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MG TD TF 1500 - Tickler Pins - TD SU Carbs

I suspect there are many threads on this but I'll start a new one anyway. The carbs on my (TD25009, Feb '53) TD both have provisions for tickler pins in the float bowl covers but both have been rendered by DPO (?) inoperable. The picture attached below shows the front bowl. The DPO apparently just forced a sheet metal screw into the hole to seal it. As shown in the attachment to the next post, the DPO appears to have pushed a rubber tube onto the tickler pin to hold it up due to, presumably, a defective or missing spring. On to the next post. Thanks for your patience.

J K Chapin

The picture attached to this post is the rear float bowl cover with the rubber tube shoved over the tickler pin.

Questions:

Should I just leave it as is since it seems to work?

Should I get new pins and springs (Moss 375-045) and install them (the holw in the front float bowl may have been irreparably damaged requiring the investment in a new float bowl cover (Moss 375-058)?

Should I remover the sheet metal screw in the front cover the whatever remains of the tickler pin in the rear cover and seal the holes with JB Weld?

Thanks for your help.

Jud

J K Chapin

Personally, I would do whatever is necessary to rejuvenate the tickler pins. But, not everyone agrees with this philosophy. Bud
Bud Krueger

I agree with Bud. I think that the danger of a fire starting due to over flow past the tickler pins, while it is a valid concern, I have not experienced, personally see, or even heard of that occurring. A lid and tickler pin in good condition, will not allow much of the fuel to escape around the pin even in a stuck needle valve situation - the vast majority of fuel will exit through the vent tube. Cheers - Dave
D W DuBois

Two very respected opinions - thanks. New tickler pins (and new bowl covers if needed) will happen - I already have the master SU kit so I should have all the necessary gaskets.

Jud
J K Chapin

Two very respected opinions - thanks. New tickler pins (and new bowl covers if needed) will happen - I already have the master SU kit so I should have all the necessary gaskets.

Jud

ps: I meant to mention that I guess I have 40 years of experience rebuilding SU carbs - Rebuild (with considerable outside help) the SUs on my TR-4A (sadly long gone) back in ~ '75 and now doing the SUs on the TD so that's 40+ years.

JKC
J K Chapin

If tickler pins were necessary (and were a good thing), why did SU stop using them?
Gene Gillam

Like everything else... cost?
Steve S

Jud -

The ticklers on my TF-1500 had been replaced with screws similar to yours. I installed ticklers from Moss. There was a discussion about fuel leaking from the opening around the ticklers about the time that I installed mine.

Click this link for the discussion and a couple of "fixes." The rubber gasket on my "fix" is still good - hasn't dissolved in the fuel (non-ethanol).
http://www2.mg-cars.org.uk/cgi-bin/or17?runprog=mgbbs&access=&mode=archiveth&subject=8&subjectar=8&thread=200610111124558745

Lonnie
TF7211
LM Cook

Be aware that the new pins may not fit. On mine, while never plugged, the original pins had rattled around and worn the hole open. The new pins were very loose.
Your screws may have done a similar thing.

I drilled open the holes, made aluminum bushings which I Locktited into place and that took care of things.
Of course, not being able to leave things alone I made some other mods but I wont go into that.

Jim B.
JA Benjamin

I. on the other hand have see two disasterous fires due to stuck needles and consequent overflow via tickler pins, and a third overflow, fire averted. on startup, all on TF's in our club. The latter, I saw the cascade of fuel from about 20 feet away so I could see under the engine as he turned on the ignition, and I shouted for him to stop.

Dave, I disagree, lots of fuel was coming out the top in spite of the overflow tubes in place.

The TF we are currently restoring had in the past a carb fire also.

My choice, safe is better than sorry! My ticklers have been removed and plugged, The tops are there for show,

How many of you have ever needed to use them? I never did in 50 years of ownership of my TF 1500. Why risk it?
Don Harmer

For many years with a rusty tank and no filter, a float needle would stick on start up, and gas ran out mostly through the tickler pin holes all over the place. Fortunately, I knew to wait to crank it until the pump stopped clicking, or there could have been a fire. At restoration, I JB welded them in place, as the bowl is well vented through the overflow, and the old (well made) grosse jets never stick. George
George Butz

I am going to guess that the sheet metal screw in the front bowl lid will not have changed the shape of the hole much. It may have cut a thread, but if it has not cut into the bottom side it should still have a surface that the tickler pin seal will rest up against. Try it and find out!

I replaced the tickler pins when I first got my TD and even though they were loose in the hole they have never leaked, as they have a good seal on the under side.
C.R. Tyrell

George and Don point out what I was trying to say. They're potentially dangerous and SU stopped using them.
Gene Gillam

I had mentioned this before but forgive me for repeating.
When I mad the sleeve for the new pins I also extended them a bit above the level of the overflow tubes.

And yes it does require custom pins.

Jim B.

JA Benjamin

Isn't there supposed to be an o-ring there to prevent fuel overflow through the pins?
Steve S

Years ago, I installed new tickler pins as part of the rebuild of the carbs ... I hadn't read about the possibility of fires or anything else about them, I just assumed that stock must be good, end of story.
Since then, I've not seen problems with them and no flooding. I don't know what else to say except that the argument going on in this thread (and many in the past) isn't capable of a solution.
The fact that SU stopped installing tickler pins doesn't inherently mean that tickler pins are bad; it just means that SU moved on to something they thought was better or safer.
And if we replaced everything on our cars with something that was better or safer... let's be honest, there wouldn't be much original stuff left!!!
Geoffrey M Baker

I removed the pins and plugged the holes over 45 years ago and have not had any problem. I think they were discontinued by SU as a result of complaints that the pins would drop down and effect the float level.

George
George Raham [TD4224]

This thread was discussed between 04/08/2014 and 05/08/2014

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