The AUSubaru.com.au Forums

First off , DQ = Dumb Question so no waste much time giving answer !

Just had a chance to look under my L turbo (not you Thomas ! ) and looking at the sump guard, it has no visible securing bolts at the front.

Are they bolted in at the front and involve radiator removal or are they fastener free at the front ?

They fix to the radiator support panel with M8 bolts.

MUDRAT wrote:They fix to the radiator support panel with M8 bolts.

this could easy create some debateor make 1 of us look dumb (prob me) however i thought that the bolts in the bottom of my sump/bash plate were 12mm bolt - oh hold on just reread, whats an M8?

8mm thread. I think the head on them could be 12mm though?

So maybe we're both right

Next time I see you Jaffa I'll give you a quick fasteners lesson :P.

Ah. This is one of those jobs I was talking about where only 1/4 inch drive sockets work.

Yeah 12mm bolt head usually have M8 (metric 8mm stock before threaded ?) with 1.25 mm pitch. Someone talking M8 has probably lost bolt and knows what thread to look for or has repaired thread. Time for some bright lights on the subject.

Thanks

Well the first thing with fasteners is they are named by their thread and pitch - in the basic form head size is irrelevant. You'll find most M8 bolts that you buy in stores have a 13mm head, whereas the ones on your Subaru all have 12mm heads...
A thread is named first by its diameter then by its pitch. This is true for metric and imperial. For instance:
5/16 UNC - 5/16's of an inch in diameter, Unified National Course pitch(18 threads per inch)
5/16 UNF - 5/16's of an inch in diameter, Unified National Fine pitch(24 threads per inch)

Metric is much simpler;
M8-1.25 - 8mm diameter, 1.25mm pitch (standard)
M12-1.75 - 12mm diameter, 1.75mm pitch (standard)
M12-1.5 - 12mm diameter, 1.5mm pitch (fine)

The other main features of a fastener are its length (duh :P) and it's head configuration, whether its a single or double hex, dome head socket cap, etc etc. Most if not all of the bolts you'll encounter on a Subaru are single hex.

Sorry if I'm being a little technical, I did try to make it sound simple but the reread sent me cross-eyed

So Tim does this mean that i now will not be gettting a personal session with you lol

Yeah, I was gonna mention that every new M8 bolt has 13mm head, so such a good reason to stock pile all metric bolts outta cars.

And thanks for being so kind n ot telling me just how dumb a qwestion this was. I was lying under car with head near crossmember - no wonder I did not find the front bolts as they are visible from the front and under bumper bar.

many apologies to all

Just be careful when doing the front sump guard bolts up as they are real easy to snap the captured nut off

Jaffa wrote:So Tim does this mean that i now will not be gettting a personal session with you lol

LOL. I can explain it again some time, much easier in person than on the net.

Jono, no need to apologise, its not a dumb question really. It's something I used to encounter every day at my old job, people would ask me for a 12mm bolt that's 25mm long, and just about faint when I brought back an M12 bolt (19mm head!).

I did not say that I did not understand - shit with 2 years of Mech Eng behind me I would want to.

I was just upset by the prospect of loosing some quality 1-on-1 Timmy time