What Engines Fit My 720 4wd?

[gone2long]

Hello gang,

I'm new here, and I'm retired, living in the Philippines.

According to my research, the 1979 and 1980, 720 models came standard with an L20B, but my truck has a Z18 in it, which I think was put in by a previous owner.

The engine needs a new timing chain and I can't find one, so I am thinking of swapping in a Bluebird L18 or a Z20. Wondering if these will fit my 4wd transmission?

Also, what about a Z22 or Z24; will these larger engines fit under the hood and onto the transmission?

Other options might be motors found in early model Pathfinders (1986) or so. There are a lot of these still on the road around here with SD23 and SD25 diesels in them. Will these fit?

Any help or advice would be greatly appreciated.

Regards,

G2L

[PEZi]

From what I understand, you're stuck with what you have. I may be wrong, but the Z22 and Z24 would need the transmission out of the model that came with said engine. Like I said, could be wrong, though. As far as the Bluebird L18 or Z20, you're looking at the same situation, but the other problem you'll run into the the oil pan not clearing the steering and suspension members. I'm going to have to look into it a little more to see if the Z22 or Z24 would work. What is your transmission?

[gone2long]

From what I understand, you're stuck with what you have. I may be wrong, but the Z22 and Z24 would need the transmission out of the model that came with said engine. Like I said, could be wrong, though. As far as the Bluebird L18 or Z20, you're looking at the same situation, but the other problem you'll run into the the oil pan not clearing the steering and suspension members. I'm going to have to look into it a little more to see if the Z22 or Z24 would work. What is your transmission?

Hi Pezi,

Thanks for your reply.

Now that you've mentioned it, the transmission is probably going to be the problem, when considering swapping in a Bluebird or other non-truck engine, because my transmission is a fairly heavy duty 4wd model. It has 4 forward gears off the floor, a normal, 2x2 gear ratio, a low 2x2 ratio, a 4x4 setting, and a low, 4x4 gear ratio as well.

Consequently, our best bet seems to be switching in an early model, 4x4 Pathfinder engine, which I assume, would come with a similarly heavy duty transmission. As you note, in this case, the key question then would seem to be whether or not a Z22 or Z24 would fit. Also, what about those diesel SD 23 and 25 engines I mentioned? They are probably the easiest to find out here.

Thanks again for getting back to me,

G2L

[PEZi]

Its interesting you mention that the diesels are easy to find. Here in the states the diesel engines are not only hard to come by, but no one has them and thus info on them is slim. Ergo, I have no idea if one would work as I know nothing about them!

[gone2long]

... On the SD 23 and 25 diesels - Understood. - From what I have found out on the net, these diesels were never sold in the US, but, it would seem that, if such motors were engineered to fit the same trucks designed to take the Z22 and Z24 engines (1983-86 720) then, they should fit any truck that can take a Z22 or Z24. Of course, this is just conjecture. Tell me what you think.

... On the Z22 and Z24, I hope you are still looking into this. Tell me what you find out.

... Also, let me reiterate that my truck, which is probably a 1979 model (see my other threads for more on that) was designed to accomodate an L20B or an Z20 engine. Since it actually has a Z18 engine in it (never stock in the 720) that would suggest a relative degree of interchangability in these engines back in the early 1980s. This is worth taking note of.

... Lastly, getting back to the idea of swapping in an L18, Z18, L20, or Z20 from a Bluebird, Silvia or Skyline, another thought occurred to me. Why would the original vehicle matter? The engines in the swap vehicles would be the same as those used in the early model 720s. However, the donor car and the receiving truck chassis would be different. So, the issue would essentially be ALLIGNING the car engine to the truck transmission, no?

Please pardon my ignorance on this issue because I am not a mechanic, but it seems that, if these various cars and trucks were designed to accomodate the same engines; then, the only mitigating factor in terms of their transferrence from one vehicle to another would be how each "donor" motor would "fit" under the hood (meaning attach to the engine mounts) of the reciving vehicle and how the donor engine would allign to the receiving vehicle's transmission.

In other words, in vehicles which have been designed to accomodate simlar engines, the location of the bolts and holes on the various engines and various types of transmissions should all align. This would seem to be the case, even if the donor engine were in a 2x2 vehicle and the reciving tramsmisson was in a 4x4. The major question then would be as follows: When fitted under a hood and onto a receiving chassis and motor mounts, would the donor engine align with the receiving transmission. Am I right on that?

If the above is true, then, it would seem that an L18, L20 or Z20 car engine should "fit" my 720 truck transmission. However, it might very well not "align" to the transmission once fitted onto the existing engine mounts and chassis.

Again, however, there seems to be a lot of leeway in terms of fitting these various older engines to the various chassis. As noted earlier, I have a truck designed to accomodate a L20B engine, but I've got a perfect fit with a Z18 (which was never stock in any 720, anywhere).

Get back to me on all this, if you can spare the time.

Best regards,

G2L

[PEZi]

The biggest thing I need to look at is whether or not the transmission you have will accommodate the Z22 or Z24. It would help to know your trans code, but I'm sure I can figure out whether or not the engine you have fits into a trans which also allows for a Z22 or Z24. As far as the car engines, they just weren't meant to clear certain things with the suspension and steering. For example, the KA24 in the Hardbody trucks and the 240sx is the same engine... however, the car one cannot be placed in the truck without taking the oil pan off of the truck version and then modifying the oil pickup. You'd run into the same problem with engines out of earlier cars.

[gone2long]

Yeah,

I finally get the point about the oil pan etc. But heck, mechanics, machine shops and welders out here are good at doing such stuff, and they work cheap. They literally manufacture their own vehicles (like mini tractors) using 4 hp pump engines, motorcylce chasis, and a bit of glavanized steel for the body, so a little adaptation will not present a major problem (I don' think).

However, easierst route does seem to be the Z22 or Z24. I don't have the transmission number for my vehicle, and I'm not sure how the heck to find it.

Give me a hint where exactly to look, and I'll let you know what I find out. Obviously, I'm a relative novice at such stuff.

Sincerely appreciate your help,

G2L

[PEZi]

I know its stamped on there somewhere. Not sure where to look exactly, though. I have to go to school so my time is limited, but I will look in to what transmissions the Z18 fits into, and the cross reference off of that to see if I can get you an answer.

[gone2long]

... Let me know what you discover.

G2L