Yanmar 4JH3E Coolant

[Esmerelda]

I know there have been many threads on this subject, but I am at the stage of the more I read, the less I know... Therefore my simplistic question which I am hoping someone can help with is would this coolant http://www.halfords.com/motoring/en.../halfords-oat-antifreeze-concentrate-5-litres be suitable for a Yanmar 4JH3E. It is a long life silicate free OAT coolant

Thanks

 

[RichardS]

I know there have been many threads on this subject, but I am at the stage of the more I read, the less I know... Therefore my simplistic question which I am hoping someone can help with is would this coolant http://www.halfords.com/motoring/en.../halfords-oat-antifreeze-concentrate-5-litres be suitable for a Yanmar 4JH3E. It is a long life silicate free OAT coolant

Thanks

The genuine Yanmar coolant recommended for this engine is a longlife coolant: http://www.ebay.co.uk/itm/Genuine-Y...nt-Ultralife-YG30R-Gallon-50-50-/222091028829 and therefore the Halfords version, or any other OAT coolant, will be fine.

Richard

 

[dom]

I know there have been many threads on this subject, but I am at the stage of the more I read, the less I know... Therefore my simplistic question which I am hoping someone can help with is would this coolant http://www.halfords.com/motoring/en.../halfords-oat-antifreeze-concentrate-5-litres be suitable for a Yanmar 4JH3E. It is a long life silicate free OAT coolant

Thanks

It will be fine, but if there is something different in there now be careful to properly flush the system through a couple of times first (which must include a thermostat open phase) to get as much as possible of the old stuff out.

 

[Esmerelda]

Thanks both for your advice

 

[Mark Payne]

It will be fine, but if there is something different in there now be careful to properly flush the system through a couple of times first (which must include a thermostat open phase) to get as much as possible of the old stuff out.

Ok so I have just done this job on my 4JH4E. I used the OAT coolant from Halfords. The old stuff (unknown origin) was definitely different, it smelt of glycol.

I bought two 5L deionised water bottles and effectively flushed the system twice before adding the new stuff.

Start by getting the engine up to temperature so that the stat opens. You will need to find both drain points. On the 4JH4E the easy one for me was on the port side as I access from this side. The Stb one took me ages to find!

Once at temp. I dumped the old into my engine bilge and then I hand pump it out into containers. Then I flush the deionised water.. put it in.. run up to temp again.. dump. Repeat. Finalise with the new stuff .. also added to the expansion tank as well.

Ball ache of a job but there ya go!

M

 

[VicS]

Ok so I have just done this job on my 4JH4E. I used the OAT coolant from Halfords. The old stuff (unknown origin) was definitely different, it smelt of glycol.

I bought two 5L deionised water bottles and effectively flushed the system twice before adding the new stuff.

Start by getting the engine up to temperature so that the stat opens. You will need to find both drain points. On the 4JH4E the easy one for me was on the port side as I access from this side. The Stb one took me ages to find!

Once at temp. I dumped the old into my engine bilge and then I hand pump it out into containers. Then I flush the deionised water.. put it in.. run up to temp again.. dump. Repeat. Finalise with the new stuff .. also added to the expansion tank as well.

Ball ache of a job but there ya go!

M

Low silicate antifreeze and OAT antifreeze are both ethylene glycol based. It is the corrosion inhibitors which are different. Ethylene glycol is odourless!

The recommended procedure if changing from the old low silicate type of antifreeze to OAT includes a flush with an oxalic acid solution although some types are claimed to be compatible with any other antifreeze. Presumably this is to remove silicates absorbed onto the surfaces within the cooling system.

It may have been a ball ache job but it would have cost an arm and a leg to have been done by a marine engineer easp if done properly with the oxalic acid flush.

 

[dom]

Start by getting the engine up to temperature so that the stat opens. You will need to find both drain points. On the 4JH4E the easy one for me was on the port side as I access from this side. The Stb one took me ages to find!

Once at temp. I dumped the old into my engine bilge and then I hand pump it out into containers. Then I flush the deionised water.. put it in.. run up to temp again.. dump. Repeat. Finalise with the new stuff .. also added to the expansion tank as well.

Ball ache of a job but there ya go!

M

Yup, PITA job alright. One thing I find quite useful is a couple of lengths of 10mm flexible silicone hose -- available from Amazon for tuppence halfpenny -- which one can stick on to the drain points & then straight into a bucket. Also if a lowish hose on the calorifier comes off one can often get loads of old coolant out from there.

Still, when the sun crosses the yard arm today you have earnt a beer or two