Changing impeller in diesel generator

[rchilds]

I recently bought a 2004 Marlin 300 with a Fischer Panda 4200 diesel generator installed in the stern. Does anyone know how to get to the back of the generator to change the impeller? There is no where to stand in the bilge and the small access door is too small. If I remove the entire door and panel, I think that I could lie on a piece of plywood and possibly get to it. Does anyone have suggestions?
Rick

 

[Fishtales]

You will have to remove the panel and maybe even some of the mounting bolts. It is a tight fit to do just about anything on it. I've never had to do that.
Good Luck.

 

[HMBJack]

How small are your hands?

When I did mine, it was like this:
1. remove the deck plate to allow more room to get down in there
2. remove the sound insulation covers
3. reach waaay back - down and to the right - and locate the impeller housing
4. remove the small hex nuts on the impeller cover (actually wing nuts but I changed mine to hex)
5. go to your HW store and buy many more of these hex nuts - I recall them being metric
6. remove and replace the impeller
7. re-install the impeller cover. You should fully expect to drop several of the hex nuts (see #5!)
8. re-install the deck plate from #1. Seal with GE Silicon II caulk in "almond" color for an exact color match.

Not hard - just a little frustrating. Step #5 is veeery important! Good luck!

 

[georgemjr]

I removed the entire access hatch. Then had to lay with my chest on top of the generator, head hanging over the back to barely get to the impeller (quite uncomfortable). The cover to the impeller is held on with 4 wing nuts. Hard to reach, very easy to drop (which I did). I have read that it is much easier to put it back together with regular hex nuts, placed in a box end wrench that has a small piece of duct tape over one side of it to hold the nut in place and keep it from being pushed out the back (probably easiest with a rachet wrench). It is as tedious as you could imagine, but not overly technical or difficult. I retrieved the hex nut with a clothes hanger (since it is stainless and couldn't be picked up with a magnet) Yes I could just buy a new one (which I did) but I am too anal to leave the dropped one in the bilge.

 

[wspitler]

Fischer Panda has replacement studs that hold the impeller cover on that have a very small female allen wrench insert on the outside end. You can insert a small allen wrench into the end of the stud, slip a hex nut over the allen wrench and use that to get it started on the stud. You can actually use wing nuts just as easily with that set up. Once I got the special stud, I didn't drop any more nuts into the bilge. Not fun though.

 

[Meanwhile]

Can someone take a video of this process so we can enjoy some popcorn? I need to do this and I'm not looking forward to the spectacle. I'd take a GoPro but from the sound of it, it may not fit in the space while I'm trying to fit in there and I'm swearing at the Panda.

 

[Off the Hook]

What is the recommended number of hours to replace the impeller?

 

[Meanwhile]

Off The Hook, did you mean to ask the number of beers to change the impeller?

I tried to change it today, and now I understand. I'm not yet finished. I did have to run and buy more wing nuts, and need to locate a flash light to find the now missing wing nut. They are M4 by the way. I'll get a 12" wide board to lay and wiggle into the bilge. I tried putting my feet in the bilge and contorting to reach the wing nuts, but that was not possible for me. Who the heck decided to put the impeller in the rear of that machine, or in the front and mount it backwards?

Is there a rubber O ring? My kit has one in it but I cannot feel one. My kit also has a thin paper gasket, are others using that also?

I will survive the next attempt tomorrow afternoon. I'm going fishing for Springer chinook in the morning, in another's boat.

Randy

 

[Angler Management]

Randy, any luck with the blackmouth? I'm headed out next weekend.

Off The Hook: My understanding is these impellers aren't as beefy as some of the other, larger, diesels. I think most users replace them when they fail after several years, I think a two year schedule is probably sufficient. I'm replacing mine annually because I don't want to have it fail when I need it. I'd rather repair it in my driveway rather than while on a trip. But I'm kindof a worry-wart.

RC