Little rear end help please

[rblong]

I tracked my car (road course) this weekend for the first time. After the last session I noticed when I came back and was reloading on the trailer that there was some oil dripping from the rear of the car. There was some water on the course so it looked like a lot of water/oil. I thought well damn - I must have blew something. I got home and unloaded it and put up on the lift. The only oil was on the pessenger side of the rear end - from the axle back. I thought oh well I blew a seal out of the drivers side. I just pulled and the brake and associated components are dry so it is not the seal. I also noticed the vent tube for the rearend is on that side. I have been running this rear for 7000 miles and have never lost a drop of gear grease, but then I am street driving and not hitting corners at 60+ either. It is a 9 inch ford with Currie guts/axles. The vent port is a nipple about 1 inch long. The whole area of the axle/shock etc from the center section to the driver wheel is wet, but past the wheel inside the hub it is dry - so it is not the seal. The rearend grease is low. You ever heard of this? Any help here.

Thanks in advance
Bruce

[Tom Wells]

Bruce,

Welcome to the slippery slope - pun intended.

Exercising the car on a real race track will cause a series of these kinds of problems. I have melted off the plastic dipstick in my power steering, lost engine oil through a variety of places such as external plumbing for filter, cooler, valve covers etc., had shocks lose their oil and many more.

The cause for this leakage is stressing the car's components in ways that are never encountered on the street. Heat builds up and away goes one or more kinds of fluid.

Most kit cars are not constructed with good resistance this kind of usage, so these leaks are going to happen. Even those that are targeted to the track have usually some period where things go awry and need mods to make them work correctly under track duress.

So if you are going to do this kind of activity again, you need to put on your Sherlock Holmes hat and figure out where this leak is, and then come up with a way to correct it.

If it is the differential, try to find out - maybe from Currie? - how to add a leak-resistant vent. It might only take a little baffle to accomplish this.

Be prepared to have other episodes - it's part of the experience

BTW, keep an eye on your oil pressure in turns, especially if you get a set of track tires which allow cornering at higher Gs....

Tom

[rblong]

Thanks Tom,

I will call Currie tomorrow. I cannot see any other place it can come from other than vent. I have noticed on some other cars a small tube with a cap of some sort at the end. I always thought it was to keep moisture out - not fluid in, but I have probably just been proven the law of assuming again.

I been watching oil pressure. I have a canton deep sump with baffles and have not see any fall off of pressure, of course at the same time going into a high G turn as a noobie road course driver tends to make you watch the road more than the gauges

I will post what I find -

Thanks again
Bruce

[tcrist]

Bruce,
I believe the oil is coming from the vent. You will more than likely need to put a hose on the vent tube and run it up high on the frame. Most 4X4's use this to keep moisture out but you would need this to keep the hot oil from splashing out. IMHO

Terry

[rblong]

Thanks Terry, I am thinking the same thing.

Bruce

[rblong]

Just talked to Currie, and in a road race application they recommend running a hose to a "chamber" like a fuel filter and then extend the hose to as high as posssible in the chassis. The oil is supposed to collect in the chamber and allowed air to burp off but allow oil to return to rearend.

I will give it a try this evening and once I hit the track again I will let everyone know.

Thanks for the help.
Bruce

[Rick Parker]

I found this hose as part of the emmisions sytem on a Nissan at a wrecking yard, almost a perfect fit for the purpose. Works perfect.

[IMG][/IMG]

[pmfranke]

I used a chainsaw gas filter and a piece of tubing just like Rick Parkers set up.It works great and very light weight .The rear end is the only place my car doesn't leak from. Ha ha.

[rblong]

Thanks again guys. My only real problem with all this is it will likely be a couple weeks before I have time to hit the track to test it.

Road racing is addictive!

[rblong]

Well, I ran the straight vent hose to above the wheel height and up until this weekend it did not leak out the vent, but I ran the corners harder than I ever did before (now I am running slicks). Not a lot, but enough we noticed a little on the inside of the wheel. I am going to call Currie again tomorrow, but I am thinking I may need to put larger chamber that would actually collect it and then run back into rear?

I guess what Tom said was correct -

"Be prepared to have other episodes - it's part of the experience "

Thanks for any help,
Bruce

[Jac Mac]

Shift the breather fitting on the axle tube in closer to the center of the car if its not already there. Also fit baffle plates with tubes for the axles to pass thru in the housing on both sides of the third member in such a manner that the baffle plate is closer to each wheel than the end of the piece of tube. With these in place the lube will be retained in the area around the third member for longer. What is happening at the moment is that all the lube is ending up in the axle tube during long fast corners ( particularly on slicks ). If you were to compete in a longer event the third member will experience early failure due to lack of lubrication.

Jac Mac

[fsstnotch]

This is a VERY common issue with the 9". In the past I have used a very nice looking catch can from art morrison. Alot of times even with a short piece of hose the oil will soak the filter and prevent it from doing it's job well. I'm sure you could use any catch can, but I liked the art morrision model and it worked great! It costs $45. i dunno if this link will work but if not, check out the art morrison catalog on www.artmorrison.com it is on page 7 part # 40403030

http://www.artmorrison.com/2006cat/2...wnload+Catalog

[CHANMADD]

It looks to me that if you leave that hose where it is ,when you jack the car down its going to rub on the radius rod.I would put a large inline filter,like a fuel or diesel filter and then route a hose to the middle of the car with the filter you have at the end of that.

[vettestr]

As Tom wells mentioned the oil pressure concern already I would suggest an ounce of prevention. You may not see quick dip/loss of oil pressure or be too busy to even catch it. A pressure switch wired to a red light monitoring your oil pressure is cheap insurance.
If the light flickers or comes on then there are a couple of ways to go after the issue. (accusump - new pan - or both) but light coming on is better than a sun bearing telling you of the problem. a link to Jegs and switch http://www.jegs.com/webapp/wcs/store...45853_-1_10337

[fsstnotch]

Originally Posted by vettestr

As Tom wells mentioned the oil pressure concern already I would suggest an ounce of prevention. You may not see quick dip/loss of oil pressure or be too busy to even catch it. A pressure switch wired to a red light monitoring your oil pressure is cheap insurance.
If the light flickers or comes on then there are a couple of ways to go after the issue. (accusump - new pan - or both) but light coming on is better than a sun bearing telling you of the problem. a link to Jegs and switch http://www.jegs.com/webapp/wcs/store...45853_-1_10337

Did we read the same thread?

Monitoring your oil pressure is a great idea... but I'm not so sure it's necessary to fix a pressurized 9"....

*EDIT*
Went back and reread the thread. I see where your coming from. My bad! Warning lights are definitely useful if you are going to push a car to it's limits.

rblong, put a catch can on your rear end and it will solve your leaky gear oil problem.

[Rick Parker]

You can also look in or consult a Cirlcle Track source for seals that fit in the axle tubes (not the ends) and prevent the oil from being forced into the tube by centrifical forces. Used by circle track folks to prevent early gear failure as previously mentioned.

[CHANMADD]

Huh!!!I thought you were talking rear ends?

[fsstnotch]

Originally Posted by CHANMADD

Huh!!!I thought you were talking rear ends?

you must have read the post right when I did.

We are talking rear ends, to fix rblong's problem

When pushed to hard, the 9" will pressurize itself to the point of pushing the gear oil out of the weakest point. If you are running a 9" without a vent.. I would HIGHLY suggest using one. If you use a vent, then that will be the weakest point and where all the oil will be pushed. If you don't... it'll go out somewhere else which will be alot more costly! A simple catch can with a breather will prevent spillage and over pressurization.

[rblong]

Thanks all, sounds like the catch can is the ticket - I will do that next.

BTW, that is not a picture of my set up and I already have a road race oil pan on the FE.

Thanks again,
Bruce