Well i told this hissing is completely normal for a carb. It wasnt making that noise last time when i was puttimg in seafoam so thought it was abnormal.
Warm up transmission
- Thread starter Blake Sherwin
- Start date
change that switch 
change that switch
What switch?
The car has a intermittent open in the electrical circuit. All the problems are most likely the ignition switch. But it could be as simple as the run wire off the starter or Loose wire on the coil. Mechanical problems don't normally come and go. These kind of things are frustrating not easy to trace and make you want to dump the car in a hurry. Every thing you have shown can be explained wit a intermittent open. The hissing in the carburetor was most likely a small backfire putting presser into the carb. The hissing is it going out. With the engine not running there is no vacuum.
The weak link in the 68 modal was the ignition switch. Check all the connections between the distributor and the coil the coil and the switch the switch and the starter. If they are good it's the switch. Once again simple test is the jumper wire. A piece if wire long enough to go from the pos side of the battery to the Ignition side of the coil.it. Won't start but your wire in place. If it starts take the jumper off. If it dies when you do that you have a positive test of a open circuit begween the coil and the battery. If your driving it and it starts acting up put the jumper wire on . If it starts running smooth the you have a positive test of a intermittent open between the oil and the battery. As Paul said don't run the car for any length of time with the jumper in place. You will burn the points up. But as it starts on 12 volts a short deration to test to Rule out a electrical
problem is in order before you dpend money you don't need to
The weak link in the 68 modal was the ignition switch. Check all the connections between the distributor and the coil the coil and the switch the switch and the starter. If they are good it's the switch. Once again simple test is the jumper wire. A piece if wire long enough to go from the pos side of the battery to the Ignition side of the coil.it. Won't start but your wire in place. If it starts take the jumper off. If it dies when you do that you have a positive test of a open circuit begween the coil and the battery. If your driving it and it starts acting up put the jumper wire on . If it starts running smooth the you have a positive test of a intermittent open between the oil and the battery. As Paul said don't run the car for any length of time with the jumper in place. You will burn the points up. But as it starts on 12 volts a short deration to test to Rule out a electrical
problem is in order before you dpend money you don't need to
Thanks, circling back to the previous talks about OEM being expensive and the aftermarket being a pain to install:
In your opinions, am I better off dishing out for the expensive original:
http://www.2040-parts.com/nos-gm-de...68-original-eldorado-oem-new-rare-68-i785109/
Or finding a good aftermarket for less and just paying a mechanic to properly do the job?
At $465 for the part, I'm not sure if I would just be better off getting something aftermarket and having it converted
My concern is that if I spend $465 or more on an original part and if that part is prone to failure anyway I'm going to eventually end up in the same situation again.
In your opinions, am I better off dishing out for the expensive original:
http://www.2040-parts.com/nos-gm-de...68-original-eldorado-oem-new-rare-68-i785109/
Or finding a good aftermarket for less and just paying a mechanic to properly do the job?
At $465 for the part, I'm not sure if I would just be better off getting something aftermarket and having it converted
My concern is that if I spend $465 or more on an original part and if that part is prone to failure anyway I'm going to eventually end up in the same situation again.
I'll send you the one I have on the wall. but it may not be any better then the one you have. I would not pay that kind of money and go back to a original one.
go to a place like USA parts, Caddy Daddy, Fisk or one of the other people that deal in replacement parts for vintage caddys and get the one they recommend.
put first you need to know that it is the problem. there is no since in swapping parts just to hope you get the right one.
now if you look threw here you can see all I did on this one. when I sold it it was just Doing the might start problem you have. Bill put up with things your describing till he swapped the switch for a universal one and then the car ran fine. ttps://www.dropshots.com/jer57747/albums/308015/2013-04-04/11:01:45
go to a place like USA parts, Caddy Daddy, Fisk or one of the other people that deal in replacement parts for vintage caddys and get the one they recommend.
put first you need to know that it is the problem. there is no since in swapping parts just to hope you get the right one.
now if you look threw here you can see all I did on this one. when I sold it it was just Doing the might start problem you have. Bill put up with things your describing till he swapped the switch for a universal one and then the car ran fine. ttps://www.dropshots.com/jer57747/albums/308015/2013-04-04/11:01:45
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I havent had time to check any of this yet, but I did take it for its' weekly drive over this past weekend, I had less than a quarter tank of E10 left, so I diluted it with a full tank of 0% ethanol 91 octane pure gas. Its already running much better. I know this isnt going to solve all my problems, but now I can actually floor the gas without it cutting out (not that I ever do floor it, but for testing). Before if I tried that it would choke and hesitate.
Someone else on the cadillac forums had also suggested that there may be a wire harness coming from the starter that could have melted or something, so I have added that to my list of things to investigate.
I am optimistic on the gas though. I went on about a 15-20 minute drive and was able to get up to 60 without any problems. 50 used to be a challenge before.
Someone else on the cadillac forums had also suggested that there may be a wire harness coming from the starter that could have melted or something, so I have added that to my list of things to investigate.
I am optimistic on the gas though. I went on about a 15-20 minute drive and was able to get up to 60 without any problems. 50 used to be a challenge before.
As i said it starts on 12 volts directly from the starter. The in the run position on the switch it runs on the risister wire from the switch. No that high compression 472 will nor run good on any fuel under 90 octane 91 is the requirement.
good to know, had no idea 91 was actually a requirement. I'm hoping to get some free time this weekend maybe to look close at wiring, thought I would last weekend but we were too busy.
Ignition doesnt get warm after a drive it seems. Going to drive it to my dads on easter, so that will hopefully be a good distance drive to test if the issue is going to come back.
Philip Scanio
PCS Member / Super Site Supporter
Blake, Do you have a station in town that sells 0 Ethanol gas? What brand? Thanks, Philip
Yes, there is a Shell in Owasso with 0 ethanol 91 octane. I cant get 93 though
Its a good possibility that a previous owner installed one of the $12 universal ignition switches. Someone else suggested I use a cheap one to test and linked this:
https://www.ebay.com/itm/1946-1968-...203065?hash=item33e2ba76f9:g:PPUAAOSw0UdXqecP
This looks EXACTLY like what I have now, which may be a big part of the issue if this is cheap switch cant handle what going through it. Mine even has that tiny little lockbox looking key with it.
https://www.ebay.com/itm/1946-1968-...203065?hash=item33e2ba76f9:g:PPUAAOSw0UdXqecP
This looks EXACTLY like what I have now, which may be a big part of the issue if this is cheap switch cant handle what going through it. Mine even has that tiny little lockbox looking key with it.
that switch is fully capable of handling the load . but you can't have it as yours has a GM key. or at least you showed us what you said was your switch key and it was a GM key.
Peter Grave - Deceased - 1938 - 2022
PCS Member
Son you have the CHEAP CRAP switch. I know its the cheapie cause it has the double sided key. The better ones had a heavier single sided key. There is way to beat the too heavy load on the switch. You may have to do some rewiring and use a relay.
Since it's all ready aftermarket just get a good one and replace it. Some one as all ready done the cut and splice. I'm betting one of there crimped on conductors is lose. Solder all them and the problem goes away. That door key that was not cut for your doors was most likely not even for that car.
Thanks, I know the OEM part number is 1116701 D-1440A
Offhand does anyone know of any particular aftermarket switch that will swap cleanly without having to make further modifications. I would like to find something that I can install without risk of screwing it up more.
No problem if no one knows offhand. I will do some research, but if you happen to know of one it would be appreciated. Only thing I've seen so far is the $465 NOS Delco switch
Offhand does anyone know of any particular aftermarket switch that will swap cleanly without having to make further modifications. I would like to find something that I can install without risk of screwing it up more.
No problem if no one knows offhand. I will do some research, but if you happen to know of one it would be appreciated. Only thing I've seen so far is the $465 NOS Delco switch
I see what your saying. I may just have to pull it out, take some pics and compare them on the internet.
Peter Grave - Deceased - 1938 - 2022
PCS Member
Right now it would be foolish to even try to go back to the original switch. The best bet for a good aftermarket is find one made in the USA with a brand name. Replacing should be easy except for the tight quaters you have to work in. I am with Ed if you can solder (rosen core not acid core) the terminal end where the wire goes into the end that will ensure a good connection to the terminal. If you can buy or borrow an old Weller 250 watt soldering gun thats what to use . If you can't find one I'll loan you one of mine.
