notes on 306 td head to xantia td head swap

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notes on 306 td head to xantia td head swap

Post by ukmobileman » 11 Aug 2002, 03:20

if anybody else is considering putting a pug 306 td head on a xantia td , i will point out that you have to close off the oil feed on the back of the pug head (just under the end of the camshaft) . The xantia head it uses a set screw (allen head) to block of the oil gallery at either end ( front and back ). The pug 306 td uses steel balls sweated/pressed into head (at the front anyway) at the back you must tap a thread into the oil gallery. If you are lucky enough you could use the xantia set screws again , - I found that the heads became chewed upon removal so replace with new. the everso helpful haynes manual qoutes ' the plugs are usually very tight - they may have to be drilled out ,and the holes re-tapped. use new plugs when reassembling ' !!!
As you can't open the other end of the pug 306 oil gallery (steel ball) like you can on the xantia to flush it out you must use some kind of flushing fluid/solvent to clean the oil gallery out - once you have tapped it( i did the tapping upside down!! with the head carefully and firmly help in a vice -held by 2 old head bolts and a block of wood)), compressed air may work but i found that the swaff stuck in the hole because of the cutting fluid i used on tap.
THEN FLUSH IT AGAIN and dry with compressed air (use the oil feed on the head face i inserted a rubber tube into it to allow the solvent into the gallery )
insert new allen bolt into the newly tapped clean oil gallery WITH A LIBERAL coating of thread lock and torque it up (use your common sense here it's an aluminum head). if anybody has the correct setting i would like it please ( i torqued it up to a setting for a simular bolt that screwed into aluminum)which was 33lb/ft or 45 Nm use at own risk
hope this helps
someone did warn me about this problem (sorry can't remember who )i should have checked more carefully!!
Also Gareth (think thats your name) did that 405 head go straight on your zx td or did you have to swap bits about? ( i have my mates zx td that i am involved in helping him repair )
ok thanks all

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Post by gjb02 » 11 Aug 2002, 16:51

Having read that, it makes me glad I didn't get that head after all!!<img src=icon_smile.gif border=0 align=middle>. The only differences with the 405 head were; The intercooler support brackets, one of them was in the center it had to be moved out to the vaccum pump end of the head. And behind the intercooler bracket at the other end there was a blanking plate on the coolant gallery, but on the ZX the blanking plate had an outlet for a small coolant pipe to be fitted to. Yep I missed that one! I found it before I started her up, but with its location behind the Diesel pump it made it quite difficult to change over. Did it eventually though, I had to use a ball ended allen key to get in to the lower bolt. As there was no room for anything else. Its starts after a turn or two of the engine now, hot or cold. So I'm chuffed to bits. I just need to figure out, how I'm going to eat for the rest of the month.<img src=icon_smile_wink.gif border=0 align=middle>
Edited by - gjb02 on 11 Aug 2002 11:53:33