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NickMorgan

NickMorgan

Jedi Knight
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Well, I have to eat humble pie.
Here I was telling Tom (Nutmeg) how easily my choke cable pulled out and discussing with Harry and Don the position of the connecting rod, where various parts are connected and how far the fast idle cam moves on my car.
I was trying to advise Tom on what should happen when a little spark went off in my brain. My TR3 has been a bit reluctant to start from cold. I would pump the fuel through by hand, pull the choke out its full one and a half inches and press the starter button for about ten seconds. Then I would try again, and again. Eventually it would fire once and stop. After another couple of tries it would eventually start (if the battery lasted long enough).
I went out to the garage to take a picture for Tom and noticed that my choke lever wasn't as far back as I expected. To cut this long story short. My choke was also not working properly and I followed the advice already posted for Tom, dismantled the carbs and put grease on the cork washers and glands.
And now ... my choke knob pulls out a full two inches, both jets lower and the car starts almost as soon as the starter moves the fly-wheel.
Thank you British Car Forum. You have just solved a problem I didn't know I had!!
 
Hey Nick - glad to hear the news! I figured you'd experience an epiphany once you got the jets to drop.

When I first discovered my jets weren't lowering and got that fixed, it was like a whole new car. Now it starts from cold on the first crank.

Working with someone sure helps see things in a different light. Thank you Nick - and thank you Forum!
 
I'm gonna go out to the lab and see if my jets lower!

Er... when it warms up of course...
 
uhhh...what's a jet?

Where do I look to see if it is lowering?

Or is this a TR3 thingy?

d
 
It's a TR3 thingie.
 
Or more generally an older SU thingie.
 
You're too clever, Don
 
I'm going after my jets this weekend. Is there a special grease for the cork? Wheel bearing grease or gasolene resistant grease?
 
John , if you see jets lowering it's most likely due to the military being a bit concerned about what is going on in the lab there at Soggy Bottom.
 
I just used regular wheel bearing grease. I think there is an answer from a knowledgeable member on the forum under H6 carb jet bearing assembly.
 
Dale -

Step away from the car sir. Please sir, do not touch your carbs for any reason. This was a TR3 teaser.
 
I wonder if a small amount of grease or lithium grease on the jets of my TR3 SU's would still have the same effect, seeing as how I put in the rubber O rings when I rebuilt my carbs ,as I'd heard the cork washers tended to leak? Maybe the rubber is binding against the jet? Might be worth a try to lubricate there. Another phenonomon I noticed was that the return springs(new ones) dont have enough oomph to pull the jets back once you push the choke back in. I rigged up a return spring from the front jet lever to the metal clip that holds the headlight wiring and after experimenting with spring length it seems to pull the jets back where their supposed to go. I wonder if any of us are driving around with their carb jets down somewhat creating rich mixture when driving? Karl /bcforum/images/%%GRAEMLIN_URL%%/crazy.gif
 
Ouch Paul,

Too late-

I unscrewed the two black cover caps on the carbs
and squirted some lithium grease inside.

Crypty should run much smoother when I crank him
up on Sunday!!

d /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif /bcforum/images/%%GRAEMLIN_URL%%/crazyeyes.gif
 
Karl - you mention the new return springs. Do you mean the springs that Moss sells?

Is your choke knob really tough to pull? Mine took two hands and a lot of body weight to move beyond 1/2 inch.

When you pull your choke knob out, what's the distance from the instrument panel to the back of the choke knob? about 1.5-2 inches?

How much of the jet assembly do you see when the choke is fully "out"? about 3/8 inch?

If you're not going to fully remove the jet assembly and put bearing grease on those o-rings, I'd at least try fully lowering the jet assembly and dabbing on some vaseline. Others here have much more experience than I do in all this.

Dale - for heaven's sake, pull those two black cover caps off again and toss some sand inside. Lithium grease is way too slippery. Jeez ....

Tom
 
TRclassic3 said:
John , if you see jets lowering it's most likely due to the military being a bit concerned about what is going on in the lab there at Soggy Bottom.
Click to expand...

Won't do them any good. I've wallpapered with tinfoil.
 
White lithium, or petroleum jelly would work well. I generally use WD-40 when re-assembling carbs and use the petroleum jelly on the jets. I also like to use a light machine oil to keep all the little moving bits moving. Sewing machine oil, or 3-in-1 oil work well.
DO NOT use any penetrant oil like B'laster PB. it will dissolve the cork gaskets (don't ask me how I know)
I've actually resorted to using valve lapping compound and or emery cloth on new jets before. Sometimes the new jets supplied in the SU rebuild kits just don't slide in the housings well.
Those methods I use before re-assembly, and I take extra care to thouroughly clean all the bits before they get put together for the final time.
 
A little late on this but as Banjo said, Petroleum Jelly on the jets and corks is what's recommended and listed in the Kenneth Ball, Autobook manual.
 
Ah yes, good old Vaseline to the rescue, once again!

And I think that Dale was kidding about adding grease to his oil.

You were kidding, right Dale?
 
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