Scion xB Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
i buy, fix and sell....stuff. i mostly do ATV's and motorcycles because they are small and more of them fit in my garage. but i pick up cars if they are a good deal and seem profitable. now, i do not 'bandaid for profit' i do quality work even if it means i am going to make less profit. this work is a side job for me and i enjoy it.

through a series of trades i ended up with a 2006 Scion XB. it looked in not bad condition but was not running. the owner was not mechanically inclined and through his description i thought it needed a fuel pump. besides...its a toyota, how bad could it be?

77592



i get it home and start trouble shooting. new battery, add some fresher gas to the tank. new spark plugs, fresh oil, hit the key... it doesnt sound bad but definately does not start. check for fuel and find that it is getting fuel. check for spark, it has spark, welp, lets grab the compression gauge and see what it looks like. the highest the gauge gets across any hole is 90 psi... and hole 4 is blowing coolant. shiat, head gasket.

well i wanted to save some time so i bought a junkyard yaris motor... it ended up being questionable so i did a quick freshen up on it. Prius C pistons, head gasket, valve stem seals, water pump, etc.
77593

77594


and i even got to drive it...for a while.
77595


i was headed to Denver (about a 6 hour drive) the day after this picture. and all was well. i even tooted around Denver for a few days with no issue. however the return trip the engine died for a split second going down I70 and then continued running briefly, and then died. a phone call and a couple hours later and i was back in Denver for another night while the XB slept on the side of I70.

In the harsh light of day i got back out to it and did some diagnostics on the side of I70 (exciting as semis rip by) and found low (but not near empty) coolant. it cranked and there was no wierd noise but did not start. i grabbed a spare coolant bottle and topped it off and cranked the starter for a while. still no start. checked the coolant and noticed it was back down to where it was before i topped it off. where did it go you ask??? straight into the oil pan. dipstick appears to show WAAAY too much...fluid in the oil pan. shiat.

i RENT the crappiest car i can find and trudge home. thinking seriously about just leaving it there. not sure it is worth dragging home, not too mention my tow rig is not really adequate for long distance car towing. (2007 Mitsubishi Outlander with a 2 axle flatbed car trailer. it works for my local stuff i usually do).

well i needed to back to denver the next weekend anyway. i figure i will take the trailer and if it is still sitting on the side of the interstate i will pick it up and drag it home. it will have been about 10 days since i left it, and nothing sits on I70 10 days so i figure its gone, honestly, i don't even feel bad.

so there i am, cruising along I70, 10 DAYS LATER.... and there sits the frickn XB. right where i left it. shiat. as promised, i load it up and drag it to Denver with me. park the entire rig in a wal mart parking lot, and call my wife for a ride. (who is not super excited that it was there might i add.) (you guys are wondering at this point, why i am going to and from Denver, and why my wife is up there with a car. Well my daughter has autism and was in an extended stay at the Denver kids medical center) so the tow rig and scion sat in the walmart parking lot while we dealt with other things. and a few days later i got dropped off at walmart and proceeded to make the (slow) trip back home. the ol outlander did the job. but i didnt push much passed 60 mph, the scion was probably lighter than the trailer it sat on. it was still a fair overload on the poor outlander.

i dumped the thing in my driveway and proceeded to ignore it for a while. finally i figured, i need to decide a plan. well i still have the original engine with the bad head gasket so i will rebuild it and toss it in.
so i do.
77596

head milled but before being cleaned. i also had the block decked, prius C pistons in this one also, countless seals, o rings, yada yada...
77597


theres also a fidanza flywheel in there this time. this is moments before the ORIGINAL engine, now rebuilt, goes back where it cam from.

so i bet you are thinking happy endings and champagne? well i tried firing it up and it did burble once but never showed any signs of life after that. for a day i messed with it. checking fuel, spark, individuel injectors and coils. nothing. finally put a compression gauge and was getting 90, 90, 60, and like just off 0 in the last hole. W...T....F?!?!

i thought maybe i messed up timing (i spun the engine over tons of times by hand but i guess maybe) so i pulled the valve cover...
77598


SHIAT!!! it must have broke the very first time i hit the ignition and then every time i tried to start it after that it proceeded to grind itself into metal and cycle through the engine. at this point i go inside and sit quietly with a nice 6 pack. i also start checking the scrap metal value and figure the 200$ i can turn it in for will at least get me a good bottle of whiskey. but the fidanza flywheel needs to come out. and some how surfing the internet that night i come across a prius C engine with 3000 miles on it for 200$ wait...will the gas engine out of a prius C fit in here? it is a form of a 1NZ... whats different, no power steering pump, electric water pump....WAIT am i seriously thinking about doing this AGAIN...?
 

·
Registered
Joined
·
9 Posts
Discussion Starter #2
yeah, so i am picking up a prius C engine this weekend. pics of the engine to come soon.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #4
IMG_20200301_141440.jpg

the installed cam is atkins cycle, the lobe is much more rounded and longer duration. the yaris cams will be going in. the springs are a different part number, but visually quite similar so i am going to leave the prius springs in place. i suspect the prius springs may have a slightly lower spring weight to them but i am not building a race car and theres only about 1000 RPM difference in the redline of the 2 engines so i am going to run it and see. (typically i would change the springs out, but i am getting tired of tossing money into this pit so this is getting a try it or take it to the crusher last ditch effort)

other minor differences like no waterpump, no alternator bracket (it would have been on the waterpump mount) and watercooled EGR, as well as slight differences in the belhousing mount. nothing that i think cant be remedied. (the prius C engine was dumb cheap, if i can sell the prius c waterpump the engine will have been free.)

benefits: this prius c engine had 3822 miles, comparatively the yaris and other 1nz junk yard engines are 100k plus. My last rebuild was hampered by used cams and i do not want to do a real full rebuild for a 2500$ vehicle. the electric waterpump should free up some horse power, i can not use the toyota one as it is connected to the prius ECU. debating how to handle power steering and alternator. at a casual glance it looks like the power steering pump will bolt up, alternator will need a little work.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #6
i've got a design and plan for the waterpump issue. DaviesCraig makes a nice retrofit electric waterpump, the 80L kit will be going on here. i have also figured out the differences in the plumbing on the 2 vehicles and i have a route designed to make the prius C coolant opening mate to the scion xb. hopefully this weekend i can get the toasted toaster engine out and do some retrofitting on the new engine. the motor mount location on the front of the engine is identical in appearance so that should be fine. also Sensor locations are identical, there are some minor differences in a couple sensors so i will swap in Scion xB sensors.

even if this is not much more than a 1st gen xB with a 2012 engine and electric waterpump, i think this could be a good way to keep some 1st gen xBs on the road longer. the 1nz is a fine engine with some maintenance but people hear toyota and think they don't even need to change the oil.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #7
i spent most of the weekend rebuilding a 40' section of fence so i did not get the toasted toaster engine out. i did have a little time sunday evening to make some progress. the wire loom is disconnected so i am pretty close. i was able to verify the front (passenger side) motor mount compatibility. 3 of the 4 bolts line up perfectly so i am going to run it like that. also i am starting a list of sensors that will need swapped. locations and holes seem to be identical with only minor differences, i think some of them may be compatible but no reason to confuse the 14 year old ECU if the original sensors will mount in the new block.

as always, catch us on the next episode (i am taking pictures but this was exceptionally minor so i will add them when the engine is out and i can do a comparison.)
 

·
Registered
Joined
·
9 Posts
Discussion Starter #8 (Edited)
actually made some progress. for some reason all these damn work from home and conference online initiatives have caused my I.T. department to be swamped. anyhoooo.....

here is the prius c motor with the lower case removed. the scion xb A/C compressor, and starter, will not bolt to the prius c engine. however swapping the xb lower case on to the prius c block fixes both these issues.

IMG_20200322_175027.jpg
IMG_20200323_073454.jpg
IMG_20200323_073508.jpg

also of note is the brass plug. there was a coolant nipple there that connected to the prius c EGR. i thought about using this as a connection for the throttle body, but my throttle body coolant seal was leaking and causing coolant to run into the intake manifold. long story longer, i just plugged the EGR coolant location,sealed up my throttle body coolant intake and looped the line on the throttle body to keep dirt out, and swapped the scion xb sensors over.

NOTE: sensors swapped easily and the connectors are identical, the prius c sensors MIGHT have worked but the part numbers are different and i had scion xb sensors in working condition so i see no reason to tempt fate on this item. if i had known bad scion sensors or any other issue, i think i would try the prius c sensor.

the back side of the block where the long bolt is sticking out, that is only there for me to grab, it is not part of the build in any way.

power steering pump: simply stated, it will not bolt up with out new brackets being made or the scion brackets being modified a fair amount. my plan, as this is a sub 2500lbs car, i am just gutting the power steering and i will be de-powering the steering rack. this will also save some front end weight making it even easier to turn de-powered. i think it would not be impossible to make new brackets for the power steering pump, but why add complexity for minimal gain here? if you do this swap and feel differently, please go the route you desire.

the ONLY other major issue i still face is the bell housing, however swapping the lower case also half fixes this. i think 1 of the upper bolt locations will line up but even then the bolts that the prius c use are substantially different due to the trans-electric drive system being a lot heavier. still i think this is a possible bridge to cross so i have been assembling parts along the way with a completed project in mind.

the top (bottom in recent pics because i flipped it to work on the lower case) is complete with Yaris cams, ARP studs, and timing gear all attached. The ARP studs are a PITA and 3 of the nuts have to be ground down substantially to fit under the cams. and the VVT-i activator has to have the end cut down a bit to fit with the ARP studs. i do feel the ARP studs will be a good investment as the theoretical compression ratio with the prius c pistons and yaris cams will fluctuate between about 11:8.1 and 13:0.1 so while this little box should still get really good gas mileage, it should be a hoot to drive.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #9 (Edited)
notes too myself (or anyone really)

there is a pressure switch that is connected to the power steering system. it looks like is function is 2 fold. it monitors that the system is 'working' IE: has fluid at all. and it also triggers the ECU to adjust idle or shut off the A/C in high load situations. Also, it will trip a code at open circuit and closed circuit, this meens that if i just leave it unplugged or try grounding it out like is possible on idiot lights on the dash, the ECU will pop a code. i found this link below that gives some info on function and i will document my (theory) on stopping code tracking. until i get to this part of the install it will remain theory but i need to document my findings or my brain will boot the info due too.....SQUIRREL!!!


also a post with the voltages but no info on building a harness or if anything was tried.

that document shows us some basic troubleshooting and pin outs. it looks too me like there is an input to sensor, output to ECU from sensor, and a ground lead that probably (hopefully) connects to the body of the sensor, thus equaling ground. the sensor itself is a resistance based sensor and looks to have very few different settings, basically 2 fails being open and closed, and 2 resistances being high and low. the ECU does not look like it cares about exact high or low numbers either. resistance sensors usually are not supper accurate so ECUs are programmed to look for acceptable ranges. before i get into resistance load dynamics and pressure switches vs sensors, i will just state what all this actually makes me think will work as a fake sensor. simply put, a fairly generic resistor between the data pins and ground the third pin out (i will probably make a small harness to plug into the factory clip) should keep the ECU from noticing their is an issue. the concern is getting enough resistance to fall into the standard range of the sensor, and not go open,closed, or high.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #10 (Edited)
made the coolant adapter. it should have been a 0.5" plate, but this 1.5" thick bar stock was all i could find. i did not realize at the time but the extra thickness actually will make it interfere with the stock alternator location. since i have to make a lower alternator mount also, i think i can kick it out a smidgen and gain enough clearance on the coolant flange to not contact a hose. i could have also used a 90 degree elbow on the adapter i made. i could have done lots of things differently, but here we are so i will keep moving forward and make small adjustments as needed.

IMG_20200328_234007.jpg

IMG_20200328_233952.jpg

there was a fair amount of gap to fill in, and it has been an easy 5 years since i had to MIG aluminum. and it was a 1.5" block being welded to paper thin tubing. still, it will hold. i also had to weld and lap the bottom side a little as i used a hole saw to cut the hole, and it was a little different shape then the opening on the block. honestly to make this a true 'home garage' operation, 1/4" mild steel plate and a 1 1/4" steel tubing piece would have worked just as well and fit better under the alternator.

crappy pic of the test fit of some of the coolant hoses. there is a T fitting but it is too dark too see i think, it will have the return for the heater core connected in.
IMG_20200331_220639.jpg

IMG_20200331_220727.jpg
 

·
Registered
Joined
·
9 Posts
Discussion Starter #11
while the car still has the engine next too it, i have been planning phase 2 (stereo) and phase 3 (coilovers). here are my stereo notes.

head unit Alpine Scion upgrade unit from later model vehicle. (pt545) on order.
small customization needed for the USB port but nothing major.
MIGHT need C27 connector mod

Originally Posted by DDStrat

The trick to easily accomplishing the C27 pin relocation was to finally locate the wire pin lock release bar on the wide flat side of the connector (For the electrically challenged, the C27 connector is part of the existing car-side harness that plugs into the back of the head unit… don't disassemble the Alpine unit thinking the mod is to the connector integrated into the head unit.) The pin lock will be on the bottom surface of the C27 connector depicted in Dave90T's drawing. The pin lock is a 1/8 inch strip the width of the connector about halfway back from the end of the connector. You have to look closely as it is same white color as the connector. Use a sharp object to pop it out about 1/32 of an inch to release the lock on the pins. I used a sewing needle. You can then easily relocate the wire pin 14 --which was a gray wire on my 08 xB --to the pin 18 hole (4 holes away). Pop the lock back into the connector and pat yourself on the back for a job well done!

Radio3.jpg

detailed connectors
scionalpine.jpg

front
radio2.jpg

Bluetooth module connected to cd changer port
BTSTY2

MMATS audio class D amp
d200 laying around somewhere from a lifetime ago when i did custom installs

6.5" subwoofer in a hidden box in the rear speaker location.
will be a CT sounds, or rockville, or maybe Skaar, or whatever is on sale (not JL or memphis, i never liked that junk)

fronts will be MMATS components ran off the deck unless i find a nice SQ amp, the head unit is accommodating for either install design.
 
1 - 11 of 11 Posts
Top