Fischer Panda 4500ND cooling problem

stuartwineberg

stuartwineberg

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Happy New Year to all. This is my first post and thanks to all the regulars whose advice has helped me in many areas.
I have a newly acquired 2005 Hardy 36 with the above raw water cooled genset which has only 16 hours on it (after nearly three years, so well underused by previous owner). The problem started with the genset cutting out with engine overheat after 5 mins. FP advised me to remove the thermostat and blank off the bypass pipe between the sacrificial block and the exhaust. Genset now runs for 5 mins but cuts off with an exhaust overheat. Just replaced the impeller. Old one had one vane gone which I could not find.
Quirk is that used water is coming not out of the exhaust but out of what appears to be the air vent pipe at the top of the siphon loop.
Do I have an airlock somewhere or a more serious blockage. As usual access is almost impossible.

Thanks

Stuart
 
Had a similar problem with our Fisher Panda which turned out to be an exhaust manifold leak.This set off the overheat sensor and it cut out. Probably something quite different for your as our sacrificial anode block is the water inlet manifold.
 
[ QUOTE ]
Quirk is that used water is coming not out of the exhaust but out of what appears to be the air vent pipe at the top of the siphon loop....exhaust over heat...

[/ QUOTE ]

suggests the water injection point might be blocked, particularly with the low hours. If anything like the zeise we use to own the manifold / exhaust pipe was of aliminium which grew white cystals,which restricted the flow.

check impeller again as no / lowflow could wreck the new one.


suggest make a temporary disconnection at injection point and run inti a bucket. dont be tempted to inject quantities of water into injectionpoint as is easy to back flood the engine.


ps chase the missing vane as is probably in a bed of the pipe, or at a junction etc,
 
Thanks for both those responses. More likely to be David's suggestion I think. Will try the disconnect and bucket technique. There will be a delay before I let you know what happens - work beckons

Stuart
 
Update on the above. On these generators, the connection manifold (water in, water out, thermostat bypass) is also the sacrificial anode and is mounted to the engine block with sealant. Despite the manual showing the connection block held by allen screws, mine had 13mm nuts. problem was that once nuts removed, the anode block was tight to the cylinder block and I could not shift it. Short of a cold chisel and hammer I am stuck (as it is!) . The connection anode has 2 tapped holes in it, do FP have some fancy tool for pullling the anode off the block?

Thanks
Stuart
 
is that tongue in cheek ? perhaps leave nut off an warm up,remove studs if possible, clout with hammer, expect massive corrision on the joint due to disimilar metals.


attach a slide hammer to the tapped holes to help with removal, if they are in the required direction

Machine martdo some good slide hammers, or make own special version with long bolt and old 1lb weight drilled out to fit.

edit added slide hammer
 
Thanks David
No tongue in cheek intended except about me being stuck. Haven't heard of a slide hammer - do I take it it is a weight on a rod and you use it to create a percussive pull away from a surface? I'll be unimpressed if there is corrosion where the anode meets the block since the manual is full of "death and glory" warnings about how important the sealant layer is to prevent just such a problem and as far as I know it is still in the factory fitted state. I did think about trying the process when the block was warm so glad to have that idea endorsed. All this talk of large hammers has me worried. I dont want to risk cracking the block. I am starting to get tempted to get FP in to do this bit - at least if they damage something they are insured

Thanks for your continuing good advice

Stuart
 
You are exactly correct about slide hammer, coldnt have put it better.

I would suspect somebody has had it off before,particularly if the bolts have been changed.

any chance of posting pics?

as genny is out of warrenty I would suggest:-

1 if fp are asked they will suggest,Replace head & manifold all at your expense, as there is evidence of corrosion. for certain they will not be paying for the mainifold.

2 If warming by engine running with nuts etc off manifold doesnt work,

3 clean a bit of manifold away from head and smear a bit of ordinary household tablet soap ie "lux, camay etc"
on it and warm evenly with a butane torch until it goes black. this acts as a temp indicator, well away from the risk of melting. +light hammering.

4 let cool, soak joint area in penetrating oil for a week

repeat 3

4 1/2 remove head &manifold to do 4 & 3 at home

5 cut away manifold, clean head & replace manifold only.
 
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OK here's some photos. The top view shows where the water should inject into the exhaust manifold (under the label) When I took the thermostat cover off there was no water in the block.
I think, judging from your last post, this is a bit different to what you expected. The water injection point, and also the anode is the metal square with 3 pipes coming into it - I have posted a close up. The pipe on the right is the exhaust by pass which I have blanked off at FP suggestion. The two pipes at the bottom are water into the block and water out of the block. my problem is that despite removing the 4 nuts you can see in the close up I cant get the metal anode away from the block. it is held in place with sealant.

Hope that makes things clearer

Thanks

Stuart
IMG_4329copy.jpg
 
Great pictures, you are correct I thought the manifold was on the cyl head

1
the anode block on the side of the generator seems to be sweating / leaking, if so is probably badly corroded inside.

suggestion remove both the other 2 lower pipes and join them, give engine a short no load run, wont damage alternator windings as it takes a while under load to heat. have you tried pokeing wires up the 2 pipes. equally blow down them into the alternator. connect a hose to one. <span style="color:red"> BE CERTAIN TO DISCONNECT THE INJECTION POINT, THOUGH AS LARGE RISK OF BACK FILLING THE ENGINE WITH WATER</span>

after all there might be a blockage elsewhere. Highly likely to be here as water would lie here when not in use.

2 remove nuts from anode block and use to remove studs from casing and only make a few blows to side of anode block as the thin web end on the left looks as if it could be very vunerable. The slide hammer really looks a good option.

3 order new anode block to see if it is flat or registers into the casing. will also show the way for drilling out.

have you checked you can blow down the injection pipe into the exhaust, and through the other plumbing?

has the engine been run in fresh water, or sea? If fresh there will be white zinc compound (calcate?) which when dry is very hard,and of greater volume like rust, so there could be an internal lip of corrision, similar to the white covering on sea anodes on when kept in fresh water.


In which part of the circuit is the syphon vent fitted ?


sea water pump, syphon , engine & genny ? or does it break out and return in the middle of the engine water circuit ? as if the latter the problem is after the return point, in view of the leak from the vent mentioned earlier.
added post edit

disconnect pipe where seawater is delivered to engine and run for min time just to check delivery of water to engine, after all this is like a new install, but worse! may be the new impeller is allready damaged.

Is the seawater filter above water level ? if so make sure the lid of the filter is secure, but before that fill the plumbing as much as poss with water. on our second gen where the filter is above the water line we have a small piece of pipe inside the filter on the outlet so the filter remains full of water , giving the pump an initial supply on start. Think of the drain overflow in the chemistry lab sink.

/edit

The faryman engine is almost identical to the one we had, excessively expensive drive belt to the seawater pump. I converted ours to direct drive using the spindle used for the starting crank.
 
Great pictures! Had a similar problem with my 2 year old FP 4.5ND. Runs for 5 mins then stops. Removed the thermostat as advised by FP Ferndown - no change.

Removed the cooling block (anode) found one orifice almost totally blocked by a build-up of scale/gunge. Scraped this out and the metal crumbled with the gunge and left a groove under the 'O' ring and a track to the edge of the block. This would probably have leaked very soon after re-assembly so I changed it - £105 if I remember. Problem solved. After 2.5 years I thought this was a bit steep, but as I hardly ever used the gen it just sat there eating itself away! FP say you should run the gen often to stop the gunge solidifying and the metal eroding.

I bought the special sealing gunge as well - if you get a leak you may not know about it until the engine seizes! The tray fills up with water faster than it can drain out and the water is drawn into the cylinder via the air intake.

Apart from that it seems a fine unit.

DD
 
OK - hopefully a conclusion to this one. FP came to look at the unit. The most interesting thing is that the tapped holes in the front of the anode are jacking points - you wind a couple of M8 bolts in and it breaks the sealant joint, no hammering. The waterways in the anode were completely blocked. Once reamed out a surge of filthy brown water came through when we cranked it followed by clean. Anode replaced and hopefully job done. Again for interest, the anode is sitting on the generator and the water literally sloshes around inside the cooling jacket - there are no water channels. It then comes out throught the anode and is injected into the cylinder jacket. If this gets corroded it can be a bad news job as the waterways are narrow. I have some corrosion on the core plug so that might be an issue later - but for now all is well

Stuart
 
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