PDA

View Full Version : Engine replacement (vg33)


DamnHippie
01-24-2007, 07:25 PM
Okay, so I've got this engine with an extra hole in it in my Frontier, and I've got an engine in my garage that has just the right number of holes in it. My Frontier is a 99 KC auto trans, the replacement engine is out of a 99 QX4. Other than the different logo on the intake manifold, it appears identical. This is gonna drop right in without a lot of hassle, right?

I got the replacement mounted on an engine stand. I have no idea how many miles it has on it. If I carfax'd the vin would that get me the mileage at the time the qx4 was junked?

I did a leakdown test on it last week and the results seemed pretty good. After putting some oil in the cylinders (engine was cold of course) there was barely any leakage and it was only past the rings, nothing from the valves or head gasket or anything. The needle on the leakdown gauge was right on the border between yellow and green, which seems pretty good for a cold engine.

While it's on the stand I think I'll replace the timing belt. Should I do the water pump too? I've never kept a nissan over 100kmiles before replacing it, so I have no idea how rugged some of this stuff is.

In general I'm starting to mentally ramp up for doing this job soon. Any advice or tips would be appreciated, especially including thoughts on stuff I'm gonna need to buy from Nissan to get the job done (gaskets and that sort of thing). The replacement engine is remarkably complete for a junkyard engine, everything is there except the AC, power steering, and alternator.

DamnHippie
01-24-2007, 07:27 PM
Oh yeah, the replacement engine has exhaust manifolds on it down to the first flanged connector, is there any chance those are the same as the ones on my Frontier? If so, that would rock, because another place (besides the crankcase) that my engine has some extra holes is the passenger side exhaust manifold.

tmorgan4
01-24-2007, 07:45 PM
The exhaust manifolds are different. :(

I couldn't tell you whether the shape of them is any different (I've been wondering that exact thing) but the cat setup is different. The Pathfinders have a 6 bolt circular cat flange while the Xterras and Frontiers have that 3 bolt triangular one.

Tyler...we need to drop this old engine off at Hanks!!!

ChefTyler
01-24-2007, 07:56 PM
Yes we do.
Ian, mind if I pop by with my Chevy after the swap is all done so I can take the motor to Hanksville Hotrods? :D

Lemme go find the 33 swap thread on XOC for ya too, good info

Ditchfinder
01-24-2007, 07:59 PM
when doing your leak down the important thing is that all the cylinders are about the same variance. this translates to lets say cylinder one had about 10% leakdown you want number two within 15% of that number doing the leak down with the engine cold does effect the results a little and of course making sure each cylinder is exactly at TDC. If you have the vehicle VIN you may be able to call your nissan dealer and do A VIN inquiry the VIN cancelation of the car being wrecked with the milleage should show up. If it was updated., at least thats how it works at Honda where I work. Carfax will work with the VIN from the vehicle not the engine number. Good luck nice to see another member. James:wave:

ChefTyler
01-24-2007, 08:06 PM
Found it!
XOC VG33 swap (http://www.xterraownersclub.com/ubb/ultimatebb.php?ubb=get_topic;f=24;t=001493#000000)

tmorgan4
01-24-2007, 09:03 PM
I talked to that guy not too long ago. He seems like a nice guy if you have any questions I'm sure he'd be happy to help.

nissandoms47
02-08-2007, 12:56 AM
put that engine in yet? i did the same thing but opposite, 2001 x engine into a 96 r50. i had to swap the intake plenum, accessory brackets with accessories, exhaust manifolds, oil filter sending unit thingy and replace a motor mount and thats about it. yours should be easier if you have a body lift and such. we had it done in a weekend as i had to drive it home 70 miles. i kept the 01 dizzy, intake runners, and the r50 valve covers since the newer ones were dented in a bit. most of the time was spent disassembling the old engine just to get to the torque converter, (piston skirts and rod parts jammed in places they shouldnt have been) and then mounting the engine back in the truck and getting the trans to line up, be patient it'll go lol .

DamnHippie
02-08-2007, 06:11 AM
The work has begun, in slow motion. It'll pick up this weekend as parts begin to arrive. Today I should get most of them, timing belt, water pump, all that stuff, plus new plugs and wires and other miscellany. I've got a Mean Green alternator and a body lift kit on order from AC, they might arrive today or tomorrow as well.

Speaking of body lifts, I've been wondering what makes the most sense:

- Engine now, lift later.
- Lift first, then engine.
- Remove engine, lift, install engine.
- Do it all at once.

It seems like there's some ways where a body lift would make things easier -- better access to things near the firewall and such. On the other hand, it'll be harder to work across higher fenders, the engines would have to be lifted higher to clear the body, etc. I can't decide what to do.

I'm also a bit intimidated by the auto-trans part of the work. I've pulled engine/trans apart for manual trans several times, but I've never done anything like that for an auto. I'm a bit hazy on how the torque converter mates to the engine and how to get them apart.

JayRyan
02-08-2007, 07:31 AM
Is the engine coming out of your Frontier a 33?

I want the cams and the intake manifold. :D ...unless Tyler had dibs on the bitch.:rolleyes:

ChefTyler
02-08-2007, 09:19 AM
Tyler's got dibs on everyone's bitch :D

Oh, wait...the motor...nope they're yours JR! ;)

JayRyan
02-08-2007, 10:12 AM
Tyler's got dibs on everyone's bitch :D

Oh, wait...the motor...nope they're yours JR! ;)

Thanks Tyler!

Hippie- sent a PM

elementalvoid
02-08-2007, 10:46 AM
Jay,

I've got an intake manifold you can have today..

PM me if you want it.

elementalvoid
02-08-2007, 10:47 AM
dammit post whores.. you are all too fast.

ChefTyler
02-08-2007, 11:30 AM
JR is only 29 behind me, catch OPW (that's Original Post Whore)!

Anyone have an exhaust manifold from a VG33 or VG30? (know what I'm thinkin' about Tyler?)

JayRyan
02-08-2007, 12:25 PM
Jay,

I've got an intake manifold you can have today..

PM me if you want it.
WERD!

And Tyler, you a good post whore, You don't add much :laughing:

nissandoms47
02-08-2007, 03:23 PM
you'll want to swap your intake manifold to the qx4 engine..

DamnHippie
02-08-2007, 05:06 PM
you'll want to swap your intake manifold to the qx4 engine..

Why? I kinda like the Infinity logo.

nissandoms47
02-08-2007, 10:38 PM
because they're different, but i guess you can modify the infiniti one or whatever. mainly the difference is vacuum lines and the way things were routed. but it might swap. im just saying that because the xterra one was different from the r50 one. the xterra one had no egr so i had to swap.

CHAVEZ
02-08-2007, 10:55 PM
- Engine now, lift later.
- Lift first, then engine.
- Remove engine, lift, install engine.
- Do it all at once.


I would recomend doing the body lift first then work on the engine. It made a world of difference for me. I could litterally reach behind the engine from the engine compartment to get all the bellhousing bolts.

DamnHippie
02-09-2007, 11:06 AM
because they're different, but i guess you can modify the infiniti one or whatever. mainly the difference is vacuum lines and the way things were routed. but it might swap. im just saying that because the xterra one was different from the r50 one. the xterra one had no egr so i had to swap.

Hmm, by casual eyeball I thought they looked pretty identical, but I guess I'll know for sure once I get the old engine pulled and have them side by side on engine stands where I can look at them in real detail. Worst case will be some minor parts-swapping I guess; the IACC on my old engine was begining to die, and I had some suspicions the TPS was acting flakey through part of its range too. That one especially I didn't wanna swap/mess-with because it seems like getting it adjusted just right will be a bitch.

I think after we work on Clay's steering this afternoon I'm gonna try to get the truck into the garage and get started on pulling the old engine.

Packman5280
02-09-2007, 11:46 AM
let me know if you'll be working on it this weekend, I could come by and give you a hand.

DamnHippie
02-10-2007, 09:52 AM
Today I'm gonna be putting the timing belt and water pump and all on the new engine, then I'm gonna see if I can round up a couple friends on this side of town to help push the truck into the garage. If all that goes fast and smooth, I'll begin removing the easy around-the-edges stuff (radiator, power steering pump, etc). If all that went well, I'd start the big pull tomorrow.

On the other hand, I'm now on the phone with Jeff, and his Subaru DD is acting stupid, so he's gonna wanna come over and work on it. I may get nothign done on the truck this weekend.

Packman5280
02-10-2007, 05:39 PM
i was going to work on the honda today, then my roommate called and he blew a u-joint out of his rear drive shaft, so I went and helped him and got nothing done on the honda, so i know how that goes. but we did get the mustang running, should be able to pull it out of the garage either tomorrow or next weekend at the latest.

DamnHippie
02-10-2007, 09:17 PM
I actually did get a bunch of progress made today. The fluids are all drained, the radiator and other small misc things are out. I could be pulling the engine by early tomorrow afternoon.

Or I could be totally puzzled about how to get the transmission disconnected from the engine -- I notice there's no access/inspection plate on the bottom of the bell housing, so I have no idea how the torque converter detaches from the back of the engine if you can't get at it.

Anyway Jamie, I might be needing some help Sunday; gimme a call if you've got some free time tomorrow.

nissandoms47
02-10-2007, 09:33 PM
you have to take the starter out and then the little plate thing and then turn the engine with a breaker bar or something to access the 14 mm TC bolts.

Packman5280
02-11-2007, 08:54 AM
gonna go change the plugs and wires and oil, then I'll give you a call.

DamnHippie
02-12-2007, 12:26 PM
Just a quick update for anyone who cares...

Jamie came over yesterday to help, and we made a ton of progress.

Everything that connects the engine to the rest of the truck is labeled and disconnected (electrical and vacuum lines).

We got the exhaust manifolds disconnected from the cats on both sides. Jamie used just the right mix of patience and muscle on the driver's side. I wasn't quite so good with the patience thing on the passenger side and snapped off one of the studs. Hopefully once the engine is out I'll have easy access to drill it out and put a new one in. (Actually I'll probably put in new studs and nuts for all of them, they're pretty rusty.)

After Jamie left I got to work on removing the starter. What freaking nightmare, it took about 2 hours. I have a feeling this is a nasty job on a brand new Fronty, but it's extra nasty when your engine blows chunks out the side so that all the brackets and motor mount and stuff are bent twisted metal. Much of the trouble came down to the starter motor wires being all pinched between mangled metal. I had to cut the small wire finally.

Then I wasted a bunch of time trying to figure out how to get at the torque converter bolts through the starter opening. Once I realized the metal plate that was in the way was removable it was a nightmare getting at the bolts, again because of twisted brackets being in the way of where wrenches might go and stuff. Even after getting all those bolts undone, the plate wouldn't budge. Eventually I had a Blinding Flash of the Obvious, and realized that plate wraps all the way around the bottom of the bell housing and two more bolts are holding it on the other side of the truck from where I was working.

At that point I decided I must be too tired to continue and knocked off for the day. Still, it was a pretty good day, progress-wise. The exhaust removal could have been way way worse than it was. And the disconnecting-and-labeling project, while a bit tedious, is going to pay off in the long run. In fact, I'm actually feeling somewhat confident that I can get the new engine in without needing expert help on the hookups.

Packman5280
02-12-2007, 01:11 PM
so all that's left is to actually get the TC unbolted, remove the trans (do we need to maybe slide it back away from the engine?) then pull the motor, right?

I wish joel had labeled everything when he took the stang apart, would have been much easier to put things back 3 years later.

nissandoms47
02-12-2007, 01:58 PM
yeah i should have made it more clear about the metal plate lol. how did you get at the bolts? i used like a 20" extention and went in through the front of the truck and it took me less then 5 minutes to get the TC unbolted. and why did you remove the exhaust manifolds with it still in the truck? i found it easier when the engine was removed.

DamnHippie
02-13-2007, 06:03 AM
I haven 't gotten at the TC bolts yet, but I'm hoping the long-long extension trick from the front will work. I'm not sure if the mangled motor mount bracket from the blowup will get in the way.

I haven't taken the manifolds off yet, we unbolted the manifolds from the cats. My Haynes book said to unbolt the cats from the headpipe, implying that they come out with the engine. I'd rather leave them behind if I can, separating the cats from the headpipe just seems like more opportunity to snap off rusted studs. (The configuration on a 99 Frontier is engine->manifold->cat->headpipe->y-pipe->etc. There aren't primary/secondary cats like later years or California models had.)

nissandoms47
02-14-2007, 01:11 AM
man i can see that being a slight pain to line back up with the new engine, but might give more room. my 96 is set up like that pretty much, engine>manifold>cats>downpipe thingy>exhaust tube>dual in single out muffler>tailpipe, just make sure you have a good hold of those TC bolts when they're coming out and going back in

Packman5280
02-14-2007, 06:50 AM
with the manifolds, we can always loosen the exhaust lower down to allow them to move a bit to line up with the manifolds

DamnHippie
02-14-2007, 07:33 AM
There's actually plenty of play in the part being left behind, I can move the cats around about 8-10 inches in any direction. In fact, I had to put one of the bolts back in just a bit on the passenger side to hold it up out of the way while I work around the starter and TC bolts.

I finally got at the TC bolts last night, and got one out. That seemed like a good stopping place, but getting the rest out this evening will only take a few minutes now. There was yet another bent bracket, one holding the AT cooler lines, that was stopping me from moving that plate between the engine and transmission. I had finally decided (reluctantly) that the cooler lines would have to come out to make progress, and when I got enough of it loose, the bent bracket revealed itself and then eventually I got it out of the way. Luckily I hadn't gotten as far as removing the cooler lines where they connect to the AT yet.

DamnHippie
02-14-2007, 08:10 AM
Here's one of those fun little things that makes any engine swap a unique task... This is the fuel line hookup on my old engine (that runs from the hardlines at the fender to the fuel rails on the engine):

http://img224.imageshack.us/img224/9741/1002821xx7.jpg

Here's the fuel rail connection on my replacement engine:

http://img224.imageshack.us/img224/6397/1002822um4.jpg

Unfortunely, I can't just cut the complicated connector off the end of my existing line and use a clamp to attach the rubber part to the fitting on the new engine, because that metal bit at the end is pretty long, so the rubber alone won't reach far enough.

I'm wondering what that fuel line looks like on a pathfinder/qx4, on the hardline side. I forgot to take a picture of that part. On mine, it's a high-pressure flare fitting, similar to a brake line (but bigger). If it's the same on a qx4, then I could prolly just order a stock qx4 fuel line and throw my old one away. If it's got some other kind of connector on the hardline side, then I'm gonna have to do something all custom-fab-like (which might be fun, but doing homebrew redneck engineering on fuel lines is a bit scary).

nissandoms47
02-14-2007, 04:20 PM
yeah i ran into that same problem but backwards, on the end of the fuel like on the side that unbolts, there is a metal fitting, i figured it would just be a regular pressure flare fitting and that i could take off the metal clamp, and i was right. so i just used the xterra fuel line with the stock pathfinder fuel lines.

pics-

http://i86.photobucket.com/albums/k107/nissandoms47/P1010036-1.jpg

http://i86.photobucket.com/albums/k107/nissandoms47/P1010037-1.jpg

DamnHippie
02-16-2007, 06:09 AM
More progress...


http://img265.imageshack.us/img265/3687/1002826pt9.jpg

Packman5280
02-16-2007, 06:57 AM
nice, how'd the leveler work out? did you have to make the tabs for the engine like you talked about?

DamnHippie
02-16-2007, 02:14 PM
Yeah, I made lift tabs that bolt on to the oem lift points using some 3/16 bar stock. On my first attempt I tried to make a keyed slot that holds the chain the same way the load leveler thing does, but it was coming out really bad -- I was trying to drill a series of holes then cut out the bits between them to make nice neat slots. But it wasn't neat, it was a mess and it didn't seem like it'd hold the chain securely enough. So I just drilled some 1" holes and bought a couple 2-ton hooks to put on the ends of the load leveler's chains.

The load leveler itself was totally worth the $20 it cost. While removing the bolts that hold the transmission and engine together, it was handy to crank the leveler so that the engine was lifted a wee bit and twisted over sideways a bunch to open up access to the bolts on one side at a time. It still took a long damn time to get all 6 bolts (and the crankshaft position sensor) out, but I'd probably still be trying if I hadn't been able to easily tilt the engine back and forth.

Stubby~CC
02-17-2007, 01:38 PM
LOL, you got another engine stand. :D

DamnHippie
02-18-2007, 09:55 AM
Yeah, Harbor Freight has the stands on sale for $40, that's cheap enough to not even have to think about it. I had a premonition that having the engines side by side on stands (rather than having the old one laying on a palette or something) would be handy, and I was right.

I got my day off to a bad start yesterday. I thought I could use a regular gear-puller to get the harmonic balancer off the old engine (the new engine doesn't have one). Then I learned that thing is cast iron, not steel. I learned by breaking it. That's a $150 mistake, and car-part.com says nobody in Denver has one, so I'm gonna have to buy a new one. Grrrr.

Yesterday I got the new water pump, thermostat, and timing belt installed on the new engine. Then I started comparing the two engines in detail and began the process of swapping everything that's different over from the old engine to the new. Most of the bracketry is different, but easy to swap. A bit of a surprise was the oil filter mount thingy -- they're way different between the two engines, but totally easy to swap.

A difference that isn't a totally easy swap is how I ended my day yesterday. This is the old engine:

http://img501.imageshack.us/img501/2557/1002829sg6.jpg

This is the new:

http://img103.imageshack.us/img103/3733/1002828dl0.jpg

Notice that the pipe that returns coolant to the top of the radiator has two temperature sensors on the old engine, only one on the new. Worse, it isn't like there's a plug in the sensor hole that I can remove and swap sensors, that spot on the pipe was never milled out on the new engine, so I've got to swap the whole pipe. To do that, the cam timing gears have got to come off, to allow removal of the splash guard behind them, which blocks access to the pipe. And all of that has to be done on both engines. I figure it's gonna cost me most of the day today.

nissandoms47
02-18-2007, 11:41 AM
you dont have to swap that pipe, the easier thing would be to extend the harness to the sensor. that sensor that is missing is the coolant temp sensor. on some r50s they relocated that sensor to the passenger side lower intake manifold. if you look by the injectors you can see it there. i think you should just lengthen the harness. but thats just me.

DamnHippie
02-18-2007, 08:57 PM
Hmm, I just went out and looked, I don't see it (and I have the upper intake manifold off so that things are easy to see.)

Anyway, too late, today I swapped the pipe. It turned out to be a good thing I did... when I took the cam sproket off on the right side, it turns out the oil seal was leaking there. The other oil seal and the crankshaft seal look virtually brand new.

So I go get a seal (I have two parts stores within a 90 second walk from my house, kinda handy) and when I'm prying the bad one out, I notice it's not really in very straight. Then after it's out I notice there's a gouge in the cam, and it wasn't mine -- I was really careful. Whoever replaced it last time did a pretty bad job.

I was able to put the new seal in further, the gouge is now outboard of the seal, so I don't think it's gonna leak anymore.

So now everything is done on the new engine except the upper intake plenum and all the sensors and crap attached to it. I've gone over the whole rest of the engine and swapped out all the brackets and stuff that were different. Tomorrow I'll have a look at the intakes and see if they look identical enough to use as-is, or if I'll need to fully or partially swap them.

nissandoms47
02-18-2007, 10:37 PM
sounds like quite the job. i was working non stop for 2 days to get mine in. would you be willing to sell some of the parts that you dont use? if the intake manifolds are different i could use the QX4 one. but anyways the sensor should be on the lower intake manifold. at least thats where it was on my friends 98 r50, and they should be the same.

this is from the FSM.

http://i86.photobucket.com/albums/k107/nissandoms47/CTS.jpg

DamnHippie
02-20-2007, 05:36 AM
I spotted that coolant sensor when I looked in the light of day. Now I'm a bit worried...

Its wire joins the bundle that comes out to the plugs in that diagram right above the word "ON". That bundle stays with the engine (at least, that was my plan). But now I'm worried that the pinouts on those plugs aren't going to be the same.

I'm gonna have to spend some quality time with the factory service manuals. Maybe there'll be a couple unused pins on my plugs which is where that sensor comes out on a pathfinder and I won't need to swap that whole harness over.

The wiring diagrams in the FSMs make my brain hurt.

nissandoms47
02-20-2007, 12:02 PM
nah all you need to do is swap harnesses to the frontier harness and you should be good. thats what i did but the opposite because the xterra harness, one of the 2 plugs were bigger and it wouldnt plug in, even though there werethe same amount of pins. nothing to worry about really.

nissandoms47
02-20-2007, 12:02 PM
oh and are the intake manifolds the same?

DamnHippie
02-20-2007, 06:56 PM
Yeah, upon reflection I decided swapping the harness would be safest, and I don't think it'll be at all hard.

Today was a day of rest, truck-work-wise, other than running around buying some things (ATF, oil, etc), so I haven't looked closely at the manifolds yet.

DamnHippie
02-26-2007, 07:39 AM
Time for an update, I guess. Also, this message may ramble on for a bit because I'm just gonna dump out a bunch of random notes in case someone stumbles across this thread in the future and is also doing a swap between a Frontier/Xterra engine and a Pathfinder/QX4 engine.

At this point the engine is completely ready to drop back in except for one thing: I need to get some new exhaust manifold-to-engine studs for the right side. It turns out that not only are the manifolds different between models, so are the studs. The Frontier uses longer studs in about half the holes, and a couple of them are in different holes in the head than on a pathfinder. Of the 5 longer studs that came out of my old engine, only 2 came out clean enough to be reused.

Swapping the wiring harness mentioned in the previous posts (the one that goes mostly to all the fuel injectors) was trivially easy. While I was at it I made a pseudo knock sensor out of a pair of resistors (470k + 47k) I had laying around. The knock sensors on both engines were bad. Imagine that. I know I don't need a functioning sensor in a NA engine (especially at altitude), but it only took 5 minutes to solder a couple resistors in its place to avoid the codes in the ECU.

Both engines had EGR systems, but the tube to the manifold was a different shape, so I reused the old one.

The intake plenum was a wee bit different between the two. Nothing too major, you could make it work if you needed to. The biggest difference was that one of the evap solenoids is mounted on the plenum in a pathfinder, and is mounted on the fender wall on a frontier. A hose and wire could be extended. Another difference is that the pathfinder didn't have a vacuum throttle opener for starting the engine. It's a silly little thing but over the years I've fallen in love with that feature (probably because I'm old enough to remember flooding an engine trying to start it). Mainly for that reason I decided to just swap the intake stuff pretty much intact instead of making the new one with the cool Infinity logo work.

The oil dipstick also had to be swapped. They look real different, the pathfinder one isn't nearly as S-shaped. It turns out that the difference in manifolds mandates the different shapes. The dipsticks are pressed in. To get them out don't twist on the tube, it's pretty weak. There's a thick flange thing right where it goes into the block, grab that with some vise grips and twist back and forth while gently pulling upwards on the tube, it'll work free. When I put my old tube in the new engine the fit didn't seem very snug (I think the flying shrapnel inside the engine bent the end of it a bit), so I used a dab of rtv to seal it.

It's kinda funny, when I bought the engine what I wanted was a virtually zero-work drop-in engine. I though the differences between the pathfinder and fronty engines would be so minor that's what I had. In fact, I effectively bought a long block. While I did it a piece at a time, I had the new engine down to a bare long block and swapped over everything, I mean everything, except the block, heads, and lower intake manifold.

But I'm not bitching, I've been having a great time. I haven't done this much major mechanical work on a vehicle for about 30 years, it's been fun. And engines have changed a lot, so I've been learning a lot in the process.

nissandoms47
02-26-2007, 02:11 PM
yeah i left out some details like the dipstick and stuff. but ill buy that qx4 intake off ya if you want to sell it.

DamnHippie
03-05-2007, 07:47 AM
Well, more progress... Martin came over Saturday and helped me put on the body lift. We got everything done except the bed and I finished that up on Sunday.

Now it's time to drop the new engine in. I think doing the lift while the engine was out was a big win in several ways. The steering shaft fought us a bit on the lift, and having the engine out of the way really helped with that. More importantly, it looks like the connections between the engine and bellhousing are gonna be a zillion times easier to do after the lift. I'm thinking I'm gonna be able to just reach in and thread bolts in by hand instead of doing the remote control with 28" of extensions on the socket thing we did to get them out.

If I had it all to do over again, I think I probably would go for the "do everything at once all intermingled" scheme for lifting and engine replacing. If I had done the lift while the engine was disconnected and almost ready to come out, getting the bellhousing bolts out would have been a lot easier.

DamnHippie
03-14-2007, 07:36 AM
Time for another rambling update here... Last weekend was installation time, and it was a major problem-solving opportunity.

Two more differences to note between frontier/xterra and pathfinder/qx4 engines. The O2 sensors are different. Actually I think the sensors themselves are the same, but the frontier ones seem to be inserted into a bushing that adapts the skinny threads on the sensor to the huge hole in the manifold. Over time the bushing and sensors become as one, so if you're doing a cross-model swap like this, plan on reusing the ones that fit your old manifolds.

Then there was the big big difference: The oil pan sumps on the two engines are shaped differently. I already knew that, but it turns out the difference is way significant.

By mid-morning Saturday I had the engine in and bolted up to the transmission, torque converter, gusset plates, and starter, and decided it was time to bolt down the engine and transmission mounts tight (I had them loose so I could move the engine a bit to get at bolts easier). The transmission mounts didn't line up to the holes in the crossmember, by almost a half inch. Oh crap.

After some looking around, I realized the oil sump was up against the front axle tube, and there was no way the engine/tranny were gonna slide forward at all. So the engine had to come back out. Grrrrrr. Swapping oil pans was not an option, my old oil pan has more holes in it than a swiss cheese. I didn't want to order a new one and wait (or pay walk-in sucker prices at a local dealer), so I used a persuader (4lb sledge) with judicious force to make the qx4 oil sump be shaped a lot more like the frontier one. I was able to flatten out the big bulge that the frontier sump doesn't have, and I'm pretty sure I did it without tweaking the oil pickup tube inside (it seems to hang out into the middle of the sump, not follow the edge down).

It also appears to me that the frontier sump is wider side to side while being narrower front to back than the qx4 model. That makes me think that putting a frontier motor in a qx4 might lead to different clearance problems. Or maybe not, but be aware of the potential problem if you're doing a cross-model swap.

The engine went back in and there's just barely enough clearance now to allow all the mounts to line up correctly. I think there may be just a hint of contact between the top of the axle tube and the part of the sump where it curves into the main part of the oil pan. I'm gonna fix that with a poor man's diff drop as described by Allen in another thread.

By the end of Saturday I had the engine mostly physically mounted again. On Sunday I finished bolting things up and began reconnecting everything. This is where the hours spent carefully disassembling and labeling everything really paid off, because it all went back together without any hassles.

Sunday evening I turned the key and it started right up. It took a scary-long time to build up oil pressure enough for the valve lifters to stop clacking. Like 60-90 seconds, but it felt like an eternity. I was starting to think that I had destroyed the oil pickup tube with my bashing. But eventually the oil got everywhere it needed to be and the engine settled down to a nice quiet purr.

Right now I'm at the stage of being hypersensitive to every little sound it makes, but in general I think it's running even better than my old engine did pre-hydrolock. I've got a couple more evenings of odds and ends to fix up before it's ready to wheel, but in general I'm about ready to hit the trails. It's gonna be a kickass summer. :bannana:

nissandoms47
03-14-2007, 08:14 AM
i guess the frontier front axle takes up more space, on my X engine i knew they were different but i said screw it and the oil pan gave me more room above the front crossmember. looks like you had some trouble r50s ftw lol.

Packman5280
03-14-2007, 10:47 AM
nice work Ian, glad you got it done.