Thinking about installing an BMW M6 engine in my Z

[Patcon]

I also wondered how the dissimilar metals would behave long term.

[grannyknot]

Blue,

Was that plumbers solder you were using?

I ask because this stuff that I was going to use is quite different. AC systems really test solder joints and this stuff has a working temp range of 350*F to 500*F and a tensile strength of 20,000 psi.

My oil temp rarely gets over 200*F and 80psi on a cold start.

 

But you have started me thinking of other ways of doing it, I can't use steel pipe as the oil pump is cast aluminum, aluminum pipe is a bugger to work with. I could do some AN fittings and braided SS hose

or friction fit cooper tubing.

I'm open to suggestions.

 

 

[rossiz]

i agree w/blue's concerns - the combination of vibration and the long arm with the weighted pickup screen will really stress the solder joint and it's a bad place for a failure...

 

why not weld a female threaded fitting onto each end of the part you cut and use compression fittings with a bent steel tube? then you can adjust it to right where you want it. 

[grannyknot]

 

 

 

 

 

why not weld a female threaded fitting onto each end of the part you cut and use compression fittings with a bent steel tube? then you can adjust it to right where you want it. 

That's probably what I will end up doing but I'm not going to throw away the copper tubing idea just yet,

Still need to do some testing, to it's credit the copper tubing is held captive in position and the end of the p/u tube is supported, also, the entire modified area is submerged in oil at all times.

 

I picked up my new 1972 240z today, the car that will be the home for this bmw transplant.

 

 

I can't in all good conscience keep modifying my early 1970 matching numbers Z, I'll put it back to stock and pass it on to someone who cares about original stuff. The new 72 Z can then be heavily modified without too many people screaming at me.

 

Also, I got my oil pan back from Ben the aluminum welder, he did beautiful work.

The first thing I did though was start cutting it up for the final fit testing.

[rossiz]

nice work indeed - i would be hard pressed to resist grinding it all smooth and polishing the whole thing up! 

[Patcon]

The welding looks good, but I am with Rossiz about wanting to dress the welds down. It would really look clean that way

[grannyknot]

Well, now I am ready to give up on the idea of soldering, a waste of $40 and many hours of time but

there it is. The dis-similar metal solder worked well enough on the copper but I could not get it to take hold of the cast aluminum. Both metals were pristine clean and fresh metal exposed but could not get it to flow onto the aluminum, maybe it was because it was cast.

So...I've ordered a couple of aluminum -10 AN fittings and some SS braided line. I cut off the threaded part,

weld the stubs onto the cast aluminum oil pump halfs and join them with the braided line.

That's the plan at the moment.

[John Coffey]

Don't grind the welds and don't use copper or solder for the pickup tube.  Bend one out of thin wall steel tube.  Test the pan for porosity using boiling water.

[Patcon]

John

Why don't you grind the welds? Is it an issue with weld porosity?

 

Also are you related to a Bill Coffey at Zcon with a blue race car?

[grannyknot]

John, I wasn't going to touch those welds. The boiling water trick is a good one, it should expand any pin holes so I can mark them with a pencil.

 

Thin walled steel tubing; How the heck would you attach it to cast aluminum? Friction fit, sealant?

Won't dis-similar metals cause electrolysis between the touching surfaces as the oil passes through?

[John Coffey]

Why are you attaching to cast aluminum?  Maybe I've missed something on the oil pickup with the M6 engine.

 

OK, I looked back at one of your pics.  Aluminum tubing would be better... :-)

 

Regarding grinding the welds - I'm a function over form kinda guy.  A good weld is beauty in and of itself.  And who's going to be looking at the oil pan anyway?  Spend the time and money somewhere else on the engine.  Also, you can grind too much and cause problems.

[grannyknot]

Finally got the pan back from the Powder Coaters, he wasn't coating it though. I had him take the pan up to 650*F for a couple of hrs and then turn off the oven and let it cool slowly over a 14 hr period.

Now I don't for sure that it helped ease any stress in the aluminum but when I unbolted the pan from the steel plate there was only about 1 mm difference from one end to the other, I'm pretty happy about that!

I did the test with methyl hydrate and also with hot water, no leaks of any kind

I'm tempted to cover the steel plate I was using with emery cloth and work the pan back and forth until it is truly flat again.

The first two pics are with no bolts holding the pan down.

 

I'm also wondering if I should fill the inside seams with a flexible sealer of some kind.

Chris