TR6 TR6 won't start

[Phil73]

I’ve been a long-time participant on the 6-Pack forums but never posted here before. Hopefully someone on this forum will have some ideas on how to solve a problem that has literally been keeping be awake at night for the past 2 nights. 6-pack forum has been really helpful but it seems like we're running out of ideas at this point.

About a month ago I took my 73 TR6 out of winter storage and began an effort to refurbish the engine compartment on the car. The car itself was running reasonably well before this work but there were definitely some things that needed addressing as long as I was in there. As background, here’s a list of what I’ve done to the car in the past month:

- Remove the distributor and have it rebuilt by Jeff at Advanced Distributor
- Remove, clean and rebuild the carbs. Didn’t rebush them but all other seals were replaced. The existing needles were also reused.
- Remove/repaint the brake master and servo
- Remove and clean the clutch master
- Remove and clean the alternator
- Remove, sandblast and paint the exhaust manifold
- Remove and sandblast the intake manifold
- Remove the starter and have it professionally rebuilt
- Repaint various parts of the engine compartment where 15 years of summer use had taken its toll
- Clean and polish everything I could get to
- Put it all back together with new seals and fasteners wherever necessary
- Set the timing statically using a voltmeter to detect when the points open on cylinder 1 as per the manual

Thing is, not the car doesn’t run at all anymore. With the choke out it fires right away when I turn the key but it only runs for 1-2 seconds before dying. I managed to get it to run for 5 seconds once by gingerly tapping the accelerator but that was a fluke. It seems like it catches, starts to come up to speed on its own and then dies every time.

My assumption, given that it catches at all, is that the problem is in the fuel system, not the ignition system. Last night I pulled the carbs and went through them again checking that all ports are clear, the diaphragms are seated properly, the needle valve is working, float height is correct, float chamber vent mechanism is working fine. In short I can find nothing wrong with the carbs.

Looking for any ideas on what to look for next as I’m fresh out of ideas. I’m going to block off vacuum the hose to the brake servo just to make sure I don’t have a massive air leak there but, again, it was running fine before I “fixed” it so I doubt that’ll be the problem. I really didn’t change much, mostly I cleaned, painted and resealed things so I’m really stuck trying to figure out what I messed up.

 

[Bob_TR6]

Ballast resistance wire in place and OK?

 

[Mickey Richaud]

Hi, Phil, and welcome to the BCF.

Sure sounds like you've covered all the bases. I would double-check fuel delivery and insure that there's no vacuum leak anywhere.

Are the carbs ZS's? Are the diaphragms OK?

Hopefully, this'll get sorted out. Come on, guys, jump in here!


Mickey

 

[Andrew Mace]

Ballast resistance wire in place and OK?

Just a wild guess here on my part, but Bob might be onto something. Could it be that there's something amiss in the circuit to the coil -- where the ballast resistor comes into play providing higher voltage for the start but then something in that circuit is cutting out completely rather than "reverting" to the normal coil circuit? Possibly even as simple as a problem with the ignition switch and/or circuit?

Like I said, just a guess.... :confuse:

 

[Phil73]

OK, spent the last 2 days focusing on the fuel system on the assumption that the problem was there. I plan to verify that the fuel system is delivering fuel at a good rate tonight but, again, I'd be surprised if that was an issue since I didn't mess with the filter or pump while "fixing" the car. Double checked the diaphragms last night and they seem fine.

On the ignition side I'm less well informed about how that operates on startup. I've double and triple checked the order of the ignition wires (which are brand new) and the dizzy itself is freshly rebuilt with new points, condenser, etc installed as part of the rebuild. I have a low tension wire (white/yellow) going to the coil and a low tension wire going from the coil to the dizzy both of those seem to be in fine shape but I'll double check.

Wiring diagrams for a 73 show a ballast wire also going to the coil but my car has no such wire. Pics from before I started work this spring show that there was only 1 incoming wire and one wire from the coil to the dizzy before I started work.

Not real clear on how the ignition system differs on startup from normal running so maybe I need a tutorial

 

[TR3driver]

That would be my first thought as well. The point is that, while the starter solenoid is energized, the coil gets power through the white/yellow wire from the solenoid. Once the solenoid releases, the circuit through the ignition switch and pink/white resistor wire is supposed to take over.

A "quick and dirty" test is to temporarily install a jumper wire from a convenient power source (eg battery hot terminal) directly to the "+" terminal on the coil; then try to start the engine. If it now keeps running, that proves the problem is the ballast or switch, etc. Don't forget, you'll need to remove the jumper to stop the engine!

 

[jtcurtis]

Hi Phil,
I am here with very similar problem. Mine will kick over for a second, but as soon as I release the key to go back to the run possition the engine dies. The other night on the way home it gave me trouble too. I was on the highway and the ignition light came on and the engine just started to stall out. No power as I hit the gas, the engine was turning over because the clutch was engaged and I slowly pulled over to the side of the road. Before I came to a stop, I pushed in the clutch and tried to turn it over. It started right back up and I drove it home with out another issue. Now, the next day it doesn't start. It kicks over but won't stay running.
I am getting gas to the carbs and I think the carbs are working fine as they have been rebuilt about a year ago. I have the Crane Cams XR700 ignition system and coil. This has never given me a problem before. I think spark and fuel is good. Could my ignition switch be the problem? Have you considered that with your car?

Thanks for help,

Jeff

 

[jtcurtis]

Possibly even as simple as a problem with the ignition switch and/or circuit?

I was think my issue is the ingnition switch. How do I by-pass it to figure it out? Any suggestions? My manual suggests it as a possible problem too and it says to by-pass it, but I'm not sure how.

Thanks

 

[Bob_TR6]

Phil:
what's the other end of your WY wire connected to? If it's the starter (solenoid), then you do need another wire connecting the coil to a source of power when the starter isn't energized. You can check for power to the coil when the key is on, and the car isn't running (from the terminal with the WY wire on it to ground). Should be some 'reduced' value (9 volts? I forget). The purpose of this is that the coil is wound to provide a 'normal' spark at the reduce voltage supplied via the resistor wire during running, but a 'hotter' spark while cranking--to aid in starting.

You can wire around the ignition switch, as noted above, to check the resistance wire--but only for a short period of time. The coil (if stock) doesn't care for 12V for very long. Just provide 12 V from any source you have--I used to use a alligator clipped jumper right from the 12v+ of the battery. Just remember that to turn it off, you have to disconnect the wire.

 

[Andrew Mace]

Just for reference, here's a very good wiring diagram (scroll down to page 5 for the 1973 TR6 diagram).

 

[Phil73]

Not sure where the WY goes, I'll check that tonight but I'm, betting it goes to the solenoid. If so then that begs the question of how the car ever ran before. The solenoid was replaced as part of the rebuild and the connections to the new solenoid seemed a bit different. Any chance the old solenoid somehow allowed power to the coil even when the starter was not energized but now this new solenoid doesn't?

I can certainly verify all this once I get home from work and back out in the garage.

 

[tomgt6]

I noticed you did the distributor. An issue I had was the distributor was 180 degrees off. When the PO took the distributor out they put it back together 180 degrees off. That will keep a car from starting.

Another issue was the wire to the condenser wasn't connect correctly and was to stiff so every time the ignition timing moved it would come unseated in the distributor.

 

[TR3driver]

I was think my issue is the ingnition switch. How do I by-pass it to figure it out? Any suggestions?

On a 71 (which has no ballast nor wire to the starter solenoid), the "quick and dirty" test I gave above will effectively bypass the switch and wiring around the switch.

To bypass just the switch itself, you'll need to connect a jumper between the brown and white wires at the switch.

 

[Brosky]

Welcome to the forum, Phil (and Jeff).

If the dizzy came back from at Advanced, the condenser was placed properly. I'd look at the timing issue of being out 180 and fuel.

I haven't seen where you've confirmed fuel delivery while cranking, or that the fuel filter was replaced. Also make sure the rubber hoses are not crimped or collapsing under suction from the pump.

Fuel pumps are easy to rebuild. Here is my site page for just that: TR6 Fuel Pump Rebuild

 

[Phil73]

OK, problem solved (mostly). I got home tonight and before I even went in the house I went into the garage, hooked my multimeter from the + battery terminal to the + side of the coil, switched on the ignition and got no reading. Turned the key to start and got a 12 volt reading. Back to On...no reading.

I put the carbs back on, hooked up fuel, hoses, etc and tried to run a jumper from the battery to the coil. Soon as I tried that the starter itself kicked in and tried to melt the tiny little wire that I was using for a jumper. Hmmm...that's mighty odd I thought. Looked at the wire on the coil and it was WY. Looked at the wire on the starter solenoid and, as expected, it was WT and attached to the third terminal but in looking at the third terminal, it was also a direct connect to the main connector for the starter. That can't be right at all! Disconnected WY completely, hooked up my temp jumper from the bat to the coil, cranked it over and it fired right up. Idled smoothly at 800 even with the choke in and cold. Sweetest sound I’ve heard all week.

My car has no ballast wire and is running a Lucas Sport coil which is rated for use on non-ballast ignition systems. So, now the question is what I should do to remedy the problem. Clearly the old solenoid was wired differently than this new and questionable one that got installed when I had the starter rebuilt. I could order a “real” solenoid from TRF and install it. That’s definitely where my last one came from because I installed it myself. Other option would be to bypass the WY wire altogether and just hook something straight from the fuse box but that seems a little “hacky”.

I pretty grumpy with the place that rebuilt my starter but that’s neither here nor there.

Any opinions?

Thanks to all for the quick response. Bob_TR6 you jumped right to the answer and get credit for allowing me to sleep peacefully tonight 

 

[jtcurtis]

Welcome to the forum, Phil (and Jeff).

If the dizzy came back from at Advanced, the condenser was placed properly. I'd look at the timing issue of being out 180 and fuel.

I haven't seen where you've confirmed fuel delivery while cranking, or that the fuel filter was replaced. Also make sure the rubber hoses are not crimped or collapsing under suction from the pump.

Fuel pumps are easy to rebuild. Here is my site page for just that: TR6 Fuel Pump Rebuild

I can smell the fuel at the carbs as I almost flooded the engine trying to get it to stay running. I have not done any maintenance lately so I don't suspect the Crane Cams XR700 ignition system that was installed when I bought the car in Sept.
I had about three occasions where the engine cut off for a second and then started running fine while driving down the road. The engine cutting off was so brief the first time it occurred I thought I had just accidentally lifted my foot off the excellerator. But the other night driving home the engine cut off completely and when I tried to start it again, it kicked over right away and I drove it home and parked it.
This all leads me to believe that something is loose or something to that effect. I haven't tried to jumper the coil or by-pass the switch. But I'll try that tomorrow.
Thanks so much for all you guys helping. I'll keep you posted.

Jeff

 

[jtcurtis]

I was think my issue is the ingnition switch. How do I by-pass it to figure it out? Any suggestions?

On a 71 (which has no ballast nor wire to the starter solenoid), the "quick and dirty" test I gave above will effectively bypass the switch and wiring around the switch.

To bypass just the switch itself, you'll need to connect a jumper between the brown and white wires at the switch.

Thanks for the help. I am hopeful this will determine the problem. I'll keep you all posted.
Thanks so much,
Jeff

 

[TR3driver]

I have not done any maintenance lately so I don't suspect the Crane Cams XR700 ignition system that was installed when I bought the car in Sept.

OTOH, your description matches almost exactly what I had when the ground connection for my Crane XR3000 module got a bit loose and corroded. Went for several weeks where it would just miss a beat or two, and then pick up again. Of course it picked a cold, rainy night to start running much worse and eventually die altogether.

Tightening the screw got me home, but then I added the lockwasher and silicone grease it should have had to begin with and never had the problem again.

 

[tdskip]

Sure sounds, as the guys have suggested, electrical Phil.

Welcome to BCF by the way!

 

[tdskip]

Jeff - what year is your TR6. 1974 by chance?