Anglin's Road Car Projects and History

[anglin]

The motor mount replacement, transmission mount replacement, driveshaft replacement job is finally complete. The project turned out to be substantially more involved than I anticipated, mostly because of the problems that occured along the way, not the actual work itself.

I'll start off with motor mount replacement.

The driver's side motor mount has been broken since before I owned the car. The previous owner actually autocrossed and drag raced the car (it ran low 13s with the mods he had done to it) with the mount broken and the hood shows the damage from the throttle linkage whacking the hood.

Additionally, I didn't want to put my semi-rebuilt driveshaft in the car with the old saggy mounts. Instead of just replacing the broken motor mount wuth an equally sagged used mount, I decided to replace the motor and transmission mount with new parts. At the Carlisle 2006 dinner banquet I traded with a guy who wanted what I had in exchange for the Rapido reproduction transmission mount that he had one. To show my gratitude for Rapido's support of the Carlisle dinner banquet, I ordered a set of motor mounts from Rapido to go with the transmission mount.

Rapido motor mount (right) and T-bird motor mount (left) that I have modified by drilling out and tapping the top plate and then installing a length of stainless threaded rod


old motor mount on the passenger's side (note lack of AC compressor)


How can you tell if you have a broken motor mount? If the driver's side mount is broken, the most obvious indicator (with a manual transmission car) is how the shifter handle will roll to the right under heavy acceleration in first gear (higher horsepower cars will display it in other gears as well). There are no obvious physical signs if you just pop the hood. Jacking the engine up (carefully) will also lift the engine off the mount.

old driver's side motor mount, no obvious failure visible


There are a handful of ways to hold the engine up off the mounts to replace the motor mounts. The shop manual shows a bracket that supports the engine from above by bearing the weight on the fenders. You can also support the engine with an engine hoist. I lifted the engine with a jack and a block of wood. My method is almost certainly the least safe of all the options. Taking thoughtful precautions can help mitigate your risk.

screen grab of engine support fixture from shop manual


I removed the motor mount by removing the nut from the lower stud from underneath the car (17 mm, IIRC) and removing the three 15 mm bolts holding the aluminum mounting ear to the block.

broken driver's side motor mount out of the car


Since the Rapido motor mount isn't a direct replacement, some small changes need to be made. The plate that the motor mount lower stud passes through has a hole that is sized for the M10 stud of the stock mount. The Rapido motor mount uses an M12 stud. A 1/2 inch drill bit fixed this problem.

new mount, unmodified plate


new mount, modified plate with the hole enlarged using a 1/2 inch drill bit


The stud in the top of the Rapido motor mount didn't appear to have been installed quite far enough so I used an extra washer under the split ring lock washer to be sure the nut didn't bottom out on the stud.

comparison


Installing the mount, especially on the driver's side, proved to be a substantial challenge of my coordination. The bottom stud has to be put through the hole in the front crossmember while the bottom plate is held in position and the aluminum mounting ear is positioned near its three bolt holes in the block and manuevered around the power steerting pump, the TFI hanging off the distributor, the ignition coil and the knock sensor which wants to dig into your forearm (unless you have little girly-arms).

It is helpful to loosely install the nut that holds the motor mount to the aluminum mounting ear, as pictured below.

motor mount assembly waiting to be installed


I tightened up the bolts in the following order:
- aluminum mounting ear to block
- top stud nut
- bottom stud nut

Even though there are no alignment/anti-rotation pins on the Rapido motor mounts, I didn't have a problem with the motor mount rotating as I tightened the nuts onto the studs. If you do have a problem, just putting the weight of the engine back on the motor mounts should hold everything in place.

motor mount fully installed waiting on the coil, TFI and knock sensor to be reconnected


I'll add the transmission mount replacement steps next along with the driveshaft alignment process. In the meanwhile, review Don Sweigert's driveshaft alignment process:

http://www.angelfire.com/pa3/lyzcoinc/alignshaft.html

[anglin]

Okay, time for another boring intermediate post. I installed the transmission mount after the motor mounts. This is when the project started to fall apart a little bit.

It is completely possible, though annoying, to replace the transmission mount without dropping the exhaust. Your exhaust may affect the procedure. I've got the Borla dual exhaust on my road car. However, because I was replacing the driveshaft, the exhaust had to come off the car. I'll get into the trials and tribulations of the exhaust system in another post.

The procedure was straightforward once the exhaust was removed. I supported the weight of the transmission with a jack. It seemed like it was appropriate to remove the two 13 mm bolts holding the transmission mount to the crossmember first, so I did. One of them broke. It seemed like a big deal at first, but turned out to not be a problem. Then I removed the four 13 mm nuts holding the crossmember to the car. The speedometer cable passes through the crossmember, so it isn't being completely removed without taking out the cable. I didn't have my snap ring pliers with me (T9 transmission), so the cable stayed connected and I replaced the mount while I was under the car.

As mentioned in a previous post, the Rapido transmission mount uses 5/16 inch bolts instead of the stock M8 bolts. In spite of the fact that I am annoyed that I have inch-sized fasteners on the car now, it was a semi-lucky thing because my brother-in-law is a muscle car guy with a stash of inch-sized bolts. I snagged two from him. I would still have rather gotten two new M8 bolts if the Rapido mount used metric nut inserts.

Then I reinstalled the crossmember. That is basically all that is involved in the replacement procedure. However, when I get to the driveshaft alignment portion of this task, you'll see that I wasn't done with the transmission mount yet. Here's a preview:

As it turns out, the Rapido motor mounts are taller than the stock mounts. This isn't terribly surprising, given what we know about the mounts. However, because they are taller, the CSB has to be shimmed downward to get aligned. Way downward. I was running out of threads on the CSB to chassis bolts. So, I shimmed between the transmission crossmember and the transmission mount to raise it up. I'll give more detail later. For now, enjoy the pictures.

old transmission mount prior to me messing with it


Rapido reproduction transmission mount, bottom view (notice the 5/16 inch holes instead of M8 holes)


Rapido reproduction transmission mount, top view


Rapido reproduction transmission mount, top view with plate that transmission mounting boss rests on removed (it drops in)


proper mounting orientation

[anglin]

Alright, I'm still not done with the driveshaft replacement project write up, but I'm temporarily switching gears. When I finished the driveshaft project and drove home (did the work in my brother-in-law's four car garage), it was 10°F outside. I've been having trouble with a sticky heated seat switch since last winter.

My XR4Ti has spent about 2 years of its life, in the time I've owned it, sealed up and stored outside in the summer sun while the military had its way with me. As a result, a lot of the interior plastic is brittle and the lubrication on switches has become too thick to allow proper operation. The switches for the rear defrost and rear wiper got renewed last winter (page 1 of this thread) because they started to fail. The heated seat switch stayed on 95% of the time in the winter, so it wasn't a problem before the recent cold snap.

When I went to turn the seat heater on, the switch wouldn't budge. Finally it gave way and the switch just flopped back and forth. The seat heater didn't turn on. I knew it was time for disassembly.

guts of the switch (non-broken)


As you can see from the pictures below, the terminal that the switch mechanism rocks on was bent (lower and right switch). This allowed the rocker to come loose.

good switch (top) and broken switch (bottom)


top view of switches, good (left) and broken (right)


A pair of needle nose pliers bent everything back into shape. If this happens to you, be sure to test out the rocker for smooth operation when you put it back in. The tabs on the terminal on either side of the rocker that keep it from falling out may become deformed when you are bending it back into position which will prevent the switch from operating smoothly.

Just like with the defrost and rear wiper, I cleaned and relubed the switch assembly before putting it back together. They work beautifully in the cold now.

[anglin]

Well, it's been two months without an update to this thread and I still haven't finished wrapping up the details on my driveshaft installation and alignment and the entertainment that was the exhaust trouble that went with the driveshaft job. I'm going to further distract from that conversation, too.

I was messing around with some Group-N upper strut insulators with the senior design project and realized what a PITA they are to install. I did it back in 1998 or so when I originally did the suspension work to my racer, before it was the racer. Well, I remembered the trick to putting the upper strut insulators in and took pictures of the process the other day. Here they are:

tuck part of the lip in


hold it in place (I'm making it look easy)


slide the bushing in place


pop the lip back out


Tada!

Keep in mind that you don't have to do this with the stock or two-piece polyurethane upper strut insulators. The stock ones are so soft and compliant they practically jump in the holes.

[BeefFajitas]

Is the 1027 the build date stamp? I swear my car isn't stamped, I can't find anything on the strut towers.

[anglin]

Is the 1027 the build date stamp? I swear my car isn't stamped, I can't find anything on the strut towers.

Yep. I believe it's called the paint code date or something like that.

Did work today converting from winter to summer mode. Got the snow tires off and the Kumho MXs on. Yay! Here's a series from the time lapse feature on the camera.



Too bad I couldn't swap out the rusty panels for unrusty ones so easily.

[tvissoc]

How can you tell if you have a broken motor mount? ............... There are no obvious physical signs if you just pop the hood.

Other than the dent in your hood.

Did you use the T-Bird SC (fluid filled) mounts? That's what I did with mine.

Tony

[anglin]

Did you use the T-Bird SC (fluid filled) mounts? That's what I did with mine.

I used Rapido's liquid filled mounts. Here's my quote from the post:

Rapido motor mount (right) and T-bird motor mount (left) that I have modified by drilling out and tapping the top plate and then installing a length of stainless threaded rod

[anglin]

Been a while since this thread has been updated. With the winter weather upon us, I figured I'd better fix a problem my road car has had for a couple years - a wiper arm linkage that falls apart in use.

The link that connects the motor to the wiper arms has had a worn bushing on one end which allowed the linkage to pop off at inopportune times, like when it's raining. It wasn't a steady problem, so I forgot about it on several occasions, but with a real commute possible in my future, I figured I'd better take care of the problem.

My solution was to make a tab that prevented the linkage from separating. I made the tab out of 1/16th inch thick alumimum. It's not a great long term fix, but I did the task from beginning to end in about 2 hours. This fix should last through the life of the chassis.

The linkage connecting the arms to the motor is the point of failure. Here's the car with the cowl taken off.


The failure point looks rusty, but normal.


The two halves separate easily.


The tab was cut with a 0.5 inch diameter half-circle in it. The narrowest section of the ball on the linkage was about 0.45 inch. The tab was bolted to the linkage with two M6x20 bolts and two stainless nylock nuts.


You can see the space between the tab and the socket, made possible by Ford's design team. They identified what the failure was going to be and how I would fix it and designed the offset in the linkage accordingly.


The width of the space inside the linkage was perfect to prevent the nuts from rotating as I tightened up the bolts with gear wrench. This is an awful picture, but I didn't know it was until five minutes ago when I took the images off the camera. So, it's the best you're going to get.


The bolts were tightened up once the linkage was regreased and assembled. The gear wrench made quick work of it.


Here's another angle of the final assembly.


That's it; two hours work and I even got to clean the part of the windshield that hides under the cowl. Of course I broke all 6 plastic fasteners that hold the cowl to the car, but I knew that was going to happen in advance.

Will this repair wear out? Sure. Is it perfect? No. Given the condition of the rest of the car, it suits the car well. I was hoping there would be some sort of worn out nylon bushing in there, or something, but I could really tell what the socket was made of. Honestly, I can't say thay I was terribly concerned about it. I'll get thousands and thousands more trouble-free wipes from the system now.

[anglin]

And I'm back with more updates. I've been troubleshooting the poor heat in the car since it's about to become my home for two hours a day on a long commute to and from work. I flushed the heater core, replaced some hoses and, most importantly, I put in a new Motorcraft thermostat, replacing an aftermarket thermostat.

Before and after I did the thermostat swap, I monitored the temperature profile over time to see what the difference was. I was astounded at the difference in behavior between the two. It's all documented here:

http://forum.merkurclub.com/forum/viewtopic.php?t=15972

In addition to the humdrum work, I also put a new (to me) head unit in the car with an auxillary jack and new front speakers, I swapped out the stock steering wheel for a Sapphire Cosworth steering wheel, just for fun and I tightened up a bunch of loose screws in the hatch area to cut down on rattles.

Currently I'm swapping out front TCAs. That's going to be a good story to share when I'm done with that project.

[anglin]

Currently I'm swapping out front TCAs. That's going to be a good story to share when I'm done with that project.

Here's the story. I ordered left and right hand side TCAs, Dorman parts, from Rock Auto. I disassembled the car and unboxed the TCAs to install them. I held the TCAs up side-by-side to see which one went on which side, only to discover I was holding two right hand side TCAs. It was Friday afternoon and I needed the car Monday. The PNs on the box correctly reflected the left and right hand sides, but the contents of the box were wrong.

Rock Auto would only ship a replacement after they confirmed that I had sent the wrong one back (when Fedex scanned it into their system). That wasn't going to be very quick, so I instead ordered two left hand TCAs from Autozone, and now I have a spare set of TCAs. Considering Autozone's price difference (see below) between left and right TCAs currently, I might be saving a decent amount of cash over the long haul.

Dorman 520-271 (left) - $64.99
Dorman 520-272 (right) - $99.99

I would have done a screenshot, but I can't upload it right now.

So, the Autozone/Dorman left TCA was installed last weekend, an alignment was performed and the car is back on the road.

[anglin]

The car had a no-start related to the J3 chip this morning. Here are the details and (unconfirmed by thorough testing) solution:

http://forum.merkurclub.com/forum/viewtopic.php?t=16339

[anglin]

The car had a no-start related to the J3 chip this morning.

That J3 chip was setup with stock PF3 maps except the cruise rpm threshold for the closed loop to open loop switch point. The plan was to increase fuel mileage with this chip. Since I removed it last week, I've put two tanks of gas through the car and can post some preliminary fuel mileage numbers.

Removing the J3 chip setup for fuel mileage has reduce the fuel economy of my road car by about 0.5 mpg. As I get more data over more tanks I'll report further results.

[Ray]

0.5 mpg can also be attributed to things like ambient conditions.

[DPDISXR4Ti]

0.5 mpg can also be attributed to things like ambient conditions.

Amoung other things. A .5 MPG difference across a sample size of 2 is not statistically significant.

But I got a "C" in statistics, so what do I know!?