Engine slow to turn over (post moved from Elan forum)

[oakleydad]

I have a 69 Elan +2 and the engine is very slow to turn over. I have jump started from a car with a running engine with about 13Volts measured on the solenoid, with a digital multimeter. When I try to start the engine the starter just about turns the engine over once then stops. The voltage on the starter motor side of the solenoid is about 6 volts when when the starter is engaged. Does this mean my solenoid is faulty? Any ideas greatly appreciated.

[EPA]

I'm not clear from your description if the engine started when you fitted jump leads or if the 13volts was also at the starter side of the solenoid. Also if it did start, where in the circuit did you connect the jump leads?
If you check the battery side of the solenoid it should have the same voltage as the starter side when the solenoid is activated, if this is not the case then you have a faulty solenoid , assuming you were connecting your meter to the solenoid terminals and not the cable lugs.
If the engine turned ok and started when you used the jump leads then you need to work back from the point you connected the leads to find the problem.
Assuming the battery is ok it's likely to be the battery connection to the chassis or the battery connections themselves.

Ed

[oakleydad]

Ed thanks for the reply, No the engine didn't start. I have checked all the relevant connections including the earths and they all appear OK. Is it possible to dismantle and repair the solenoid ?

[Sea Ranch]

Ones I've seen have their metal bodies pressed/crimped together in such a way as to make unable to be disassembled. You can "break" them apart, but not put them together again. At least the version on my car (don't have a pic handy). It's a safety thing. Don't want this component to goof up on you. Trust me. I once had a solenoid that had a very weird failure mode, right from new: it literally stayed engaged and my poor starter kept cranking for an ungodly period of time whilst I scrambled round back of the car, flew into the boot and disconnected the battery leads to make it all stop (removed and never reinstalled that solenoid!!).

Good news is they're reasonably cheap.

Agree with Ed. Did the testing show a drop in voltage from one terminal of the solenoid to the other, when the solenoid button was pushed? If so, yeah, the solenoid needs replacing. If not, keep looking.

Further, not to nitpick, but honestly, you can't tell much from looking at a high current electrical connection. It can "look" fine because you're not actually looking at the connecting/contact points. Need to remove/disassemble the connection, clean very well, then reassemble. Often a miraculous improvement awaits.


Randy

[john.p.clegg]

Taking the solenoid apart is easy-peasey,just drill out the rivets,clean the contacts ( burnish) and tap the holes and fit screws..

Maybe try the good battery and jump leads direct to the starter side of the solenoid and engine ( earth )...don't be afraid of a few sparks..

John

[Sea Ranch]

Taking the solenoid apart is easy-peasey, just drill out the rivets . . . don't be afraid of a few sparks . . . John

I love this guy!!

After all, it's only 12 volts!!

[john.p.clegg]

Maybe only 12 Volts but lots of Amps...

John

[PeterK]

Where are you in Hampshire. I'm near to Fleet on the M3 and have a spare solenoid you could try.
Peter

[PeterK]

Maybe only 12 Volts but lots of Amps...

John

Get it wrong and you'll have more Amps than you can shake a fire extinguisher at !

[EPA]

The direct connection to a battery is a risky method and you will get loads of arcing if you don't have good connections.The starter draws a large amount of current especially in cold weather when the oil is cold.
As mentioned previously, if you get a voltage variance across the two terminals when the solenoid is pressed, the solenoid must be faulty.
If you connect one lead of your meter to each of the solenoid terminals and press the solenoid you shouldn't get any reading at all.

Ed

[AHM]

I recently had exactly the same on both elans (last weekend) both rebuilt in the past 3 years all terminals greased. I read loads of stuff on this site - in summary

Remove, clean, and Vaseline every terminal and connection. Particularly the earth bolt in the boot, which is tightened in the bobbin, rather than the nut on top.

Check the resistance at each point. My meter reads 4 Ohms when I connect the 2 leads the worst I got after cleaning was on the starter lead 5 Ohms. (Use a jump lead to get from front to back)

I found a loose battery lead on the solenoid on one car and a bust solenoid on the other.

Battery - Look-up "equalisation charge on the internet." If you have a clever charger the battery probably isn't fully charged.

The S3 (dynamo) is back to starting well even though it is living outside at the moment. The new solenoid for the S4 arrived in the post this morning

[Chancer]

At the risk of uncomplicating things I would just stuff a hefty spanner or screwdriver across the terminals to rule out or prove the hypothesis of dirty solenoid contacts, after cleaning up all the battery, starter and earth connections that is.

Always worked for me and a lot of my spanners show signs or arcing

[AHM]

And you would have a warm spanner too!

[billwill]

At the risk of uncomplicating things I would just stuff a hefty spanner or screwdriver across the terminals to rule out or prove the hypothesis of dirty solenoid contacts, after cleaning up all the battery, starter and earth connections that is.

Always worked for me and a lot of my spanners show signs or arcing

Oh, don't do that, highly dangerous, You might drop it while very hot. Resistance of steel is higher than copper/aluminium so it will get hot.

If you want to try that test use a single starter jump lead instead. Clamp one croc clip to one of the fat terminals (the one that goes to the starter) and touch the other croc clip to the terminal where the fat lead from the battery is connected to the solenoid.

[Sea Ranch]

Everyone has a different tolerance for risk . . .

That's why our wives don't join in so readily with our hobby . . .

(Am I going to regret that comment?? )