[SOLVED] D21 Z24I to KA24e conversion, and other rambling

[datzenmike]

The Z24 and the truck KA used the 240mm clutch and flywheel.

[lovot]

Thank you.

[lovot]

oil pan is a no go, the timing cover has a spot that sticks out further, so even though it will bolt on it won't cover the entire bottom of the engine.

 

Going to need a someone with a lathe to adapt the spline collar from the Z24I dizzy so it will fit on the older style Z24 dizzy, i think there are people in town that can do this as I don't have access to a lathe anymore.

 

There's a rectangular port on the KA24e water pump input, I can't figure out what it's for, it's not for the thermostat, and it's not for the heater core. If it's not important I can block it.

 

List of parts that the "complete engine" did not come with, and the Z24I parts aren't compatible with:

 

Dizzy* (requires adapter plate, will attach to the shaft but it won't seat all the way, adapter plate both shims it and fixes the bolt pattern. old style NAPZ24 dizzy has additional problems, even with an old style oil pump shaft.)

valve cover

oil pan

water pump

water pump/fan pulley

fan clutch

harmonic balancer

intake manifold

thermostat housing

[lovot]

Still wondering what the rectangular port between the main radiator return, and the heather core is for, going to make a plate to cover it, since it's a huge hole in the cooling system, but I still want to know why it's there. You can see the back side of the thermostat through the hole.

 

There's a port that goes into the timing cover just below it, also not sure what might go there, can sort of see the oil pump/dizzy shaft through it. It needs plugging as well.

 

The cooling system changed, the water jacket goes past the hole the dizzy is supposed to fit in now. The hole has 2 "steps" now, each step is positioned so Z24 dizzys will not fit, the collar that allows the standalone dizzy to rotate has to be trimmed back so it goes in all the way, then the bushing housing has to be turned down until it fits past the second step, I couldn't see a good way to get the dizzy into a lathe, so grinder and file work had to do.

 

The motor mount brackets also changed, had to get a set of used ones, but an adapter plate could also do the job.

 

main thing is I'm waiting on a valve cover, USPS may have lost it.

[datzenmike]

6 minutes ago, lovot said:

Still wondering what the rectangular port between the main radiator return, and the heather core is for

 

There's a port that goes into the timing cover just below it, also not sure what might go there,

 

Post pictures...

[lovot]

Those 2 ports

[datzenmike]

 

This is the block vent. It goes into a container to separate oil droplets, like a catch can but drains oil back into block, and fumes go by hose to the PCV valve on the intake.

 

 

 

 

I don't know where that other hose goes to but the heater hose connects to here. It has a flat cover with two bolts and a fitting for the return heater hose.

 

 

So nothing is there for no reason.

 

 

Use the RTV shit sparingly. If it squeezes out where you can see it, it's also squeezing out inside and clogs the rad tubes and heater core and elsewhere...

 

 

I pulled this RTV worm from my KA24E head coolant passage. I never use this shit and cut my own gaskets. GM owners are the worst for this, they have no idea what a gasket does and slather it on like they're icing a cake.

[lovot]

OK, so what is the port in the back for, if the square hole is for the heater, what's the port that's designed to have a hose on it already for?

 

I smear the RTV on there with my fingers, there's already squish out on the outside before the part goes on, some does get on the inside as well, but not big gobs that break off and clog shit up. The gasket that came with the pump was damaged in shipping, so there's no gasket in there, just RTV, the master gasket set that came with the engine was missing the ones for the PCV heater core port thingy, and thermostat housing, so those get RTV as well. I should get some of those hole punches for gasket material so I can make gaskets more easily, but I presently don't have a set.

[lovot]

Where would I attach the PCV? It goes after the air filter, but before the throttle plate, same as the breather on the rocker arm cover, right?

[datzenmike]

The PCV is somewhere on the intake plenum and under vacuum. The valve cover hose goes to the air filter housing.

 

The other hose fitting looks like a big U hose goes to it, so it must go to something nearby.

[lovot]

The only thing on this truck that needs hot water is the heater core, so I'm stumped. The big hole is getting plated over, if it needs to attach to something later I'll mod the plate, heater core gets hooked direct to the existing hose hookup.

 

An oil separator will be easy to fabricate, there should be somewhere to attach the PCV to the intake I have, if not, I'll attach it where the EGR used to be since I tapped it for pipe threads already.

[lovot]

Actually, I think I remember where the PCV valve is now, on trucks it comes in the middle where all 4 holes meet, I thought it was the hookup for the brake booster, but that wouldn't explain the oil residue I remember being there, so the brake booster is going in through the EGR instead.

Edited March 23, 2019 by lovot

[datzenmike]

Water has to exit the engine on the pressure side of the pump and go back on the inlet for there to be flow.

 

YES the center of the throttle body.

[lovot]

The thermostat regulates the flow from the radiator to the pump, the heater core gets constant flow since it's on the other side of the thermostat, that's 2 things that need pump flow. There are 3 holes on the input side (timing cover), one for the heater core, one for the radiator, and a mystery hole that I don't have any sort of reference to figure out what it belongs to, you say the rectangle goes to the heater core, and I believe it, but that then leaves another hose hookup with nothing to attach it to. On the output side (intake manifold) there are 2 holes, one for the heater core, one for the radiator, no mystery hole. One of those inputs is getting plugged, and big rectangle is the most convenient.

[datzenmike]

 

http://www.infamousnissan.com/forum/showthread.php?t=37775

[lovot]

Thank you, but now where does the heater core input go? it looks like hose B goes straight to what I assumed was the heater core input, so now the heater core hot side has nowhere to attach.

 

 

Judging by how close the thermostat plate is to the bypass port, there is significant restriction there, even with the thermostat closed, using a T and an elbow to connect the heater core input to B looks like a potential solution. The coolant outlet slung under the intake manifold is not restricted, so it should be able to feed the bypass and heater core which both have significant restriction on their own, also means I can use straight lines instead of weird U hoses that are special order.

[lovot]

All right, got everything working, pickup is now drivable.

 

Still not sure who made the carb I have, and the seller doesn't have any documentation on it, and i probably won't be able to find parts, because of this I'm tempted to switch to a Weber carb. Not sure which Weber to get since they didn't exactly build carbs specifically for a KA24E. The fuel solenoid and electronic choke both seem to have died on the carb I have, it plugs straight into the wiring harness on the truck, which is hot when the ignition is on. Both worked during the early tests I was doing, but now neither do, the fuel solenoid is always open (even when unplugged), and the electronic choke, which controls the fast idle cam as well is always on. I bent the tab on the vacuum actuator that mostly disables the choke once it has vacuum, so that it fully disengages the fast idle cam and choke as a workaround for the electric choke not working.

 

Ended up using a T and a street L to connect the bypass loop to the hot side of the heater core, seems to work fine, no coolant comes out of the overflow, even after it's been running for a while, and the heater works, so that's solved. The Z24 main radiator hoses hook right up.

 

The PCV seems to be working fine, the oil separator I made seemed to work on early tests, but I'll pull the hose when I do the 50 mile oil change to see if oil is still getting past the separator.

 

Wanos dizzy is working great, probably need to use a timing light to make sure it's exactly in time, but I got it close enough by hand so that it runs properly

 

 

 

Other notes: the Z24i fan will work on a KA24e fan clutch, note that the stock Z24i fan is noticeably smaller, and flows less air, and the Z24i fan clutch is also smaller. The fan shroud for a Z24i equipped truck is compatible with a KA24E fan, there is still clearance between the blade tips and shroud.

 

The alternator adjustment bracket requires modding to work, for me all I had to do is use a vice to straighten out the bend in the Z24 adjustment bracket, and use one of the water pump bolts to affix it to the engine.

[lovot]

But for real, does anyone have any Weber carb recommendations? I already know I'm going to need to fabricate an adapter manifold to get it to fit, so don't worry about that.

[datzenmike]

32/36 would be my choice but a 38/38 for the most power. Redline or Pierce Manifolds should be able to sell you one. If you have the Hardbody intake it would be simple to make an aluminum adapter plate that bolts on where the throttle body was.

 

 

[lovot]

Thank you. Looks like a lot of those kits come with the air filter assembly too, nice.

[lovot]

What's the main difference between the two carbs?

[datzenmike]

The numbers are the diameters of the barrels in millimeters or thousandths of a meter.  ... 32mm primary and 36mm secondary.

 

The 32/36 has a progressive throttle in that the primary opens to about 60%? and then the secondary begins opening. This allows the vehicle to run mainly on the primary for good drive ability and mileage and step into it for power

 

The 38/38 has a synchronous throttle in that both 38mm barrels open together. Has good top engine power but requires you to be more aware of throttle position so you don't open it too suddenly at low speeds. A 2.4 liter engine should be able to handle a 38/38. Mileage probably won't be as good as the 32/36

[lovot]

I mainly need the low end torque anyway, which the 32/36 should work fine for, if I want more out of it than that I'm going to need a turbo. the footprint on a 32/36 looks similar to the carb i already got, if it is, then it will bolt right on to the adapter manifold I already had to build to get it to interface with the KA style intake.

[lovot]

The intake manifold on the KA24E is blocking the oil filter from unscrewing all the way, going to have to take the intake off to change it out. Is there an adapter that bolts on to the oil filter flange that would convert it to a hose manifold so a random spin-on filter manifold could be mounted somewhere more accessible, or am  going to have to build one? That area of the engine is already as busy as a 3 pecker billy goat, I would rather not have the oil filter directly in the middle of that mess.

[datzenmike]

I think there are 4 bolts on the oil filter adapter. Remove and try turning it 90 degrees either way to the sides??? May not work.