Cat C13 with coolant getting into the oil

If you have a Cat C13 (maybe C10/C11/C12 also) that is getting coolant into the oil, I have found a manufacturing defect in a C13 that caused coolant to run down past the cylinder liners even before pressurizing the cooling system. I will post more info, if anybody else has this problem.

 

The bores in the block, for the liners, are bored crooked (Front to back). The liners when installed but not clamped down, are .005" higher in the front than the rear of the liner. The rear of the liner is seated on the counterbore ledge, but the front is held up .005" off of the seat. When the liner is clamped down, the bottom of the liner is moved back against the lower bore in the block, and then distorts to the point, that the liners o-rings leak coolant down the outside of the liner in the rear of each liner. The liner o-rings are .035" larger OD than the bores in the block. They do not leak until the liners are clamped down. I never saw anything like it. We are going to be able to repair the block, with upper repair rings. I am told that Cat originally used thicker o-rings , until they got too many complaints about how hard the liners were to install. They now have thinner o-rings, and the o-rings are more critical to the liner bore being concentric to the block deck.

 

Yes, the liners were at .007" protrusion when clamped down. That is the high side of the spec, which is what I ALWAYS aim for!

 

If the had a small flange, it probably would crack, but these are deep counterbores, so they spread the distortion over a larger area.

 

I measured the counterbore depth all around. They were perfect after I had machined them for .010" shims. As I stated in my previous post, they leaked only when they were clamped down.

 

I do not know the mileage, but it is high. The reason that they tore it down, was compression in the cooling system, which is normal, due to Cat sending them out with the liners at the low side of the spec. I am convinced that all of the truck engine manufacturers could reduce their head gasket problems by 90%, if they would run the liner height at the high side of the spec, instead of the low side. All that they care about, is that it lasts until the warranty has expired. Then they are glad to sell the trucker parts to repair their poorly manufactured engine. They make more money, selling parts, than they do, selling the engine originally.