Im sick of this sh*t, everythings running fine then something breaks or doesnt work. Now it is the whole bloody motor

I drove my car to the exhaust shop today (strait out of the xtractors) and got my exhaust welded up, lovley. Driving home loottts of play in the rear end and its swaying all over the highway, pull over and only one nut is on the rear left hand side wheel, f**k. Fix it drive home, car acting fine but not idleing the whole morning, just rev's die and then engine cuts out (thought vaccuum leak as new manifold & not blocked off holes properally).
Park it at home and decide to give it a bit of a tune and see whats going on. Try to start it CLUNK CLUNK CLUNK, wat the....

First thing that popped into my head is 'oh sh!t i have a seized piston' soo i try to crank it by hand and it wont budge past TDC of no. 2 & 3. So i look down the spark plug holes & low and behold a see a hairline crack on the top of no.2 piston. HOW DID THIS HAPPEN.......
But all around it it looks like rust but theres never been water in the bores.

It cant be oil starvation i think as it has been working fine up until now & the oil pump runs off the cam so it will get everywhere yeah? The oil pressure solinoid wouldnt make a difference if its stuffed would it?

I will pull the head this sarvo & see if any more diagnosis

I am so pissed off right now, so much money + time has been poured into this car & this is the thanks i get

Dave

Sorry to hear Dave. Keep going with it mate you know the Datto's are worth it in the end. I still hope to see you at the meeting.

Hope it all works out ok.

amen to that dave

im feeling that now, as im doing a block swap, everytime i turn my attention to making it look nice, the mechanics tie up my resources once again

Keep Cruzin man we all have low times but we keep going & going! Bruns

I would suspect that the zhorst shop may have had the left rear wheel off to build your zhorst.
If so that is f*cking piss poor on their part.

Good luck mate, and don't lose heart.

Any clues on what happened to your motor,hope its not to serious.GREG

Ok update on what happened...

I pulled the head last nite and found a nice dirty crack along the crown & dish of no. 2 piston and a large chunk taken out of the dish (about 2mm by 2mm)
Also there is little chips take out of no. 4 piston about 10 of them, this is the same on the head. Little chips on no.4 swirl & a large indentation or 'bluge' in the swirl of no. 2.

I have no idea how this could have appened!!but my guess is something got inside my engine when i had the air cleaner off to adjust my choke.
On that note, i did weld up 2 holes on the back of the manifold with an arc welder - not a great job & didnt completeley fix up the vaccum but ill get it done with a TIG tommrow. Could some of the slag or splatter have broken off (or some that was lying in the manifold) caused my engine to do this?

I will post some pics of the carnage tonite.

Soooooooo how much will a new set of pistons cost & i hope the head is salvagable by surfacing the head.... otherwise more money needed for a A15 head.

God dammit
Dave

I'm guessing that you did the welding repairs while the manifold was still on the engine. Not such a good idea.

The 'quick, easy & cheap' method isn't always the way to go as you are finding out.
Is it possible that a small child could have put a couple of nuts or washers down the carb when the air filter was off?
This happened to a friend & his Big Block Dodge engine many many years ago.

Some pics of the carnage










I need answers please, if i dont get this car moving in the next 3 weeks my parents are going to get rid of it. Their sick of it sitting in the garage not 'doing' anything, and frankly - so am I. They have no Datsun faith and im sorry at the moment neither do I, or it could just be my lack of skills at a mechanic!

What im really looking for is some answers into how and why this could happen so quickly. It ran fine(ish) on the way home. Parked it started it, rev'd it to about 4500RPM then try to let it idle - it did not as it hadnt been doing it all morning then tried to start it again and the piston seized and couldnt crank it by hand either. Suggestions?

There looks to be a bit of detonation on the pistons surface, what causes this? Is it bad mixtures and gas pulsing?

Help
Dave

No the manifold was off the car, in my garage completley away from the car.

Im not sure about a washer, my cat was roaming around in the engine bay so that could be the culprit!!!