Trouble Removing the Fuel Rails

FurryWrecker911

SCCoA Member
I have a problem, and I'm hoping it's a case of me just undoing the wrong fastener. I have a 1989 SC, and I have the 4 torx screws and fuel injectors nice and loose, but the rails are stuck at the fuel pressure regulator. Haynes manual is only good for the V8 and non-supercharged V6, and it says it's just a bolt holding it to the back of the block. Well, I found a 13 mm nut on a stud in the same general area, and undid that to no avail. I came on here to see people saying it's a 15mm bolt which I could not find while I was down in the garage.

Alright so what's the deal, did I undo the wrong fastener or were the 89s special and used a nut and stud instead?
 
For the fuel pressure regulator at the back of the head, there is a stud w/fixed nut/nut stack. The outer most nut on the stud clamps a heater hose bracket/clamp, then with those out of the way, there is also a fixed nut on the stud that clamps the fp regulator bracket to the back of the head. The stud needs to come all the way out...not fun. I did some of the work from the top, and some from below, depending on if coming apart or going back together.

An articulated socket wrench and just the right deep socket helped - not a lot of room to use wrenches. I bought a double-jointed flex head socket wrench to get it done. Might be one of those flex-head ratcheting wrenches would work.

Helps to slot the fp regulator bracket on re-assembly, or so I've heard.
 
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For the fuel pressure regulator at the back of the head, there is a stud w/fixed nut/nut stack... ....The stud needs to come all the way out...not fun.

Dang, I was afraid of that being the case. I have a swivel head ratchet wrench set that should do the trick nicely once I get the heater lines out of the way. Any advice on how to pull those back? I didn't get a good look at them yet, but they felt pretty firm in place.
 
Still stuck.

I need to make sure I got this right because I finagled with it today and got nowhere. So to disconnect the fuel line (orange) I need to disconnect a vac line (Red) and to do that I also need to disconnect a neighboring vac line (blue) and pull them away and hope they don't bend or break in any way? I feel like I'm missing something obvious because I haven't seen anyone complain about this on here. This is a lot of work for head gaskets...

And yes, I realize now they are not heater lines but vac lines. I had a difficult time following them with my inspection mirror.

89SupercoupeFuelRailRemoval.png

Actually for that matter, do the studs function more like that or more like this?:

89SupercoupeFuelRailRemoval_v2.png
 
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There is just one vacuum line leading to the regulator, should be easy to reach and not an impediment to removing the regulator - flexible, sure, durable, usually. Just don't go crayCray yanking on it. If those lines are fragile, you've got other issues.

Pull the line with the right angle rubber fitting that goes onto the metal nipple on the regulator and let it hang, then remove the nut holding the heater hose bracket, then the stud. Regulator should come away easily at that point. The hard part is getting the stud out, I think, not the regulator once the stud is out.

Vacuum line 'red' at the regulator is one thing. Blue is to the manifold, I think, and not specifically involved w/removal of the regulator at this point.
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remove the nut holding the heater hose bracket, then the stud. Regulator should come away easily at that point. The hard part is getting the stud out, I think

Vacuum line 'red' at the regulator is one thing. Blue is to the manifold, I think, and not specifically involved w/removal of the regulator at this point.

And herein relies my problem. Red line is the line that shares the FPR stud. It's a metal tube and it feels pretty firm in place even with the nut gone. I can wiggle it up and town a tiny bit, but I can't pull it away from the stud with my bare hands. My deduction was seeing that red was also mounted at blue led me to believing I had to undo blue as well. If you're saying what I have done so far is on track then Idk how to pull the red line off without using a prybar. Here's a video from last week showing off all the more I can move it:

https://youtu.be/N79a1xQrRzA

Not exactly the most polished video I've ever shot, but that's what I got.
 
When I said the regulator should come away easy, I meant as part of the fuel rail, once the stud is removed. And just to stay on the same page, red in your drawing is heater hose/coolant. Blue is trans dipstick? Orange is fuel.

Video helps, thanks.

The bracket and metal heater hose will be in your way at all times at this stage - there is very little horizontal~front/back working room. I seem to recall another captured bracket on the pass.side, but I don't remember if it had to come loose to help deal with the lack of front/back clearance when trying to remove the stud that clamps the FPR to the driver side head...both need to eventually come off so you can pull both heads, tho. If it provides latitude to move the bracket on the stud, and allows less bending, and you can reach, then go for it.

See if you can get in there with an open end and break the stud loose...the shank that threads into the head is surprisingly way long (left blue double-ended stud in your drawing would be flipped end/to/end), and you'll be spinning it out for a while if you take whacks at it with an open end, which is why I just 'persuaded' the metal hose bracket off so I could come at it with a deep thin-wall socket, working from below.

Also, looks like the ground for the injector harness is still secured by a bolt. That wire end/grommet needs to be free so the harness comes out with the fuel rail, as an example. Don't forget to put it back when going together, or the engine won't fire.

Tried to add this image to the last comment...not sure it helps much except to show the bracket flush against the head.
 

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Tbh I'm not 100% sure what blue is supposed to be, but yes, orange is fuel, and red is heater (I think. It might be vac because it leads to an open ended rubber hose on the passenger side? I need to double check in the morning. I also need a new inspection mirror). Blue is just a dry open top tube as it sits now. I need to go back through my tear-down videos to see what it hooked into. If that's where the trans dipstick is supposed to be then HOO BOY I'm in trouble. Here's a still image from the vid I posted:

whateverthisis.png

As for the passenger side bracket that might be the one I have drafted up holding the blue line/red line combo down. Regardless, I'll look for any additional brackets, and see if freeing them up will help. The ground strap also has those lines in the way so it's on my "get to after this" list. Haven't tried approaching from underneath yet, so I can give that a try. Exhaust manifold needs soaked in some PB anyways.

I can attempt to pursued the pipe out of the way as well and shimmy a ratchet wrench down in there. Already done that to break a few others loose on this. haha! Is the stud nut 15mm?

Thanks for the reference image. Looks like what I was expecting based on the manual's images. That would have been far nicer just undoing a single bolt and it'd come right up. Tbh I'm strongly considering going to the hardware store next door after this and getting a bolt and spacer to replace the stud and nut. This is more difficult than it needs to be.
 
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I want to say I used a deep 13mm on the stud.

Suggest you remove the wiper motor assembly to help overall access.

Is that the EGR tube in the red square?

P I T A, yes. Right up there with changing plugs, power steering pump replacement, and front seat cushion removals.

Welcome to the joys of SC ownership.
 
Funny you should say that because the wiper motor is shot (runs but it sounds like a dying robot) and needs replaced while I got the top end out of the way.

EGR tube... maybe? Manual shows an example image from the NA V6 and it has the same wire mesh sleeve. I don't remember disconnecting it though.

lol thanks for the support. I'm beginning to understand why you never see these anymore.


Edit: OH, SO, I just found out through the TBSC Shop I'm missing the EGR Diaphragm! I recognize that tab on the left being sandwiched to the passenger side head stud with a 13mm nut while trying to help in loosening the heater line! Well, uh... HMM.
EGR-Diaphragm.png
 
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Step-by-step...

When I did my headgaskets in 2018, I had over 2 dozen other things I wanted to deal with that I kept putting off until I was in that far. Added to the repair costs a tad, but I didn't want to find myself thinking how I should have also done xyz later. Not that bad of a job after you've done it at least once ;)

I went back thru my notes and photos from the job and it looks like it helps to have both the left and right heater hose pipe brackets unbolted from the heads before going after the stud. Pass. side bracket points down, driv. side up. I think, when reassembling, get the driver side bracket on the stud first, then bolt the pass. side up. My '90 Anny lacks EGR, so can't comment on it.

I'm beginning to understand why you never see these anymore.

I was browsing the free ads on local craigslist recently, and noticed someone was giving away an old pop-up camper. I spotted a black SC in the same photo, outdoors, sitting in low weeds, and when I asked about it, they said it was parked there when it blew headgaskets - they told me they'd sell it, no title, no other info. It's on a farm about 1/2 hr. away and I plan on going out to at least take a look, sometime next week.
 
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The hose you're having issues with is the coolant line they ran thru the throttle body housing in 89 and early 90 models. It connects into the heater hose on the the drivers side. I personally wouldn't worry about being gentle removing it. Also once removed throw it as far as you possibly can along with what I (and I think others over the years) have labeled as "hell bolt". Source a later model driverside heater hose once you put it back together.

When I did the head gaskets on the 89 5 speed I own it gave me the same trouble. Did head gaskets on the orginal motor at 200k miles in 2015 or so. From memory though I can not remember socket sizes but a short socket was too short and a deep well was too big for the space. To make matters worse 89-92 had the massive braking system also fighting for the real estate.

Wish I could help more. On these cars it's usually an 8,10,13,15 or 18mm ...real helpful I know.

-Tim
 
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