Suzuki DF6 cooling

[DownWest]

Following the other thread, I thought it better to start a new one. After cleaning the carb and jets, the engine ran fine. But no cooling dribble from the back. Stripped the bottom end and found the impellor a bit rat eaten but not enough(IMHO) to stop it working. Damage was from scale lumps. I think the engine has spent a lot of its summer time in the water, 4 yrs old and lives in a well.
Question is: anybody know of any other part in the system that might fail? Is the damage to the impellor enough? New part arrives tomorrow or thursday. Just trying to keep ahead as it my first look at this type of engine.
Andrew

 

[VicS]

Checked that the tell tale is not blocked?

While you have the gear case off connect a hose to the water tube and make sure you can get a good flow..probably have to also remove the thermostat.

Inspected pump internally for damage eg scoring?

Old impeller sounds well past it. They don't work once the rats have chewed lumps out of them.

 

[DownWest]

Thanks Vic,
The casing is OK after I scraped the scale off. The water test up the tube is to be tried tomorrow morning. Any idea where the thermostat is? I thought the tell tail was independant of this. First idea (from reading like threads here) was to clean the tell tail. There is a plastic plug (clean) and another hole closer to the leg, also clean. The rodent attack on the impellor has left notches out of it, but the end faces are more or less intact. When we tried it on the water, after a very stern down launch, there was a trickle from the tt. But this quickly turned to steam (20sec) from the plastic plug. There is no history on the engine, but I think mostly fresh water use. Otherwise looks in v good condition.
A
Busy day (not the engine!) so off to bed. Will look here tomorrow am--A

 

[VicS]

If the impeller has chunks chewed out it has definitely had it. It has to seal top and bottom as well as on the vane ends.

the thermostat is located in the top of the cylinder head #17 HERE

The reason I suggested removing it is because you might not get a flow of water from a hose through the engine while its in there and closed.

But if what you have seen looks Ok and based on the description of the impeller once that is replaced you will probably be sorted.

The plug next to the telltale is where you can screw in a flushing connection for a hose ? Or does it screw in in place of the telltale?

 

[DownWest]

Vic, brilliant help with the diag.
The plastic plug has a hole in it and is positioned under the exaust area, while the other hole is at the top of the leg above the mounting swivel and angled 45 deg down. The top and bottom faces of the impellor are good as is the contact line at the tip, the lumps out are where it bumped over the scale. I expect this is the proplem. Going to flow test the system after the cuppa has sharpened up my intellect.
A

 

[VicS]

I hadnt realised that I'd not given you the link to the parts diagrams before.

I expect you have noticed that if you go to "Microfische parts lookup" at the top of the left hand index you will be able to locate similar exploded diagrams for all the other sections of the engine.

Not a substitute for a workshop manual but very useful at times.