Welding a Dry sump Tank

[Brad93]

There shouldn't be any oil on the new boss or the outside of the tank

Aluminium is porous and has been in the engine bay of this car for god knows how long, it will have oil in the pores on the inside and outside.

 

[Brad93]

Have you ever welded a used sump or catch tank before?

 

[dab4318]

Have you ever welded a used sump or catch tank before?

Yes I have, Got asked to weld a leaking sump up. Went to the blokes place to do it. He had forgot to mention it was still attached to the engine, full of oil and still in the car! At least he had a ramp I suppose.

 

[normspanners]

it will have oil in the pores on the inside and outside.

Yes ,many and the way I said to do it is the way I do it, weld it before drilling if poss, then it is easy to test, dry sump tanks are usually in the boot, or separate compartment, in the dry away from engine heat.

 

[normspanners]

Ah no it isn't.

Massive difference in air flow the air in a dry sump system is pumped with some oil as danny says

when each scavange pump cm move more oil than the pressure pump, they throw a hell of a lot of air up to the tank, infact dont even think of them as scavanging oil more like fog. there is that much air goin through that tank when its revving hard, that not all the fog sereates out and there is a lot of oil carry over to the catch can to the point on some setups you need that oil back otherwise you'd be losing oil way to fast

 

[PhillipM]

That also depends on your breather system, the engine is sealed on mine but the tank itself has pretty large breathers up to the catch tank, it doesn't seem to throw up too much vapour.

 

[normspanners]

On the honda and others bda's I used a semi vacuum system to restrict windage ie restricted input to cam cover otherwise the seals can pull dirt in. I then used a short -12 from the scavenge pump to bulkhead then -16 through the car to the tank to aid the oil separate on its travel back to tank also helps lower pumping losses. Also there will be cavitation if not aeration, either seems to froth the oil. Returning the oil from the catch tank to below tank level worked very well for us coz no need to remember to check catch tank. I also ran ball valve on tank outlet for long term parking to stop empting the drysump tank into the engine when that was used the ign key or battery masterswitch key was attached to the valve handle !
As long as the breather filter is below the bottom of the drysump tank, Then when it rolled which it did several times it didnt make any oily mess or lose any oil,it was thrown back over and off again.

 

[PhillipM]

I haven't bothered with the valve, don't have room for one, but the car is setup so it spins the engine over on the starter if the cutoff has been active since it last run, cranks for 6-7 seconds before firing the injectors and coils.

 

[dab4318]

I haven't bothered with the valve, don't have room for one, but the car is setup so it spins the engine over on the starter if the cutoff has been active since it last run, cranks for 6-7 seconds before firing the injectors and coils.

You boys are all getting to complicated and posh! I'm still on a dizzy and Webers!

 

[PhillipM]

Ah, distributors, guaranteed to be absolutely perfect at one spot, and wrong everywhere else

 

[dab4318]

Ah, distributors, guaranteed to be absolutely perfect at one spot, and wrong everywhere else

A lot simpler though

 

[normspanners]

Yeah the good old days when you could fix things with a screwdriver and hammer did a rally the other day with a lotus twink and it brought back memories the guy didnt know how to drive it, he was driving it like a modern car and fueled it up so there I was in pissin rain holding the leads off the plugs getting shocked all over, while trying to find the sweet spot to help clear the plugs. didnt have my trusty snap on plastic plug lead pliers hehe dont need them nowadays .