Offroad-Express

Sounds like a exhaust gasket, just a single pfffft and the nut is missing from the number 1 flange, sooo hopeing it's not a blown head gasket , these motors arn't known for that are they

Is there anything tricky about changing one out? Looks real straight forward. Will do a compression test first to be sure it's not a head gasket. Check at glow plug holes?

Cheers, Paul

Sounds more like just an exhaust leak. If a nut has gone it'll be leaking past there.
Whip the manifolds off an replace the gasket.
You'll probably find you'll break some studs as they are prone to it so be prepared. You may need to drill out those that break. Either replace studs and nuts or just use bolts. You only need a couple of studs to act as locators.

Or just try and replace the nut. Try the easiest option first.

Head gasket, not exhaust gasket, I guess I knew it was but was trying to make it go away .
Saturday,pull head off of parts truck, pick up gasket set(ordered), pull bad head reinstall good head and hope I can get the system bled, never done it before, Anyone out there want to help, bbq 'n piss offered

Use a genuine head gasket they 20 nicker dearer bt worth it trust me

Found that the gasket seemed to just disinigrate, never seen that happen before, top and bottom of gasket just stuck witth the mating surface and center was soggy

Also found a cracked roller for the rocker arm, bearings in the cylinder(minor pitting) part of the rocker wedged under the cam lobe, swaped out cam and rocker shaft from parts truck. Fought cam belt for about 2 hours, finally got it rotated 360 deg and marks still good . Finish Monday eve.