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MG MGA - Hit my first snag - no spark

Hi,

Okay, I've never really messed with this stuff, so maybe I did something wrong. I hooked up my A to a new battery. It was a little exciting to see that at least something works (the lights).

http://img294.imageshack.us/img294/6343/dec25lightsxs5.jpg

But I turned the key, pulled the starter cable from under the hood (it's rusted from inside), the starter tried to start it, but when I moved the spark plug wire to the spark plug, no spark.

I've replaced the points and condenser. I didn't put a washer under the new condenser because it kept falling off, but that shouldn't matter as this just hold it in place. (I've circled this yellow). On the points I screwed down the eyelet that went to the distributor, then on top of that the one that went to the condenser and then the plastic washer on top of that. (I've circled this blue.) I wasn't able to find an adapter for the new sports coil I installed, so I just shoved the wire into it as a temporary measure to test it.

http://img245.imageshack.us/img245/1029/condmi3.jpg

http://img290.imageshack.us/img290/3788/coilcy1.jpg

By the way, the first time I used the starter, it started trying to turn over the engine. After that, it just made a slight sound. Did I just break the starter?

I've heard about Lucas being the Prince of Darkness. This is pretty frustrating.
Darian Henderson

Darien, having sat that long, you will probably find a lot of "stuff" that is the result of rust, corrosion, etc. The first thing I would do before I tried to start the engine is to change the oil and the oil filter. Then I would check the ground from the engine to the frame- it is a braided cable from down under the distributor side to the frame. If the lights went on, I suspect that the battery ground is probably ok. Do you have an ohmmeter to measure electrical resistance with??
Have you checked the compression yet?
/ gil
gil

Haven't checked the compression as I was hoping to just mess with the electrical stuff for now. I suppose I should invest in an ohmmeter.
Darian Henderson

Don't forget postive ground!!
Tom

Check that you put the wire on the points correctly. Many do not put the wire on first then the plastic insulator so it does not ground out. Look in the archive for more information on this.
JEFF BECKER

Before we all conspire to reinvent the wheel, read this on ignition troubleshooting: http://mgaguru.com/mgtech/ignition/ig106.htm
Barney Gaylord

Yes, Darian, a multimeter will turn into one of your best friends. Doesn't have to be big, fancy or expensive.

http://cgi.ebay.com/ebaymotors/MULTIMETER-POCKET-SIZE-PROBE-STORAGE-AUDIBLE-CONT-NR_W0QQitemZ220064249564QQihZ012QQcategoryZ43989QQrdZ1QQcmdZViewItem

Nice and compact. Easy to carry in a traveling toolkit. A few jumper wires with alligator clips at each end should be in there too. With a roll of electrical tape. And a photocopy of the wiring diagram.

While your exploring and poking around, I'd suggest that you keep a can of PB Blaster handy and give a little shot of it to each and every fastener that you come across as you do the rounds. Might as well start getting them ready to be undone (eventually). A shot into each and every Lucar (bullet) electrical connector, then disconnect, clean and reconnect with a bit of di-electric grease will help clear up many Lucas gremlins, too.

More reading inbound.

TTFN

Derek Nicholson

Thanks again everyone. And I got the manuals, Derek. I really appreciate it.
Darian Henderson

Hi Darian
Do not give up! Get the engine turn over,spinnig. Your starter switch looks bad. Clean around sparkplug and get them out,try again-engine spins?great, no spin,use jump cable to starter,from your day driver, spins? no/ Yes.If no, use jump cable to sterter switch(under hood)use your hand to pull switch to engage. From there there is more to look at then I can tell you here. In any case You should run the engine using starter only for oil to get the oil going around.
DISCONECT THE fuel pump
Good luck
Marry exmas
Martin
Martin

If it hasn't run in some time, in addition to the other advice, it is a good idea to get all the old gas out of the fuel system and replace with fresh. To empty the tank on my '59, I disconnected the flex hose from the hard line at the firewall, and ran another hose into a gas can. I hooked up jumper cables to my Jeep (MG battery was long dead) and ran the fuel pump. Had to use BMC Special Tool #1 to make the fuel pump run though...
Del Rawlins

I don't get it. I've described the sound that the starter made. Now I can't get the engine to move at all. I don't have the hand crank, so I grabbed a wrench and put it on that bolt the hand crank goes into and it moved a tiny bit when I turned it clockwise and then stopped. Now when I turn it, the whole engine starts to move. I tried removing the spark plugs, thinking that would relieve the compression, but still no luck.

Is this because the engine is dry, could something else be going on? I sprayed WD-40 into the holes where the spark plugs were, haven't noticed anything yet. The carbs are off, though that shouldn't matter. I just wanted to see if the engine was seized. The mechanic before said it turned when he tried to start it, so this is really weird.

Given up on the spark for the time being until I get the books.
Darian Henderson

Too bad you can't edit these messages. What I meant to say is that I've given up for the time being on the spark until I have a chance to talk to someone locally and look at the books.
Darian Henderson

If there is any doubt about the engine being free, since you have the spark plugs out, put it in gear and try to push the car back and forth. It should be obvious whether it will turn or not. But it sounds as though it was at least turning over when you began, so seizing it up without actually starting it seems unlikely.

Actually, now that I think about it, was the transmission in neutral when you tried turning it over with the crank? If it was in gear, depending on which gear it was in, you wouldn't be able to turn it easily. Especially if the brake is set and/or frozen.

Once you establish that the engine is free, I would briefly apply voltage to the starter switch terminal where the cable to the starter is connected (connect the ground to the engine). If it still doesn't crank, bypass the cable and supply voltage to the starter terminal itself. You should be able to isolate the problem in this manner. You'll have to determine correct polarity for yourself, as I have no way of knowing if your car has been previously converted to negative ground.

I will also second the advice to change the oil and filter right away. Oil is cheap. You are on the right track about oil through the spark plug holes, but I wouldn't use WD-40, since it really isn't that great of a lubricant. A small amount of new engine oil will probably work as well as anything.
Del Rawlins

Darian, - It sounds like you said the engine did first turn over with the starter, then you were checking for spark, then the engine did not turn. When you put a wrench on the crahk nut it dd not turn. Posssibly the stater pinion is stuck in the ring gear. Put it in 4th gear and roll the car backward to turn the engine backward to free the starter pinion.

Then you can roll the car forward to verify that the engine will turn forward (clockwise from the front). Nothing is going to work if the engine will not rotate.

If/when you get the engine to turn freely, if the starter cranks it very slow or not at all check here:
http://mgaguru.com/mgtech/electric/ss_101.htm
http://mgaguru.com/mgtech/electric/ss_102.htm

From your original post and picture condmi3.jpg, the picture is blurry so hard to see details. The screw holding the condenser must be tight, as the condenser must be grounded to work. Where the spring arm for the contact points attaches to the screw post, the spring arm must be electrically isolated from the screw post with a pair of nylon grommets, and the two wires must both be electrically connected to the spring arm, not touching the nut.
Barney Gaylord

Darian,
Another check is to verify that none of the valves are seized open. I know nothing about cross flow heads, but it may be possible for the valve hit the piston head and keep the engine locked up. You will have to pull the valve cover for this, but I think that it is worth the time. Check all the valves as you try to rotate the crankshaft. Good luck.
mike parker

Darian will probably have to ask this question at some point, so I'll ask it now so that he has the answer when it's needed. besides, I'm curious. What valves would he have to buy to replace any damaged ones? Standard 'A? 'B? What sizes (dia.) were fitted typically, assuming that he has a Derrington head? And what about head, intake & exhaust gaskets? Standard 'B series?

Heater? Don't need no stinkin' heater in Texas!

Derek Nicholson

What the heck. Might as well ask if the valve springs are anything special at the same time. And valve clearances? Different from standard "B" Series?

Derek Nicholson

Del, if you were in Texas I'd buy you a beer! I hope you haven't lost respect for me, but the kind was in gear. Kind of hard to turn the engine over when it's in gear with the parking break on. I feel pretty stupid, but it's the kind of mistake you make only once and that's how you learn.

The starter works and the engine spins, though sometimes when I pulled the starter it didn't work. I had to do it about five times, though, just because watching that thing spin put such a grin on my face. I was pretty depressed to think that the engine was seized.

Yeah, heater is not my top priority, but I think that Barney had a very good idea with the heater and eventually I will do exactly what he said.

Still no spark, but I will have someone help me with it this weekend.

Thanks for the help. I can sleep well tonight.
Darian Henderson

On the first line it should say, "but the car was in gear," not "kind."
Darian Henderson

Don't feel bad. At least you didn't try to start your car using the hand crank with it left in gear, parking brake off. Not that anybody I know would try to do anything that stupid.... I think one would have to move pretty fast to get out of the way, and get it shut off. Especially with the top up and side curtains on. At least, I imagine so.
Del Rawlins

And then collect your thoughts and do it all over again, but this time out of gear...
Tom

It would not have been so bad, except my dad was watching the whole fiasco.
Del Rawlins

And probably rolling on the ground too, no doubt!
mike parker

This thread was discussed between 25/12/2006 and 30/12/2006

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