Got another one! Project: PolarXJ

[6DoF]

finally found a proper set-up for manual, mechanical VNT control. boost rise rate, a max set point for on the throttle, and a separate max boost for no/low throttle giving better efficiency while cruising. instead of the electric version below, i have a pneumatic limit switch that i'll place on the throttle linkage.

[6DoF]

so the more i research, the more i like compounds and wastegates vs the whole variable geometry stuff. slightly more money, but should be the most capable.


i never realized the grill of an XJ comes off that easy! 8 easy access bolts and one giant plug ... done, off. i basically tore the whole thing apart before i figured it out. the easiest way to access the coolant drain is to just remove the grill like it was some under-tray at an oil change. i love this little thing even more now.

got all kinds of parts sitting here waiting for their moment now. i pulled the radiator to start fitting in the intercooler. the interwebs says i need to move the rad back about 1", so we'll see what shakes out. should be easy enough with the mounts it uses and the way shorter engine.

slowly combining parts from both engines into one functional mess. i'm pretty sure i have at least one of everything that's good!

major work update would be the fuel tank ready to back in. all cleaned up, new sock, new filter/reg, and i added a return line from the injection pump to the jeep sending unit. it's a 90deg bulkhead barb'd on both ends from amazon, was perfect. the washers and threads for the bulkhead are sealed with PTFE sealer, then i smeared on the blue RTV as an additive topcoat just because extra. i learned on the TJ that the return HAS to go back into the can if you don't want fuel starvation issues from slosh at 1/4 tank or less. this should do quite nicely.

i just want to wire brush and ChassisSaver any spots of surface rust now while the tank is out.

[Cobound]

Sam could tell you a thing or two about tearing apart XJs

[6DoF]

Originally Posted by Cobound

Sam could tell you a thing or two about tearing apart XJs

oh i've called him before on questions, even on this one in the early stages.

[Cobound]

Ha, ditto!!

[6DoF]

A few days ago i got the whole area above the fuel tank cleaned n coated with chassis saver n rattle can. Tonight i knocked out a ton of stuff.

- fuel tank installed
- drilled out the fuel filler flap for diesel pump
- injection pump return line run
- auto pedal out, clutch pedal in!
- clutch master holes drilled
- clutch hydros installed
- tcase shifter removed
- tunnel cleaned n auto cover removed

I also had a little sensor adapter made and it's awesome! The VW has an o-ring fit coolant sensor with a clip, while the jeep sensor i need uses an NPT. Adapter n bam.

[6DoF]

been a little while since i got to make a mess with the grinders actually, this was a good weekend!

started off by getting the bolt-in motor mount support brackets removed to make room for the new TDI ones. realized that the drivers bracket was also some support bracing for the track bar bracket ... wanna keep that. chopped up the bracket to it's most basic support for that and got it in paint. this now bolts in completely separate of the new engine mounts.

then moved on to getting the intercooler mounted. picked this dual pass on amazon before realizing it's actually the most common XJ intercooler used, but requires moving the radiator back. easy enough with this crazy short motor, it's only body to worry about. the lower mounts are a basic tab to move the rubber grommet back 1.25", then the upper mounts i moved 5/8" in the mount at the rad, and another 5/8" in the mount at the core support. i wanted to be able to get a new radiator easy later. had to clearance some of the surrounding sheet metal, but it was all non-structural gap close-out sheet anyways. the intercooler mount is 5/8" power steering hose over the post mount, slid into a steel tube. rubber mounted ftw, so the upper is the same 5/8" hose up to the core support and just a bolt clamping it down.

[6DoF]

got the track bar brace re-installed, got everything painted, and even enlarged one of the holes in the cross structure to run the intercooler piping thru.

i think the jeep is ready, need to turn focus to the TDI now and get the pump installed and timing figured out. also need to clean out an intake and the head ports, then modify the intake. need to swap the turbo, new t-stat, and a few 0-rings before i start getting the trans on/in.

since i pulled the front pumper ... i'm really thinking i should just buy a decent non-winch rock bumper.

[6DoF]

got the engine i'm using more cleaned up last night and some paint on this side before the intake and turbo go on. valve cover cleaned up better than i expected.

decided to try and modify the intake for the new 2" boost tubes. i was going to have to buy or make a flange adapter, but realized if i just cut the flange and a tie brace off it's the same thing! pic of my spare engine for stock intake reference. i also cut down a mounting block cast into it, then drilled and tapped it for a boost sensor and a boost reference line to the pump and wastegate controller.

[6DoF]

busted out lots of little things last night, just kept working even after the wife went to bed.

got the intake and turbo installed, just not the oil feed line yet waiting on a cooling line oring. but that oring bore is all cleaned up nice. got the trans adapter installed and the complete jeep clutch, fit perfect! starter with infinite clocking was cool, got it assembled and placed. new water pump, all new idlers, t-stat and oring, even got the crank cog swapped over from the other engine.

while getting the MTDI pump on, what a pain that was though. the bottom bolt is virtually impossible to get to, took all my fingering skills. also had to cut out some clearance in the pump bracket, but she's installed! i didn't realize the timing for a VE style pump involved a dial indicator, so that'll be a thing to learn the technique on now too. i didn't buy "the tool" cuz all the reviews were horrible.

installed the valve cover cuz i can see the timing marks with the vac pump removed, but need to get back in it to TDC the crank. VW puts the marks on the flywheel and bellhousing, so i don't have any. best method i've come across is sticking a wooden or plastic shim in under the cam to extend a valve, and rotate the crank til it hits and stops. place a mark on the new flywheel, then turn it back around the other direction til it stops again. make a new mark, and you can then count teeth between and get a real TDC.

[xj_man_646]

Making pretty good progress!

[6DoF]

i want the engine bolted in the jeep this weekend ... running if possible.

[Cobound]

You'll be rolling coal in no time

[6DoF]

It's in! kinda. ended up at the range for a while Saturday, then a car cruise with Hank, and excuses #3.

so after quite a bit of moving and thinking and rearranging and thinking and staring at it, i found where it'll live for good. i was actually able to get the transmission back onto the factory mount in the factory location! i could get the engine about 1" higher if i drop the trans mount by an inch, but meh. the last picture is actually hood clearance before i moved it down an inch to get the bell housing off the tunnel. this way any XJ kit or parts bolt in no question.

so the trans mount is in/done, and i have the engine mount kit with the block and frame side plates done, just need to fit and weld in the rest. fuel lines are right there and i need to get it started and make sure i don't have to screw with anything while it's back out for mount welding/paint.

[6DoF]

mounts are tach welded, she's holding her all the weight!

i was a little unsure of the universal mount kit i got for the XJ and TDI, but they worked out really good actually. only a few little trims to fit where i was putting it and weld it in. they are nice and solid too. goal for tonight is to get them out, fully welded, and in paint so that tomorrow i can bolt the engine in for good.

while it's out, i also need to make some plates for the exhaust flange and EGR block-off.

once weight went back down on the springs, it did compress more than i was hoping it would have. given the shocks are kinda junk, but i can bounce the front by hand and get the oil pan to touch the axle housing. now i need some pretty substantial bump stops, and a lift to keep some up travel. i'm debating how to do this ... cheap with pucks and who cares, or spend the money for some dual rate coils to stiffen up the ride compression and just work better over-all.

[6DoF]

uuuugghhhh ... i really didn't want to redo this whole thing right now ... ordered a complete lift with dual rate coils, and all new CAs ...

[xj_man_646]

Well, that escalated quickly!

I am surprised that there are the clearance issues given that they came with the 4.0L.

[6DoF]

Originally Posted by xj_man_646

Well, that escalated quickly!

I am surprised that there are the clearance issues given that they came with the 4.0L.

with the overhead cam, that adds some height over the stroke length ... but the big issue is the oil pan depth. the oil pump is in the front of the engine and hangs below the crank. pan could be like 4" higher over the axle with a rear pump.

[6DoF]

big weekend for the little XJ! starting with me playing hooky on Friday and spending the day working on it.

i runs! and works on the key!

fuel lines built, fuel PSI regulator installed ... but it's REALLY not the right unit for this. pressure pulses back from the injection pump when shutting down leave it at like 50psi in the line/IP and over 20 can blow out the front seal dumping fuel down the timing. even no lift pump, just drawing fuel, it'll shut down with 20+ psi in the line. i had to buy a regulator with return line. will be here tomorrow.

cut out a turbo down pipe flange and an EGR delete cover. made a coolant hard line that runs up along the intake to make a fwd connection vs the one at the back of the head. i was annoyed that the throttle cable coming out of the firewall was like in the way of where i needed to bracket the cable to the pump, so i looped the cable and zip-tied it to itself. the firewall is now the hold point and it's perfect.

messing with electrical some, jumped the NSS for now but will most likely put that on a hidden switch. found a nice key'd power source under the hood in a connector i'm not using. the computer must be missing grounds cuz it doesn't want to do anything yet though. starter wire works though! got the 3-in-1 EGT/boost/fuel psi gauge placed and wired on the dash.

also got the B&M cable t-case shifter installed, the NP231 installed, rear drive shaft is in. clutch slave hooked up and clutch confirmed functional. fixed the brake lights staying on issue. drivers seat re-installed.

egt probe was actually kinda interesting to install. i forgot to drill/tap the manifold while it was out, so i put it in the EGR blockoff plate instead. it came with a 90deg bend outside the compression fitting that holds it to the manifold ... had to bend the stright, slide it up, then re-arc the probe to get deeper into the manifold. worked out pretty well thought i think.

so the very first fire up i had the new gauge facing out the windshield so i could check running fuel pressure. bleeding injectors ... crank ... bleed ... crank ... more cranking with smoke ... finally gave it throttle and it hit a few times. YES IT"S GOING TO WORK ... cranking ... throttle and it lit off and ran! quickly look around for what the fuel PSI is and there's fluid splashing all over the INSIDE OF THE WINDSHIELD!! SHUT IT DOWN SHUT IT DOWN. ... no shifter in the trans so the gears flung some new lub all over the dash, steering wheel, door, windshield ... uuuuggghhhhh that sucked to clean.

[xj_man_646]

Originally Posted by 6DoF

with the overhead cam, that adds some height over the stroke length ... but the big issue is the oil pan depth. the oil pump is in the front of the engine and hangs below the crank. pan could be like 4" higher over the axle with a rear pump.

Ahhhh that makes sense.