Oil & Fuel Hyd Oil Cooler Leak

[gumshu]

Some of the guys on the Bobcat forum posted entries re: leaks in faulty Hydraulic Oil Coolers. These leaks are in the Bobcat CT HST series which are essentially same as the Kioti CK HST series. Have any of you CK guys experienced this problem?

[VictorW]

Various Kioti members have had to replace theirs. My CK30hst, similar to the CT230, originally came with steel lines to the cooler and the cooler leaked under warranty. The fix was a new cooler and the steel lines were replaced with rubber hose lines. It seemed to last a little longer but then out of warranty, the second cooler started to leak. I bought another cooler and read posts where members were rubber mounting them with good results. I took the new cooler and drilled out the mounting holes so I could place rubber gromments in the two holes. I then cut two sections of 1/4" steel tubing that would fit inside the grommets and over the mounting studs. When remounting, the nuts tighten against the steel tubing and don't compress the grommets. You can grab my cooler and actually move it a little. It's been over 200 hours without a problem compared to the 100 hours or so the other coolers lasted with the hard mounting.

I had looked at a CT230 a year ago and that particular cooler looked different than mine. My cooler has passages like a car radiator that are thin and wide. The CT230 cooler had round tubes which I thought the wall of the tubes might be thicker and handle the vibration better. Either way, I'd still rubber mount the cooler.

[Coyote machine]

I would suggest you do a search on this forum to find relevant threads about this issue with the CK series. I remember there being pics and discussion about how to better mount the cooler so it would not suffer from excess vibration and result in broken tubing/lines.
I think you'll find what you need to apply to the Bobcat situation if you search what has been done on the CK's.
Can you post some pics of the Bobcat setup? Maybe the Kioti group can help figure out a solution to your design issue(s).

[gumshu]

Thanks guys. I think I'll try VictorW's solution as a failsafe. It seems to be a common problem, so I'll try to avert the problem. My cooler looks like the one below listed on ebay. It has rubber hoses on the bottom side.

http://www.ebay.com/itm/Bobcat-CT225...79756636968069

[VictorW]

The picture on the ebay site is what my cooler looks like. The seller mentioned that Kioti has gone with a new manufacturer. I wonder what the new coolers look like and if they are made a little tougher. Maybe that's what I saw on a Bobcat with the cooler having round tubes. Either way, that ebay price is at least 50% less than I remember paying several years ago.

I wouldn't call it my solution because other members started rubber mounting their coolers in some fashion before I did mine. Drilling the holes bigger to accept the rubber grommets and using the 1/4" tube in the grommets for the nuts to tighten against was what I thought would work best. I've seen this type of mounting on cars and other vehicles when vibration needs isolated.

[LaVoie Equipment]

That ebay listing is the "Original" Cooler - AKA Cast Cooler.

New cooler is a tube and fin type. Round tube and fins like your radiator. NOTE: If you purchase a replacement you need INLET and OUTLET hoses also.

Typically Cast cooler will split in situations where consumer/operator does not allow Hydraulic Oil to warm properly (cold environment). Cold oil will cause HIGH pressure and cause split.

[VictorW]

That ebay listing is the "Original" Cooler - AKA Cast Cooler.

New cooler is a tube and fin type. Round tube and fins like your radiator. NOTE: If you purchase a replacement you need INLET and OUTLET hoses also.

Typically Cast cooler will split in situations where consumer/operator does not allow Hydraulic Oil to warm properly (cold environment). Cold oil will cause HIGH pressure and cause split.

Thank you for advising the difference of the new cooler vs the older style. From what you've seen, do you think the new cooler is better and will hold up better? I see that the new cooler costs more than the older style did and would require the two new hoses but if it wouldn't crack and leak, then it would be worth the money to have a possible permanent repair.