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1987 Brougham
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Discussion Starter #1
Hi everyone! I don’t know if you have been keeping up on the threads in this category, but I finally got my 1968 coupe Deville started for the first time in probably 10 years (since the last owner had it). I just got it started yesterday running on an external gas tank and it ran for five or so minutes sounding wonderful and running like a top!

It’s time To do some system checks. I know that there is no coolant in the engine, I’m pretty sure there’s no brake fluid, I’m going to give it an oil change, and I know that the system is in charging so I’m going to change the alternator and regulator.

Are there any special fluids that need to go into the car besides those that I will buy over the counter? For example, can the coolant that I add to the system just be the green type coolant or should it be Dexcool for GM vehicles? In this example, I know Dexcool came out way after this car was produced, but I’m just asking what anybody has an opinion on or what runs best in the vehicle for coolant, brake fluid, things like that. Thank you so much in advance!

-D.C.
 

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96 FWB
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752 Posts
If you have the owner's manual, then I recommend reading it cover to cover. If not in possession then strongly recommend getting one. There is little reason to change from the car's oem specs for AF and brake fluid; IAT coolant (green) and regular DOT3 brake fluid. Many oils today are either blended or full synthetic as well as those without such designation. Just make certain you use the car's specified classifications. The major exception is transmission fluid, where you would do well to search, "pros and cons full flush transmission fluid". If you decide in favor of full flush then remove all DEX III entirely and replace with DEX VI. If not doing the simple procedure yourself and choosing to have a shop do it, then recommend NOT going to one that uses a power flush machine.
 

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1987 Brougham
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114 Posts
Discussion Starter #3
Thank you very much for the information. That’s a lot of what I needed to know. I plan on checking all the fluids and eventually, doing a tranny service on the car, but I have to see if it runs well and drives first.

Seeing as how the car hasn’t been used in (let’s say...) five years, I’m worried about the fuel tank and the car running off it (right now have an aux tank on the car). Aside from dropping the tank and cleaning it out fully, any methods for refreshing the fuel/ tank as it is? I give gas a, roughly, six year life so it’s right there, and I’ve only dealt with this situation once before a long time ago. Any fluids to recommend besides just filling it up with good gas and seeing what happens??? Thanks!!!

-D.C.
 

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96 FWB
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752 Posts
.....
.....any methods for refreshing the fuel/ tank as it is? ........Any fluids to recommend besides just filling it up with good gas and seeing what happens??? Thanks!!!

-D.C.
Sorry, no. The "do something blind and expect I'll be the lucky guy who gets the miracle from above GO FREE PASS in my whole city" that day approach is not my style.

Drop the tank. You'll see and learn more about the whole rear of the car in that one exercise than any 5 other things you can do. It's not difficult at all. Drain as much gas as possible, remove front of hangars and possibly able to move forward to remove with filler neck attached (not positive of details of your gen). You'll get great opportunity to eyeball and adjust, replace, repair:
-rear suspension - shocks, coils, inspect upper and lower control arms & bushings
-axle - replace diff. fluid, grease if any u-joint zirks
-fuel delivery - emissions/EVAP/vent hosing, connections. Most important, treat your car and yourself to a new fuel pump and harness
-brakes - it's in the air, replace everything up to and including drums and slave cyls. and all hardware
-body/frame - sacked out body mounts, any potential body rust-thru
-exhaust - everything

The ONLY thing goes in my tank besides fuel is Techron once/twice per year.

Sorry. You could be in for $200-450, but you asked. And the return (for me) is the feeling of confidence running a rig that's more bullet-proof, safer and lots less repair cost in the long run, and less breakdown on the side of a dark road for me and the family.
 

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1987 Brougham
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114 Posts
Discussion Starter #5
Again thank you for all the information. I do intend to assess and replace many if not all of those items you just mentioned. I have restored my 87 from not running to somewhat of a beauty so I know what I’m in store for in that sense LOL! With this car I really just wanted to get it running and driving so then I can assess any other issues. It’s actually in pretty good shape And only has 85,000 miles on it, being a one owner car to an older couple who am I bought it from. That being said, I want to get it running and driving first and did not know if there was any way other than dropping the tank. Thank you very much for your information and I will keep everyone posted on how it is going. Thanks!
 

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70 Deville 78 Seville 92 Deville 03 Deville
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Well it is a 68 so the tank may not be pristine. Every tank I have ever dropped was clean as a whistle inside. My 78 Seville sat for a good 6-7 years and I had to drop the tank for a sending unit issue and that tank was clean as a whistle inside. My 76 GMC was also clean as new inside, then it rusted through from the outside 1month later. The only time I see nasty gas tanks is on the internet and I have no idea what happened to them.

On this 68 I would drain it/siphon it the best I could and then put fresh gas in there and run a clear fuel filter to see if it fills with rust or not. I would bet not. I would get more peace of mind by changing the trans fluid and filter before driving the car.
 

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1987 Brougham
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Discussion Starter #7
Thanks so much!! I was thinking the same thing to start! Last thing, is there a filter in the tank or just the one in line between the tank and the carb? Thanks!!!
 

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96 FWB
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..... only has 85,000 miles on it, being a one owner car to an older couple who am I bought it from. ......
Boy, that little added gem of background earlier would have saved me a ton of typing. It sounds like you snagged a nice ride.
 

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Don't forget to change the diferential fluid.
Grease the chassis steering & suspension. Sometimes there's a grease fitting on the u-joints.

Power steering never seems to be on a maintence list.
But who knows how old it is, half a century?
 

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1987 Brougham
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114 Posts
Discussion Starter #10
Lol I agree with all of that , especially the power steering fluid!! I will be sure to check all of those items as all of them are on my personal list to check anyway but I am grateful for the information!

I also checked the transmission fluid last night. I started the car up again on the external gas tank to let it run for a minute and to investigate some of the electrical issues. While I was sitting in the driver seat, checking a few things, I put the car into reverse and drive just to see if it would pop into gear and it did not. I checkEd the transmission fluid and it was very low if present at all. I only attempted to put it in gear for a second, and seeing nothing was happening quickly put it back in the park.

I’m hoping I can pick up a few quarts of synthetic tranny fluid and at least Be able to get the car into gear and investigate how the transmission is doing on a very basic level. Any thoughts on how to proceed with the transmission besides performing for fluid and filter change in the very near future? Thanks a lot!

-D.C.
 

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1987 Brougham
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114 Posts
Discussion Starter #11
For right now finishing replacing fluids. Power steering seems to really be working fine with the car is running. I had to work extra the last few days so I did not check anything else. As for the tranny, When the car is off it will not roll in park but will roll in neutral so I’m guessing something works on it but I don’t know how much. Going to top off the tranny fluid today and see again if it goes into gear.

Any other thoughts on testing the tranny without damaging anything? Thanks again!
 
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