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David_George
02-27-2009, 10:52 AM
I have a close friend with a 78 Midget that is having all kinds of electrical problems. He sent me an email which I copied and pasted here. Does anyone out there have any good ideas? He rather frustrated and I'm just trying to help....thank you all in advance.
How are you with the electrical stuff? I'm pretty frustrated with it all. Brake lights don't work and I recently lost all the dash guages. I don't know what happened. No horn, wipers, etc. The only thing working in the speedo. the lights in the guages work, but no functionality. It's really odd. Checked all the fuses and they're good. I can't seem to nail down the single point of failure.

bill_young
02-27-2009, 11:19 AM
I can't say for sure, but these type problems are typical of poor connections in the car. The bullet connectors and spade connectors tend to corrode and cause poor contacts. Another area is the male spade connections on the fuse block, the corrode between themselves and the rivets that attache them to the fuse clips. I suggest he start by cleaning the spade connectors going to the fuse block, you can use a small cup or spray can cap full of CLR and dip the connectors in that for a minute then rinse and dry, usually does a pretty good job. If he knows how to solder then I also suggest removing the fuse block and after cleaning it in CLR soldering the male spade connectors to the rivets on the back side. This takes a good amount of flux and a higher wattage iron or soldering gun, but it has fixed several intermittant electrical problems for me over the years.
It wouldn't be a bad idea to keep on going through the connectors and cleaning them one at a time anyway to prevent future problems. If any of the bullet connectors seems to pull apart too easily check for cracks in the female connections, they tend to crack and loose tension which can also cause intermittant connections.

JPSmit
02-27-2009, 12:34 PM
Welcome your friend to the wonderful world of Lucas!

Just spent a minute looking at my wiring diagram and my best guess is that he needs to be looking at the spade connector with the green wires coming out of the fuse box. That will cover most of his issues - except the horn which should be the purple wire coming out of the fuse box.

Tell him to

1. confirm continuity across the fuses - a visual check won't do (I'm not insulting if he already has.)

2. check voltage at the green side of the fusebox

3. If he can post a specific list, we can try to help some more. For instance, speedo is mechanical so will work, tach isn't etc. etc. I'm expecially interested in whether the signals/ hazard flashers work.

Finally, tell him(?) to get some dialectric grease and grease every connection checked - AND - sand and check every ground (black wire) found.

we can do this!

lbc_newbie
02-27-2009, 05:33 PM
Hey fellow MG Midget/Spridget owners! I'm the friend Dave was asking for. He was nice enough to introduce me to this forum. I would really like to thank you guys for coming through on this! JPSmit nailed it with the fusebox lug and the green wires. As soon as I applied a little pressure, the gauges lit up! Looks like a fuse box is in order. A small piece of foil on the end of the fuse seems to be doing the trick for now. I have EVERYTHING working! Blower motor (thought it was a bad switch), brake lights (thought it would cost a fortune to diagnose), temp and fuel gauges. I'll check the tach when I start it up (carb is on the work bench). Glad to have friends like you guys out here. I'll be in touch as I restore my Midget! THANKS!!

Sarastro
02-27-2009, 05:47 PM
You probably don't need to buy a new fuse block; just make sure all the connections are OK. If the spade connector on the wire is bad, for example, a new block won't do any good anyway. Solder the connections on the fuse block, as Bill suggests, and if necessary replace the connectors. Use a voltmeter to find precisely where the break is--you will have voltage on the upstream side of a connection but not below it--then that's the bad point. This is easiest to find if the electrical device it feeds is turned on.

lbc_newbie
02-27-2009, 06:01 PM
Thanks, Steve. I applied power and disconnected the green wires. I checked the voltage at the lug and it was all over the place. Upon inspection of the fuse box, there really isn't a whole lot to go wrong. I'll see if I can solder everything up and try it again.

JPSmit
02-27-2009, 09:14 PM
welcome on board - we're glad you're here - this is an awesome place, they have saved my bacon more times than I'm willing to admit - great people too. I have spent literally hours getting my wiring sorted and am almost there. One suggestion if you don't already have it is a couple of manuals - Bentley & Haynes (get both) You can buy laminated wiring diagrams on ebay but I just took the wiring diagram to a copy shop got it blown up and bought some markers. Then a continuity tester and a meter and I was good to go. we'll tell you about relays later.

In the meantime, introduce us to your car. :driving:

lbc_newbie
02-27-2009, 10:35 PM
I put my car out in the gallery. It still has a ways to go mechanically. Steers weird, brakes are spongy (even after complete flush and bleed), runs rough (have the Weber off to rebuild), just finished some crankcase ventilation issues. It's a strange car. "Barn" find here in Washington. Blown rear end. I couldn't drive it, so I took a chance for $1,000. It has a 1275 with a Datsun 210 4-speed. I hear this is a common thing. However, getting the freakin' vacuum lines and crankcase ventilation figured out is puzzling. Not to mention all the other ghosts this thing has. I'll post more pics later. Thanks!

JPSmit
02-27-2009, 11:02 PM
looks sharp - FWIW you ave $1000 worth of rims and weber already so anything after that is gravy. I still have the 1500 - so congrats on the 1275 - though mine is converted to chrome bumper which makes me happy.

https://tinyurl.com/6q6srd

you might want to look for a 210 5 speed as it should bolt right in

front end is an easy rebuild if it is tie rods etc - most of us have done that plus bearings.

If brakes are spongy but Master Cylinder Ok, might be rubber hoses needing replacing or if you used DOT5 they are likely just spongy

bottom line, you're at the right place and these puppies are VERY simple

lbc_newbie
02-28-2009, 11:58 AM
WOW! I just visited your site. I wish I had the time and the courage to strip mine down that far....not to mention the $$ resources. I have the chrome bumpers, but sold the grille when I could not figure out how to adapt it to the 78. I might just hold on to the bumpers and look for another grille now. When I found that the fenders needed to be replaced, I chickened out! Your's is stunning.

lbc_newbie
02-28-2009, 12:30 PM
I was inspired...here are some progress pics

https://www.flickr.com/photos/lbc_newbie/

DrEntropy
02-28-2009, 06:02 PM
A couple hints about the fuse block & electricals:

Sometimes a bit of tension on the "prongs" holding the fuse ends works wonders. Clean the surfaces in contact with the fuses with ScotchBrite red. Non-conductive abrasives. Same for the spade and bullet connectors. Solder any and all joints, as copper corrodes and introduces resistance.

"ScotchLoks" and other mechanical connection devices are the enemy. Dielectric grease is your friend. Twisting two pieces of wire together and wrapping it with black tape is NOT an electrical connection.

Ground points are ALWAYS subject to corrosion. Clean and grease every one you can find.

Putting an extra or external ground wire on every light assembly is NOT a sin... it's PRUDENT.

....I'll relenquish th' soap box now.

:jester:



<span style="font-style: italic">EDIT: OH! And WELCOME to the forum!!!</span>

JPSmit
02-28-2009, 11:01 PM
WOW! I just visited your site. I wish I had the time and the courage to strip mine down that far....not to mention the $$ resources. I have the chrome bumpers, but sold the grille when I could not figure out how to adapt it to the 78. I might just hold on to the bumpers and look for another grille now. When I found that the fenders needed to be replaced, I chickened out! Your's is stunning.

Thanks - I'm loving it - of course I'm also five years into a 2 year project. I was just looking at you Flickr pics and I wouldn't touch a thing. Yours looks great in white and more to the point is in great shape - the accident mine was in and the fact that it needed to be torn down as it hadn't run in 13 years made the changes a no-brainer.

The conversion is not too difficult, a few on the board have done it - you can keep the fenders and make the square signal lights fit. I went for the beehive since it was all apart anyway. The easiest way to do the conversion is no bumpers. but, the full monty is

Front

change bumper mounts front - install bumper
cut off old mounts to allow grille to fit
put 1275 front springs in place of 1500 front springs
sort out signals

Rear
figure out way to reinstall/ replace bumps under rear lights
In my case get brackets added for split bumpers
de-arch rear springs 1 inch

and Bob's your uncle BUT as I said before, yours is pretty enough as is, I think the stance is great and the touching up you have done just makes it right
that

JPSmit
02-28-2009, 11:01 PM
PS looks like your helper is having fun too

bthompson
03-01-2009, 12:17 AM
Keep in mind, if you don't want to make the conversion "permanent" like JPs, (like if you want to be able to stick the bumpers back on in the future for some reason,) you can do the quick'n'dirty conversion.

Like JP said, the rubber bumper lights "just happen" to fit in the holes in the fenders, just make a lil' clip to hold 'em in place from the back.

The sprite-style grills <span style="font-style: italic">will </span>flush mount in the grill opening without having to cut back the bumper mounts. Just press it over the two bumper mounting studs (they also "just happen" to fit over two grill slots!) and hold it on with large washers and nuts. It's not recessed like it's supposed to be, but still, it's better than a big black rubber nose, and easily reversible if the need arises.
https://i92.photobucket.com/albums/l39/W_J_Thompson/mg/mg1.jpg
For the bit that's cut out under the taillights, if you're not too picky you can just leave 'em as-is. I made tips out of styrofoam, bondoed it all smooth, primed and painted them, and stuck them on with 3M adhesive. Finishes off the fenderlines, and, again, is reversible.
https://i92.photobucket.com/albums/l39/W_J_Thompson/mg/mg3.jpg
You can also turn your licence-plate holder upside down; it'll sit about an inch lower, and looks a little better without the bumper under it.