First start after rebuild

[davidj]

Afternoon,

This afternoon I attempted to start my rebuilt engine. Unfortunately it did not go well. The starter would barely turn over the engine! I tried jumping it from my daily drive but little better. Removed the starter motor from my other elan which I know is good and still no better.

I guess the engine is very tight as it has been rebuilt. Any suggestions how I can I can get it turning faster? I could buy a new starter but I am reluctant to spend £250+ for a geared motor.

Thanks in advance for any suggestions.

[ericbushby]

Hi David,
Firstly it may not be a tight engine. How does it turn using a spanner on the crankshaft pulley.
Try a jump lead from the negative terminal of the battery to the engine block to eliminate weak chassis connections.
I am assuming negative earth.
Then try a jump lead from the battery positive to the solenoid.
What voltage are you getting at the motor when cranking? expect 8 or 9 volts.
You will have painted the engine while it was out. were the earth connections cleaned after painting.
That sort of thing.
Best of luck
Eric in Burnley
1967 S3

[pharriso]

Does it spin over at speed with the plugs out?

[davidj]

No. It does spin over slowly without the plugs but even slower/stops with them

[berni29]

Hi

Try all the very good suggestions above. I would not have the fuel connected up until I was happy that the engine is turning freely. You do not want to start it if it isn't.

Who rebuilt the engine? You or a shop? The likelihood is that you have an electrical issue as the engine would have been turned at every stage of building and any tightness/binding resolved.

Best of luck

Berni

[gjz30075]

It's possible two of the main caps or rod caps got reversed, ie, in the wrong location.

[mbell]

I'd probably have a go at priming the oil system via the pressure gauge take off. Unlikely the issue but good for piece of mind when turning it over knowing it had oil in the right places.

[512BB]

As above seen here, but I must admit I had never done this before inheriting this natty tool about 10 years ago. I used it to fill the oilways on a twincam that had not been started for 16 years.

David wrote 'It does spin over slowly without the plugs'

The chances are that your starter motor is duff, once you have elimanated all possible other electrical issues, including the battery.

Leslie

[2cams70]

I could start an argument about the necessity of pre-filling the oil ways on a Twin Cam but I won’t!

[davidj]

Thanks very much for your advice. I 'ave ordered another starter motor and will check all the earths again. I think they are ok as I was very careful to remove all the paint, but it will not do any harm checking again. In the dim and distant past I was starting another rebuilt engine and had a similar problem. In that case it was the starter but this time I know the starter is good as I took it off my +2!

When I was turning the engine over on one battery the voltage was below 12. When attempting to jump start, 12.5 ish.

The engine was built at great expense by a uk twin cam "expert" but he appears to have gone incommunicardo (or just not anwering my phone calls!)

Cheers,

David

[gjz30075]

Pull the plugs and try turning it over by hand via a 5/8" box end wrench on the crankshaft pulley bolt.
Should be fairly easy to turn. If not, there's something internal that's the problem.

[ericbushby]

Hi David,
If that 12 volt reading was at the battery then it seems high to me, suggesting a high resistance joint somewhere in the circuit limiting the current. I did some tests recently for another member and mine was about 10 volts at the battery when cranking.
If that voltage reading was at the motor as I asked, then I cannot understand how that could
be unless the motor was faulty and not drawing full current. and yet you have tried two motors!!
You will not get 12 volts at the battery when cranking an engine. 9 or 10 volts is more likely.
If two motors including a known good one have not solved it then another good motor will not either.
It might be worth fitting your suspect motor on your other car.
I still believe there is something else limiting the current in the circuit.
Take a voltage drop reading between the battery terminal and the other end of the cable. Chassis connections are :- negative terminal to engine block. Expect 1 to 1.5 volts.
Positive circuit volt drop is from positive terminal to solenoid or better to motor live terminal. expect 0.5 volts.
Also check battery terminals are clean.
If either of these readings is much higher then you have the problem surrounded and you can then close in on it.
Keep going,
Eric in Burnley
1967 S3SE DHC

[englishmaninwales]

I could start an argument about the necessity of pre-filling the oil ways on a Twin Cam but I won’t!

[Slowtus]

First follow the advice given about turning it by 'hand'.

You tried a starter, not knowing the condition and it performed poorly

You then tried a known good starter and it also performed poorly.

Before you go checking wires, grounds, volts, amps ohms and all the rest and buying anew starter - FIRST try turning it by hand, as suggested.

[davidj]

Sorry, should have responded to the suggestion. Yes, i have turned it by hand, not least when I was setting the timing. It turned over fine.

David