Fischer Panda Generator Bearing Replacement

With this post, I want to advise readers that to do as I have done will probably void your warranty. However, if you are out of warranty, then this is a possible solution. Normally to replace the end bearing would require the complete removal of the engine from the case. Here's how I did it.

Completed job with signs of old bearing overheat.

I discovered that my generator end bearing was making a noise and looking at the end plate, discovered some over heating signs. Time to replace the bearing!

You can see here to the left, the photo shows overheating at the center of the alternator end plate. The brown color is burnt grease which has escaped the bearing. Actually the photo is the completed job before the sound case was put back . However, the "burnt" sign were still visible.

The first thing I did was remove the centre bearing support, on the alternator end plate.

Dry bearing

This required three screws to be removed and longer screws with the same thread placed into three threaded holes on the end plate. By tightening these longer bolts, they pushed the center plate out. You can see three threaded holes in the picture to the right, and three scuff marks where the three extraction bolts pushed up against the end plate to help drive out the center piece.

I modified a puller to fit in the space available, to try to extract the bearing. In the end, so much force was applied, that a foot on one of the legs of the puller broke off.   Soooo, time to remove the end plate and put a heavy bearing puller on it. You can see the sealed bearing has lost it's ability to hold it's own grease.

Trying to remove bearing without taking end plate off.

Engine mount cut in half to facilitate removal. Assembly under way

However, in removing the end plate, I discovered that the engine mount had to be removed, so that access to the bottom last four nuts, could be accessed. However. the engine mount couldn't be removed unless the engine is raised out of it's casing. Something, because of it's weight, would require me to make a gantry to lift the generator. I elected instead, to modify the end of the casing, (seen in photo to right) which allowed me to cut the engine mount in half, which then allowed me to extract the engine mount in two pieces, which then allowed me to remove the final four nuts to remove the end plate.A crow bar(s) was used to support the generator casing while the work was undertaken.

The end plate was removed, and I tried another very heavy duty bearing puller, to no avail.

Protection for windings etc against fine metal dust

Now I was faced with cutting off the bearing with a Dremel. The end plate has a step on the inside surface which fits snugly into the generator casing. The end plate required several screw drivers, wedged in from the side, to get it started; and then I used a crow bar once a gap had been made, to pry it off. Be carefull not to damage either the end plate or generator casing. Use all your levers near the studs that remain on the generator casing, because that is the strongest area.

Bearing installed and generator case end cleaned and repaired

Cut bearing.

There are many methods by which you can get  a "stuck" bearing off it's shaft, but the most popular method seems to be with a Dremel with a cutting wheel, to cut the bearing off the shaft. Usually you cut through the bearing "almost" through it's thickness, and drive with a hammer , a cold chisel into the cut, to help fracture the bearing, and then it is usually easily removed with a couple of screwdrivers. It helps if you make two cuts with the dremel. The first cut weakens the bearing inner race and the second (at 180 degrees to the first) allowes you to 'fracture' the inner race on the shaft.

The outer shell of the bearing and the ball race were very easy to cut off. The inner race was placed next to a shoulder on the shaft, so I couldn't get the dremel saw all the way across. So, I turned it 90 degrees and cut down as far as I dared; starting near the shoulder and working back. It was  tedious, but did a slightly better job than using a grinding stone.

One jacket end cleaned; nine to go.

 After the old bearing was removed, the surface was cleaned up with a sanding wheel using the dremel again. The new bearing was driven onto to the shaft using a drift punch against the inner shell, ensuring it went on square, and knocking alternatively, from side to side.

Now it was time to clean up the surface of both the end plate and alternator casing, for the new casket. However, I found Fischer Panda had epoxied the ends of the water jacket in the casing; placing first a thick gasket like cut out, inside the water jacket, and then the epoxy to the end of the water jacket.

I found one water jacket with nothing in it, but the remains of the epoxy. I proceeded to clean all the water jacket ends and release the epoxy "bungs".

Previous to this job, I had removed my sacrificial anode and found two of the gasket cutouts blocking the water hoses that are involved with the cooling. I wondered where they had come from, and Fischer Panda advised they were from the end plate gasket. Rubbish, The gasket was complete! Now I know. I've also found in the past, some of this epoxy in my heat exchanger. No wonder I've had over heating problems in the past.

Now in cleaning up this epoxy, I found a number of the cut outs had migrated into the water jacket. Lucky I have a special took for grabbing stuff in tight places.

To the left, some of the cutouts and epoxy removed. The smaller bits were not saved

Building up water jacket with J-B Weld

 After cleaning out all the water jackets, I had to build up some areas. The areas of concern were soft aluminum and I used a dremel burr to clean away the soft stuff. Pretty much like a dentist might clean out tooth decay. Because I was not in a position to now order a whole new generator casing, I decided to do a patch job and hope this will last another year, until I can either get the new parts, or a new generator altogether. All the corrosion was at the end of the generator casing, and I suspect the epoxy had some part to play in this. My theory is that when the generator casing was raw water cooled, that the epoxy "traped" sea water and prevented an exchange of clean water, when I did a fresh water flush at the end of each generator run.

I used J-B Weld to build up the "decayed areas", after ensuring the surface for the epoxy was clean and free of dust and "soft" aluminum.
 J-B Weld takes about 4 hours to set and 24 to really harden. Selley's also has a similar product, but it sets in 3-5 minutes according to the directions. However, after trying it on another item, I found I only had about 1 minute of working time. I preferred the longer working time, although I often waited 20 minutes before applying J-B Weld to the surface.

The end of the casing, after the J-B Weld had hardened over night, was leveled with a dremel and fine burr, and checked with a straight edge.

Finally, after all surfaces were cleaned and checked for "Flatness", I used the supplied gasket and applied a thin layer of RTV high temperature gasket cement to both sides of the gasket. All studs were also given a coat of "antiseize" before the plate and nuts were applied. A gentle tap around the outer surface was required because of the shoulder that recesses into the casing. This can be seen in the inside of the gasket to the right.
The nuts were finger tighened, and the RTV allowed an hour to set up. Then final tightening done after the RTV cement had set up.
Engine mounts were applied and the capcitors and air intake module replaced. These were removed to facilitate the job and obtain exposure.
The small piece of generator casing cut out so that I could cut the engine mount in half was placed back with a small piece of aluminum plate, pop riveted to the fibreglass cutout, and screwed to the remaining sound proof case.
The engine and generator case were then filled with fresh water and antifreeze and bleed of all air. This took some time before the correct flow of water was to be had.

I feel that if I had of changed my generator casing to fresh water cooling sooner, that maybe this "corrosion" might not have happened. Regardless, while it was sea water cooled, the anode never deteriorated from it's new condition and feel FP's anode let me down. You can read about how I changed the water cooling here, so that both the generator casing and the engine, enjoyed fresh water only and heat exchanged through a heat exchanger.

Now it's a question of will this repair last a year until I can do a complete alternator casing changeout, and also, do we repair or install new? We have done four hours on the generator, and so far no problems.

Heat Exchanger Modification

After installing a new heat exchanger for our Gen Set, we had no further issues. However, the primary issue of "stuff growing inside our heat exchanger" has not been resolved, and, because the Fischer Panda generator has it's heat exchanger in such an awkward place to service, we decided to modify our new heat exchanger so that it can be cleaned out with the minimal of fuss annually.

  We took our heat exchanger and removed the ends by "unsoldering", so that new ends could be attached that would allow for easy removal.
We attached some brass ends (by soldering) with a reducing thread and then used a threaded cap, and finally a threaded tail to give us our 19mm hose fitting.

In the picture to the right, you can see how easily it is now to remove the end caps to clean the internals of the heat exchanger. And with it's new mounted location, we should no longer have issues with our Gen Set shutting down to over heating.
Since we have been dealing with heat exchangers, we have learnt something. Heat exchangers made from copper and nickel last a lot longer than those just made from copper. All heat exchangers should have some provision for cleaning the "internals". A sacrificial anode is a must. A fresh water flush through the engine and heat exchanger before turning the engine off for prolonged periods, increases the life of the engine and heat exchanger.

Heat Exchangers; Somethings to consider for cruisers

For most people traveling in "well to do cruising shores", usually have the means to obtain spares quickly. There are some areas though where spares are hard to get, or if freighted in, present customs difficulties; let alone the cost of it all. So, most cruisers carry what they think they will need. We thought we had most areas covered, but when we arrived in Fiji, we had three of our four heat exchangers go bad in less than one month. The transmission heat exchanger had small pin holes which leaked sea water. This was easily fixed with some solder. The main engine heat exchanger presented itself to my wife and I, by us noticing we were loosing engine fresh water from the "small top off tank". We suspected the fresh water was being lost through a hole inside the heat exchanger to the seawater side. Fortunately I had a spare main engine heat exchanger and replaced it out. The old one was sent for cleaning and testing and our suspicions were confirmed by the engineering firm. A small leak inside the heat exchanger.
(BTY, we hunted for a heat exchanger of any kind and could not find one in Fiji. We knew there would be some place that had one, but we felt we were chasing our "tails". So we went to plan "B". Get one where we know we can source one. Read below.)
The last heat exchanger was on the generator. A Fischer Panda (FP).

You will notice the round heat exchanger, under the motor and bottom hose. Just looking at it, I figured that it is going to be one hell of a job to get that out. We reversed flushed the heat exchanger, and got out a handful of particular matter. Inquiries, told us that this stuff actually "grows" inside and even though we fresh water flush the generator after each use, (flushing out the seawater from the heat exchanger) this wasn't enough to prevent stuff growing and blocking the tubes inside the heat exchanger. The flush worked for a while and the generator ran for some weeks, before it started to over heat again.
So, leaving the FP heat exchanger where it was, and removal for a time when we are in a better location, I decided to install another heat exchanger, out side the casing, and one which I could easily get to the hoses and heat exchanger itself. My wife was making a quick trip back to New Zealand, so I had her procure through contacts, a heat exchanger. This was modified with the appropriate hose tail size to fit the hoses used on the FP. I was very lucky to have someone help me with this while I sat in Fiji. Needless to say communication was a major factor in getting this done. Many thanks to Charles Webster.
When, the unit arrived, I set about modifing the cooling system for the new heat exchanger.

The parts, were carefully checked to make sure I had everything. The 19mm radiator hose is not shown in the picture but I had 4 metres of the hose.
The fresh water and raw water side of the FP heat exchanger were identified  and the existing hoses removed from the fittings at the appropiate end. ( the other end was left attached to the FP heat exchanger, making for an easy reversal if needed.) New hoses were run to the outside of the FP casing, by which I had to drill 3 new holes in its base. The new heat exchanger was mounted to a cross member that sits behind the FP and in front of the main engine. The hoses were hooked up and the generator started. I'm pleased to report that the generator now runs for some hours and the water from the exhaust is no longer very hot but is warm to touch and the unit no longer shuts down itself due to over heating.

Some things to consider. I knew the FP heat exchanger was in poor location and if I ever get it out, will probably put removable end caps on it and mount it outside the sound proof casing just like the new one.
The new one works great, but in the next time the boat is laid up, I might also remove, (and now very easy to do so) and have it modified with removable end caps of a screw off nature.
I'll carry more heat exchangers as spares.
I'll carry a propane torch, easy flow rods, and silfos rods. Solder and soldering iron I already carry.
I will always consider the cost of an airfare to be part of my spares, to procure the item I neglected to have the foresight to carry.
As a bonus, the FP now shuts down from the control panel quickly, and I may remove the second solenoid modification, detailed in a prior blog, because it is not needed and the whole issue of not shutting down may have been due to a protective system in the control module. I'll give it another couple of months yet to see if all is well with the shut down. How do your heat exchangers look? Can you clean them easily? Happy cruising!

Generator Shut Off Mod.

UPDATE
See below for original shut off mod.
We have in fact removed this mod. The main cause of the generator not shuting down was it has a protection circuit to protect itself should it slightly be overheated. Once you push the shut down button, it would continue to run with no load to help itself cool down before shuting down. In addition to our heat exchanger being clogged, we found some gasket material behind the sacrificial anode which bolts to the side of the generator casing seen bottom left on the photo to the above. This clogged the hose delivering water to the heat exchanger. The generator also has a high temperature shut down protection and it was after replacing the heat exchanger we had a high temperature shut down and that's when I found the additional blockage. The gasket material comes from the gasket on the end plate of the generator housing. I have a new gasket ready to replace for next season. The generator has raw water come via the RW pump and goes through the generator casing before going to the heat exchanger to pick up heat from the fresh water cooling from the engine. New Fischer Panda's have the cooling of both the generator housing, and the engine, cooled by fresh water and the sea water just passes through the heat exchanger. Due to potential corrosion I will be changing my FP next year to reflect the way FP now does it's cooling. Keep a watch out for that blog around April 2013.

Generator Shut Off Mod 2011
We have a Fischer Panda Generator  that has for some time had a shut down problem. i.e. It won't shut down from the control panel. A careful  inspection of the shutoff solenoid found no issues and the problem only presented when the unit had been running for some hours. In frustration, I used the valve at the fuel manifold to eventually have the generator shut down by starving it of fuel. However, because of the location of the valve, this would often take 5 minutes or there about. A new shut off solenoid was over $200USD and was no guarantee that it would fix the problem (it could be an electronic control module issue). Here's what I did.
I procured a fuel/gas solenoid valve off ebay for about $30USD and inserted it between the secondary fuel filter and the units own shut off solenoid. That is marked in the above photo with some red wire rapped around it.

The picture to the right shows a close up picture of that shut off solenoid.

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There was not much room to mount the new shut off solenoid. The whole unit is encased in a sound proof  casing. I had to find a convenient location to mount the new unit. I used an area just under the existing solenoid, with the intention that if it didn't work, I could reverse everything back to the way it was. The unit was secured with cable ties and with a strip of rubber to prevent metal to metal contact and abrasion. I had a spare switch for this solenoid on a switch panel and wired that in to activate/de-activate the unit.

The picture to the left shows the finished installation, and while it could be a little more aesthetically pleasing, it is fully functional. ( After all, I'm in the Pacific Islands, where nothing is available to complete some projects). the generator now shuts down in less than 5 seconds when the solenoid is turned off. I suspect the OEM part is faulty  but who wants to pay over $200USD to fix that.
Cost; $30USD for the unit. Fuel hose and hose clips and wiring, I carried as spares. About 3 hours work.