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Jim, for finding TDC what I've been doing is pulling the valve cover (so I can see the rocker's positon) and removing the spark plugs. I put the car in 4th, and just pull 'er forward until I am at TDC. It's just one more advantage with these little cars, light and easily moved with 1 hand!
 
Have you triple checked the order of the plug wires?
 
Atrus said:
Jim, for finding TDC what I've been doing is pulling the valve cover (so I can see the rocker's positon) and removing the spark plugs. I put the car in 4th, and just pull 'er forward until I am at TDC. It's just one more advantage with these little cars, light and easily moved with 1 hand!
Click to expand...

/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif MUCH easier than undoing mounts etc.! One hand bumping a front wheel will move things quite easily!! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
Unbolting the engine mounts was easier for me since I didn't have a lot of room (or energy) to push the car around. With the bolt accessible TDC was a much easier and less frustrating adventure.

Tried plug wires in a different sequence, but she wouldn't even think about firing up. I have to have full choke on to have her run. For some reason the choke mechanisms on these SUs are very difficult to move, and my cable won't budge them. Cable moves freely if I disconnect it.

If I press the gas pedal she'll rev up and smooth out with an occasional pop or backfire through the carbs. Since the tach is dead I don't know what RPM I'm going to. Take my foot off to try to hop out so I can press the choke mechanism down and she dies.
 
Jim, it sounds as though it's time for some serious carburetor work. Have you checked to make sure the jets move freely in the bearings?
Jeff
 
The pistons move up and down freely if that's what you mean. I bought these carbs from someone already rebuilt. Throttle mechanism moves freely with no resistance. There's a lot of resistance on the choke mechanisms. It's difficult to move up and down by hand. I've got the SU book out now looking it over trying to figure out where to go next. I figure I'll be spending time on the carb side today.
 
Jim, I mean the jets. The jet assembly plugs into the bottom of the carb. With the linkage disconnected the jet should slide freely up and down. I've heard that some of the currently available jets may bind in the jet bearing.
Jeff
 
jhorton3 said:
Tried plug wires in a different sequence, but she wouldn't even think about firing up. I have to have full choke on to have her run. For some reason the choke mechanisms on these SUs are very difficult to move, and my cable won't budge them. Cable moves freely if I disconnect it.
Click to expand...

Jim, there's an entire thread on fixing the sticky choke; I'm heading out to the garage, but perhaps someone will post a link, or you could try the search feature for "sticking choke cable" or something similar.

-Duncan, Ottawa
78 Midget 1500
 
Have I not seen a tip on Tonys site??
 
I loosened up the choke linkage on the right carb, and that allowed both to move a easier. Noticed that the choke cable isn't moving the linkage all the way to full choke on. Choke cable is moving a little easier. I can at least push in and have the choke push off.

The engine sounds...odd. Sounds more like a lawn mower engine at the moment. Started it up and it runs a higher RPM. Tach still dead, but I'd estimate a little over 2500 RPM. I can step on the gas pedal and she revs higher. Push the choke cable in and RPMs start droping quickly. Choke off and she starts loping around what sounds like under 700 RPM, then dies.
 
Air leak?
 
So far I found that the hose I put between the timing cover oil catch can and intake manifold port had slipped off the manifold side. I didn't just have an air leak, but an air flood! When I had the car running with the choke on I pushed the pipe up to the port and the engine started to smooth out a little. I still have work to do, as it still died when I released the choke.

I also decided to investigate why my tach wasn't working. Pulled the dash off and took a look. White/black wire connected...check. Green wire connected...check. White wire...where's the white wire? I looked and I cannot find a white wire connection anywhere on the harness. I made up a test wire connected on the white wire side of the coil, and the other to the tach. Cranked the engine and tach is alive.

Should the white wire connection be part of the main harness or the dash harness? If it doesn't exist I'll get a white wire, route it along with the harness and go from there. It does bother me that I can't find it.
 
white wire should be in the dizzy harness,,,,


mark
 
Jim, there shouldn't be a white wire connection to the tach. The white / black finds its way to the negative coil terminal, and the green wire eventually winds up at the fuse block.
The only other wiring back there should be for the light. I'll try to get a look under the dash of my '74 tomorrow.
Jeff
 
Disconnect the timing cover hose from the manifold and plug the manifold fitting with a vacuum plug. just use the timing cover hose as a crankcase vent!
 
Here's the latest on the Midgie saga. I thought I was going to be very clever and show my wife what I'd been doing all weekend when she came home. I flipped on the light switch, which she was shocked the lights came on at all. Then I bumped the ignition switch and she fired up. Her eyes really lit up. I thought she was excited to see it run. She was, but she wasn't expecting the huge smokescreen she was producing. When I looked around I couldn't even see the driveway it was so thick. I immediately shut it down. She's still impressed I got it to start and run for a little while though.

Today I started tinkering with the car again. Still running like crap no matter what I did. Then the smokescreen came back to life. It wasn't exactly blueish smoke, but more white. I thought "oh crap, now I've got a coolant leak somewhere." I'd shut off for 5-10 minutes, fire her up and the cloud appeared again and again. Great for killing mosquitoes, but not this time of year. I was really getting discouraged thinking all my efforts were going to have to be torn down again to source this problem.

As I was fooling around the hose to the timing cover oil catch can popped off. Then I remembered the last post about plugging this hose. The quickest thing I could get my hands on was a tail light bulb laying on the shelf. I stuffed that in the hose and fired her up again. A little cloud, and then it went away. The best part is, the idle smoothed out and she's running like a top!

I've got a few more adjustments to make here and there with the carbs and timing, but for right now I'm very happy at what's been accomplished! Next task at hand will be figuring out how to bleed the clutch system. New slave, master cylinder, pipe, and hose. The fun just never stops!
 
Shouldn't that hose go to a valve or something first before directly into the carbs? (Gulp valve?)

Most American cars will use a PCV valve in the crankcase breathing system between the crankcase and inlet manifold.

I know the Midget hose it isn't going directly to manifold vacuum, but even carburetor vacuum is rather strong and is certainly pulling oil directly up. This assumption is based on the smoke stopping when it was plugged.
 
Yes- it sounds like a PCV valve that should have been in the line is missing. A proper BMC PCV valve is expensive if you don't already have one but just about any generic PCV valve with 1/2" inlet and outlet will work fine. I use one from a Datsun 210 since that is what was lying around when I needed one.
Bill
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif Exactly why I said unplug the timing cover hose and use it as a crankcase vent and plug the manifold! The car should run 100% better now and without smoke! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
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