D40 Navara 2008 Thai timing chain question

[Wadao]

Hi all,

I read on yd25.com.au that “The original yd25 engine had a double row fuel pump chain. The euro 3 and euro 4 yd25 engine use a single row fuel pump chain however the engine still kept double row thickness sprockets and guides”, does this mean that my Thai 2008 RX D40 engine has the original double row timing chain and I’m less likely to need a duplex timing chain upgrade? (Disclaimer: I’ve not yet opened the timing chain cover to inspect the condition of the system yet, but I’m just wonering if I’m likely to need to buy the duplex timing chain upgrade or not).

Thanks in advance!
Wade

 

[BarneyB]

As far as I know, all D40's have a simplex lower chain (fuel pump, vac pump, balancer etc) .....and duplex upper chain.

I think the "original" YD25 they refer to might have been from a vehicle that pre-dates D22's & D40's...?

I have a 2008 Spain build D40 & can confirm 100% the lower chain is simplex (for now )

 

[Wadao]

Cheers Barney,
I landed up buying a second hand engine instead of pulling apart the old one (which I may still do) and it turns out the newer engine has both upper and lower duplex chains - on the 2010 MNT automatic engine …. Not sure if it’s stock or if the owner before me did it but I think it may be stock.

I’ve just today managed to reconnect the newer engine to the gear box and get it mounted, now it’s time to plug and bolt everything back on that needed to get out of the way to remove the dead one.

First time ever doing anything like this but I’m enjoying the learning!!

I

 

[Wadao]

Old one getting lifted out and sitting next to the newer one

 

[Scott52]

I have a 2011 MNT and the original stock lower chain was simplex. I've since upgraded to the duplex kit from YD25. Yours must have been upgraded before.