Kohler 5E Generator Impeller

[gerryb]

replaced the impeller on our generator over the weekend along with adjusting the choke mechanism and replacing the zinc. (Note to anyone considering replacing the impeller on this unit themselves - this is about the easiest thing I've ever done in the ER of this boat. Save a couple of hundred $$ from the dealer and do it yourself. Found the impeller/o-ring online for $28.)

take a look at the picture of the old impeller...this is with only 28 hours on the unit...! The lesson here is that maintenance schedules that call for maintenance at x hours or x months need to be followed on both counts. The Kohler tech I spoke with said he recommends replacing the impeller every year if it is heavily used, every other year otherwise. This one went four years. I did get some of the broken pieces out but I think a few may have made it down to the muffler or (hopefully) out with the raw water discharge. I take the hoses apart and inspect at the end of our season when winterizing.

The genset now has new plugs, new zinc, new oil, new filters, zinc and impeller. The choke adjustment was critical to getting this thing to not shut down when starting it.

 

[Hampton]

Good lesson and good words. Thanks.

 

[gerryb]

Had the misfortune to have to 'revisit' this issue again over the weekend. :smt021

The genset overheated when running it Sunday. While it was running, I went to quickly touch the heat exchanger and impellor housing to get a sense of the temperator... Both smoking hot. (Be careful - you can get burned touching either of these..) The impellor housing SHOULD not be very hot to the touch if water is going through it..so that is an indicator of a water flow problem.

Monday am, took the thing apart again, and the NEW impellor was shot, missing several blades and cooked from running dry is my bet. So replaced it (I always order two of everything when it comes to spares) but this time, took several additional steps that I would now say are REQUIRED when changing the genset impellor and the impellor is missing blades.

I decided to take the genset impellor and all related water hoses apart and FLUSH everything. I removed the zinc and three hose connections from the exchanger, also disconnected the hoses from the strainer. Flush water through EVERYTHING (yes you will get wet). I found most of the blades by flushing front to back, then back to front, then also flsuh the through-hull hose and thru-hull with seacock valve open to clear the gunk out of the inlet (which I'm >90% sure was the root cause of all these problems in the first place!)

Flushing technique I used was to connect a hose to one side, leading down to the bilge, put the water hose nozzle on another and manually plug the third opening on the exchanger and FLUSH, FLUSH, FLUSH. Also flush the inlet that goes to the muffler and out the side. Flush the hoses themselves and make sure there's nothing stuck in them!

Ran it at the dock for 2+ hours Monday afternoon with full load and it seemed to run great. Housing was cool as was the impellor housing. Water flow was strong. I noticed that the water flow out went all the way around the diameter of the outlet.. before the water came out only along the bottom portion of the outlet. Last test will be if it runs while boat is on plane (with less displacement pressure to assist water flow).

 

[prochaska]

Lucky me, I just had to replace my impeller sat. Gen cut out after running for 2 minutes. Service code said "LOC" (low on coolant). Just happened to be getting gas at the dealers dock and asked if someone could look at it. Tech fist checked strainer and cleaned it out (wasn't even dirty). That didn't do it, ran for 1 min then cut out. He then checked the impeller. Yep, 2 fins busted off. Pieces stuck right at the hose opening could be removed with needle nose. He happened to have one in stock. After he was replacing the last bolt, he informed me that it is not covered by warranty. The genset only has 2 hrs on it!!! :huh: "Put it on my account".....Oh well, still waiting on the bill for this one. Gen now runs and can charge the little ones Nintendo DS video game in the middle of the lake!

 

[skolbe]

Prochaska - How long have you owned this boat. What make and model is it?

 

[prochaska]

This is on a 2007 260DA with 39 hrs.

 

[Stray Cat]

This is on a 2007 260DA with 39 hrs.

If the seacock is accidently closed or if the generator runs for a short period with little or no water flow, the impeller is toast. I've also witnessed what the impeller goes through when you jog the starter. As the engine coasts to a stop, it doesn't always come to a complete stop, sometimes it will counter rotate a few degrees backwards before coming to a dead stop. During that transition, those little rubber vanes must fold themselves over to counter rotate. The process is repeated when you crank the engine again. This year I managed to run the same impeller all year, I feel blessed!

 

[boughtabouy]

Good thread guys. Can you tell me where the zinc is on the 5E?

 

[Hampton]

Good thread guys. Can you tell me where the zinc is on the 5E?

When viewed from the side with the oil fill/drain, it's up on the bottom, left of the heat exchanger, right in front of you in plane view (unless the genny is blocked). In this pic, see that eye-hook on the very top right? Go down and left. The circle represents this end of the heat exchanger. The fitting at 7 o'clock on that circle is the zinc.

http://www.maesco.com/products/kohler/kohler_gas/G2058.pdf

 

[firecadet613]

The choke adjustment was critical to getting this thing to not shut down when starting it.

How did you adjust the choke?

 

[gerryb]

The choke has an electrical and mechanical control mechanism. The mechanical part os adjusted by increasing/decreasing the torque pressure on a spring which acts to shut the choke. It is in the front/left of the gen set if you are looking at the control panel. I'll see if I can get a picture or a link to a manual and directions but check your manual as I think it is shown there.

 

[firecadet613]

I think I've got it figured out. Undo two screws, and gradually turn the choke actuator a bit.

 

[Stray Cat]

I think I've got it figured out. Undo two screws, and gradually turn the choke actuator a bit.

You're on the right track, read through this post: http://clubsearay.com/forum/showthread.php?t=3101&highlight=choke

 

[Big Billy]

Another point to add here is to change that zinc every year, book says 35 hours. If you wait, it will break off from the brass nut, then you have to pull the exchanger to getr the rest out, well worth doing every spring....

Billy

 

[firecadet613]

Any other good 5E tips for us new 5E owners?

 

[Hampton]

Any other good 5E tips for us new 5E owners?

Run blower for 4 minutes - Check for gas fumes where blower exhaust exits - every time
Start genny and check for good water flow
Leave blowers on
Warm up for 1 - 3 minutes, depending on water/air temp
Turn on genny breakers
Turn on high power items first
Run loaded up - A/C or water heater plus battery charger/refriges
Turn off electrical items
Cool down genny for 1 -3 minutes depending on temp and recent loads
Turn off blowers

Check oil often, change in accordance with the books
Change impeller IAW manuals - At least every year on genny
Change zinc IAW your zinc's wear patterns. More often at first, then as required.
Keep mechanical controls on top well lubed/protected. I sprayed the whole area with white lithium grease a couple of years ago. That has worked great.
Check the coolant level often. Mine is very low in the reservoir when cold.

USE THE DANG THING - OFTEN!