buy it & go from there.

Hi SJ
The counter folks were reading from the back of the container. I will call to Peoria tomorrow and see what they can tell me about their product. I think the amount is way too much, but we will see and I'll let you know.

The counter men went to the shelf and read the back of the container versus some tech literature they have available. The actual amount when first charging new coolant is 1 quart per 8 gallons of coolant. I still have not found the engine block drain plug yet. Sounds like time for a more descriptive post.

It been too many years since I retired but worked on lots of those engines so it comes to mind there should be a plug on the bottom of the oil cooler to drain the complete system but I,m pretty sure there is one up a ways from the bottom of the block going into the block. I just looked at a picture of the 6 cyl. engine same as the 4 & it points out the drain at the cooler about half way back on the left side of the block where the cooler is. As I mentioned before, can,t remember if there is a separate plug in the block on that side or just the coooler drain which should drain the block. Let us know how you make out draining it.Just to remind you the plug would be part way up the block in line where the bottom of the liner is in the block but would be just above the "O" ring seals on the liner so don,t think the plug should be at the bottom of the block.

Hi SJ,

I am looking at the parts book. In the diagram for the cylinder block (right hand side view) there is a plug with part number 8M9307. It shows its positioned just above the liner seal on the #4 liner. It shows on the diagram as dashed lines which seems to suggest that it's actually located on the left side of the block in the vicinity of where the torque oil heat exchanger is located. I have also found the torque convertor oil cooler and found a plug in the bonnet group as well a plug in the bottom of the oil cooler.

I'll let you know if I hit water anywhere.😄

Hi SJ,

I am looking at the parts book. In the diagram for the cylinder block (right hand side view) there is a plug with part number 8M9307. It shows its positioned just above the liner seal on the #4 liner. It shows on the diagram as dashed lines which seems to suggest that it's actually located on the left side of the block in the vicinity of where the torque oil heat exchanger is located. I have also found the torque convertor oil cooler and found a plug in the bonnet group as well a plug in the bottom of the oil cooler.

I'll let you know if I hit water anywhere.😄

SJ
You were right on the mark and the parts book seconded your motion. It was hiding just forward of the oil cooler in the block and is easily accessible with a 3/4 inch socket and a long extension. It loosened with a good pull and I found the water I was looking for. Thanks for taking another look and not giving up on me. It sure was easier to find with some helpful directions. Thanks again. Tomorrow I will see how much crud drains out.