A few months back I had several discussions about doing a timing chain and lifters on my 73 eldorado. I dropped the engine and transmission back in the car and was in the process of tightening an exhaust nut when the stud broke. It was in fairly good condition from what I could tell, so I didn't bother with trying to get it out. That being said, I decided to pull the manifold. I borrowed an acetylene torch and managed to get 7 out of 8 exhaust bolts out. I tried everything I could think of buy I still have a broken bolt in the head. So here I am, pulling the head back off my engine. Has anyone else had this kind of luck? It's convertible season and mine is sitting....
"Has anyone else had this kind of luck?"
;D Probably most everyone here that works on their older cars --- or pays someone else to do it.
Welcome to the very large club, you have now paid your lifetime membership dues in full.
If you have a torch and you have a feeling the bolt will break just cut the head off the bolt and remove the manifold leaving the stud in the head. With the manifold out of the way you can then get the torch right at the threads and you will then have a 98% chance of getting it out.
It really stinks when you break the bolt off so there is nothing sticking out. It can take a couple hours to get a broken bolt out if its broke off flush, and that is with the head sitting on the bench, not in the car.
I was really hopeful about getting the bolt out with the head in the car since it threads into an "ear" rather than into a solid piece of metal. The downside is the bolts are facing at a downward angle, so you basically poking around in the dark.
I've had bad luck with my old cars, but I can't seem to break the cycle on this one....
If its one of the ear ones usually you can heat em pretty easily and then work it out assuming you still have something to grab onto. I have been amazed at what you can do with some real heat.
Don't forget the "magic" 50-50 ATF and acetone penetrating oil. ALL the exhaust manifold bolts I used this on came out with no heat, including one that had been broken off by a mechanic years ago. Remember it's flammable and it eats paint. I did use this in combination with a torch on a body mount bolt; the small amount there flared up for an instant then was gone. Yes, I had a fire extinguisher at my side.
For what it's worth, I had some work done on Bessie around 12 years ago when she was my daily driver. The mechanic broke the back TWO bolts on the right side manifold and then left them that way. The surprise was that he also stuck a gasket behind the manifold and there was no noticeable leak. In fact the exhaust was quieter than before. So, depending on how much it would bug you, you could do the same and figure 7 of 8 bolts is good enough. Just food for thought.
-mB
I thought about leaving that one broken, but that's where my automotive OCD kicks in. I like to have everything right. I'm not overly happy that I have to use a bolt, rather than a stud, to mount my exhaust flange to the manifold.
I'm going to have to try the acetone mix. I was told a long time ago to use brake fluid and transmission fluid, and that's what I used on my problem child bolt...but you see how I wound up....
Yes, we all have this luck. Mine has been more plentiful when my son broke three bolts on the tail section of the transmission (RWD). We needed to replace the internal O-ring that if leaks fluid exits weep hole in drive shaft.
However when the stud on my exhaust manifold broke luck was on my side. I was able to get at it (RWD) with left handed drill bits and removed it in a half hour without removing exhaust manifold from engine.
This happens to everyone. Use that 50/50 mixture, that is how I got the other three studs out with minimal trouble.
If I had 5 bucks for every broken bolt I've drilled out.........especially manifolds.
D schroeder
Okay guys, I finally had some time yesterday to put my Eldo back together. When I started it, I found that the car is now running rougher than ever.
While I had the engine apart to have the bolt drilled, I found the reason for the tick it had developed. One of my brand new lifters had broken. There was a big chunk of metal missing. Luckily I found most of it. I put a new lifter in and proceeded to put everything back together.
I notice the rocker arms on cylinder #6 were a little loose. When I started the car the ticking was terrible. On top of that, the car shakes terribly at any rpm. I'm at a loss. Do I need to replace the rocker arms?
Sometimes shutting the engine off and restarting a few times will allow the lifter to pump up and then all may be fine. Firing order correct on wires?
D schroeder
Can you give us a quick recap of the history of this car / motor? How long you have had it and what you have done to it since you got it?
Sure thing. I bought the car last year in September. The odometer reads 15k, so I will assume 115k. Since I've had the car, I've replaced the timing chain, cam shaft, and all 16 lifters....well 17 if you count the one I found broken. The engine seems to be in relatively good condition overall though.
If the intake manifold is not sealed all the way around (especially good in corners), not just the 8 intake ports, it will run poorly. This is due to major vacuum leak, timing will pulse giving the impression of warn distributor bearings.
I just replaced the lifters on my 1970 RWD 472 engine, and since the engine was apart I did the rods too, and had to replace two arms. However, had good luck. The timing was way off though after finihsing, had to major re-set.
Where did you get the rocker arm? The new ones are crap to be nice, best is good used. That is what I did.
Rough running does not usually have too much to do with all this, sounds more like firing order wrong as posted earlier.
The first time I sealed my intake, I didn't use enough permatex and I had oil spewing out of the back of my engine during break in. The next two times I did it, I used an entire tube just to be sure it wasn't going to leak. I put some around the intake ports as well even though this is a dry manifold.
I haven't replaced any rocker arms as of yet. I know of a '72 eldorado in a salvage yard that looks to have a decent engine in it, so I'm thinking about going to pull a set of arms and t-brackets off of it.
For some reason I can't get off the idea that the rocker arm is so loose that it's not open my valves all the way.
I'm going to double check my plug wires...I just put them on yesterday. When I took the head off, I ripped three out of four of the d*mn things...
I Havnt worked on the 390 in many years...are the pushrods the same on each end? In other words, is the tip smaller on one end then the other? I made the mistake of getting one upside down on a ford once. Drove me almost into a straight jacket till I figured it out. Same symptom....noisy lifter.
D schroeder
Well this is a 500, but no I haven't heard anything about the rods being one way. They look the same. When I tear it apart again, I'll look a little closer.
If the rocker arms are loose, something isn't right. Either the pushrods are bent, the valves are bent/stuck open or the cam lobes are flat. Since you say you replaced all the valve train parts I'm assuming those are ok. That just leaves the valves. I would pull the rocker shaft off and check the valves. You can lay a straight edge across the top of all the valves to see if they are all the same height. You can also tap them with a hammer and you should feel them open and them hear them snap shut. Just make sure the cylinder you are checking isn't at TDC when you do this. FYI....anytime I am planning to open a motor up I do a compression test first....then if you get a low reading you can address the problem while it's apart instead of having to tear it down again. Another point, since you have a new cam and lifters you need to do a cam break in. So don't run it any more than you have to until you can find the problem or you will end up with a flat cam.
Last night I pulled the valve cover off again. It seemed like the valve was opening as much as the rest of them. I pulled the push rods and it wasn't vent. The arm seemed fine too. I'm going to pull it back down tonight run a straight edge across the valves.
Something else I was going to post was now the car doesn't want to idle. I'm not sure if the timing got knocked out or my carb needs adjustment. Either way, it's beginning to get frustrating. Instead of driving my convertible on Sundays, I'm working on it
I would like to have someone who is wiser than myself in the ways of the cadillac look at this car. Maybe not so much to work on it, but to listen to it and give me instructions. However, no one where I live wants to mess with it.
If those rocker arms are loose then it's only running on 7 cylinders.....that's why it's not idling or running well.
What part of the world are you in? Maybe there is someone on this board that is not too far away that would be willing to come over and offer their opinion in person.
QuoteEither way, it's beginning to get frustrating. Instead of driving my convertible on Sundays, I'm working on it
Hey man, you have a convertible! And yes, the old girls can get cantankerous from time to time! My '57 is currently throwing a meltdown because I drive the heck out of it and whereas today I would be happy to drive it around, I am about to pull one of the exhaust manifolds to track down a noise and then change the plug wires to eliminate a possible fault. On the up side, you are spending time with your car and learning things about how it works, which can be of great help in the future. These cars aren't like my trusty Saturn, which is a great "jump in and go" car (it is a '95 and due for a complete engine teardown). So you may not be able to do what you want at the moment, but there is a very positive side to it all! Welcome to the club - now I need to go and remove that #$^%)*#$ manifold!
Dave Burke
Quote from: TJ Hopland on July 08, 2014, 11:12:36 AM
What part of the world are you in? Maybe there is someone on this board that is not too far away that would be willing to come over and offer their opinion in person.
I'm in central Texas. I'm off of interstate 10 right between San Antonio and Houston.
David,
Thanks for the words of encouragement. The wealth of information you guys on this forum provide us invaluable. I'm glad to see that I'm not the only one fighting with an exhaust manifold :). I love spending time with my car...I just want to be behind the wheel.
That's not to far from me. I'm on the SW side of Houston.
I took my rocker arms off.....again. I took a straight edge and put it on top of the valves. I can't see any noticeable differences in the heights. I took a hammer and tapped all eight of them on that head. They all snapped shut.
I took the rocker arms and the retainer and swapped them. I torqued the the bolts and I found that the same rocker arm that was loose on #6 is also loose when it gets moved to #2. Since I'll be within a short distance of a salvage yard tomorrow, I'm going to stop by and get me another set or two and hope they work...