D2-55A coolant drain plug

[MagicalArmchair]

Every other year I replace the coolant in our trusty D2-55A Volvo engine. What winds me up about this process is the drain plug, on the stb side of the engine, that once taken out, then liberally sprays the captain and the stb aft cabin in coolant as it shoots out under pressure (I suppose the pressure isn’t a bad thing, as it’ll pick up any crud with it).

I have seen modifications that drill the center of the drain screw, tap it, and then put something a bit more civilised in, like a bleed screw? Anyone have experience of that modification? Is it a good fix?

 

[Plum]

Every other year I replace the coolant in our trusty D2-55A Volvo engine. What winds me up about this process is the drain plug, on the stb side of the engine, that once taken out, then liberally sprays the captain and the stb aft cabin in coolant as it shoots out under pressure (I suppose the pressure isn’t a bad thing, as it’ll pick up any crud with it).

I have seen modifications that drill the center of the drain screw, tap it, and then put something a bit more civilised in, like a bleed screw? Anyone have experience of that modification? Is it a good fix?

View attachment 202982

On my VP diesel the coolant drain plug is in two parts with the outer part acting as a tap onto which you can fit a drain hose when required,. Mine is this one that fits a whole load of VP engines but which does not list that it fits your engine, or maybe it does.
Drain Tap - Genuine

 

[Ammonite]

Much easier to buy a suitable bush and fit an off the shelf drain cock. I think the block is 3/4" npt and the part referenced above us 1/4" npt, although you'd need to double check. Having said that I've a drain cock fitted to by MD2040 and the bore is very small which makes it frustratingly slow so I just remove it and shove a suitable sized rubber pipe in the hole. Works fine but access is good.

 

[VicS]

Every other year I replace the coolant in our trusty D2-55A Volvo engine. What winds me up about this process is the drain plug, on the stb side of the engine, that once taken out, then liberally sprays the captain and the stb aft cabin in coolant as it shoots out under pressure (I suppose the pressure isn’t a bad thing, as it’ll pick up any crud with it).

I have seen modifications that drill the center of the drain screw, tap it, and then put something a bit more civilised in, like a bleed screw? Anyone have experience of that modification? Is it a good fix?

Why is the coolant under pressure?

Maybe draining most of the coolant via the heat exchanger draincock ( #2 in the attached diagram) can be done in a more controlled manner. Finally removing the plug from the block to drain the remainder

 

[penberth3]

Much easier to buy a suitable bush and fit an off the shelf drain cock. I think the block is 3/4" npt and the part referenced above us 1/4" npt, although you'd need to double check. Having said that I've a drain cock fitted to by MD2040 and the bore is very small which makes it frustratingly slow so I just remove it and shove a suitable sized rubber pipe in the hole. Works fine but access is good.

Is there room to screw in a 90 degree M/F bend?

 

[MagicalArmchair]

Why is the coolant under pressure?

Maybe draining most of the coolant via the heat exchanger draincock ( #2 in the attached diagram) can be done in a more controlled manner. Finally removing the plug from the block to drain the remainder

View attachment 202986

Is that the drain on the raw water side? If it's not, that would be genius, as it's lower down it would also get more coolant out I bet too.

Just the head of water is giving the pressure. I could pop a hose in the hole, however, there would be the usual scramble of plug out, coolant everywhere, and then hose in. Better than what I am currently doing though.

Much easier to buy a suitable bush and fit an off the shelf drain cock. I think the block is 3/4" npt and the part referenced above us 1/4" npt, although you'd need to double check. Having said that I've a drain cock fitted to by MD2040 and the bore is very small which makes it frustratingly slow so I just remove it and shove a suitable sized rubber pipe in the hole. Works fine but access is good.

Good idea just getting a suitable bush if I got that route.

Thank you all for your input.

 

[VicS]

Is that the drain on the raw water side? If it's not, that would be genius, as it's lower down it would also get more coolant out I bet too.

Just the head of water is giving the pressure. I could pop a hose in the hole, however, there would be the usual scramble of plug out, coolant everywhere, and then hose in. Better than what I am currently doing though.



Good idea just getting a suitable bush if I got that route.

Thank you all for your input.

No its the heat exchanger coolant drain.

Read the section in your owners manual on maintenance of the freshwater system
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