Any experience flushing the heat exchanger on a Perkins 6.354?

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tillergirl

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The coolant is a bit murky and is loosing a little via the Header Tank cap. Are there any tips for flushing and refilling the header tank and heat exchanger (and there is a calorifier as well of course). Any tips appreciated.
 
It's a while ago but I did have them a Long time, I recall the drain on the block is stand side. Bottom at the rear. You may find you open the cock and nothing drains as it's clogged with crud. I think it unscrews from the block.
 
Thanks. 'stand side' do you mean starboard? I can't see it and I fear it may be port side completely hidden and prevented access on account of the oil cooler. I have absolutely no temperature issues but in a 5 hour journey the header cap will decant about 100ml coolant - not having a recovery type cap means an expansion tank is not feasible - 100ml from 20 litres capacity is hardly significant but it is annoying. A look at the decanted coolant suggests not a crisis but a regular flush would be worthwhile. If I unopened the heat exchanger ends, I would empty all the water over the electrics - 2 alternators, a separate regulator and a starter! Not the best! The lower point is at the calorifier which is hardly the best either - and wouldn't drain the block!

Ah. Just viewed a utube video of a 6.354T and I can see the drain tap, port side aft, low down. Exactly where it is hidden behind the oil coolers. Perhaps I can feel it and access. Unlikely but.....

Thanks ben.
 
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Thanks ben. Found it today - port side down - deeply hidden behind the huge oil cooler (which also has a drain hidden away). Has a rather vulnerable small thin brass handle - and bizarrely the direction of the handle looks like the drain tap is open! Not that anything leaks.
 
tillergirl said:
Thanks ben. Found it today - port side down - deeply hidden behind the huge oil cooler (which also has a drain hidden away). Has a rather vulnerable small thin brass handle - and bizarrely the direction of the handle looks like the drain tap is open! Not that anything leaks.
Click to expand...

I'd forgotten that! Yes, those little brass drain valves on both the block and the Bowman coolers have the handle perpendicular to the flow when open! Fooled me once.

You asked earlier about refilling - never had a problem, 50/50 ethylene glycol and pour it in by the jug load.

If losing 100ml of fluid after a 5hr journey, I would say for an old 6.354 that is virtually nothing and that you might be over filling, they tend to settle with the header tank only about half full.

Fabulous old engines, a real sweet spot at 1800rpm.

Just watch out for the casr iron manifold and charge cooler body.
 
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Phew, that's good news. The Bowman tap was 'in-line' as well!

I am relaxed about the heat exchanger having had some good runs and your comments. The engine hadn't been used much, if anything, in the past 18 months. The original cap showed signs of blow and having replaced the cap I was worried about the coolant loss. But no temperature issues, minimal loss and I conclude the original cap was worn out - the top washer is worn/frayed, hence the blow.

A flush is worthwhile. The engine oil is still clean but I intend to set her up 'fresh' for next season.

Thanks Ben.
 
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