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Full Version: Motor twisting on mounts and running poorly
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Finally spring and warm weather are here in Seattle so I just uncovered the 72 coronet today to take it out on a quick drive around. It fired up no problem and it purred after warming up a bit. I drove it about 3 miles without problem then I went over some railroad tracks which shook the car up a bit but not terrible. After the tracks the car suddenly started having trouble idling. It died on me at a few lights but I was able to get home. I at first I thought maybe bad fuel from sitting so I filled it up with 92 octane(about 9 gallons). When I got it home I opened up the hood and noticed the engine had twisted toward the passenger side about 5-10 degrees or so. I lifted the front of the car and took a look at the motor mounts. The metal looked intact just the bushing was compressed on the passenger side as well as the transmission mount looking all twisted. I started the car up and put it in reverse which slowly twisted the engine back to center where it stopped. Now I can barely keep the engine running at idle. It will run rough with the RPMs up which makes me think possibly a vacuum leak was created when the engine twisted but I've checked all vacuum hoses I can see.

Questions are:
What the hell is causing the engine to twist?
What should I check on the engine that may be causing it to die at idle.
This doesn't sound good. Can you get a trusted friend to watch and see if you can twist the engine back up a little? Make sure you or your friend is watching everything carefully. Sounds like something is moving that is not supposed to.
The engine is twisted back up center.
Quote:I started the car up and put it in reverse which slowly twisted the engine back to center where it stopped.
tkarman Wrote:Questions are:
What the hell is causing the engine to twist?

Most likely both motor mounts are broken. I've seen this happen on a 73 Charger, both mounts broke and the engine flops around in the engine compartment like a fish out of water..


What should I check on the engine that may be causing it to die at idle.[/QUOTE]

If the car has power brakes, make sure the hose is still connected. Also, with the engine moving around, it may have caught a plug wire or 2 on something, and then it disconnected from the plug when it moves some more. Saw both on that Charger.
I agree with Mike, you most likely have bad motor and transmission mounts.

Regarding the engine not idling properly, you might have knocked either the throttle linkage, or the transmission kick down linkage out of adjustment when the motor and transmission moved on the broken mounts, so after you check out and possibly replace the motor and transmission mounts, recheck the throttle linkage and kick down linkage adjustment.

Richard
I would put a steel mount on one side and a regular on the other.
Racer Brown Wrote:I would put a steel mount on one side and a regular on the other.

Depending on the motor that's in the car, I think a solid mount would be extreme overkill.

I good set of stock quality motor mounts will most likely outlive the car. For extra protection, there are the locking mounts available from Mancini and Schumacher (they are quite pricey however).

Another alternative for extra protection is to use the stock mounts, and then use a torque strap from Mancini's, or the old school method of connecting a chain to the motor mount and then to the K-frame.
Thank you for all the responses! FYI the engine is a 318. It must be a broken mount on the drivers side as the engine flops back to center when in reverse and not all the way to the other side. Either way I'm going to replace them both. I'm moving right now and have no time to work on it so I got a quote for $280 to replace both at a local shop that was recommended. This seems like a normal for labor and parts for something like this. I know it's really easy but I honestly have no time at all. I'm going to go out and check the engine one last time to see if I can find out why it's running poorly before I take it down there. I don't think it is the kick down or throttle linkage because along with it not idling it also is running rough at higher RPMs. I has to be vacuum or electrical...and hopefully not something more serious.

If I can't solve the idle problem is there a way to keep the idle up on this carb. I've already screwed what looks like the idle screw in all the way. This is the screw that attaches to the throttle linkage that bumps into the butterfly valve control on the carb. I also see what looks like a mixture screw near the base front of the carb. Not sure if messing with this will help up the RPMs at idle or not?
Not sure what is going on but the car was running fine when I started it up today. Before starting I did go over every electrical connection in the engine bay and just wiggled it and made sure it was plugged in all the way. I didn't find anything suspicious but who knows. Maybe corrosion and a little jostle by the engine cause the issue. It is now at the shop until Wednesday and I should know more then.
Oh, I thought you we're doing a BB!
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