Q451990 wrote: ↑

Tue Mar 22, 2022 9:42 pm

I've learned a lot just researching what's "ebay-able" and really enjoyed using quality stuff instead of my previous collection of Harbor Freight specials.

I've picked up a lot of used high-end tools at garage sales over the years - the difference in quality and usability over some junky new Chinese-made garbage makes it a no-brainer.

Ryantzer wrote: ↑

Tue Mar 22, 2022 8:21 pm

The ABS unit on my 1990 has apparently been leaking for some time, as the mounting bracket has bubbling paint and rust forming on the area beneath the unit. I found a used unit that was completely dry from another 1990 and have it ready to install in the next few weeks when the rest of the brake system is getting an overhaul. Good to know that a rebuild is not outside the realm of someone with decent mechanical skills, should the used unit end up being a leaky mess as well.

Yes, Im surprised other members haven't attempted it before considering just about everything else has been done. That being said I dont have the torque specs or any information regarding assembly so who knows how this will turn out LOL

Q451990 wrote: ↑

Tue Mar 22, 2022 9:42 pm

Knipex Pliers, and Nitrile Gloves - in this messed up world, they both cost about the same thing! We won't even mention the Snap-On ratchet. As a buddy of mine used to say "rich guys doing rich things..."


In all seriousness, I've spent a good bit of the last year sorting through a lot of vintage tools that I inherited from my Dad. I've learned a lot just researching what's "ebay-able" and really enjoyed using quality stuff instead of my previous collection of Harbor Freight specials.

Ikr! Gloves are getting pricey, $25 a box last time I checked. Feels better raw, but you gotta wrap it up!!!

In terms of tools, we use plenty of HF, you just have to know what not to buy. Im still using the same impact sockets I started off with. Other Pittsburgh stuff like their torx and allen sockets break instantly. A quality tool saves you time and sanity.

I stopped by the specialist this afternoon for lunch. It took him a while to measure everything and not all is an exact match. The majority is going to be the closest equivalent to what is available today. Heres the list of every o-ring for the system. A couple were special order so i wont get them for another week and a half maybe.


We did come up with one problem. Where the solenoids are seated are some wide rings. He was not able to find an equivalent in the material needed so he gave me a regular Buna (nitrile) ring which should be a good fit. According to him it should only swell a little when it comes into contact with the brake fluid. So, since they are sandwiched in between two pieces of metal, they aren't moving around and risking being sheared, I have to do some materials testing to make sure it doesn't disintegrate. If it swells a little then perfect. That would help it seal a bit more and might be even better than the original material in that regard. In the meantime I will soak a couple of rings and test how they react while waiting for the rest. No word on price yet, said I could pay when the rest of it gets here. Exciting stuff.

Are there seriously 51 o-rings in that unit? That's insane!

Ryantzer wrote: ↑

Wed Mar 23, 2022 1:41 pm

Are there seriously 51 o-rings in that unit? That's insane!

44 to be exact, 5 extra for materials testing and 2 extra on a bolt sheath (minimal importance, its like a dust cover). There was no exact fit and the measurement was perfectly in-between 2 sizes. Thats the only one I have to sort of "feel out" and use my best judgement.

So, looks like ive got plenty of time for additional mods before the car is back on the road. Received an incomplete timing kit and the modulator is on hold. I was thinking about a star-liner like they have on Rolls Royce. A kit from amazon is about $200

Another thing that has saved my truck plenty of times is a train horn. You would think that a bright red plow, salt spreader and reflective caution tape would stand out just a little . Too many careless people on the road and a regular horn doesn't always cut it.

Is there any other major upgrade im missing? Injectors replaced many years ago when I first got the vehicle. I picked up some knock sensors with the harnesses just in case. The sunroof is now functioning, got the antenna going, new sound system, fuel pump is replaced. Suspension bushings are beginning to crack but should last me through the summer.

I'd focus on the trans next (can't recall if you said you had done work there already or not).
Most '90s did not have the pan with the drain plug, although it may have been retrofitted over the years. I'd drop the pan regardless, and clean the magnets and replace the screen. then I'd add a stacked plate cooler (the zenkei's only had a single tube radiator cooler, while the kouki's got two tubes, and also an external filter). Then find the TCU out of a '93 for first gear start.
You have the RE4r03A with the wide ratio gear set!

3Q Jay wrote: ↑

Thu Mar 24, 2022 7:33 pm

I'd focus on the trans next (can't recall if you said you had done work there already or not).
Most '90s did not have the pan with the drain plug, although it may have been retrofitted over the years. I'd drop the pan regardless, and clean the magnets and replace the screen. then I'd add a stacked plate cooler (the zenkei's only had a single tube radiator cooler, while the kouki's got two tubes, and also an external filter). Then find the TCU out of a '93 for first gear start.
You have the RE4r03A with the wide ratio gear set!

Thank you, great suggestions! Never would have thought of an external filter, thats definitely getting done. Now to find a reasonably priced TCU. I see one that's 94+ but apparently that's overshooting the sweet spot according to some older posts.

Bored to tears waiting for parts. Decided to do the valve covers after all, the oil stains were starting to bother me. Turns out one of the reman injectors is clinging to life @ 22 ohms. The plenum hoses are going to be major fun of course.

I've got a spin-on filter kit and cooler that I have plumbed out and ready to drop in for the trans. Thank you 3QJay

No1Dad wrote: ↑

Sat Apr 02, 2022 10:49 am

Bored to tears waiting for parts. Decided to do the valve covers after all, the oil stains were starting to bother me. Turns out one of the reman injectors is clinging to life @ 22 ohms. The plenum hoses are going to be major fun of course.

I've got a spin-on filter kit and cooler that I have plumbed out and ready to drop in for the trans. Thank you 3QJay

Your Q will be providing many years of enjoyment with only the usual mx items after you complete all this 'remedial' work.
Since you are digging into the lower plenum, I would recco changing out your knocks while in there, and for sure the coolant hoses in the valley.

Oh, and I believe a TCU from a 94 or 95 will be just fine for you as well, but double check. For sure the FGY33 TCU is different, even though they use the same interface connector. And a 96 *might* be different due to OBD-2, but again, you will need to check to be sure.

3Q Jay wrote: ↑

Sat Apr 02, 2022 11:25 am

Oh, and I believe a TCU from a 94 or 95 will be just fine for you as well, but double check. For sure the FGY33 TCU is different, even though they use the same interface connector. And a 96 *might* be different due to OBD-2, but again, you will need to check to be sure.

You're absolutely right. I dont want to touch this intake again for a while LOL. Found the post I was referencing. Should be fine for the most part. Seems to be related to the gear ratios you mentioned earlier. With parts of scarce as they are I might as well just have it on hand anyway.

Any updates on the ABS actuator? How has your qualification test on the buna o-ring submerged in DOT 3 gone?

3Q Jay wrote: ↑

Wed Apr 13, 2022 6:17 pm

Any updates on the ABS actuator? How has your qualification test on the buna o-ring submerged in DOT 3 gone?

I keep getting told that they should get here "late next week" whenever I call to check. I will start looking online if they don't arrive by Monday.

The submerged o rings seem to be holding up well. Theres one that I've been mangling a couple times a week, another that has been compressed between two coins, and the last is just chilling. So far the "swelling" has been negligible @ 2.6% (1.90mm vs 1.95mm) Ill measure them again soon enough to check for expansion and signs of decomposition. At this point I'm sure they're fine......

No1Dad wrote: ↑

Thu Apr 14, 2022 10:05 am

I keep getting told that they should get here "late next week" whenever I call to check. I will start looking online if they don't arrive by Monday.

The submerged o rings seem to be holding up well. Theres one that I've been mangling a couple times a week, another that has been compressed between two coins, and the last is just chilling. So far the "swelling" has been negligible @ 2.6% (1.90mm vs 1.95mm) Ill measure them again soon enough to check for expansion and signs of decomposition. At this point I'm sure they're fine......

fwiw, I have ordered several times from
https://www.oringsandmore.com
they have a lot of EPDM in metric sizes.
good to hear on the qual test. I'd try to split one also by expanding it to about 120% of nominal diameter.
Did you do anything with the solenoids on the actuator (test them?)

Good idea Ill try that next. The only thing that concerns me is long term usage. Who's to say they will last a few years from now? Disintegration doesnt usually happen overnight. No, the ABS system was working flawlessly before disassembly so it didn't occur to me to test them.

In other news I'm just about done buttoning up the rest of the vehicle. I checked the injectors and the spray patterns were looking bad 6/8 were leaking as well. Some pressure cleaning took care of it for the most part. I ordered an injector for a '90 300zx. Apparently they use the same one as the Q45 but the compatability chart doesn't list them as a possible fit. Its also new and I wont have to worry about shoddy remans.

By the way you saved me some serious heart ache. No clue why I didn't spring for the valley job while I was there but the hoses were leaking a fair bit and those knock sensors (+harness) were toast. That explains the intermittent lack of power all those years back.

The unit is assembled and has been installed. However I did goof on the solenoid placement. My mistake really only seems to have an affect on wire routing so I'll be leaving it as is for the time being. I know it actually matters in terms of pulsing the brakes and keeping the vehicle tracking straight but the focus right now is leakage. Ill have to get the vehicle plated and drive it around before calling it a success but i dont see any seeping right now. Id say the outlook is good.

good to hear! keep us posted.
make sure you get a solid "buzz---thunk" when you pass 3 mph on initial start up/drive-away. (ABS self test).

3Q Jay wrote: ↑

Wed Apr 20, 2022 11:19 am

good to hear! keep us posted.
make sure you get a solid "buzz---thunk" when you pass 3 mph on initial start up/drive-away. (ABS self test).

Maybe I spoke up too soon, everything seemed to be going well until I decided to really push the ABS system. I set down some sand in the rear parking lot and started going at it. After maybe 10 minutes I noticed some seepage. The solenoids themselves may be leaking. I see dampness around their flanges (joint??). Oh well. Back to the drawing board.

The car itself is definitely a trip. I decided to take it out for an evening spin and as I was sitting outside the gates to the shop adjusting mirrors, setting the temp, etc; power to the seat control suddenly gave out. I was close enough to the shop where I decided to check it out real quick and there is no voltage at the yellow wire but the fuse is fine and it has batt voltage. Great whatever nbd.

I'm driving around with the windows down to air out the years of stale air. And I s*** you not both the rear window regulators go out. The trans definitely needs a rebuild on top of all this.... Talk about a passion project!!

What is the age and condition of the transmission fluid? I’d be inclined to do a fluid change before assuming it needs a rebuild, unless you’ve already done that.

Ryantzer wrote: ↑

Wed Apr 20, 2022 6:46 pm

What is the age and condition of the transmission fluid? I’d be inclined to do a fluid change before assuming it needs a rebuild, unless you’ve already done that.

Unfortunately yes. Its on the 3rd fluid change since I started working on it a few months ago. I've put in 50 miles today and i noticed a minor improvement but its still slipping out of 2nd gear under moderate acceleration. I'll try an additive but I'm pretty much resigned to the fact that its too late.

No1Dad wrote: ↑

Wed Apr 20, 2022 7:24 pm

Ryantzer wrote: ↑

Wed Apr 20, 2022 6:46 pm

What is the age and condition of the transmission fluid? I’d be inclined to do a fluid change before assuming it needs a rebuild, unless you’ve already done that.

Unfortunately yes. Its on the 3rd fluid change since I started working on it a few months ago. I've put in 50 miles today and i noticed a minor improvement but its still slipping out of 2nd gear under moderate acceleration. I'll try an additive but I'm pretty much resigned to the fact that its too late.

Please elaborate on 'slipping out of second gear'?
are you saying overspeed on the 2-3 shift? (very common with the RE4R03A with age). If true I can make some suggestions.

3Q Jay wrote: ↑

Wed Apr 20, 2022 8:26 pm

Please elaborate on 'slipping out of second gear'?
are you saying overspeed on the 2-3 shift? (very common with the RE4R03A with age). If true I can make some suggestions.

Im open to try anything. I really dont want to start another major teardown

I definitely misspoke earlier. I meant to say i slip out of 3rd. Driving at around 20 mph I seem to be stuck in 2nd gear and if I feather the accelerator I can manage to make it shift without redlining. Otherwise anything more than a nanogram of weight on the pedal will cause it to essentially be stuck in second gear and over-rev the engine until it reaches ~40mph and finally shifts.

At highway speeds I do okay if I'm just cruising say about 60 mph and don't punch it. but if I push the accelerator 75% it down shifts and doesn't actually "catch" a gear. Its like i put it in neutral. Let off the gas and it'll shift.

hmmm, might be too far gone.
but if you want to experiment before tearing down for complete rebuild this would be my list:
1) Do NOT use M1 ATF. generic wally world dex/merc seems to have the right friction properties (at least it works waaay better than M1 in all of mine).
2) do a pan drop and magnet clean, change the filter screen
3) do a few iterations with the 2-part BG products ATF flush and conditioner.
4) replace the shift solenoids on the valve body. don't forget the line pressure solenoid.
5) Try the 93-up TCU. I think you were going to do this for 1st gear start anyway.
6) do the (transgo?) valve body shift improver kit.

3Q Jay wrote: ↑

Thu Apr 21, 2022 7:27 am

hmmm, might be too far gone.
but if you want to experiment before tearing down for complete rebuild this would be my list:
1) Do NOT use M1 ATF. generic wally world dex/merc seems to have the right friction properties (at least it works waaay better than M1 in all of mine).
2) do a pan drop and magnet clean, change the filter screen
3) do a few iterations with the 2-part BG products ATF flush and conditioner.
4) replace the shift solenoids on the valve body. don't forget the line pressure solenoid.
5) Try the 93-up TCU. I think you were going to do this for 1st gear start anyway.
6) do the (transgo?) valve body shift improver kit.

What specific differences did you notice using Walmart fluid vs anything else? I'm running Valvoline Max life. The solenoids and shift kit are a solid next step since I would need them anyway for the rebuild. I'm also running the 93 TCU right now.

Ill go ahead and get on that. I still haven't decided about that modulator. I scavenged a solenoid screen/filter off of the 94. It appears that they share the same components and this unit was dry. I could try swapping the solenoids out altogether. The newer unit is starting to look like a much more practical choice. Ill sleep on it.

the max life might be ok, as long as listed as a dex III replacement (I think it should have MERCON V as a listed spec) it just appeared that the FM package for the M1 'all makes' ATF was not a good fit--at least with clutch pax that had 100k on them already. Symptom was a slipshift with engine flare on the 2-3. maybe more to it than that, but I ditched the M1 after 5 miles cause I couldn't stand the change.
fwiw, i *do* still run M1ATF in the PS circuit of both G50s.
and just to satisfy my troubleshooter brain.....you are running the 93 TCU, and have the desired 1st gear start, but. with your original TCU, are all the other bad shift indications the same as with the 93? Obviously, will be second gear start unless you mash it, or slam the stick over to 1, but the actual shifts up and down?

I'm fairly certain that Dex 6 is fully backwards compatible. As far as friction modifiers and different brands I'll take your word for it

Yes, tried both TCUs and I have the same shifting issues with either one. I did have these same transmission problems for roughly a week before the vehicle was mothballed so it's no surprise. I was just hoping that I could buy some time without an overhaul considering I did not limp the vehicle around for an extended amount of time.

If anyone has more suggestions I'm all ears. In the meantime I'll be waiting for those solenoids/shift kit and I'll report back after I pop them in.

Looks like there's no use fouling those new solenoids! 150 miles later pan drop #3 is not promising. Id say the patient is living on borrowed time. This one is definitely the worst so far.
RIP @97k

Icing on the cake is some chain noise at 5k RPM (down from 7k). Luckily its the driver side tensioner so its not that bad. AND a couple of struts just went out. Might have to take a brief hiatus for morale. I expected a stupid amount of work but its like playing whack - a - mole

That's very sparkly! Too bad sparkly isn't a good thing in this case.