To the main gist of the post and my particular problem, here is the pictures of the stuffed up exhaust. What could have caused such crazy rust problems? That is just a baby sampling of all the junk that came out of the resonator when I turned it upside down and shook. Got the muffler off last night and it was just as bad.

 

Great write-up and from details it sounds like you're down to primarily sourcing an entire exhaust. Although oem direct replacement numbers may be NLA you should still ask tech service of major manufacterers if/how they handle needs for acceptable substitutions. From Wiki it shows rear suspension based on the rear-wheel drive 1968–74 X-body platform, so check if there's still active listings for Nova pieces to hack and wack into a fit for the OTA and tailpipes. The normal 350 Olds would either have a Y-pipe or true duals that can be fitted with aftermarket cats? Mufflers can be found by just pouring over the fitment and spec charts of most any maker. Individual mandrel-bent pieces of common curve and angle configurations can be bought to meet remaining challenges filling in the gaps. I wouldn't count on too many chain shops to have mandrel bending equip., but If you round up sufficient pieces to get close then they can weld it all up? T'sall I got, and you sound like you know all this already. Goos luck and welcome to the Cadillac Forums.

 

Aside from the issues with your exhaust, for starters, I'm thinking new tires. Old ones are probably dry rotted, & all fluids, anti freeze oil/filter, check the tranny fluid. If it's red & doesn't smell burnt, you might get away with that. Go from there a little at a time.

 

Tires are on the agenda, but were further down the list of "we'll do them if we have a running car deserving of a new set of Vogues" territory.

The tire situation kills me as those things are Vogues and stay totally inflated without issue and look new in terms of tread depth, but I know it is a safety issue so I will do that for sure assuming I get the car running well enough to justify it.

Brakes I was planning on a new master cylinder (and mandatory fluid flush when installing it) and flexible brake hoses as well as new seals on all the calipers. Pads and rotors are as meaty as anything coming out of the box.
Basically anything rubber is being swapped out. Hoses and brake parts thankfully are cheap.

 

Fun fact as in reading about the Fuel injection issues these cars are prone to I noticed in looking over their service records both the air temp sensor and ECU unit were replaced at the 196 mile mark because the car was cutting out while driving.

I would have blown a gasket at having to replace my cars ecu before I even hit 200 miles. I guess it is why that set-up didn't make it very long.

 

I was going to say radiator hoses as well, belts, & check the brake lines too, especially any part of them that are rubber.

 

If the exhaust looks like that, carefully, carefully examine the brake lines. If there are any areas that show rust, proceed with caution. If replacing one line with rust is part of the equation-- replace ALL lines that have rust. The wall thickness with the rust will burst when you least expect it.

Since you got it running already, congrats are well deserved! Hats off to you!

I'd start it, drive it (slowly) a bit and see what rears its ugly head. A car sitting for years is the worst thing for seals and gaskets. If the power steering seal didn't blow yet, it should be on the list for replacement. I wouldn't worry about much else until you get it drive it a bit and see what rears its ugly head. GM had a good run of rubber/plastic engine parts during this era and if the car sat in a modestly enclosed environment (garage/lean-to, etc.) you might be surprised that things might be a bit better than expected. Wouldn't worry about the hoses and belts -- but knowing an ounce of prevention is truly a cure-- don't plan on driving it far far from home. Small steps. Cracked hoses don't scare me. Even soft fuel lines will typically weep and give you a whiff of gas smell before it seriously leaks.

The brakes would scare me (see prior brake line comment). I'd definitely replace the front calipers and brake lines as cheap insurance (and they are cheap). Wouldn't mess with the rears though would verify that the drum seals are ok and not seaping. Other than that change the oil and suck out and replace all other fluids. Change the fuel filter.. it will have delaminated internally and is probably breaking down after 30 years.

The paint looks AWESOME! Great job, again.

Rock on!

 

If the exhaust looks like that, carefully, carefully examine the brake lines. If there are any areas that show rust, proceed with caution. If replacing one line with rust is part of the equation-- replace ALL lines that have rust. The wall thickness with the rust will burst when you least expect it.

Since you got it running already, congrats are well deserved! Hats off to you!

I'd start it, drive it (slowly) a bit and see what rears its ugly head. A car sitting for years is the worst thing for seals and gaskets. If the power steering seal didn't blow yet, it should be on the list for replacement. I wouldn't worry about much else until you get it drive it a bit and see what rears its ugly head. GM had a good run of rubber/plastic engine parts during this era and if the car sat in a modestly enclosed environment (garage/lean-to, etc.) you might be surprised that things might be a bit better than expected. Wouldn't worry about the hoses and belts -- but knowing an ounce of prevention is truly a cure-- don't plan on driving it far far from home. Small steps. Cracked hoses don't scare me. Even soft fuel lines will typically weep and give you a whiff of gas smell before it seriously leaks.

The brakes would scare me (see prior brake line comment). I'd definitely replace the front calipers and brake lines as cheap insurance (and they are cheap). Wouldn't mess with the rears though would verify that the drum seals are ok and not seaping. Other than that change the oil and suck out and replace all other fluids. Change the fuel filter.. it will have delaminated internally and is probably breaking down after 30 years.

The paint looks AWESOME! Great job, again.

Rock on!

Thanks for the kind words. I was fired up about how well it buffed out. Not a pro by any means, but know enough to be dangerous. The leather seats were actually the revelation compared to how I found them. I literally wet sanded them essentially with the gray and white scotch brite pads to get all the dirt and rat crap off them and then leather conditioned them to death and they look and sit practically brand new right now.

The rear brakes are actually discs as well, so like the fronts I was going to buy seal kits and see where that took me as the friction ring inside is the money on these in terms of them working or not. The rear calipers are also about $90-100 each all in vs. a $6 rebuild kit. They are annoying as well because of the brake spring and emergency brake lever. I remember my Trans Am had this same set-up.

The metal brake lines had that rust coating crap all over them so I am hoping they are likely OK. The exhaust wasn't hit with that stuff, and rotted accordingly I guess. Car was garage kept for its whole life, so its exposure to the elements was non-existent.

I only got it to run for a minute or so before it died, but I wanted that as a baseline before I tore into it so I wouldn't be left wondering if it was me or the car had I done everything I am doing now first and then went to start it and got nothing. Starting it with a fuel tank full of crap is not the best idea, but I always knew that was going to have to be dropped and cleaned to clean out the fuel system. Hearing it run at least told me it was capable of it, so it was safe to proceed.

 

Congratulations on getting your beautiful car running and achieving such a fine "clean-up" already! To encourage yourself, check-out the site "Bring-A-Trailer" and you will find a quite recently auctioned 1977 Seville (Black with gray interior) that brought a hefty price and it had 15,000 original miles--https://bringatrailer.com/listing/1977-cadillac-seville-6/. There is a legion of loyal admirers of the 1975 1/2 to 1979 series of the Cadillac Seville model.

Then consider joining the Cadillac-LaSalle Club for many knowledgeable enthusiasts of these first-generation Cadillac Sevilles and in particular they are familiar with the "early" fuel injection systems standard on these Sevilles--https://www.cadillaclasalleclub.org/page/forum There will also be information in this group about obtaining a new exhaust system for a classic automobile such as yours.

Your car's colors were called Hudson Bay Blue with Dark Blue Vinyl Roof ("tuxedo grain") and Antique Light Blue Leather interior. Similar Vogue Tyres are still available new--https://www.voguetyre.com/ and those were a common accessory upgrade when the car was new. The standard factory specification WSW radial tire is available at diamondback tires-- White Wall Tires & Custom Vintage Tires - Diamond Back Classic Tires

Good luck with your project and thanks for sharing the pictures of such a gorgeous "survivor" and a great Cadillac! Please keep us posted as to your progress.

 

Great job on both the paint and the leather seats. There was a youtube video on the Seville I came across a couple of weeks ago which you may enjoy. It's a somewhat new tech/ improvements piece Cadillac/GM made.

I've been assisting a '77 Seville owner "noodle through" some of his issues on what was his Grandfather's low mileage car. I think he mentioned something like 26K total miles. He was having a somewhat strange issue which sounded like a description I read once on another forum where one of the contributors blamed the Ethanol added gas for a fuel pump issue. The theory was the pump has little lubrication with ethanol containing fuel and the heat generated causes an issue with the pump. He claimed that the car would just stop after running fine. My car isn't my daily driver so I have always used "pure gas" due to the reputation of ethanol on rubber parts and as well the tendency for things to rust during storage. Anyway the owner of the 26K car had a couple of instances which seemed similar and despite changing the fuel pumps. He switched to "pure gas" and hasn't had the problem since. Since your car is new to you I thought I would mention it.

One other thing I didn't realize until about 5 years ago is submersible fuel hose is specific and has it's own standard. So if you replace(d) the soft line in the tank it needs to be specifically submersible.

As far as parts are concerned Bruce Roe is a retired Electrical Engineer and a magician with the ECU's. He's able to fix essentially all of the common issues and he can bench test them. He's very reasonable and worth talking to if you think you have an ECU issue. He also sells an external fuel pump relay which prevents a common issue of one of the ECU terminals from burning out. I posted a thread on another forum showing how I wired his relay on my 1979 such that all of the connection, except for the extra ground, were done using the factory wiring harness plug.

70’s ECU Wiring: Bruce Roe kit install on a 79 Eldorado

70’s ECU Wiring: Bruce Roe kit install on a 79 Eldorado

forums.cadillaclasalleclub.org

I sell replacement coolant and air sensors (same PN). I've tried to address all of the potential failure modes. I've also recently created a replacement for the Fast Idle valve:

Items for sale by punched455 | eBay

Shop eBay for great deals from punched455!

www.ebay.com

One more very helpful link is one to Cadillacseville.org. They have the EFI diagnostic trees posted:

'76 to '79 Cadillac Seville home page

1976 1977 1978 1979 Cadillac Seville information

www.cadillacseville.org

Scott

 

Thanks for the warm welcome everyone.

Well I put in some time this evening and sadly a new radiator is now also in my future. I had had suspicions as the colors along the side of the radiator, the bulging hoses and a cap that was poor fitting all lent themselves to radiator trouble, but I was choosing to be in denial until now.

I was working my way into the engine so I could swap out the water pump and do the timing chain gasket as that clearly had leaked as well at some point (and have on every car I have ever owned) so I bucked up and confronted the radiator since I was there.

As a general observation the hose clamps Cadillac used are resoundingly horrendous as they almost encourage hose bulging and deformation with how unevenly they apply pressure across the hose. It is no wonder they all seemed squirley.

The other evidence I can pick-up that the radiator had done some leaking is that the bottom right hand side of the core support has a rusty build-up that isn't present elsewhere on the car, and looks more like other cars I've had over the years that weren't rust guarded and garage kept. Clearly there has been some ongoing moisture present there. It is in no way rot, but it also sticks out compared to most everywhere else in terms of the body/frame.

I am already hating myself that I can't leave well enough alone, but these problems would manifest themselves probably sooner than later and I have zero interest in doing just enough to get it running only to knowingly leave long term problems that will lead to tearing it apart again.

Knowing how to do stuff is a curse it seems in that it is a blessing to not have to pay someone to do everything, but on the flipside makes it so much harder to blissfully and knowingly half ass it as you know better.

 

I had an '84 Toronado which had a similar looking "radiator support". I think the coating compared to almost everything else was really poor. Hopefully it will clean-up well enough that you can get a coating to last and hopefully the metal still has good integrity in that area.

"Knowing how to do stuff is a curse it seems in that it is a blessing to not have to pay someone to do everything, but on the flipside makes it so much harder to blissfully and knowingly half ass it as you know better." Yes it takes multiples of the normal time to clean everything properly and take care of other things while-I'm-in-there.

It's been a long time since I've tried to get a radiator re-cored. My feeling is it's really hard to find replacement cores and places that can do it. In the case of your car I would rather see something which looks original. The original oil coolers may be better than in an aftermarket aluminum replacement as well. I'll be interested to hear what others say regarding the possibility of getting a Cu-Br core re-cored. I hate to ask the question but I wonder if the heater core is in similar condition and if it's possible to find a Cu-Br. Aluminum are ok if the material selection is good but the issue is there's absolutely no way to look at an aluminum replacement and determine how well a company did with their material selection.

On the timing gear I guess you haven't completed that part of the job because I guess you would have photos of everything painted. You mentioned you had a 70's TA... if it was a late 70's automatic it may have been the Olds 403 and if so you likely already know the job but I'll mention a few things just in case:

• The lower seal on the front cover is shared with the front of the oil pan and it's a real pain to get a new seal in place. A friend and another "Olds guy" told me his trick is to clean the original seal and re-use it with some good gasket sealer. The reason is it's already shaped to fit well.
• There are 2 sizes of fasteners used on the water pump with 2 different torque specs. One size goes into the block and the other only the front cover. The "brilliant" idea was to form the thread for the bolts by forming some of the front cover metal in an effort to provide more thread than the cover thickness itself. It certainly was lower cost but when I have a front cover off of that style I have someone weld real nuts to the back of the cover with the bolt in place as locators.

-The paint - Believe it or not it is really difficult to find that Oldsmobile blue which is correct. It seems like Dupli-color has the closest match I've found. It doesn't look perfect going on but it seems to dry very close to the original.

Scott

 

Hey everyone, its been a while and thought I'd check in with my progress. Life got in the way for a couple of months so I went dormant for a bit.

I have a new thread up devoted strictly to the crack I found in the block along where the timing cover mounts to the front of the block. Never seen anything like that and can't even fathom how it could happen.

Sad part is I have my parts painted and was getting ready to try and install everything and see if she ran or not. I have been cleaning up and painting anything I took off as it at least freshens up the top end of the motor from how things were.

I lowered and cleaned out my gas tank and found a NOS exact matching fuel pump for the in tank section and replaced the other one upstream as well.

I ended up needing a new radiator, harmonic balancer (I could tell the rubber had shifted and was bulging in spots), PS pump/pulley (pulley mushroomed as I pulled it off and couldn't find a new one until September as they were gone everywhere) water pump, and all new gaskets/hoses up front. I got new seals/fuel injectors (found new ones cheap on closeout so I will give them a try).

I also managed to get the air injector tubes off in one piece and clean them out completely. Flare nut wrenches help tremendously when breaking line nuts like that that are rusty and just asking to round over.

This business with the crack up front is a colossal buzz kill. On one hand I could easily pull the motor/trans because there is almost nothing hooked up to the block as it stands. On the other hand this has already gotten so much more out of hand than I ever wanted in terms of all the broken parts, and I was never setting out to do a restoration or anything on a car with this few miles.

Looking to see what others have to say in terms of how to proceed in terms of how bad the situation with my engine block crack is.

 

I know you’re dealing with other issues, but if you still have the gas tank out, it might be worth your while to exchange the fuel pump for one off of a TPI car from the mid/late 80s. That would eliminate the need for the horrendous external pump. I’d throw an extra set of clamps on a new set of Gates Greenshield high pressure hoses and get a Bosch cube relay to power it out of the ECU.

 

I actually put the tank back in the car and then did the upstream fuel pump while I was under there. I worked from back to front in terms of replacing/cleaning everything in the fuel system. I thought about fussing with it and putting in something better, but part of me didn't want to enter any new variables into the equation in that I put in the exact fuel pump/sending unit that was in there so it should in theory work. If things don't, then at least I am not trying to figure out if it was something I did wrong in changing the original set-up.