Ed Scherer

As I was recently changing fluids on my car, I thought it was finally an opportunity to try out the Fumoto drain valves as a replacement for the block drains. I'll admit that the uncontrolled coolant shower experiences I've had in the past caused me to stretch the coolant changes, not wanting to repeat that experience more than necessary.

Searching through this forum, I found quite a few references to the Fumoto F109N (that it "should work," at least the threads are right, etc., e.g., see a few of the posts in the threads "Oil Pan Drain Valve Special and If it's not one thing it's another, need help!!!), but, curiously enough, I don't think I actually ever found a post where somebody said that they successfully installed them.

Researching a little further, I decided that the F109S might have a slight advantage over the F109N: a shorter nipple to which an SL-10 90° elbow can be attached, thus letting the 3/8" ID tubing be attached directly downward.

I wound up ordering two sets of this:

• "Fumoto Oil Drain Valve Kit for DIY Oil Changes with F109S (12mm-1.5)". That kit gets you an F109S drain valve (which comes with a F-103 fiber gasket), an SL-10 elbow-shaped plastic socket, an SH-10 straight plastic socket, an LC-10 lever clip, and 3 ft. of 3/8" ID vinyl tubing
• "ADP-109 extension adapter (12 mm-1.5)"

In retrospect, instead of that kit (the first item above) I could have just ordered an F109S and the SL-10 and saved a few bucks, as I don't expect to use the SH-10, and elected not to use the LC-10; the latter seems unnecessary given the protected location for the drains, and it's awfully close to the exhaust headers, so I'm not sure plastic would survive there.

Here are a couple of photos of what works. From left to right: F-103 fiber gasket (included with the ADP-109), ADP-109 extension adapter, F-103 fiber gasket (included with the F109S), F109S drain valve, SL-10 elbow-shaped plastic socket. 3/8" ID hose not shown.





Originally, I was thinking about leaving the plastic socket attached and capping it as shown below, but after seeing just how close that would leave those plastic parts to the exhaust manifold, I decided that they would likely not survive the heat and elected to just store them for future use (and not using the LC-10 lever clip at all) when it's time for the next coolant drain/refill.



Installation was straight-forward. I elected to use Permatex High Temperature Thread Sealant instead of the copper anti-seize I used on the drain plugs previously (anti-seize and which type, vs. thread sealant, etc., is a whole separate topic that has been discussed quite a bit in other threads).

I used the included fiber gaskets rather than aluminum crush washers. First, I attached the F109S to the ADP-109 and torqued to 20 Nm. Then screwed that assembly into the drain hole and torqued to only 20 Nm, even less than the 26 Nm recommended in See PSA: IMO, the torque spec for the block drains is wrong!. Easy enough to torque a little more later if it leaks (it hasn't), but hard to fix it if the threads are pulled out or worse. I got lucky in that after torquing, the levers wound up in pretty good positions.

20 mm crowfoot wrench on the torque wrench, set to 20 Nm:



Torquing the right side drain valve assembly (wrench on the ADP-109):



Right side drain valve installed. I had to bend the metal temperature sensor tube a little to keep it clear (from what I read elsewhere on this forum, I suppose I could have relocated that sensor to another cylinder). Drain lever is in closed position.



Right side drain valve with lever in opened position, with elbow and tubing attached.



Left side drain valve with lever in closed position.




I've been driving the car for a few days. No leaks so far. Seems like this is going to work.

Ed Scherer

The one remaining concern I have is galvanic corrosion: brass and aluminum are not very compatible, and we obviously have water present. I didn't research this very much, but came across one post that is somewhat comforting.

I'd welcome informed opinions on this issue.

I expect to remove these valve assemblies within a year or two to see if there's any evidence of corrosion.

skpyle

This is an interesting idea. Subscribed.




Seth K. Pyle

SeanR

Fantastic set up Ed. Thanks.

Imo000

Nice idea but considering how rarely blocks get drained, I feel the possibility to instoducing a failure point with this valve is not worth the risk.

Mongo

Mine are frozen so I fall into IMO's category until I pull the water pump and coolant all comes rushing out all over my garage floor...again.

skpyle

Rarely hell! I'm changing the coolant in the Red Witch every two years.

Yes, it is an additional failure point. I'm thinking lock-wire or something to that effect to secure the valves closed. Meaning small hole in each lever, lock-wire to something solid.


Seth K. Pyle

Ed Scherer

This really shouldn't be necessary.

The lever has to be lifted (against the force of a spring) to rotate it. It's not going to move on its own, and in the position of a 928 block drain, there's really nothing that's going to randomly get in there to lift and rotate it.

In other applications (e.g., an oil drain on some farm or garden equipment that's close to the ground where it might be snagged by a twig or something like that), I can see that the LC-10 lever lock would give even more peace of mind, but I just didn't think there was any reason to use it (especially given that the LC-10 is plastic and would be very close to the exhaust manifold).

I guess that if you're really worried about lever movement, you could just wrap a piece of wire around the neck above the lever and make sure it blocks the slot into which the lever moves to open the valve.

skpyle

Even better! I did not realize the level locked.

Good to know, thanks!


Seth K. Pyle

jcorenman

Ed,

I wouldn't rule out the possibility of corrosion. Aluminum and brass are not compatible as you note, and in the presence of conductive liquid will create a battery. The aluminum will get eaten and the brass will be protected-- not the ideal situation.

In oil (per your referenced thread) there is no problem, because oil is not conductive. Pure water is also not conductive, and would be safe. I am guessing that fresh coolant is also safe, that's one its primary jobs-- to protect against corrosion. Stale coolant is a different matter.

My personal experience is aluminum boats in seawater which of course is highly conductive, and a copper penny in a wet bilge will eat right through an aluminum hull. A brass fitting into aluminum would never be done around seawater, but this isn't seawater.

I think your approach is exactly right-- check the fitting in a year or two, and inspect the block threads carefully for any etching or corrosion.

Adk46

Nice! It's bad enough doing a full drain by the "pull the plug and run" technique, but I recently wanted to drain the system just enough to remove the water bridge - that operation is even less graceful.

The Temp II sensor has a brass body and seems to be OK in contact with aluminum and coolant - I just replaced mine which was probably in there for 30 years.

M. Requin

I installed one on the oil pan, like it a lot, makes taking samples for oil analysis very easy. Thanks to this thread I think I will put them in the block drains as well.

Petza914

I have these in all my car oil drain pans. Unfortunately, the one I had bought for my 928 doesn't fit the opening so I need to get a different one that will go in during next year's oil change.

Ed Scherer

Thanks for your thoughtful response, Jim. More motivation to change the coolant on schedule.

Good point. I had forgotten about that.

Chris Lockhart

Ed, is there a particular reason that the adaptor is needed between the block and the valve? Is it a clearance issue? I was looking at the F109N and it looks like it could just go in all by itself. Is there something I'm missing?