I'm liking those odds, I'm 25+ years. Started my new job last week so haven't had time during the day to work on it, having money to throw in it and access to parts suppliers will be good again

For what ever it's worth, over the last 25+ years the three head gasket failures I've seen or dealt with were a case of coolant in the number 2 cylinder...............the last one on my car was really fun. No symptoms other than water disappearing..........finally I held the revs at 5000 RPM's with the rad cap off, mild bubbling in the rad.

Tom

that's the funny thing I was thinking it was gearbox rattles in 4th, just had to wind down the timing :( I'd rather have that peppyness it had with 13 deg static, not sure what it ends up on at full advance

sounds like a handy tool I should have bought years ago.

A warped head might cause that. There's only two little holes into the head by each cylinder, and two larger holes at the back.
See if you can get your hands on a spark plug compressed air fitting. (Like the kind you'd use to pressurise the cylinder to change Valve guide seals) Then pressurise each cylinder one at a time with the radiator cap off. You'll soon see if a cylinder has a breach to the cooling system.

Sounds like me chasing gear box rattles etc

edited

Well it all started last December when I was competing at a motorkhana. Somehow I managed to loosen the flywheel and limp it home pressing the clutch. The motor came out in February I think and has been apart...until last week.

After getting the last of the bits I felt like buying for now back from my engine builder I decided I'd start slowly putting the Y back together. I had more motivation given that it was my birthday on Tuesday and I wanted to run it on the weekend at my local drag strip as unfortunately it's time has come to close (developers finally crushing the land lease deadlines). I was keen to see if throwing my accumulated parts together might land me a 17 flat or better.

Anyone that has ever been in my shed over the last few years know that getting ANY work done is an effort in itself (it really needs a clean and to sort out Datsun gear some of you might get more use out of) but I pushed ahead and went about the task of reassembling my motor.

Well let me tell you I was running around like a mad chook since I hadn't really planned ahead, sometimes the drive out of town works against me because I say I'll only be this long but end up being 3 hours etc. This was starting to stress me out since I wanted to have the motor in and start putting 500 break-in km on it on Wednesday and service it ready for another 200km worth of driving to heat cycle the oil enough to comfortably thrash it at the drag strip.

With the help of a mate I magage to get the motor in on that cold night blah blah blah

Here's the interesting info.

Got the car running and drove for an hour, pulling up to play with timing. At one point the car was getting to 100 deg when I stopped so I set off again and stopped when it was back in normal temp. This is when I noticed a hissing noise and saw coolant frothing from the timing case behind the water pump. I turned the car off to tighten up the bolts and that's when it got interesting, I couldn't start the car again. There was just no juice to do it. While it was starting to cool down I pulled off the oil car to notice the milkshake we all dread, then I pulled off the radiator cap to see the finns instead of coolant.

It took 1.25 litres of water to fill back up. 2 oil changes (first dump was a nice brown watery concoction about 4-4.5 litres) and run up to temp each time it's still showing signs of water. After talking to Ian about it I started checking into the head gasket theory.

Is it possible for the head gasket to leak coolant into #2? Only seem to find noticable coolant in there, or is the more likely cause my head warping. I plan to test the head gasket tomorrow and pull the head off if tightening it more doesn't help. #4 seems rich too for some reason, could a smashed intake valve seat cause that?