trans vent overflowing

wowzer52 · Post by **wowzer52** » Sun Feb 20, 2011 11:00 pm

On my buddies F-32 GM Crusaders 270hp velvet drives, when the trans fluid is full to the mark, while under way, trans fluid comes out the vent, after approx ten hours of running the trans fluid is a quart low, refill to the mark on the stick and after another ten hours, another quart low. Does someone know what or why this is happening?

gumper · Post by **gumper** » Sun Feb 20, 2011 11:25 pm

One thought is that he is over filling the trans. THe fluid level should be checked at operating temp not when it is cold. dextron expands alot when heated. Once the hot level is established you cat mark the dip stick with a cold level. This is the simplest possible reason I can think of.

Big D · Post by **Big D** » Mon Feb 21, 2011 12:27 am

I agree with Gumper. Most common mistake. The only other thing I can think of is water in the oil or perhaps running too hot due to insufficient cooling. Temp gun would really help here.

prowlersfish · Post by **prowlersfish** » Mon Feb 21, 2011 6:23 am

over filling is the first thing to look at . What is he using for fld ? some use motor oil in the velvet drives and it will foam if run at 3000 or above.

wowzer52 · Post by **wowzer52** » Mon Feb 21, 2011 10:44 am

Thanks for the comeback, he said he uses dexron II and we'll check for temperature and water in the fluid or milky oil. I haven't looked at it yet but I will today. I guess there could possible be a leak inside the trans oil cooler and will check for that.

Big D · Post by **Big D** » Mon Feb 21, 2011 12:18 pm

Hope you guys find the issue, that would worry the sh%$ out of me...$$$. Keep us posted.

wowzer52 · Post by **wowzer52** » Thu Apr 21, 2011 10:48 pm

I finally got a chance to look at my buddy's trans and while the engine is running all the trans fluid is pushed out the trans vent within an hour. I watched it happen. Do you think it may be caused by a plugged trans cooler creating back pressure? It did not do this until he had the engine rebuilt by a marine service. They removed the trans to rebuild the engine and replaced the trans when they put the motor back in. By the way, that marine service is now out of business. Could they have hooked hoses up wrong or backwards? I'm stumped.

prowlersfish · Post by **prowlersfish** » Thu Apr 21, 2011 11:29 pm

The vent should hold slight pressure . ( its not open ) it has a check valve in it so it could be bad or been damaged .

Over filling is still the first thing to check

wowzer52 · Post by **wowzer52** » Thu Apr 21, 2011 11:32 pm

I checked the level for over filling but even when it's a pint low it still pushes it out.

prowlersfish · Post by **prowlersfish** » Thu Apr 21, 2011 11:50 pm

I would look at the vent If the check valve in its bad it cause the issue , I did not know it had a valve untill I got a new one a few weeks ago .( broke the old one pulling the trans out. they could have damaged it when the worked on it.

wowzer52 · Post by **wowzer52** » Fri Jul 15, 2011 11:46 am

I found it! The hoses to the cooler were hooked up backwards. Changed them to match the other engine and everything is fine. The marine service that did the work on it obviously needs some schooling.

Big D · Post by **Big D** » Fri Jul 15, 2011 12:05 pm

OK, so I'm trying to figure out how that would change anything! As long as the oil lines are hooked up to the oil ports on the cooler why would it matter the position? They aren't directional...are they? Does anyone have any insight on this?

Torcan · Post by **Torcan** » Fri Jul 15, 2011 7:46 pm

wowzer52 wrote:I found it! The hoses to the cooler were hooked up backwards. Changed them to match the other engine and everything is fine. The marine service that did the work on it obviously needs some schooling.

I guess that explains why they went out of business.

larryeddington · Post by **larryeddington** » Fri Jul 15, 2011 8:59 pm

Having just had my oil coolers off and cleaning them, I cannot see flow direction of the oil making any difference. If you look in at the end of the cooler it looks like the header on a boiler only smaller. That is a number of pipes that to straight through. Some thing could have stopped up the oil line and when reversed it cleared?

prowlersfish · Post by **prowlersfish** » Fri Jul 15, 2011 10:02 pm

Big D wrote:OK, so I'm trying to figure out how that would change anything! As long as the oil lines are hooked up to the oil ports on the cooler why would it matter the position? They aren't directional...are they? Does anyone have any insight on this?

On most coolers it should not mater .