One tricky part of the timing is that the crank has 'two' top dead
centers or two different times the mark on the crank can be lined up
right.

You can tell pretty close by putting your finger into the spark plug
hole for number one piston and hand turning the engine with a wrench on
the crank bolt. If the valve timing is right, then as it comes up to
the timing mark you can feel the compression under your finger with it
maxing at the mark then dropping down and sucking on your finger.

Mike

Dave Skirrow wrote:
>
> I did check the timing and I'm pretty sure its right, the marks on the
> belt are lined up in the right place at least. Although I will look at
> it in a little more detail when I try again tomorrow.
>
> Could a blown gasket cause this backfiring through the throttle body in
> any way?
>
> Oh, forgot to say, there was also oil on the spark plug threads when I
> removed them after trying to start it.
>
> Cheers,
> Dave
>
> Mike Romain wrote:
> > If you aren't getting the timing correct you can have the symptoms you
> > are describing. If the valves aren't closing at the right times you
> > will have little or no compression and it will backfire out the throttle
> > body.
> >
> > The oil drip can happen when you are removing the head and doesn't
> > always mean a blown gasket.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's