L28 Engine Reconditioning.

[Kanzen]

Hey Z-fanatics,

After years of torment, I've finally managed to start putting money into my beloved 1971 240z.

The car itself has been sitting for around a year, and the engine has not been turned over for a similar period of time.

Engine block is F54.

Engine heads are P90.

Engine is running twin roundtop SU Carbies.

 

The carbs are bonedry, so those themselves would need to be cleaned/rebalanced.

Getting new radiator, piping, electric ignition and other goodies.

Looking to eventually TURBBBBBBBO the engine, but at this point in time, just looking to have it running on the road.

 

In fear of the engine being seized, that Im curious to see what the condition of the chambers are, Im looking ot get the engine reconditioned.

 

The question being - what does this consist of? what gets checked/replaced? whats required to turn the motor from running leaded fuel to unleaded, can this be done with that procedure?

Before I take it to a professional/ask them, I figured I would try and get a heads up first to see what sort of money I'd be looking at, and ask the REAL professionals.

I live in Australia, and the money is there, I just don't want to go getting ripped off.

Regards,

Leon.

[Xnke]

You don't need to do the leaded/unleaded conversion. You have a P90 head, it already has steel seats.

 

You don't need to do anything to the engine, as long as it ran fine when you left it.

 

Drain the oil, change the filter, change the oil. Pull the spark plugs, and put about a teaspoon of oil in each cylinder, let sit 20 minutes, then put the car in first gear, and rock it a bit if the engine is stuck. If engine moves freely, put in neutral and give the starter a chance to spin it up with no plugs, listen for bad noises.

 

Do a compression check, run down to the local autoparts place and see if you can rent/borrow/buy a compression tester. For a P90/F54 block, assuming the P90 came factory assembled to the F54 block, You already have a turbo engine, and thus should see 120-160PSI compression, roughly. You're not looking for an absolute number so much as that the cylinders are within 10% of each other.

 

Put in new plugs, fill the float bowls of the carbs with fresh gas, and crank'er over. A year is not too bad to leave one of these engine sitting, as long as the throttle plates were closed and the exhaust was on the car.

 

No need to get the engine rebuilt if all that was wrong was that it was simply setting for a year.

 

If you can't get it to fire over, check for spark, then check to see if your timing is correct. The SU's usually don't have too many problems unless they are just worn out.

[sileightygx]

listen for bad noises.

 

i love that part!

 

you can also put the car in neutral and use a socket wrench to turn the crank and see if it turns over freely with the plugs out.

[Kanzen]

<insert awesome rundown here>

 

 

Hey bro,

Thanks for the rundown, definately shines a light on the situation.

I namely wanted to pull it apart to see what sort of condition the cylinders are in, and if anything had been replaced IE : different heads, cam, whatever.

If they werent looking too great, then I was going to just throw a 6.3 in her.

 

Throttle plates were closed, exhaust is on the engine, other then that, hasnt been touched.

Just waiting to get a radiator and new sparkes then Ill follow your advice.

If I run into any dramas, Ill holla back and chances are something'll go wrong hahaha.

Peace,

 

Leon.