How to Convert a Maxima Engine to a Z Engine

OK. You're engine's in multiple pieces, for whatever reason. Now, you've got to replace it. Don't despair. It's really not that difficult. Maybe expensive, but not real hard to do.

Engines in good shape, and low miles(~35K) can be found for under $1,000. I found mine w/ 30K on it for $850. Total cost for the job was over $1,000 though. There are quite a few "other" things you'll need to buy. Some have to be bought, others are wear items I decided to take care of while the engine was out of the car.

For background, I'm not an expert mechanic. I'm a college student who always had to fix what he broke. I also did this job while working 8 hours a day(9-5). This includes weekends, so I never was home when I had help. Much of the work was done alone by me; most of my help came only when physically putting the engine in the car. It was also done in mid May, in the middle of a Texas heat wave. I don't think the temp ever got below 95. The work was mostly done outside, as my garage is poorly lit. Believe it or not, it only took about 5 or 6 days to do the job.

Here's an approximate price list::

engine$850.00
timing belt$32.00
water pump~$75.00
various gaskets~$125.00
engine hoist(5 days of rental) $150.00
tools$50.00(already had an extensive collection)
hose(fuel, vacuum)$25.00
other~$125.00
band aids$10.00
replacing dirty shirts$25.00
soap to get clean again$1000(OK, maybe a $1.50 is more accurate)
TOTAL$1400+/- $200

QUOTE GIVEN TO HAVE JOB DONE $2500-3500(over half the price of what I paid for the car-$4500)

In finding an engine, you don't have to get an engine out of a Z. There are quite a few Nissans that use the VG-30 engine. These include the pre-24 Valve Maximas(89?). The V-6 200SX. Possibly the V-6 trucks(Pathfinders). But, when looking for an engine, ask for it by its numerical designation, not by car type. For some reason, 300ZX is synonomous with expensive. Ask for a VG-30 engine, and you might save some money. Luckily, the owner of the shop I purchased mine from was a Z enthusiast(He owns a 400HP+ Twin Turbo Z), though he specialized in European cars. He gave me a very fair price.

In my case, I wound up with an 87 or 88 Maxima engine. It had the compression test tags still on it. Never buy an engine that hasn't been compression tested. And always check the compression after you install it. Who says they didn't forge the tags.

Here's the steps to transplanting a Maxima engine into a 300ZX.

First, you've got to take your old engine out.

  1. If you've got a manual, follow it. Be sure to label all hoses, wires, and connectors. This should take less than a day, if you have help. In this process, I did have one other person's help. Most of the time will be spent taking out engine peripherals(altenator, a/c, etc) and labeling.
  2. When you get the engine out, you might as well take off the oil pan first. Keep track of where you put the oil pan. You'll need it later.

You've got two engines now, what do you do with them???
  1. Get two boxes to put parts into. One for the old, and one for the new. You are going to completely strip both engines. This way, you can keep track of parts. It is probably better to have a better organization than this, but two seperate boxes is a minimum.
  2. I found that the best way to work was to have the old engine sitting on the aforementioned cradle, while the new engine on an engine stand. These are relatively cheap, and will help immensely. Put them side by side.

What to Take Off

Maxima engine first
Order doesn't particularly matter....
  1. Intake manifold. Don't throw it away. You can get money for it.
  2. Valve covers. Keep these also. They are red, and look a lot better than the aluminum covers that are on the Z.
  3. All of the pulley, brackets, and oil pan. Inspect the oil pan for suspicious damage(metal shavings), you might not want this engine.
  4. Dip stick. You'll have to change the location later.
  5. Manifolds.
  6. All of the cooling plumbing.
  7. The oil feed tube in the drain pan. Won't fit into the Z's pan.
  8. I'm sure there is a lot more. When you're finished, the engine should be nothing buy the block and heads. Be sure to remove the sensors and from the Maxima engine also. Many are not compatible with the Z's instruments and electronics.
Time to do the Z's engine.
  1. In principle, you will do basically the same thing you did to the Maxima engine. When you're done, the engine should be nothing but the block and heads.
  2. Don't forget the oil feed tube. This will need to be on the Maxima engine.
  3. Keep track of all the parts!!!! You do not want to lose anything. This includes bolts, screws, clamps, whatever. You will need everything!!!!!

Time to Make a New Engine

  1. Might as well replace the water pump and timing belt while the engine is out of the car. This makes an all day job about a three hour job(maximum). Most of the time comes from time it takes to get it tensioned just right.
  2. Put the Z's oil feed tube into the new engine. This takes about 5 minutes.
  3. You need to put the Z's dip stick into the new engine, but at the back of the engine. The Max's engine has the dipstick towards the front, the Z's is at the back.(On driver's side in both cases)
    1. There are two holes for the dipstick. The one not being used has a plug in it.
    2. Take a hammer and punch and knock the plug out.
    3. Put the dipstick into the rear hole, secure it with some sort of suitable sealant(forget what I used, doesn't leak though).
    4. Put the plug into the empty hole. Remember to seal this too.
  4. Put the Z's intake manifold on. Remember to remove the old gasket(have fun) and put new one on. Nissan sells these relatively cheap.
  5. Put the intake collector on. Remember the gaskets(more fun). Also, you may want to use lock-tite on the bolts. You will find that Nissan did in assembling the engine. Be sure to follow correct torquing procedures as specified by the manual.
  6. Cooling plumbing. This may be easier to do before the intake is put back on. It's up to you to decide.
  7. Exhaust manifold. Gaskets here too. Don't do them and they'll leak. Look for common cracks found in the manifolds. If so, try to find suitable replacements.
  8. Oil pan. Put on once w/o sealing. This way, you can check that the dip stick is aligned correctly. If it is too far off, the dip stick will get hung inside the engine, and you'll never be able to check you oil. Common sense when you see it. After you are sure the dip stick tube is right, put gasket on, seal, and torque.
  9. Valve covers. You can use the Maxx's red ones, just be sure to swap sides around. The Maxx's oil filler is on the opposite side of the Z's. Screw this up, and you'll never be able to put oil in the engine.
  10. You should have a total engine now. If I've left something out, then it'll be obvious. The engine should be complete and ready to put in. This includes everything(all major parts, sensors, etc).

Put the engine in!

  1. Follow what the manual tells you to do.
  2. Of course, it'll run horribly at first. It always takes some tuning. In my case, once it was timed, it still ran terribly. Turns out I had a loose connection in either the ignition or I had a loose connection it the FI electronics.

TIPS

  1. Keep track of where everything is.
  2. Replace wear items. They are much easier to do with the engine on an engine stand.
  3. Clutch job is easy now. Definitely replace the throw-out bearing. Foolish not to.
  4. Assume you are going to lose/break things. Be ready to buy new hoses, clamps, and plastic connectors(for vacuum hoses in particular).
  5. Strip everything off the trash engine. Somebody somewhere wants something you've got.
  6. Use air tools. Saves a lot of busted knuckles and time.
  7. Buy Craftsman. During this job, I've broken more tools than I have in my entire life. Craftsman are warrantied forever.
  8. Clean the new engine. This way, if there are any leaks, you'll see it very early(mine hasn't leaked a drop, though).
  9. Assume the engine won't want to go back into the car. Took quite a bit of man handling of mine.
  10. Have someone else clean out oil pan if you lost piston(s). Too depressing to do it yourself.
  11. If you are cleaning debris from oil pan, use rubber gloves. Else, you'll be pulling metal slivers out of your hand for a month.

REPLACE EVERYTHING YOU CAN EVER IMAGINE BREAKING!!



© z31.com 1994-2010. All rights reserved.