TR2/3/3A TR3 needs starting fluid to start?

[Jim Lee]

Hi all,

I need some of your expert advice on a TR3 that is refusing to start cold (meaning like overnight cold) without me spraying some starting fluid on the air filters. My usual routine is this:

1 - Try to start it and it just works the starter and tests the battery. Round and round without any hint of catching.

2 - Open up hood and spray starting fluid on both filters.

3 - Hop in as quick as I can and it will start right up and since I have the choke pulled all the way out it will rev much higher than I would like to on first starting.

4 - After about a minute it quits like it is running out of gas. I think, though am not sure, it is running a little bit longer than just on the starting fluid. I have an electric pump that is on from the time I turn the key and I know that this is working and getting gas to the carbs.

5. - Spray again. Jump in and it starts right up and as long as I keep the choke all the way out I can sit there for a few minutes and finally, very carefully lower the revs from like 3k to 2k.

6. When I can get the choke to go about half way in without stalling I can start out.

7. It runs great and as long as I come back to it before it gets too cold it starts up with a touch of the button.

The first thing I am going to do is replace the plugs mainly because it is the simplest thing to do but also because I am thinking this is most likely a spark as opposed to fuel issue.
When I use the starting fluid I suspect that it is so much more volatile than regular old gas that it doesn't take much of a spark to get it going. The car has not been used that much this winter but I have been very good on keeping the tank full and putting that gas preservative stuff in there. It has a full tank. The distributor and wires and rotor and all are practically new and have been checked out.

Thanks very much,
Jim Lee

 

[TR4]

If you had a spark plug tester, you could check your current plugs against new plugs to see if you think the new plugs give a better spark. You are starting where I would. Keep us updated with your progress.

 

[Don Elliott]

Jim - I have two suggestions.

1. You don't need to run around and hop in to start it. You can push the rubber button on the starter solenoid (if your key is on in the ignition switch) and it will crank over. See photo of mine. The rubber push-button is on the rear of the body and is about 1 inch in diameter.

2. I had my gas tank "slushed" in 1990 when I found a small leak. That epoxy-like liquid they used prevents the inside of my tank from rusting. I have stored my 1958 TR3A is a warm dry garage the last 20 winters and I leave the tank empty (or almost empty). Especially since gas has ethanol added to it now. Remove the hose going to your pump and add a similar longer hose, put the end of that long hose in a coffee can full of fresh gas. Put it somewhere it won't get knocked over. Try to start the car and if it runs for 5 minutes till the can is empty, you know that your problem lies with the old gas in your tank since last year.

 

[M_Pied_Lourd]

Just make sure that you don't have it in gear

Cheers,
M. Pied Lourd

 

[TR3driver]

Sounds like lack of fuel to me; in fact that is exactly the test I use for fuel delivery problems.

How far down are the jets moving when you pull the choke?

Are the float bowls clean? Float level properly set? Getting good fuel pressure?

How old is the fuel?

Weak spark could certainly explain why it needs ether to get going, but the inside of the cylinders gets hot real fast once it's running. Weak spark isn't likely to be the reason it dies, especially not like it's running out of fuel.

However, most fuel sold in the US these days has ethanol in it, which makes it go stale really fast, especially in humid climates. If you've left a tank of fuel sit since last fall, it may have so much water in it by now that it won't vaporize and burn unless the engine is hot.

 

[Jim Lee]

Just replaced the plugs and no difference. That is an excellent idea to test with fresh gas just before the pump. I do not know why I have not been using the push button under the hood/bonnet. I sure have used it before. As my mother-in-law might say "That was dumb". I bet it is the old gas. I was thinking I was ok because I was so good about keeping the tank full (thus less space to condense water inside) and using Sta-bil or whatever that stuff is that is supposed to keep gas dry. I think that i just learned this lesson with a chain saw a few months ago with the old gas problem. That was even more fun because instead of a starter motor I was using my right arm which was mad at me for days after my chain saw pull fest. I finally got the tip to splurge and mix up a new gallon of gas and it started running like a champ. Don't tell anyone but I returned two saws in the mean time.

What I am real curious about though is why the gas would start working after warming it up for 5 minutes or so? Is it because the detonation area, the cylinder, is so hot that the gas does not have to be that ignitable (sp?) when it gets to a certain temperature?

I will report back.

Thanks all,
Jim Lee

 

[TFR]

Has to be a lean condition. Choke cable linkage not pulling down the jet tubes enough. If it won't start when the choke is pulled but will start when ether is sprayed then there is a lean condition.
The SU carbs are beasts until you get them set properly. Then the only thing to do is maintain them with fresh fuel and a little dampner oil.

Of course this is just my .02

 

[Mkutz]

I'd rebuild the carbs with a fresh set of replacement SU parts. New seals, jets, needles, everything, and figure out where you are after the rebuild. I spent six months diagnosing some carbs that were rebuilt by a "professional" rebuilder. The problem was was that the front carb was running continuously too rich compared to the rear carb, even with the mixture nut turned all the way in. Lifting the piston AND Gunston confirmed this as true. The problem?

Turns out to be two things: 1. The brand new jet tube on the front carb was a full 1/16" of an inch shorter that the tube on the rear carb, and 2. the upper jet bearing seal (copper) was around .046 thich wheras the stock should be about .015 thick. Each problem forced a lower relative position of the tube, which created a rich condition.

I agree, must be a lean condition caused by fuel level (floats), or gunk caught in the jets, or improperly set mixture settings. Try this-turn the mixture nuts all the way in, then back out two full turns (12 flats) and see if it will fire up. Also, make sure the jet tubes are being pulled down 1/4" or so when the choke is pulled. Also, get the air cleaners off, and see if the pistons are free to move up and down and the needles aren't binding up in the jets.

 

[Deleted member 8987]

Not LBC related, but, back in the early 80's with GM emission controlled cars, we had an issue like that.
There needed to be a minimum amount of cranking vacuum (can't remember exactly....6-8").

Worn guides did 'em in, along with worn rings.

They'd come in on a hook, first thing we did was stick a vacuum gauge on it and crank.

What is your cranking vacuum?

 

[vivdownunder]

Almost certainly fuel delivery related.

Here's a couple of things to check.

Disconnect the fuel line to the rear carby and feed it into a bottle to prove fuel is arriving at the carbies. Take the electrical supply wire off the coil first, so ignition is not possible. Be careful not to spill fuel.

Remove the air cleaner on the front carby and check when you pull the choke that the jet drops. That's essential to enrichen the mixture for start up, as an SU carby has no squirter pump.

Check that the choke isn't quietly returning to normal via the return springs before you turn the key. A clothes peg, or coin on the flat behind the choke knob will stop it playing tricks.

It's been mentioned before, but you only need the choke operating on the front carby. This avoids the "foot on the dash" syndrome to pull the choke out. Disconnect the lower choke crossbar between carbies.

Once running, to stop the engine revving like crazy, look left side of the front carby. There's a vertical screw that hits a cam. Wind it back so it just starts to hit the cam when the choke is out. The choke cam should only slightly increase engine revs during warm up.

Good luck with sorting it,

Viv.

 

[Jim Lee]

As usual you all addressed my issue spot on.

All excellent advice that I am going to check out but it looks like the winner was to remove the fuel line before the pump and stick it into a gas can full of brand new gas. After it dealt with what might have been an ounce or two of old gas in the lines it started right up and did not insist on running at 3k rpm for minutes to get under power. I had this false sense of security that if I kept the tank full and dumped enough Sta-Bil gas dryer/keeper in there it would be fine. I was told that if you do not keep the tank full, or as close to it as possible, that the air space allows condensation to form and that is how you get water in your gas. An accumulation of day after day humidity as we see here in North Carolina even in the winter months.

Would it be better to drain the tank in the future if it is not going to be used for a month or two? What do you all do when you are pretty confident that you will not be driving it for a while?

Thanks very much for all the great help.

Jim Lee
TR3A 1959 Black on Black Beauty
Raleigh/Durham North Carolina