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MG MGB Technical - Won't Crank-Ingition relay smptoms?

I was out driving last Sunday. Stoped at a store for bagesl. Came out about 10 minutes later and went to start the car. Turned the key to start it made one click then nothing. Checked the battery cables, clean and tight. Used a 12v light tester, juice at the battery and power at the main cable at the starter. Also power at the brown wire to the starter relay. When I turned the key to the on/run positions I could not see the ingintion light come on. The car was sitting in the parking lot in hot bright sun so I just decided to take the tow rope out, call my wife and have her pull me home. So I could work in the garage and calmly assess things.

Now today, I go out to work on it. Here is what I have found so far. When I turn the key to the ignition position, the ingnition light comes on very faintly, then over a few seconds it starts to glow brighter with a little bit of flickering. As it gets brighter the fuel pump gives a few clicks (not as loud or dramatic as usuall) The fuel gauge comes up. I also hear a faint click from under the bonnet(one click each time I turn the key to the ignition postion). Then when I turn the key to the start postion I get a louder click and then hear a rattley, hissing, buzzing sound from under the bonnet. At the same time the ignition light dims or goes out and the feul gauge begins to drop.

Of note: When I got the car home last sunday I put the battery charger on and it indicated that it was fully charged.

Could this indicate a bad ignition relay? I would appreciate any input anyone has to give. I'm sure these someone must be familar with these symptoms.
I hate to pull my hair out trying to figure this out on my own.
Thanks,
John
John F

I suggest checking the battery connections again. Remove them both and clean them with a wire brush even if they look clean.
Randy Olson
1977 MGB
1969 E-Type Jaguar
(Both with similar battery issues recently)
randy olson

Good call Randy.
After posting I went back down to the car. After thinking about my symtoms. It sure seemed to me as though these were indicative of a low battery. So I decided to jump it with my 4-Runner. Sure enough after connecting it to my running 4-Runner, now when I turn the key to on, the ignition light glows bright the fuel pump clicks with intensity and then when I turn the key to start she cranks and STARTS!!

So I unhook the jumper cables and let it run a while. No glowing of the ignition light, So I assume the alternator is putting out. So I shut it off and proceed to disconnect the battery cables. I remove the battery from the car entirely and connect it to the battery charger it still indicates it has a full charge. The battery cables and the batt terminals still looked clean but I wire brushed them anyway. I am wondering if the battery ground is at a good connection point it is grounded to the battery holder. Do you think this is the right and proper place. I remember attaching it there several years ago, but can't remember if that is the proper place for it to be. I will unbolt it and make sure it is rust and corrosion free then re-attach it.

In the mean time is there anyway to test the battery for it's conditon while I have it out of the car. Maybe I can take it down to checker or AutoZone. And have them test it under load. It is about six years old the battery. Maybe even though the charger says it is charged it just doesn't have the kick it ought to.

Sorry for all this rambling.
Thanks again.
John
John F

John - You could have a flakey ground for the battery or the ground strap on the engine could be flakey. It would be a good idea to clean and renew the ground points at both of these areas. That said, a 6 year old battery would be my first suspect. To be on the safe side, I would replace the battery. If it isn't bad right now it will be in a very short time. A 6 year old battery is sort of like a 95 year old person trying to run a marathon - quite possible, but not pretty.
Good luck - Dave
David DuBois

John. I believe that Randy and Dave are on the correct path. The symptoms you describe could have been from either a bad ignition relay or a battery problem. But, if it was a bad relay, you would have been able to turn the engine over on the starter relay (different circuit) and you would be able to turn on the head lights and sound the horn strongly. (headlights and a strong horn are an excellent quick check of the battery condition when there are problems.)

The problems you describe are often caused by battery/connections/cables.

Yes, take the battery in and have it checked out professionally. If you have to replace it, you might consider one of the new Gel type batteries. They are expensive, about three times the cost of a lead-acid battery. Indications so far are that they will last significantly longer than the lead-acid battery and will not leak on the battery compartment. My daughter's Miata currently has the Gel battery (standard on the Miata) and I will be using one on the next MGB to need a battery.

Battery terminals and insides of the cable clamps should be clean and free of corrosion. A layer of grease on the two will provide additional protection. Make sure the cable clamp fits the terminal tightly. If the cable clamps are of the type which attach to the cable by two bolts and a cross strap (aftermarket replacement for the molded on clamp), make sure the cable and clamp are clean and tightly joined. Had one of these loosen once and it was the last thing I checked after replacing the starter. Lot of work to replace a good starter with a good starter. Check the easy to get to things first.

The ground connections, the one from the negative terminal of the battery to the frame and the one from the transmission to cross member (later cars) or engine to engine mount (early cars) should be checked to make sure they are clean, in good condition and tight.

The cable from the positive terminal of the battery to the starter motor can corrode internally--sufficiently so that it will not allow the starter to work. When this happens, however, you normally get the ignition warning light and the sound of the fuel pump, just no starter. Using a volt meter to measure the voltage at the main terminal of the starter as the engine is being cranked (or as you are trying to crank it) will give you an indication of the condition of this circuit. You should have at least 11.5 volts when cranking.

Please let us know what you find to be the problem or problems. Les
Les Bengtson

John - You may also want to read my article on ground point preparation and get some of the Kopr-Shield or a similiar product to use on all of your ground points to insure a good, long lasting connection. The article is at: http://www.omgtr.ca/technical/General%20Technical/grounding.htm
Good luck - Dave
David DuBois

I just read Moss Motor's tech note that stated 50% of electrical failures are due to poor batteries. They recommend replacing the clamps on the battery poles every year!
The cable clamp on the positive pole in my car was badly deteriorated and was unable to make a solid connection. Symptoms were no fuel pump, no starting, nada.
The Moss article went on to say that the fuse box attributes to 25% of all electrical problems. They recommend cleaning the fuse holders with Brasso.
Cheers,
Randy
1977 MGB
randy olson

Thanks to Everyone,
It is running smooth agian. The battery was shot when tested under load. So a new one from SAMS CLUB did the trick. It's funny in the past with other cars, I could usually tell that the battery was going bad. i.e. sluggish turning of the starter. This time however all seemed fine....then no start. Anyway cables all look good. Cleaned them well. I did see the new gel type batteries and was very tempted to buy one but did not.
While the old batt. was out I did take the oppertunity to clean the battery holder area well. I also added a battery hold down which was not there before. So now the for the first time since I have owned this 1979 B it is straped down securly. I know it probalby is not necessary, but a while back besides having the ground strap from the tranny to body, I aslo rigged a ground strap from the engine to body. I felt it never hurts to have an alternative gound. It is very intersting to know that the wire from the + battery terminal to the starter can go bad internally. This is something to keep and eye on.

Well, Thanks to all again. It has been a while since I have visited at this site. It is nice to see all the familiar names. If any one is in the Denver area the second week in Sept. you might want to stop by the "Colorado English Motoring Conclave" They are expecting close to 600 British vehicles to be in attendance this year. Actually, it is Sept 18th and 19th a two day event at Memorial Park. E-mail me if you need more info or directions.
John Fraioli
John F

This thread was discussed between 31/07/2004 and 02/08/2004

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