Perkins 4108 coolant replacement....bleeding the system?

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Suffolk Punch

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Many apologies, I am once again asking for advice....
I'm once again travelling up from sunny Suffolk to Newark Marina this Saturday to visit my boat and change the anti freeze/coolant in the ol' Perky 4108s (with heat exchanger cooling system).
What I'd like to know is, do I have to bleed the system whilst filling and what the procedure is, or is it enough just to fill the system slowly and massage the rubber hoses to expel any excess air?
Sorry for so many questions :confused:
 
Calorifier? No need to bleed standard engine just fill and run, check level frequently until warm. Do not completely fill the system as water expands when hot but liquids will not compress therefore leave level approx. 25mm below full to enable an air buffer against the expansion of the liquid.
 
All I do, is undo the drain plug of the heat exchanger near the exhaust outlet then remove filler cap, poke a wire or cable tie up there to dislodge rust scale, after that's stopped running do the same to the drain plug on the port side of the engine block.
To fill replace drain plugs pour in as much coolant as possible and start engine, keep an eye on the coolant level and when it starts to go down, replace as necessary when it stops going down, replace filler cap. Job done.
 
PlankWalker said:
All I do, is undo the drain plug of the heat exchanger near the exhaust outlet then remove filler cap, poke a wire or cable tie up there to dislodge rust scale, after that's stopped running do the same to the drain plug on the port side of the engine block.
To fill replace drain plugs pour in as much coolant as possible and start engine, keep an eye on the coolant level and when it starts to go down, replace as necessary when it stops going down, replace filler cap. Job done.
Click to expand...

50/50 mix is the normal ratio recommended by Nanni & Beta
 
I've got a drum of concentrated antifreeze/coolant and 10 litres of distilled water. Had planned to mix at 33% antifreeze and yes I do have a Calorifier and I presume that will make a difference to the amount I put in (on one engine anyway).
So does the procedure for the Calorifier engine differ to the other engine other than needing more coolant?
Thanks very much for all your help...a steep learning curve here.

Dan
 
Suffolk Punch said:
I've got a drum of concentrated antifreeze/coolant and 10 litres of distilled water. Had planned to mix at 33% antifreeze and yes I do have a Calorifier and I presume that will make a difference to the amount I put in (on one engine anyway).
So does the procedure for the Calorifier engine differ to the other engine other than needing more coolant?
Thanks very much for all your help...a steep learning curve here.

Dan
Click to expand...

As sailorman says, the "standard" dilution is 50:50 but 33:67 should also be fine for UK winters and the corrosion inhibition is effective at that concentration.

The calorifier shouldn't make any difference other than to the volume required. Both my engines have calorifiers but the coolant change process is normal. Once the new coolant is in run the engine and feel the inlet and outlet caloifier hoses where they leave the engine. You should feel first one getting warm and then the other one.

There is always a possibility of an air lock with or without a calorifier but these usually blow through as the engine warms up so you always need to keep an eye on the coolant level until everything settles down.

If you do have an airlock which doesn't blow through you can usually solve it by clamping hoses for a short time to force coolant through where the airlock is or, indeed, by pumping/massaging the hoses as the engine runs.

Richard
 
Ok, I went up to the boat today at Newark armed with tools, antifreeze/coolant, 10 litres of distilled water and knowledge and advice gleaned from this thread :)
So decided to do the port engine first (the one heating the calorifier). Drained 5 and a half litres from it, pretty cruddy so well due for a change of coolant. Flushed it a couple of times to clean it out and got 3 litres back in.
Massaged the exhaust manifold coolant hose and the level dropped a bit more so fired the old donk up with the heat exchanger cap off and topped it up as the level dropped. Finally got 5 and a half litres back in and the inlet and outlet hoses to the calorifier getting nicely warm (I'm presuming this means system has bled successfully?)
Checked for leaks and shut it down.
The starboard Perky wasn't quite so accommodating when I went to refill it, and though I fired it up and let it run it wouldn't bleed until I shut it down and removed the rear bleed plug at the back of the head and then the one at the front of the head. Got five litres out and five back in so again presuming that everything is hunky dory :encouragement:
Oh, and I went with the general concensus on here and did a 50/50% mix of coolant and distilled water. So thanks everyone who gave advice, I feel a bit happier knowing that my venerable old donks are protected for the winter :)
 
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