• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

High Beam/Turn Signal switch issue?

Share this page

77MidgetMkIV

77MidgetMkIV

Jedi Trainee
Country flag
Offline
Hey all- the first gremlin has already appeared in the 3 days since being back on the road- Last night, I was headed out to meet some folks, and all was good. Got on the road, and when I went to hit high beams, headlights went OUT. putting back into low beams restored the lights, and when pulling the lever, the brights do come on, so I know the power and the lights, etc are good. Sounds like the switch just went? FWIW activating the left turn signal always seemed not to click very strongly....

In any event, looking at Moss they have the turn signal/dimmer for my 1977- I am assuming that by dimer they do mean high/low beam? Can anyone comment on whether the one from Moss is a good replacement unit?

Thanks in advance for the assistance!
 
It's as good as it gets but consider adding headlight relay kit. Takes load off of that switch, lights are substantially brighter. Moss relY kit on sale now for 34.95
 
The answer to every British electrical problem is - check the grounds first!

That said, I have had similar issue and replaced the light switch (would take two or three tries for all the lights to come on) took the signal switch apart and cleaned thoroughly - the signals would work randomly - and, I think the hazard switch is a big deal - It's been a few years but a number of circuits go through it.
 
Jim_Gruber- that is a good idea on the relays- I had done a similar thing on an older Jeep I had, never thought about it for the MG-the switch seems wonky even on locking into the turn signals as well, so I am going to pull it and clean it, but I am going to replace it as well.

JPSmit- good call- I had checked all the grounds I could over the past couple weeks and it is all in order. One tidbit is that I still have regular access to the PO since he is my cousin and is also an avid LBC enthusiast, and BC owner in general- he said that he had replaced that switch with a cheaper aftermarket a long time ago out of need as he had to pass inspection and it was the only one he could get at the time.

To everyone- I pulled the stem off the turn signal and tried to get the cowl off, but it just won't slip out- is this something that I will need to drop the steering column for? If installing the relay kit, will that require pulling the column? Not too scared of that since I have done it in other more complex vehicles, but I might start on the PB today if I need to do so, since I am away all weekend!
 
Yes I believe you have to drop the column to get the cowl off - you will also have to (IIFC) grind slots into two "permanant" screws to get it apart.

Re-reading the first post.

1. While relays are great (I have them) they have nothing to do with the problem, so, fix the problem, then add relays. You do all that under the hood and none of it by the steering column - In a nutshell the existing power to the headlights will power the relay and a new line from the battery will power the lights - schematic can be found here - https://www.advanceautowire.com/

Will try to take a look at a schematic to refresh my memory on the original issue
 
thx JPSmit- so I did what I should have done before I asked, which is look the relay kit up and read the install sheet. it is just like the other one I built up for my Jeep-all under the hood. Also, understood that the relays etc are not part of the problem, it was more of a thought that if the relay kit needed to go up to the switch, I would buy it now while I had the column down, but looks like I can do that any time.
 
Had a similar issue when I first bought the car. The seller (longbridgehealey on BCF) replaced the switch and the turn signal stalk, no more problem. One time, I was driving and thought the brights were completely inoperative. It took me about 15 minutes to realize that I was pulling back on the wiper stalk, which, inexplicably, has the same kind of fore and aft motion the turn signal / dimmer does on the left side.
 
SaxMan said:
Had a similar issue when I first bought the car. The seller (longbridgehealey on BCF) replaced the switch and the turn signal stalk, no more problem. One time, I was driving and thought the brights were completely inoperative. It took me about 15 minutes to realize that I was pulling back on the wiper stalk, which, inexplicably, has the same kind of fore and aft motion the turn signal / dimmer does on the left side.
Click to expand...

Not relevant to this thread but, it is the same stalk as used in MGB where it is used as the overdrive switch. I used mine for a driving light.
 
JPSmit said:
Not relevant to this thread but, it is the same stalk as used in MGB where it is used as the overdrive switch. I used mine for a driving light.
Click to expand...

Thanks for the explanation.
 
My DOT inspection tech was very understanding given the nature of the car, and the car was allowed to pass inspection despite the switch- he has inspected a number of my cars and knows that I keep up on things. This gives me a little breathing room to plan when I take the steering column out and do the work. He did say that my TRE are starting to show some wear, so I am thinking that there will be a combined wrench day in early fall to get the switch, install the relays, do the TRE, and a couple other things. I am now onto diagnosing the perpetual low oil pressure when hot- I am hoping that it is just the thrust washer and rod bearings since I understand these can be done with the engine left in the vehicle. Anyone have direct experience in that work? Should I plan on replacing the oil pump/et while I am in there? what else can be done while I have the pan dropped? If I am going to open it, I might as well do what I can.....
 
I did some reading up on thrust washers, etc, and figured that I would take a look with the pry-bar test. Hoping someone can tell me if I am wrong on this, but I basically used a pry bar behind crank pulley and pryed to the front end of the vehicle-there seemed to be no play, and then depressed clutch while videoing with iphone- no movement...Did I do this test correctly? Is the test generally reliable? As stated above, I am moving on to looking into my low oil pressure when hot@idle-can go low as 10psi, maybe a hair below- always perks back up as soon as throttle is applied, but I don't like it. Driving at moderate load is ~40ish, and prolly 60 when starting cold.
 
77MidgetMkIV said:
I did some reading up on thrust washers, etc, and figured that I would take a look with the pry-bar test. Hoping someone can tell me if I am wrong on this, but I basically used a pry bar behind crank pulley and pryed to the front end of the vehicle-there seemed to be no play, and then depressed clutch while videoing with iphone- no movement...Did I do this test correctly? Is the test generally reliable? As stated above, I am moving on to looking into my low oil pressure when hot@idle-can go low as 10psi, maybe a hair below- always perks back up as soon as throttle is applied, but I don't like it. Driving at moderate load is ~40ish, and prolly 60 when starting cold.
Click to expand...

That sounds a whole lot like mine even with the engone refreshed. I drove to Wisconsin and back on 40-45 lbs on startup and 5 lbs hot. Unless you plan to refresh the whole engine, I wouldn't even bother. I did put a new oil pump in mine - made a huge difference - note BTW that the pickup is different on a new one from Moss - apparantly better - works fine. Then run 25% Lucas oil stabilizer and the drive it like you stole it. Truly the oil pressure you describe is truly the oil pressure these cars come with.
 
JPSmit- thanks for the input...I don't run any additives in my oil on a permanent basis- I sometimes will run seafoam in the sump for a few miles before a change-I am however going to be changing the oil in a couple weeks, as I am still running my 'out of hibernation' oil-I'm re-doing all fluids at the 250 mile mark since reviving. I am going to try the lucas and see how it goes-any issues mixing with synthetic? (I run mobil 1, site says no issue but you never know)...you make me feel better about driving it to work one of these days...I drive 35 miles but almost all highway, and a LOT of Boston stop and go....
 
What is the pressure when hot at say 3- 4K??
 
I will have to re-run that test but probably around 50?

Im taking it to a car drive-in tonight so I will see but it is not that hot out today.
 
77MidgetMkIV said:
JPSmit- thanks for the input...I don't run any additives in my oil on a permanent basis- I sometimes will run seafoam in the sump for a few miles before a change-I am however going to be changing the oil in a couple weeks, as I am still running my 'out of hibernation' oil-I'm re-doing all fluids at the 250 mile mark since reviving. I am going to try the lucas and see how it goes-any issues mixing with synthetic? (I run mobil 1, site says no issue but you never know)...you make me feel better about driving it to work one of these days...I drive 35 miles but almost all highway, and a LOT of Boston stop and go....
Click to expand...

Not sure how Lucas works with synthetic, but, I personally am leary about using synthetic in our cars. Synthetic didn't exist then and I use the oil they were built to use. This is partly because I don't put on the miles to warrant the extra cost - I change my oil yearly and haven't even come close to the oil change mileage for a number of years. I believe Synthetic is slipperier than conventional which is great for modern tolerances but, not so much for ours where the tolerances are measured by guess and by golly. And, not all synthetics (or conventional oils) have the zddp necessary for flat tappet cars.

I use Castrol GTX 20W50 with 25% Lucas and I find it plus the new pump have added to the presuure perfectly. Remembering that your pressure is just fine already.

cheers!
JP
 
so, I normally use the mobil 1 v-twin 20w50- marketed to motorcycles, but was recommended to me a while back-has plenty of zddp for our engines.....consensus is that my pressure is ok, but I wouldn't mind seeing it a bit higher- might try a run with lucas and see how it behaves.
 
77MidgetMkIV said:
so, I normally use the mobil 1 v-twin 20w50- marketed to motorcycles, but was recommended to me a while back-has plenty of zddp for our engines.....consensus is that my pressure is ok, but I wouldn't mind seeing it a bit higher- might try a run with lucas and see how it behaves.
Click to expand...

Motorcycle oil was recommended to me as well - used it (convetional oil) before realizing that Castrol was fine - sure sounds like you are on the right track.
 
50 PSI at reasonable revs seems OK, seems like the Oil pump is not he issue
However, 10 PSI at idle seems a little low. Personally do not like motor to be less than 20-25 at idle when hot.
Just because it is easy, have a look at the Oil pressure relief valve. Look for any signs of wear such as a groove or such in the piston.
Leakage through the relief valve could cause low PSI at idle
You could turn the motor by hand with the valve out to "flush" the seat of any possible debris.
If there is no problem with the relief valve then I am afraid it is the bearing clearances. I know it can be done but without a proper lift To raise the car I would not try to change bearings with the motor in the car and even then it is not a simple job.
 
Joe- it was my understanding that the pressure relief valve only controlled pressure at the high end, not at low end- am I missing something? As for the bearings (rod, that is), they are on my mind. I am not afraid of tackling them but won't be until the winter. I think having the midget up on standards should be sufficient, but I think I can get access to a lift through a connection if needed.
 
Back
Top