L120 Injection pump (from water pump thread)

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RT Firefly

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Greetings,
Mr. Rick B. You raise a valid point regarding stripping threads. As you will notice in Mr. Marins picture, the drain plug is on a small raised portion of the pump casting. As I recall, it's a 1/4-20 bolt. Ideally one would pull out the bolt and as you suggested install a banjo fitting but with a 1/4" opening to start with it's be quite slow. (Ya, I know, impatient)...
What I would like to do is take off the injector pump, drill a substantially larger hole (1/2" to 5/8"), thus destroying that raised portion as an unavoidable result, tap the hole and THEN install an elbow or banjo fitting.
Really, I think the ONLY safe and sure way to accomplish this is to remove the pump and use a drill press. I am VERY hesitant to do this for a number of reasons so I suppose I'm stuck with one of the many suggestions offered for making the oil change easier and less messy. I have attempted most of these and I've not had much success.
I think this has been covered before and I apologize for my early onset Alzheimer's.
 
RTF--- Several people on the GB forum have fitted drain devices to their FL120 injector pumps. BUT.... they all have the stock raw water system with the Lehman coupler and Jabsco pump. This setup provides sufficient clearance below the injection pump for a drain fitting and valve.

It's only when the Johnson pump is fitted that this clearance goes away. Over the years this subject has come up again and again on the GB forum since a very high proportion of FL120 owners on that forum have long since fitted the Johnson pump. There have been all sorts of ideas of fitting nipples and hoses and valves on the hoses and banjo bolts and little 90 degree elbows and on and on and on. And in every case so far, the person finds that whatever their plan was, it wouldn't fit. Even Bob Smith warned me when we converted to the Johnson pump about the minimal clearance between the upper pump outflow elbow and the drain plug and that it was the nature of the beast. His son Brian was the one who told me about canting the pump which would provide a bit more clearance for removal and installation but that it would still be very tight quarters.

I'm sure if someone came up with a practical and workable drain fitting solution a lot of people would be grateful. But I've not found the setup we have to be at all inconvenient with the solution we came up with, and everybody else seems to be able to deal with it just fine one way or the other. So to me it's kind of an academic issue.

One of those "it would be nice if we could but since we can't it doesn't matter" things.
 
Greetings,
Mr. Marin. From your picture and from what I foggily remember I've got a goodly amount of space directly under the pump but unfortunately, as you and others well know, it's what one could call "captive" space. Meaning there IS space but no room to get any container into or out of said space hence the use of tubes, ramps, diapers (the let it drain into the pan cadre) or other devices.
I don't think one could enlarge the existing drain hole too much because of the size of the "small raised portion of the casting" as I mentioned above unless you machined off the raised portion and re-tapped right into the body of the pump. This would entail removal and dis assembly of the pump. Quite the daunting task and one which I am not capable of performing as I have lost access to a milling machine.
Does anyone know if there is a blowup or diagram on line for either a Simms or a Mini Mac? Thanks
 
RTF--- I use a section of water hose, the kind with the colored threads. I think it's 1" hose. In any event, the outside diameter is a snug fit into a one of those 12 oz (or so) plastic juice containers you can get at 7-11, etc. I cut the "top" off the first two or three inches of the outer end of the water hose so what is left is a "trough" of sorts. The trough fits between the raw water pump and the underside of the injection pump.

Because the hose has a permanent curve in it from being kept on a reel in the store, I conform this thing so the curve conforms to the engine. So upper end curved into the engine, lower end with the bottle curved down.

Remove the drain plug, the oil comes out into the trough and immediately flows down into the rest of the hose which is attached (by friction) to the juice bottle. The oil flow is not fast enough to overflow the trough as long as the hose is slanted down. The juice bottle is a little bigger than the capacity of the injection pump.

Once the oil is drained out of the injection pump I put a new washer on the drain plug, reinstall it, and Bob's your uncle. (Or Bill, Sam, Edgar, Harpo, etc.)

I drape a rag over the top of the water pump to catch the bit of oil that gets past me as I'm sticking the trough under the drain hole after removing the plug. So no mess, no fuss, life's wonderful.

Easier to understand with a photo than a description but I don't have a photo so the above will have to do.
 
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Greetings,
Mr. Marin. I understand quite well-good description. There's not too much problem with the port engine but even with a 730 cubic foot ER, the starboard engine is still a skinny, two elbowed, three handed, three wristed dwarf job and it's a 50/50 shot as to whether or not I spill oil. I hate spilling oil hence the question as to use the Reverso oil pump or not. I might even be tempted to try to go in through the overflow hole.
 
There is a lot of "stuff" inside that pump. We have the service and parts manuals for the Dorset/FL120 and I've glanced at the illustration of the innards of that pump. Scary, and I can understand why it's the single most expensive component on the engine and a proper overhaul costs a good $1,000.

I would be surprised if you could even get a hose down to the very bottom of the sump from anywhere up above but you never know.

We have a big battery box in front of each engine so getting around to the pump on the starboard engine is "just" a matter of putting a lawn chair mattress we keep for this purpose over the battery box and engine stringers and curling around the front of the engine. It's actually reasonably comfortable to lie that way and I can use both hands to change the pump oil.

The port engine is, as you say, a snap.
 
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All this talk of a drain fitting has motivated me. I am still thinking from memory (bad thing to do) that there is enough room under the inj pump with my Johnson pump rotated to install a fitting. I have the 3/4 inch fittings on the Johnson (pump)so maybe that will give me the space I need.
Whenever the weather breaks here in Ct I plan on trying.

What I use for oil changes is a flat plastic pan with w spout that the previous ower left aboard. It works very well, easily fits under the pump. If I am coordinated enough and don't get the dropsies removing the plug (rare) I can do the job without spilling.
 
Greetings,
Mr. jleonard. From MY memory (poor) as well, I think there's plenty of room beneath and around the drain plug. As I've tried, and believe me I've tried, there's just no way to get a sufficiently large recovery vessel into and out of that space without spillage.
ONE, and possibly the MOST significant problem as I see it is drilling the existing hole larger. I would HAVE to take off the water pump in order to get a "straight shot" with a drill and when hand drilling there is ALWAYS the possibility of going off square. Then there's the maximum limit I could drill out on that "tab" the drain plug is fitted into. I'd still have to have enough flat surface left on the tab to effect a seal of the Al/Cu gasket if using a banjo fitting.
Just had another thought....If I mill off the tab, the actual case of the pump may not be thick enough to re-tap....
Oh, and the dropsies (common).......hahahahaha
 
Personally, I would never drill into the pump unless it was off the engine and "opened up" so I could see exactly where to drill.
If opened up I would look to see if the drain hole could be drilled into the side rather than the bottom (for accessibility). 1/8 NPTF if it would fit, 1/16 NPTF as plan B, loctited in place. (With NPT, no need for a "spotface" to seal on.

(That said I hope I never need to take the pump off.)
 
Greetings,
Mr. jleonard. I agree 100% although as far as access goes, once the appropriate alteration is made, access would not be a problem.
 
L120 Injection Pump

One of my fellow CHB owners solved the injection pump drain problem by manufacturing an adapter fitting which provides for installing an angle ice maker valve in place of the drain plug. With a short piece of tubing off the valve, one is able to drain the pump into a container w/o drips, runs, or errors.

The adapter fitting was machined out of a piece of brass 9/16" hex stock. The fitting is male threaded to M8-1 to fit the pump and 1/8" NPT to fit the 90 deg. ice maker valve. The arrangement can be installed with the old or new raw water pump. In some cases the valve handles must be bent or shortened to allow clearance with the raw water pump.

Approximately thirty of these units have been installed on L120's w/o any problems.

I was fortunate to obtain one of the manufacturer's last adapter fittings this fall but I have not yet completed the installation. I will do so before this summer's trip to Alaska. I am looking forward to the simplified process.

Norm
'76 CHB 34' Tri
Mitkof Isle
Poulsbo, WA
 
That would be a nice modification to make, particularly since there seems to be no "off-the-shelf" fitting that works with the Johnson pump installed.
 
L120 Injection Pump

Hopefully these images will come through ok.

The adapter fitting is similar to the reducer shown in my first image. The male threads are metric M8-1 and the female threads (not visible in image) are NPT 1/8.

http://images.grainger.com/B376_36/images/products/250x250/Brass-Pipe-Fitting-6AYX6_AS01.JPG

The ice maker valve is as shown, however, the valve shown in Firefly's post looks to be a possible option as well.

http://www.homedepot.com/catalog/productImages/300/84/8437e2f7-d0d3-4019-a7e0-7e799a3b8d72_300.jpg

I have to give credit to Ken Buck for developing this improvement. Ken recommends the use of a thread sealant (Permatex etc.), especially if the pump threads are worn.

Norm
 
Greetings,
Mr. mit. MANY thanks. I'll definitely look into that. From my vague memory the plug was 1/4-20 (determined by eye only) hence my comment in one of my first posts that I'm afraid the opening in a 1/4" fitting may be too small.
 
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