??flywheel??

[cbattey224]

i have an L18 and it was auto. The bolt pattern for the flywheel is 5. I got a motor and trans combo off a buddy. Its an L18 with a manual. I was gona put the trans on my motor. But the flywheel is a 6 bolt pattern? Whys that? Also i got a new clutch and i got one for a L18 but its smaller then the one i have. Is it possible that the flywheel and clutch are off a z or something? But how is an l18 have a 6 bolt pattern?

[72240z]

The big L's l/ld24/26/28 are all 6 bolt so it could def be a clutch/flywheel combo made for one. Whats the size of the clutch?

 

The 6 bolt L18 crank could be a nissan comp crank. They came 6 bolt.

[cbattey224]

yeah... the clutch is about 2 inches bigger then the stock one i got for it. so would that crank be a better crank??

[DanielC]

Yes, you do have a better crank.

There was a lot of JDM engines imported into the USA, for various reasons. For quite a while you could buy a Datsun engine that was used in Japan, that was in a car that was pulled out of service, with only 30 or 40 thousand miles on it. These engines were way cheaper to buy, than the cost to rebuild the engine you had in your Datsun. These engines were typically bigger, had higher compression heads, bigger valves, a slightly more radical camshaft, and a fully counterbalanced crankshaft. There was no way a typical mechanic could rebuild a L-16 motor to the same tolerances the JDM engine had, even with the miles on it. And you would still have a smaller engine, with low performance parts.

So, when your L-16 needed a rebuild, you could, and easily spend over a 1,000 on rebuilding it, or you could buy a JDM L-18, with high performance parts for half of that, and just drop it in.

[cbattey224]

i think its an l20b motor. i thought it was a l18. so now im in the search for a flywheel

[72240z]

If it's a 6 bolt a flywheel is easy to find.

[cbattey224]

no its a 5 its for an L18. thats the problem i have a six

[72240z]

Yes I know, once again it's easy to find a 6 bold l6 flywheel. Read the 2nd post in this thread, then add the 240sx and hardbody pu.

[DanielC]

L-20-B motors have two bolts really close to each other at the top, on both sides of the timing chain cover, right under the cylinder head. It looks like thay just added about 3/4 of an inch to the top of the motor, because it is exactly what they did.

There is also a serial number pad on the right side of the engine block, near the rear. The pad is two parts. Motor type, and then the serial number.

[cbattey224]

the motor going in my car is a 5 bolt pattern. the flywheel i have is a 6 bolt pattern

[datzenmike]

L18??? L20B??? irrelevant! If you have 5 bolt crank, only another 5 bolt will fit it. Clutch size is totally dependent on what the flywheel was designed to take.

 

5 bolt flywheels came in 200mm and 225mm clutch size.

6 bolt flywheels came in 200mm, 225mm and 240mm clutch size.

 

5 bolt flywheels were used on L16 and L18 motors

6 bolt flywheels were used on L20B, L24, L26, L28, Z20, Z22, Z24 motors

 

Any 5 bolt flywheel will fit and interchange with any 5 bolt L motor.

Any 6 bolt flywheel will fit and interchange with any 6 bolt L or Z motor.

 

After all these years any flywheel could have been swapped on but generally:

 

All car L16 and L18s were 200mm.

All truck L16s were 200mm

All car L20B and Z20 were 200mm. Z22 were 225mm

All 620/720 truck L18, L20B, Z22 were 225mm. All Z24 and Z20s were 240mm.

Car L24/26/28 were 225mm and 240mm

[72240z]

Yep good sum up, just to add 240sx uses a 6 bolt 220mm as well and vg harbody uses a 240mm 6 bolt. Not that it matters for this convo lol

[RoadRace]

Yes, you do have a better crank.

There was a lot of JDM engines imported into the USA, for various reasons. For quite a while you could buy a Datsun engine that was used in Japan, that was in a car that was pulled out of service, with only 30 or 40 thousand miles on it. These engines were way cheaper to buy, than the cost to rebuild the engine you had in your Datsun. These engines were typically bigger, had higher compression heads, bigger valves, a slightly more radical camshaft, and a fully counterbalanced crankshaft. There was no way a typical mechanic could rebuild a L-16 motor to the same tolerances the JDM engine had, even with the miles on it. And you would still have a smaller engine, with low performance parts.

So, when your L-16 needed a rebuild, you could, and easily spend over a 1,000 on rebuilding it, or you could buy a JDM L-18, with high performance parts for half of that, and just drop it in.

 

 

it was my impression that ALL L18's (local and JD)had fully counterweighted cranks - can someone confirm this?

[datsunaholic]

Mike, my '83 720 2WD (Z24) is 240mm. I believe that all 720 NAPS-Z ones are 240, and that Z22E 200SXs are 225mm.

[datzenmike]

Right again Doug. The clutch and PP listed for the Z22 is marked 200mm but the numbers cross reference to a 225mm so I'll go with that. All Z24/Z20s were indeed 240mm. Only the diesel had the 225mm.

 

Info corrected with thanks.

 

mike

 

 

I pulled an '80 4X4 flywheel off the L20B motor and it was a 240mm so always thought all 4X4s after were that size. Must have been swapped in as the motor had a U-67 and stove pipe exhaust.

[DanielC]

All L-18 may have a fully counterbalances crank, I do not know. I do know the JDM L-18 I got had one.

Your mileage may vary.