ZD30 - Four Cracked Pistons - Follow Up #62790

At least I now have a thread started that I can post to.

Pistons: 1 and 4 cracked; 2 holed; and 3 OK.

Dealer removed head and reported "Four cracked Pistons" - around $450
"In Chassis - Engine Rebuild Kit" $1100
New Glow Plug - $37 (Nissan Dealer wanted $90 plus). Not sure how the tip became broken on old one - dealer removed head :-) Add all the other 'incidental' stuff - oil, filters, etc say $200

I removed the engine from the car and placed it on an engine stand. I didn't know that you could buy an "in chassis" kit. If I was doing it again on an engine under 100K, this is how I would do it .....

Drain coolant and oil.
Remove head and sump. (may have to lift engine from mounts).
Undo four bearing caps and push conrods up so pistons come out top of block.
Seperate old pistons from conrods and discard.
Fit new rings to new pistons with new gudgeon pins. (Be careful with rings - there is a top and a bottom side and MUST be fitted to the piston grooves as such).
Fit bearing slippers to conrod and cap.
For each piston .... Ensure crankshaft is at bottom of stroke, using ring compressor, fit each piston to cylinder and push down until it sits on crankshaft. Fit bearing cap and snug nuts.
When all pistons are fitted. Torque the bearing nuts. The kit tells you the settings.
Refit the sump.
When refitting the head make sure you have an 'O' ring AND THE GASKET between the front of the head and the back of the timing gear housing. (Some of you will remember that I posted that I HAD FORGOTTEN THE GASKET and had to remove the head a second time) :-(
That's about it. Beats having to crack the transmission and remove the whole engine.

I better post this before I lose it too !!

More to follow ....

Malcolm

Malcolm.
The reason the pistons cracked was most likely over boosting due to a dirty air flow unit, I hope you cleaned that before you started the motor. otherwise well done. Eric.

I finished up using the Nulon 15W-40 Oil.

In preparation for the NEW gauges I fitted a 'T' piece just under the turbo and screwed the oil sensor into the side facing down. I fitted a plug to the other whilst I wait for TJM to get me the oil pressure sender unit and gauges. (I have a slight oil leak at present). There is no way I can get a spanner on to the sender unit under the turbo so I'm thinking of getting a flexible oil line to screw in there and put the sender unit into the end of it. Then I'll have to 'fasten' it somehow. Any other suggestions.

I've now purchased a VDO EGT and boost gauge (0-30 psi), Oil Pressure (0-5 x100 kPa). Yeah I know! They said "that's how it comes 0-5".

I also have a couple of 12V VDO gauges which I'll use for the two batteries.

Wanted a three gauge Pillar Pod (like Chaz has) but TJM says they are no longer made and got a two gauge pod. There was no way I could fit the boost gauge into it without cutting the pod at the back of the gauge. No way. That would be ugly fix. TJM then found out from the pod manufacturer that they are only for 'electrical' gauges. Told them to keep the pillar pod. Now I have to work out where/how I am going to fit FIVE 52mm gauges. Any suggestions.

If you have any specific questions on my rebuild, fire away.

Malcolm

Malcolm, good to see your vehicle going again. Im guessing you are going to sell it before it expires big time in the future?? Michael