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Hello all

I've watched this forum for about a year and became a member this past April. Your posts have been a wealth of information as I've tried to make my 1947 Torpedo a dependable driver. I got it in 2007 and it has been an adventure. I've attached a few before and after pics. Since I got it running in 2009 (Yes, it took me two years to get it going :) I've had issues with coolant getting into the oil system. I replaced the head gasket and tried a few other remedies, but no change to the problem. I finally bit the bullet this past April and pulled the engine. I stripped it to the block and took it to a local machine shop. Turns out the #3 cylinder had corroded through to the water jacket. He sleeved and bored it. I've got it back together now and have gotten it running. My issue now is trying to get a smooth idle. I've re-gapped the points, played with the timing both advance and retard, checked spark at each plug, cleaned and reassembled the carb, but just can't get it to smoothly idle. I'm not sure what RPM I can get it to, but I know it's not 450. What am I missing?

 

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Is the automatic choke functioning normally, and you are waiting until the choke butterfly is completely open prior to attempting to adjust the idle?

 

Also, rough idle or higher than normal idle is often a function of a vacuum leak.

 

Jon.

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Thanks for the suggestions carbking. The choke is working well. I have been waiting for the valve to fully open before tinkering with all the things I talked about, including the idle adjust screw. A funny thing (demonstrating my ignorance :) ) when I fist got the car. I was looking all around the inside of the car for the choke lever. I had no idea they already had automatic chokes in 1947. One of the many things I've been learning along the way. I trace the vacuum tubes next to see if there is a possibility of a leak. I put a plug (for now) on the line that leads to the wipers. The others go to the places they are supposed to: the distributor and the vacuum assist pump. But I'll double check them to see. Thanks!

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Thanks Kornkurt, I'll give it a try. It also occurred to me that it may be leaking at the manifold. I installed new gaskets when I attached the intake and exhaust manifolds, but I'm guessing that is a possibility. I imagine I'd want to try the starter fluid at the manifold before the exhaust got very hot.

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Did you have the intake/exhaust manifolds apart ?..... If you did, you need to keep those 4 bolts (2 long,2 short) loose until stud nuts on block are tight... They can cause  a slight misalignment on the two, therefore not allowing the intake/exhaust gasket to seal proper on the block. Ask me how I know..!! John

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Thanks John. If I have time today I'm going to pull the manifolds off. When I first got it running a week ago, it sounded like more exhaust noise around the engine than I remembered. I thought it was the manifold to exhaust pipe not sealing completely. Now my guess is that the manifold to block was not sealing causing the extra exhaust sound, and concurrently not properly sealing the intakes. When I reassemble I'll be sure to torque up the manifolds to block first.

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when bolting up the straight eight or six manifolds to the block, have the four bolts joining the two manifolds together loose, and use the gasket made to seal up the heat riser, tighten the manifold to block nuts and thick washers starting from the center and alternate from front half to back half working your way out to both ends, then after the manifolds are tight to the block, tighten up the four bolts for the heat riser.

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If you have not had the bolts holding the two manifolds loos, DON"T.  Leave them alone as they will probably twist off and then you will be in DEEP do-do.  Just take them to a machine shop like I suggested and let them work their magic.  Then when they are nice and straight, you will be able to get them to seal.  I have done this many times with many cars. If you need another gasket set, give me a call 641-648-9086.  Good luck!!

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Success!!! I pulled the manifolds and found that the bottom edge of the exhaust manifold got caught on the top lip of the valve cover. So I had the width of the sheet metal valve cover leaving a gap at the bottom of the manifolds. That explains both the extra exhaust noise and the rough idle. After bending the valve cover lip out of the way and reinstalling the manifolds (and carburetor, fuel line, vacuum lines, throttle linkage....etc) it started up and purred like a kitten. Smooth as butter. For the time being I've adjusted the timing by ear, advancing it until it started to get a little rough, then retarding just a touch. Not very scientific, but I don't have a timing light right now. Now it is time to wrestle with the hood and try to get it lined up and springs attached. Ugh :(

One thing I did find out the hard way (like I learn most things) is that the studs go through to the water jacket. When I pulled the manifolds in April, one of the nuts was welded to the stud, probably from the heat of the exhaust manifold and 70 years of inattention. So the stud came out when I turned the nut. At the time it was not an issue, since all the fluids were drained in preparation for pulling the engine. When I put the manifolds back on two weeks ago I just used that nut/stud as if it were a bolt, not having a replacement stud on hand. Then when removing the manifolds again last week (after all the fluids were filled) I removed the nut/stud combination and got a steady stream of coolant. Live and learn. This time I ordered a replacement stud and used that when reassembling the manifolds.

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