Yanmar 4JH3 Raw Water Pump Impeller

Aug 10, 2017
2
Perry Cutter 47 GC
Has anyone else used the relocation kit by [SeaSpaceMarine.com] to relocate their raw-water pump?
My daughter's boat requires lifting the engine and removing the pump completely just to check the impeller. So instead of repeating this process every year, I am thinking of relocating the pump now and be done with this hassle. What a pain!!!!
Would be interested in anyone's experience.
 
Jan 12, 2011
930
Hunter 410 full time cruiser
Never even heard of such a thing but was interested in seeing it. But I couldn't find in on web site you indicated so maybe a link would be helpful in getting answers.
 
Jun 1, 2009
1,737
Hunter 49 toronto
Ok
So they say imitation is the sincerest form of flattery
Well, if you look on the forums, I did a 20 page write-up on how to refit this pump to your engine.
I sincerely doubt this is a "patent pending" system
Now, I agree that mounting the F5B-9 is the way to go. I spent a lot of time engineering the solution
What this guy is leaving out is a critical part of the equation, and that is how to keep the pump from rotating.
I am not sure what he is selling, other than an aluminum plate.
And you should not remove the harmonic balancer bolts as he's suggesting
I think you should look at my previous post.

Good luck
 
Feb 20, 2011
7,990
Island Packet 35 Tucson, AZ/San Carlos, MX
That's the one!!
If you can prove prior art, that "patent pending" business from SeaSpaceMarine could be a non-starter?
Anyways, nice to read about how engineering gets done. Mother of invention and all.
 
Jun 1, 2009
1,737
Hunter 49 toronto
If you can prove prior art, that "patent pending" business from SeaSpaceMarine could be a non-starter?
Anyways, nice to read about how engineering gets done. Mother of invention and all.
So, here's the reality.
Firstly, there are lots of guys who claim "patent pending" on stuff, when there is, in fact no patent application. Basically, it's a bluff which is neither provable, or disposable.
Having designed & published this upgrade on the Hunter Owners site, I frankly see nothing remotely patentable.
Furthermore, it's not finacially viable to do so.
The pump is off the shelf, and there are many ways to mount it to the crankshaft pulley. Honestly, I find the adapter plate a poor choice, as:
Is far more expensive than the threaded stud design I documented
It mandates pulling all the crankshaft pulley bolts, which is a bad idea.
Also, the threaded stud design allows you to very easily pull the pump, and re-install it without messing around with spacers, etc.
What I find confusing is that this company didn't address the issue that the F5B-9 is designed to work with 1-1/4" hose. I am fairly confident that this won't work.
I have a Hunter 49, and my hose size is 1". It was a huge issue to consider adapting my 1" through hull fittings to 1 1/4" hose. Both very expensive, and possibly unreliable.
It took a lot a thinking to come up with the stainless BSP adapter fittings I documented in my posting.
So, I'm the first guy to admit that someone bettered my design, and endorse it. But, thus "patent pending kit" simply won't work as advertised, and that's the issue. If someone is handy enough to facilitate this upgrade, they will see the benefits of a simpler & cheaper methodology
 
Jun 15, 2012
694
BAVARIA C57 Greenport, NY
Art, I know my crankshaft pulley has one large bolt in the center, and 3 threaded 10 mm holes in a circular pattern.
 
Jun 1, 2009
1,737
Hunter 49 toronto
Art, I know my crankshaft pulley has one large bolt in the center, and 3 threaded 10 mm holes in a circular pattern.
Might work.
I suggest you get dimensions from the mfg.
I'm still not keen on removing all the bolts at once though
 
Jun 1, 2009
1,737
Hunter 49 toronto
Have tried to contact "Sea Space' . No reply. Anyone able to contact?
Ok, I'd like to fully, ( and respectfully) comment on the Sea Space pump mount.
Honestly, it's a bad way to do it, and they haven't addressed some very important issues.
If you review my original post, which was obsessively thorough, I showed how to mount the pump without pulling ALL the crankshaft pulley bolts at once. This is what I would loosely refer to as "a bad idea"
The very cool method of installing the studs does 2 things:
You can install the pump and ensure the crankshaft pulley and harmonic balancer don't shift.
And, if you want to pul, the pump for service. Etc., you just unscrew the nuts and it pops off.
BUT, what I really don't like about the Sea Space. Is that they didn't cover (at all) one of the most difficult aspects of the pump installation, and that was how to keep the pump body from rotating, while the base is spinning.
And here is where I remind you that I hadn't totally figured that out when I posted the article. You see, this is very challenging.
The pump is moving around in all directions with the engine as its jumping for joy on its mounts. The theoretical way to stabilize the pump body (which has a 5/16" threaded post), is to somehow attach a linkage arm from this to the engine surface

3 words... Good luck Chuck
The pump is way too far from the engine to fabricate anything resembling a stiff brace, and I spent more hours staring at my engine imagining how to do this, than watching the entire Breaking Bad series 3 times.
And I bent up a lot of aluminum in the process.
So, I cheated.
As you will note in my article, I mounted an aluminum angle across the engine bed, put a shoulder screw stud in the pump, and made an angle bracket with an oversized hoke that tge shoulder screw could "float" in. Yes, it wasn't a great solution, and I said so at the time. But, I didn't see anyone responding to my post (although hugely congratulatory ), saying "Hey Art, you should try this"
So my shoulder screw has been rattling around in the oversized hole, making it much more oversized, and finally reminding me quite audibly that it's time to get this finished.
So I went (solo) for an all you can eat sushi dinner, taking my McMaster Carr catalog, and a stack of paper. Now, I know what all of you are going to say...
"How did you get McMaster Carr to send you a catalog"
After an hour and 58 minutes, ( maximum seating time is 2 hours), I sorta had it.
Now, I'm really sorry I don't have any pictures to post. I blame Apple
The concept is simple. I used a compression spring interface between the pump stud and the engine bed mount. A compression spring will float in every direction, and will compress over an arc, which is exactly what you need this to do. Little tricky, but you need to cobble together some angle brackets which you can mount the ends of the springs to. One angle bracket mounts to the pump, and the other to the engine bed .
But there is one other really important thing that (a rightly selected) compression spring will do: it acts as a limited extension spring.
And here is why this is very important.
On the F5B-9 pump, (actually all pumps share this phenomena), when you shut the engine off, there is actually higher pressure on the outlet side than the input side. What this wants to do is run the pump backwards. As the F5B-9 is a 2-part pump, (versus your standard integrated pump), the rotating pump tries to rotate backwards until the pressure equalizes.
On my original version (with oversized hole) the sound and force was noticeable. So. I pre-biased the pump in the running direction by securing the outlet stem with shock cord. Very ugly,
So, by using the compression spring, it now compensates for this by floating counter clockwise very briefly when the engine shuts down. And with no banging, etc.
So, here is what I'm saying .
I you want to install tge F5B-9 pump to end your impeller changing misery, I highly encourage this. I would not ever count on changing the 4JH impeller anywhere except at a dock the way is is originally configured.
But, be aware that the spacer kit being offered is a very small piece of the puzzle, which now has a full solution.
And when I get an Android phone, you can see what it looks like.