Gearbox Cooler

[BOYRCR]

I have tried the search option and dont get much.

Has anyone fitted a gearbox cooler to there car and if so what kit did you use or did you make your own?

[Regie]

for manual box??

didnt think you could cool them....they dont have a pump to pump the oil around

auto on the other hand...coolers are easy on them

[BOYRCR]

That's half my problem. I have found a couple of coolers that will work. I have contacted my gearbox guy and he will pull apart my gearbox ok so I can get a oil pick up welded into the lower half of the gearbox on the side and use the oil filler hole as a return then put it back together for $300 or less. I have also found an oil filter head with temp gauge outlet. I will use dash fitting and braided hoses. All I need is a pump. I have found one that will work but doesn't have threaded inlet and outlet and it is $360. I have found a couple of cheaper options but they are much bulkier.

[NitroDann]

5 speed or 6 speed? How much torque are you laying down?

Dann

[BOYRCR]

5 Speed.

I have a Quaife gear set in the gearbox. It is getting hot because the car is turboed and the external waste gate pipe opens up just before the bell housing. I will be wrapping the exhaust and redirecting the screamer pipe to help reduce it aswell. The gearbox is getting so hot I have a mark on the palm of my hand from a couple of laps at power cruise on the weekend. The sole purpose for this car is track days and competition now. So when it will be dríven it gets dríven hard.

[NitroDann]

My post was almost a trick question. I was testing you to see if you had actually done the research or just wanted a hektik cooler.

Awesome. you passed

Let the technical discussion begin!

If my memory serves me correctly, GB oil starts losing its shear film strength and allows wear around 130*C. Have you tested the temperature of the oil? Its possible for the oil to not be 130c, but the knob is hot enough to burn you (maybe 55c).
Welding in fittings is easy enough, but its hard to know where the oil is, Id NOT weld fittings in the bottom but rather low on the side.
And Id weld a couple.

Have you considered using a secind hand oil pump from... well any engine, and running it off a machined V pulley with a longer alternator belt, using a backplate to complete the oil pump housing? You will need a baffled reservoir and breather system very similar to a dry sump in order for this system to work effectively, and reliably.

Discuss

Dann

[BOYRCR]

My gearbox guy told me that they normally use the filler and drain plug for this application. Due to the drain plug being on the bottom that is not possible. So a pick up hole will need to be drilled and a adaptor welded on. This would have to be installed on the lowest part of the box possible. I was going to ask him where is the best spot when he pulled it apart. I was then going to use an electric pump so I dont waste horse power and it can be controlled in car. I was then going to use a remote oil filter head with a temp guage adaptor in it to monitor the temperature. Then run the oil through the cooler back to the filler hole/return.

I'm not sure what you mean by a baffled reservoir or how it will fit into the grand scheme of things (I know enough when to say I don't know what you mean)

Will a breather be needed? The gear box dosn't have one from factory.

[NitroDann]

Just going by memory here.... no breather... be right back going to look at the 5 speed in my shed. back in 2 minutes.

Dann

[NitroDann]

Uploading some photos I just took to help the discussion. be 5 mins.

dann

[NitroDann]

here we go.







This is the stock breather.

Im talking about a system basically the same as a dry sump, with a reservoir, which in this case is mostly about de-aerating the oil, rather than having capacity like its used for in a dry sump system.

As for electric pumps, of course they drain horsepower. Are you kidding here?

Dann

[BOYRCR]

With all the gearbox's I have pulled out and swapped I have never noticed the breather. I will have to have a closer look for mine when it comes out again and make sure it is in ok condition.

How air rated could the oil get? would it be any worse than when it is only in the gearbox. I would assume getting picked by the gears and run through the gearbox that this might air rate the oil a little but no more with the pump and cooler setup.

I will have to make sure the cooling lines are full of oil and the gearbox has the correct amount in it when filling it up so as not to starve the gearbox. This is one of my concerns. I'm also worried about the pick up running dry but with the right amount of oil in the box and lines I think this might not be an issue.

Obviously the alternator will work harder and drain HP but it is also a lot easier to conect an electric pump than a belt fed one and I'm running out of room to hide stuff in the engine bay. (high mount turbo and all the plumbing)

[NitroDann]

Although an engine oil pump WILL pull aerated oil through LARGE lines, you also need to get it de aerated so it will flow back into the box.

Im not sure how aerated the oil inside a gearbox is.. Honestly I wish I did..

can you mount a pump where the air con goes, should be plenty of room there?

Dann

[BOYRCR]

I had the air con installed when I had the last lot of work done. I am thinking of removing it. But it is really nice when you are waiting to go on the track. I know this sounds wrong but I have only just decided not to re-register the car.

[BOYRCR]

If a pump will pull aerated oil through then it should be able to push it through a filter and the cooler. Will a filter have any issues wit aerated oil?

[NitroDann]

Theres no way you will get aerated anything through a filter sorry.

Dann