Starting the engine for the first time

[Graham Baggaley]

It’s come to the point in the long rebuild that the engine (should) be ready to start.  It will not. I really feel like throwing the towel in.  
The engine has been rebuilt. All new ancillary parts. Car converted to negative earth, electronic ignition. 
With the plugs out the engine spins freely on the hi torque starter motor and there is very good and even compression. 
There is spark at the plugs. There is fuel at the carb. 
The distributor was inserted so that the number one cylinder would have the spark sent to it at TDC (I checked it was TDC by feeling the air pressed out of the plug hole and by knowing the cylinder was at the top by feeling it with a plastic straw. 
All sounds like it’s going to plan…wrong. 
I put the plugs in and now the car engine will not spin freely. It is labouring almost as if the battery is flat…which it is not. I even topped up the battery just in case. It’s also a very beefy battery with a start up power of 800A. 
What on earth have I done wrong? 
Im so close to getting the old girl back on the road but can’t see the woods for the trees here. What on earth have I done wrong? Any knowledge or inspiration is very welcome indeed  

thanks as always 

Graham

[Lebro]

I would start by checking the battery voltage while it is trying to turn the engine over (spark plugs in) if better than say 10 volts, I would then check the voltage (while turning over) on the starter motor it's self, you may find you are loosing volts through a bad connection somewhere. Prime candidates would be earthing engine to chassis, & battery to chassis.

Bob

Edited June 5, 2023 by Lebro

[Graham Baggaley]

1 hour ago, Lebro said:

I would start by checking the battery voltage while it is trying to turn the engine over (spark plugs in) if better than say 10 volts, I would then check the voltage (while turning over) on the starter motor it's self, you may find you are loosing volts through a bad connection somewhere. Prime candidates would be earthing engine to chassis, & battery to chassis.

Bob

I was suspecting a bad earth owing to the body and chassis all being repainted. 
I attached a pair of jump leads both to the battery earth and clipped them onto either side of the engine…still it stutters. 
the battery fluctuates on the starter (with plugs in) between 9.8v and 10.4v. The battery sits at 12.6v when nothing is being used. Battery is brand new. 
still no closer but thank you. Perhaps I will attach jump leads from my modern car to keep the voltage high. 

[stuart]

Sounds like lead to starter motor or starter solenoid itself, is it an original starter or a hi torque one?

Stuart.

[Graham Baggaley]

2 hours ago, Lebro said:

I would start by checking the battery voltage while it is trying to turn the engine over (spark plugs in) if better than say 10 volts, I would then check the voltage (while turning over) on the starter motor it's self, you may find you are loosing volts through a bad connection somewhere. Prime candidates would be earthing engine to chassis, & battery to chassis.

Bob

I was suspecting a bad earth owing to the body and chassis all being repainted. 
I attached a pair of jump leads both to the battery earth and clipped them onto either side of the engine…still it stutters. 
the battery fluctuates on the starter (with plugs in) between 9.8v and 10.4v. The battery sits at 12.6v when nothing is being used. Battery is brand new. 
still no closer but thank you. Perhaps I will attach jump leads from my modern car to keep the voltage high.

…to Stuart, it’s a high torque starter, new solenoid (though there is a solenoid in the starter as well), and all the cabling is new. 

[RobH]

There sound to be two issues here. One the engine cranks over slowly and two it doesn't start.  The only non battery-or-wiring thing I can think of that might cause both is very over-advanced ignition. 

Are you certain you have got the timing correct?  Are you sure you fitted the HT leads in the correct firing order? 

Final thought is that the four-pot can be reluctant to start when cold unless you have the choke fully engaged. 

 

 

Edited June 5, 2023 by RobH

[Lebro]

Good battery + geared starter motor I would expect to spin over quite briskly. Have you measured the volts on the starter directly when cranking, there could be high (relatively) resistance in the "live" feed to it.

Bob

Edited June 5, 2023 by Lebro

[Graham Baggaley]

Rob H. I suspect I could have completely messed up the timing. 
will check the firing order too. 

[markaluge]

Graham, best of luck with the starting. I know how nerve wracking this phase is. I started my TR3A for the first time in over 4 years last week. There was a spark at the plugs but it looked weak. I cleaned up the points, but that made no difference. Changed the coil, again no improvement in the spark. Changed the plugs and hey presto, good spark. How did all 4 plugs fail at the same time; I have no idea. 

I was then set to tackle fuel to the carbs, but thought I would have a go, and she started on the button; I couldn’t believe it. Now to see if I can get them tuned. 

Mark

[Trumpy3]

Graham

It does leave you a bit down after all the work and against your expectations.

All I can offer is check the timing as suggested and when checking the voltage at the starter, check it on both sides of the starter motors solenoid. If it is a previously used starter, then burnt contacts could well be the problem. it is a known problem that burnt contacts will/can cause the stater not to turn at all or turn slowly. It may have worked fine before the refit but more power will be needed after the refit. New contacts are cheep and easily obtained.

Brian

[Graham Baggaley]

Thanks all. 
it appears to be a timing issue. 
The first problem was that the mechanical advance was fully retarded. That sorted. The next problem appears to be that the electronic ignition is constantly in the open position. 
think I’m going to buy points and a condenser and see if throwing them in makes any difference 

[james christie]

At least with points (and condenser) you can more or less see and/or measure what’s going on. That said, I’m an electronic ignition convert and find my system (Pertronix) reliable and more important, precise. 
BUT, I always carry a spare!!

james

Edited June 6, 2023 by james christie

[Graham Baggaley]

So the problem is definitely with the electronic ignition. 
with the HT lead from the coil to the dizzy removed (and plugs still in) the engine spins just fine. As soon as the lead is put back in place the car stuttters, I suspect it is constantly firing the plunge rather than timed sparks. 
very annoying for sure. I can’t even drop in points and condenser as the base plate in the dizzy doesn’t have a pedestal to hinge the points from. 

[RobH]

Talk to the Distributor Doctor - he can probably supply a correct baseplate ready populated with points and condenser. 

[stuart]

1 hour ago, RobH said:

Talk to the Distributor Doctor - he can probably supply a correct baseplate ready populated with points and condenser. 

Yes as Ive sourced a few as emergency kits for electronic ignition equipped cars for touring. Best set up with pre gapped points too so literally 2 minute change over.

Stuart.

[Graham Baggaley]

2 hours ago, RobH said:

Talk to the Distributor Doctor - he can probably supply a correct baseplate ready populated with points and condenser. 

That’s exactly what I did. 
I ordered a new dizzy from him. Hopefully I’ll be on the road by the weekend. Fingers crossed. 

[Graham Baggaley]

On 6/7/2023 at 12:38 PM, Graham Baggaley said:

That’s exactly what I did. 
I ordered a new dizzy from him. Hopefully I’ll be on the road by the weekend. Fingers crossed. 

New distributor on. Five mins later the engine roared into life!

[brenda]

That’s brilliant news, can you now get out and put some miles on the clock.

Mike redrose group 

[Graham Baggaley]

On 6/11/2023 at 10:21 PM, brenda said:

That’s brilliant news, can you now get out and put some miles on the clock.

Mike redrose group 

I wish I could. Too many other things to make right