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MG TD TF 1500 - New TD owner - Brake switch & rack seals

Hello all

I am the new owner of a 1953 TD...my birthday present to myself! (see attached pic)

I have 2 items I need to replace and would appreciate any tips. I searched the FAQs and this BBS, but didn't find anything appropriate.

1. Brake light switch needs replacing as the lights always stay on. Seems like there is freeplay in the pedal-to-master cylinder and the car rolls easy by hand so don't think there's pressure on the braking system. Disconnected wiring at the switch and the lights go off.

Questions:
- Is there any secret to replacing the switch without getting brake fluid all over the place?
- Anything I need to do to make bleeding the system afterward easier?
- Anyone know the wire gauge at the switch? The old wiring was spliced and I would like to repair properly so need to pick up some new wire. Looks like 18Ga or 16Ga.

2. The Rack Seals are both bad/split and separated at the narrow end. I assume I will mark and remove the tie rod ends, take the old boots off and put the new boots/clamps in place then reinstall tie rod ends.

Questions:
- Any secrets to make this easier?

Thanks! Bill


Bill G

Bill -- I don't know of being able to change the switch without loosing brake fluid, but while you're doing such I would recommend installing the Brake Light Relay Switch, provided by Dave DuBois (http://homepage.donobi.net/sufuelpumps). The link below will take you to a section of my web-site that shows the installation of this relay switch. You'll just have to scroll down a bit to see the related photos.

http://mgtf54.blogspot.com/2012/01/dash-instruments-and-wiring.html

Very nice looking TD -- John
John Brickell

Congratulations on your new car and welcome to the MG BBS! You will find lots of experienced help here as you need it.
The brake light switch replacement will not require bleeding of any lines and will not leak as long as the brake pedal remains static during the replacement.
Someone else will undoubtedly provide info about the wire gauge to use.
You are on the right track with your plan to replace the rack seals. I believe they can/should be replaced with MGB equivalent parts which are a bit longer and provide more stretch than the originals on your car. Some of the other owners will probably comment on this too.
Good Luck with a great looking car.
Jim Merz

Bill - The existing wire for the brake lights is a British type of wire - 7 strand, which is approximately the equivalent of our 18 AWG. There are two wires going to the brake light switch, green which is the 12 volt feed, and a green/purple wire that goes from the brake light switch to the turn signal relay. While you can get the plain green wire from NAPA or other auto supply house, the green/purple is another story. I order wire for our MGs, along with other electrical wiring bits and pieces, up to entire harnesses from British Wiring http://www.britishwiring.com/ They have all of the proper gauge and color wire needed for the cars.

Considering the quality of brake light switches sold today (regardless of where you get them) is less than stellar (read - outright junk), that don't hold up well, failing anywhere from 2 weeks to less than a year. There are two ways around this problem. First, order a very expensive switch from Ron Francis Wiring http://www.ronfrancis.com/ (P/N SW-32), which holds up very well (although there have been reports that even this switch can fail prematurely). Second, pickup a switch from NAPA (ask for P/N 3H1894) and make or purchase a brake light relay/arc suppression circuit (See the article, Brake Light Relay in the Other Tech Articles section of my Homepage at: http://homepages.donobi.net/sufuelpumps/ ) and install it when you replace the switch. This circuit will keep the switch from failing (it has been over ten years since I installed the relay/arc suppression circuit with a new switch and have not had any problems since.

As I have been writing this reply, another thing struck me regarding your brake light problem. Since your problem doesn't fit the normal failure mode for the brake light switch, you might want to check further to make sure that the problem is somewhere other than the switch. As I stated above, the green/purple wire from the brake light switch goes, not to the brake lights themselves, but the turn signal relay and from there it is routed to the brake lights themselves. If you have a shop manual for your TD, you can follow the wiring diagram through the turn signal relay and see if there is a problem there. If you don't have a shop manual, e-mail me at SUfuelpumps@donobi.net and I can send you a diagram and help you troubleshoot your problem. Cheers - Dave
David DuBois

Bill,

Welcome to the BBS. Here is a second for installation of Dave's relay box. It is a trouble free solution to the failure of new brake light switches. Also, this would be a great time to add a high center brake light to supplement the little TD lights. I used a boat trailer harness available at any auto parts to make the added light removable for shows where the originality police can down score added goodies. Have a ball and drive your TD with pride.

Best regards,

Jim Haskins 1953 TD
J. M. Haskins

You can reset the track approximately by counting the number of turns to remove the track rod ends but it is highly recommended to get the track properly set afterwards. It will pay for itself in reduced tyre wear. Buy new bellow kits that have metal securing bands rather than plastic tie wraps. The latter are useless and the bellows will come off the rack, especially if there is any oil on the housing, as the steering wheel is turned from lock to lock. I have recently bought some from Brown and Gammonds and they are excellent.

Jan T
J Targosz

Thank you everyone for your help, much appreciated!

By the way, this car is still battery positive to the chassis.

I am trying to get it ready to go home in E. TN from its temporary home at my son's in Raleigh, NC. To do that I need to bleed the brakes, but figured I better swap out the shorted switch before doing that.

My assumption is that the brake light switch is just a normally open switch that closes when under braking pressure. Is that not correct?

I haven't completely traced the electrical wiring associated with the turn signals, but it seems to be added with a 3-way toggle switch under the dash on the left side (along with a fog lamp switch and a starter button). It works well and is very neatly done, but I didn't think its factory original. Did they come with turn signals that sound like that??? Based on the fact I haven't traced it yet I can't be sure it doesn't have a brake relay adapter already since somehow it had to tap into the brake light circuit. I was thinking I will do the switch first and adding the circuit if its not already there when I have more time after getting the car home.

I don't recall seeing colored wiring at the brake light switch, I think both wires were just dark grey and I couldn't tell the polarity, but assumed that didn't matter. There were 2 screw terminals on the switch, it pretty much looked OEM except someone had cut the wires about 4" from the switch and spliced them to the harness by wire twisting and electrical tape. Ugh.... So I want to fix that, but will probably just get some black cloth braid wire in the correct Gauge to fit the switch.

I will call NAPA and see if I can get that part number. appreciate the reference!!! When I called NAPA the other day, they had nothing to cross-ref with. I was just going to order one from Moss.

Regarding the switch troubleshooting, I disconnected the wire from the switch and the brake lights went off. The turn signals still worked. The turn signals also work with the (assumed shorted) switch connected with the brake lights "stuck" on, so I figured the circuit is working properly other than the brake switch. If the lights had stayed on when disconnected from the switch I would have assumed the fault/short was with the turn signal wiring.

BTW, I do have a shop manual with the car...both about 140 miles away from me.

On the rack boots I was getting ready to order the MG TD ones from Moss. Does anyone know the correct MGB part numbers to order (probably from Moss) if they are better?

Thanks again, Bill
Bill G

I found the MGB rack seals on Moss website p/n 263-380

Are these better to use than the TD rack seals (Moss p/n 281-378)?
Bill G

Found the Brown & Gammons ones...interesting that they state these are for MGB and TD/TF cars. Wonder if it is worth ordering from the UK to ship to the USA instead of the ones Moss carries in the USA???

http://www.ukmgparts.com/product.aspx?CID=fa7d90fa-a5e3-4200-8ef2-bfe88a81db74&SID=88fd8980-3c65-48c5-a71c-01c783dffaa8&PID=3bff2565-3180-489d-9ad3-de89221c8d70
Bill G

Bill, welcome to the bbs. Beautiful car. I think I know why the wires to your brake light switch have been cut and spliced. Shortly after I got my TD the brake light switch failed. After inquiring on this bbs I did swap it with no loss of brake fluid but I couldn't connect the wires to the switch after it was screwed in so I had to make the connections and then wind enough wire around the switch to be able to turn it enough times to fully screw it into the 4-way valve. A real pain. Next time I'm under the car I'm going to cut the wires and put bullet connectors on them so I can screw the switch in and then just snap the bullet connectors together.


BTW, I notice that your tail lights are rectangular. Mine are round. I think real early TDs were rectangular but I don't know when they switched over. Moss catelogue says the switch as at 21302. Have you checked the car number to be sure that yours is a '53 and not an earlier one?
Jud

'53 TD 25009 (born February 1953)
J K Chapin

interesting Jud, I hadn't thought about having to install with the wires attached. Do you know why the screw terminals wouldn't work once the switch was installed?

My car is #20468, titled as a 1953 but earlier than yours. I don't have a printed catalog from Moss and was selecting the switch from the web page which doesn't specify a starting car ID number.

Item 39 (p/n 141-700) from this web page:

http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32824

Wonder if the Moss part will work in mine?

The one David referenced above from Ronfrancis has a snap on connector that would make installation easier if you can't use the screw terminals once installed.
Bill G

Bill - If you are going to order rack gators from Moss, just order the brake light switch from them. They are no better or worse than any of the others. I am not sure why Jud had a problem of having to screw the switch in with the wires attached other than having to attach the wires while laying flat on his back under the car with the switch just inches from his eyes (Jud, I don't know how old you are, but at my age, that is a problem for me). Back to you Bill - The brake light switch is the same for all TD and will work on all MG up through the early MGBs. Get the MGB gators from Moss P/N 263-385 - they are a longer gator which makes them last longer, since they are not stretched so far. They will be a bit more difficult to install because they are slightly smaller in diameter where they fit over the end of the rack, but it is well worth the small amount of hassle to get them on.

Your car was built the 1st of Oct. 1952, which is why is is titled as a 53. By the time it got to the US dealer it was probably very late 52 or early 53. The Brits in those years didn't refer to cars by the year, on the model. That also explains the single pole, double throw, center off switch for the turn signals. Turn signals were not factory installed until car #22315 in Dec of 52. Someone purchased the turn signal relay and used the after market switch to install the turn signals in your car.

One final hint, use the Moss P/Ns and order the parts through Little British Car Co. http://www.lbcarco.com/ He gives a discount for the parts, plus his shipping is cheaper. Cheers - Dave
David DuBois

Bill, NAPA has two switches, SL144 and SL147. The SL144 uses 'grub screws', for bare wires. The SL147 uses push-on connectors. There's a bit more info on the relay at http://www.ttalk.info/Tech/BrakeLightRelay.htm. Bud
Bud Krueger

David, Thanks again for the details!

As I thought overnight about what Jud said, I can see it being a problem getting the screws out of the old switch because of corrosion and having to cut the wires before removing. That very likely was the reason the wires were cut.

BTW, I can relate to the pain it is working under a car since I have progressive lenses. On, off...upside down...how do I see this thing :-)

I'll get the MGB style gators. The Moss p/n 263-385 is the "original" and n/a, but the "replacement is 263-380 per the website.

I'll check out LBCarCo to see if they have what I need in stock. Thanks for the lead! Isn't it heresy having a British Car parts company in Farmington Hills, MI (suburb of Detroit)???? I have to admit I did think Moss' parts were reasonably priced.


Bud, Thank you also for the NAPA P/Ns

...Bill
Bill G

I just recently swapped out the NAPA SL 144 switch for one of the Moss jobs I had laying on the bench. The 144 requires (at least on my TD) higher pressure than normal braking requires for activation. It would only work if I were applying near panic stop foot pressure.

As for the rack boots... I'm not impressed with any of the rubber products sold by Moss for the last 8 years. Most of the new rubber bits fall apart within a couple of years regardless of use or car storage. I replaced the 7 year old Moss boots on the TF with some NAPA ones last year. Appear to be more of a urethane product. Not sure what the long term results will be but I can't believe they will be much worse. Noticed the 7 year old rubber steering bushings are falling apart as well and have a new set coming but I doubt they will last any longer.
L E D LaVerne

Hi Bill,
the boots are a pig to fit. My answer was to cut a hose clip end off then size it till it will fit over the rack housing. Fit this inside the boot then fit to rack and remove the clip.It is a darn sight easier than trying to fiddle it over in place,I don't seem to have enough fingers/hands to do this.
Ray TF 2884
Ray Lee

Hi Again, got these gaiters at a car boot sale (pun intended).
Note they have a protective disc where the clip goes.I have found that that is where my boots normally leak so I have cut out some rubber sheet to do the same thing on my boots.
I don't know what the boots are meant to fit as they have no markings I can see. The appear to be of a better quality than I can buy from MG stockists so I will have to keep my eyes open at boot sales.
Ray TF 2884


Ray Lee

While you have the boots off, check to see if the PO used grease in the steering box. Not an unusual find as there is a zirc fitting that a lot assume is for grease.
I used Kerosine to flush the majority of grease out of mine. A lot easier to do with the boots off.
Bruce Cunha

LaVerne - Thanks for the info on the NAPA switch, I'll stay away from that one for now. Any chance you have a part number for the NAPA (rack seal) boots?

Ray - Excellent suggestion on using a hose clamp to expand the rack seal/boot before installing. Those boots in your pic are nice.

That brings up a question...do the MGB rack seal clamps fit or do I need the TD ones. The MGB rack seal comes as a set with the clamps, but want to make sure they will fit.

Bruce - Thanks for the tip on checking the steering box when I do this.

...Bill
Bill G

LaVerne's experience with the SL 144 switch is the normal failure mode for these switches - they gradually require more brake pressure to close and light the brake lights. This is due to the burning of the contacts in the switch, which are very light duty contacts. My suspicions are that most, if not all newer cars use relays for everything requiring switched power. since the relays require a very small amount of current to operate, the switches of today have reduced the amount of copper in the switch contacts and as a result, cannot handle even the 2 - 3 amps required for the brake lights. This is why I advocate the addition of a relay when the brake light switch is replaced.

"BTW, I can relate to the pain it is working under a car since I have progressive lenses. On, off...upside down...how do I see this thing :-)"
At one time, while still working and having to look up into electronic cabinets, I to a page from airline pilots and got a pair of "double D" bifocals. These are bifocals with the reading portion placed both in the normal position and the others at the top of the glasses. It take a bit of getting used to, but one acclimated to them, it is much easier to work of things above ones head (I don't know if this will work with progressive lenses). Cheers - Dave
David DuBois

Dave D, I have a new fabric covered wiring harness. Will I need to run another wire to install your relay setup? Or, can I use the existing wires? I really don't want to add an extra wire outside of the original harness. PJ
Paul sr

Paul, see http://www.ttalk.info/Tech/BrakeLightRelay.htm for my wiring. You don't need to run any other wires. Everything is 'point-to-point'. However, you'll need to provide a ground point for the relay. The screw holding the relay in place can hold a lug for grounding. Bud

BTW, the NAPA SL147 switch shown in the 2005 image is still working fine and doesn't require any extra pressure.
Bud Krueger

Bill,
Not sure how (in)convenient it would be but if the car is in Raleigh, have your son go to T-Hoff on N West St and ask for MGB gaiters. They should come from World-Pac under a Jaguar part number (JLM-something as I recall) and are higher quality than the ones I've seen from Moss (the last set from Moss were too short for a B, maybe they fit a TD ok).

Or, get the switch and gaiters from The B Hive in Clemson SC. Gordon tries to only stock good stuff and he's one-day shipping from Raleigh. (Although now that Moss have their Petersburg VA warehouse they're *usually* only one day away, unless you're in a bind and need it next day, in which case it'll take several. ;-)

Good looking car! I like red TDs!


Rob Edwards

Rob - Thanks for the info... Only problem its now about 10 minutes after I placed the order with LBCarCo :-O If for some reason the rack seals (or gaiters) are backordered I will send him over to get me the good ones.

Thanks,
Bill
Bill G

Many people commented we had no brakelights- the problem was, the switch required very healthy foot pressure before illuminating. I scored a cheap 'Hot Rod low pressure switch' off ebay so the brake lights come on with much less effort.
JIM NORTHRUP SR

Nice car, Welcome to the BBS..
Tom Maine

There is reason to believe that rubber products purchased from Abingdon Spares are of a better quality than comparable items from Moss. At least that's MHO. Bud
Abingdon Spares: 800-225-0251
http://www.abingdonsparesllc.com/
Bud Krueger

Rob, any chance Gordon in Clemson used to run Europair? Back in the 60s that's where I had my TR-4 serviced.

Dave Du: 67 and not as spry as I once was.

Bill: the screws would work with the switch installed, I just couldn't get a scewdreiver to them.

Dave Du again: I now sport trifocals and I find when I have to work on a high cabinet or under the car it often works to just turn them over and wear them upside down. They don't stay on very well but at least my L-R prescriptions are close enought that the system works. I try not to let anybody see me 'cause it looks ridiculous.

Jud
J K Chapin

Jud - I am now in tri focals also - didn't like the progressives. I still have the double Ds but they don't work very well since I am about two prescriptions beyond them. I'll have to try putting my glasses on upside down, thanks for the inspiration. Cheers - Dave
David DuBois

Paul - As Bud posted, the wiring is all point to point wiring right at the brake light switch. When I make up the relay, I use a plug for the relay and it has all the crimp connectors to connect to the existing wire (the wire I use is all the correct color code). Cheers - Dave
David DuBois

Here's an update on Rack seals.

The 263-380 Moss part ordered from LBCarCo arrived with plastic zip ties, not metal clamps. I touched base with them and they said they have had trouble with the clamps fitting and have been shipping the rack seals with zip ties. They were not sure if they can get the metal clamps.

Thanks to Rob Edwards' recommendation, I contacted T-Hoff in Raleigh, NC and they were able to get me the MGB Rack seals same day. My son picked them up today and these DO come with the metal clamps! Now I haven't installed yet (it will probably be next week before I get back to my TD) but I will re-post and let everyone know how it went.

Bill
Bill G

This thread was discussed between 17/08/2013 and 23/08/2013

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