Discussion:
Komatsu FG30 Spitting Trans Fluid out Breather

Have a Komatsu FG30 with torqflow trans. Older style with iron case and aluminum valve body. Nissan 2.5L engine. I believe it's a ST-16. I can get more info later.

Truck came in with no reverse. Found snap ring blown out of clutch pack and was sent in to be rebuilt. Put trans in with new pump, torque convertor, etc.

Now trans fluid spits out of the breather after a few minutes of run time. Fluid level is in the middle of the marks and it is filled with Crown trans fluid. (I believe its Dex III...smells and looks like it at least).

I've heard they had issues with wrong fluids in the past. I also replaced the cooler lines.

Any suggestions? The truck travels fine. The fluid doesn't appear to be aerating. If I pull the dip stick up and release the pressure, the fluid stops flowing out of the breather.

This trucks been here two months while waiting for the trans to be "refurbished". Then found additional problems after repair with brakes, yadda yadda yadda.....customer is mucho **** off o so time is an issue.

Thanks!
  • Posted 12 Apr 2012 09:23
  • By Thrasher
  • joined 8 Oct'11 - 4 messages
  • Wisconsin, United States
Showing items 1 - 7 of 7 results.
That must of been fun.
  • Posted 18 Apr 2012 10:39
  • By mrfixit
  • joined 11 Dec'08 - 1,434 messages
  • New York, United States
I thought I mention in original post that rebuild company claimed they didnt touch the valve body even after I found inching valve assembled wrong.
  • Posted 18 Apr 2012 07:16
  • By Thrasher
  • joined 8 Oct'11 - 4 messages
  • Wisconsin, United States
Took the valve body apart and there are 2 paper gasket and one metal spacer. Found the company was definitely in there during the rebuild. The two paper gasket are identical except in one spot.... Near the breather. They were flipped and it was allowing a small amount of oil to blow by into the breather port. They also used a die grinder to clean off the old gasket leaving deep swirls in the sealing surfaces and spacer.

Fixed and gone. Always take a look for yourself and don't take someone else's word for it.
  • Posted 18 Apr 2012 07:14
  • By Thrasher
  • joined 8 Oct'11 - 4 messages
  • Wisconsin, United States
Just as a matter of course, we always have the radiator boiled out and checked after a major job such as a radiator and/or engine.
  • Posted 13 Apr 2012 18:10
  • By 7777
  • joined 8 Mar'11 - 649 messages
  • New York, United States
thanks for the assistance. JCFORKLIFT@gmail.COM
Thoughtof that. I replaced the lines beforehand but did not flush cooler like I should have. Don't have equipment other than garden hose and air pressure etc.

Thanks for replies. Dont like shotgunning parts like what we've been doing.

Anyone see a pump or pump seal fail and do this? or bad regulator valve o rings? The breather sits in regulator valve chamber.
  • Posted 13 Apr 2012 04:13
  • By Thrasher
  • joined 8 Oct'11 - 4 messages
  • Wisconsin, United States
I agree with 7777 I have seen that a couple of times and it was a restriction in the cooler lines, try blowing them out and the radiator cooler, Just be careful with how much air pressure you use in case there is a sgnificant restriction.
  • Posted 13 Apr 2012 02:26
  • By bigGlittlestar
  • joined 12 Aug'08 - 139 messages
  • United States
A shot in the dark, maybe the radiator is no good and pressure is biulding internal to the cooling tubes. Any mixing of fluids in either the radiator or trany?
  • Posted 12 Apr 2012 20:39
  • By 7777
  • joined 8 Mar'11 - 649 messages
  • New York, United States
thanks for the assistance. JCFORKLIFT@gmail.COM

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