A problem getting the engine to simply turn over.
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Hi
My name's not Dan but I am desperate!
For around 4 years or so I've had a problem starting a sprint from cold. The problem is one of reluctance to turn over if left for a few days. Fortunately it's always easily fired up even on a slow turn of the starter I know I should have gotten to grips with it before now but during that time it was very much a case of using it when in the mood so I lived with its "foibles".
Having recently bitten the bullet I went thru everything obvious-
Every electrical connection such as both battery clamps, actual battery posts, feed to solenoid, feed from solenoid to starter, engine to chassis earths (I've two of them, one from the block to the front left tower plus the std one adjacent to the engine mounting), battery earth to chassis (this is bolted to the rear tower not to the floor/chassis mount in the boot).
All connections have been taken to bright metal and protected with vaseline.
Replaced the solenoid with new
Had the starter overhauled (it didn't need it as it turned out)
Car runs on an alternator (18ACR) and the starting fault was present before I fitted it.
Fanbelt is tensioned ok
Giving up I resorted to a call-out electrician who confirmed the charging rate was fine, there was no voltage "leakage" and the battery (Varta/6 months old) was holding its charge.
He suggested two things- possibly the modified engine earth to the front chassis tower was too small in diameter and might be giving a highish resistance so he advised reinstating the original which I've since done and (possibly) the feed from battery to solenoid might have developed a high resistance (I've not replaced this yet but am about to).
The engine is std Sprint tune, I've had the car since 1978 and it hadn't been altered in any way before by the first owner so no home bodges to look for. The ignition timing is definitely 12 degrees advance and the valve timing is exact. Mileage since a full engine overhaul is around 12000 or so and compressions are around 225 each- highish I know but figures are correct- immediately following the rebuild they were around 160 and since I'm always careful about running in they rose each time I re-tested them until peaking at the current figures.
It was never a poor starter in the past but then again the engine had never been overhauled before so who knows! I can't believe the engine is still tight as it seems easy enough to turn over by hand and seems to offer the same feeling of resistance as other elan engines I've used as a comparison.
Any ideas from fellow sufferers- I thought the compressions just might be the problem but can't be sure since other owners have reported similar figures without mentioning starting issues.
Thanks in anticipation
John
My name's not Dan but I am desperate!
For around 4 years or so I've had a problem starting a sprint from cold. The problem is one of reluctance to turn over if left for a few days. Fortunately it's always easily fired up even on a slow turn of the starter I know I should have gotten to grips with it before now but during that time it was very much a case of using it when in the mood so I lived with its "foibles".
Having recently bitten the bullet I went thru everything obvious-
Every electrical connection such as both battery clamps, actual battery posts, feed to solenoid, feed from solenoid to starter, engine to chassis earths (I've two of them, one from the block to the front left tower plus the std one adjacent to the engine mounting), battery earth to chassis (this is bolted to the rear tower not to the floor/chassis mount in the boot).
All connections have been taken to bright metal and protected with vaseline.
Replaced the solenoid with new
Had the starter overhauled (it didn't need it as it turned out)
Car runs on an alternator (18ACR) and the starting fault was present before I fitted it.
Fanbelt is tensioned ok
Giving up I resorted to a call-out electrician who confirmed the charging rate was fine, there was no voltage "leakage" and the battery (Varta/6 months old) was holding its charge.
He suggested two things- possibly the modified engine earth to the front chassis tower was too small in diameter and might be giving a highish resistance so he advised reinstating the original which I've since done and (possibly) the feed from battery to solenoid might have developed a high resistance (I've not replaced this yet but am about to).
The engine is std Sprint tune, I've had the car since 1978 and it hadn't been altered in any way before by the first owner so no home bodges to look for. The ignition timing is definitely 12 degrees advance and the valve timing is exact. Mileage since a full engine overhaul is around 12000 or so and compressions are around 225 each- highish I know but figures are correct- immediately following the rebuild they were around 160 and since I'm always careful about running in they rose each time I re-tested them until peaking at the current figures.
It was never a poor starter in the past but then again the engine had never been overhauled before so who knows! I can't believe the engine is still tight as it seems easy enough to turn over by hand and seems to offer the same feeling of resistance as other elan engines I've used as a comparison.
Any ideas from fellow sufferers- I thought the compressions just might be the problem but can't be sure since other owners have reported similar figures without mentioning starting issues.
Thanks in anticipation
John
- worzel
- Fourth Gear
- Posts: 611
- Joined: 13 Jan 2004
I had the similar problem with my S2, sometimes it spun fast and the next try it was very slow, the problems started after I had re done the engine to higher spec, I also suspected a high CR and general tightness and lived with it for a few years...also did all the connections, new battery, extra earth's etc.
One day I decided to replace the main feed from battery to solenoid even though it was not that old (had been renewed about 5 or 6 years earlier)
I had one made up and fitted it, now it is 95% better with just a very occasional slow starter speed....so its good enough for me, I have more important things to think about!
(ps I'm sure you have checked the small earth to the solenoid mounting but just in case...)
One day I decided to replace the main feed from battery to solenoid even though it was not that old (had been renewed about 5 or 6 years earlier)
I had one made up and fitted it, now it is 95% better with just a very occasional slow starter speed....so its good enough for me, I have more important things to think about!
(ps I'm sure you have checked the small earth to the solenoid mounting but just in case...)
Brian
64 S2 Roadster
72 Sprint FHC
64 S2 Roadster
72 Sprint FHC
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types26/36 - Coveted Fifth Gear
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How about a quick check with some battery jumper cables? From the battery, one to the solenoid and the other directly to the engine block. Should take care of any high resistance in the existing cables if it exists.
Rob Walker
26-4889
Rob Walker
26-4889
Rob Walker
26-4889
50-0315N
1964 Sabra GT
1964 Elva Mk4T Coupe (awaiting restoration)
1965 Ford Falcon Ranchero, 302,AOD,9",rack and pinion,disc,etc,etc,etc
1954 Nash Healey LeMans Coupe
Owning a Lotus will get you off the couch
26-4889
50-0315N
1964 Sabra GT
1964 Elva Mk4T Coupe (awaiting restoration)
1965 Ford Falcon Ranchero, 302,AOD,9",rack and pinion,disc,etc,etc,etc
1954 Nash Healey LeMans Coupe
Owning a Lotus will get you off the couch
- prezoom
- Coveted Fifth Gear
- Posts: 1196
- Joined: 16 Mar 2009
You can check all of the suspected high resistance contact points by bridging them with a multimeter while someone is cranking the engine, the display will show the volt drop across each of them.
Another thing to check is whether the static advance is opposing the cranking, disconnect the coil LT lead and see if it cranks over any quicker, this does usually manifest itself when the engine is hot and with maximum compression but can also do so when cold cranking.
Good luck
Another thing to check is whether the static advance is opposing the cranking, disconnect the coil LT lead and see if it cranks over any quicker, this does usually manifest itself when the engine is hot and with maximum compression but can also do so when cold cranking.
Good luck
- Chancer
- Coveted Fifth Gear
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- Joined: 20 Mar 2012
Chancer wrote:You can check all of the suspected high resistance contact points by bridging them with a multimeter while someone is cranking the engine, the display will show the volt drop across each of them.
Well I dont know about John but when I was having problems I did many checks,tests and variations of these tests and I would never get constant readings, sometimes they showed high resistances and sometimes no excessive resistance even though the starter would or would not operate....there was just no definitive answer!
The theory is fine but in practice ..........
Brian
64 S2 Roadster
72 Sprint FHC
64 S2 Roadster
72 Sprint FHC
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types26/36 - Coveted Fifth Gear
- Posts: 3404
- Joined: 11 Sep 2003
The fingertip used as a pyrometer is my most sensitive and reliable instrument and has never let me down, at low voltages like the volt drop across a resistance the multi-meter is best used as a comparator to check a suspect joint against the others.
The contact point of the probes can often give false readings the connections should really be done with strong alligator clamps on clean metal.
The contact point of the probes can often give false readings the connections should really be done with strong alligator clamps on clean metal.
- Chancer
- Coveted Fifth Gear
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- Joined: 20 Mar 2012
Hi
Checking the actual voltage at the starter during starting should tell if there is a problem anywhere on the supply and checking the temperature of connections can show up faults. An infra-red temperature sensor can be useful sometimes, although with repeated starter use the temperatures of poor connections can usually be sensed with your finger - although beware they are not too hot!
Assuming all is well with supplies and earths it may be with your high cylinder pressures you just need more torque at the starter. I seem to remember the works Twin Cam Escorts used 24V starters for reliable starting. A gear reduction starter may be the answer, I think I might try one when I get my S4 back on the road.
Good luck
Gray
Checking the actual voltage at the starter during starting should tell if there is a problem anywhere on the supply and checking the temperature of connections can show up faults. An infra-red temperature sensor can be useful sometimes, although with repeated starter use the temperatures of poor connections can usually be sensed with your finger - although beware they are not too hot!
Assuming all is well with supplies and earths it may be with your high cylinder pressures you just need more torque at the starter. I seem to remember the works Twin Cam Escorts used 24V starters for reliable starting. A gear reduction starter may be the answer, I think I might try one when I get my S4 back on the road.
Good luck
Gray
- Gray
- Second Gear
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- Joined: 27 Feb 2010
Another possibility could be a strange problem I had that I didn't realise could happen; the pinion [ on an original starter] was actually touching the edge of the clutch pressure plate when engaged. I checked a spare starter and another pressure plate and both showed heavy scuff marks. After hitting the pressure plate with a grinder when the engine was out the slow starting when cold was a lot better.
- AussieJohn
- Third Gear
- Posts: 440
- Joined: 10 Jun 2007
Hi
Thanks for all of the input. I've just replaced the feed from the battery to solenoid but haven't yet tried to start up- I'm going to leave it for a couple of days to replicate the earlier conditions since I only just ran the car on friday for about 30 miles to dust it off so presumably the battery will be fully charged after that.. I'll post the results of the next attempt at starting.
Regards and thanks to all
John
Thanks for all of the input. I've just replaced the feed from the battery to solenoid but haven't yet tried to start up- I'm going to leave it for a couple of days to replicate the earlier conditions since I only just ran the car on friday for about 30 miles to dust it off so presumably the battery will be fully charged after that.. I'll post the results of the next attempt at starting.
Regards and thanks to all
John
- worzel
- Fourth Gear
- Posts: 611
- Joined: 13 Jan 2004
Hi- again
Might be getting boring now!
Just reporting back in case others have similar problem(s). I've since replaced the battery cable to solenoid with a new one. Both ends soldered with new battery clamp and new solenoid ring terminal. Left the car standing for around a week- come to start and the problem is still there. Slow to turn over but fortunately catches quite easily after a few seconds.
A real mystery in view of attending to the usual "suspects". To recap I've checked the following-
Charging rate (fine)
Voltage/current leakage (none)
Starter (wasn't faulty but got it rebuilt anyway)
Ignition timing (usual 12 degrees)
Alternator output (fine)
Condition of battery terminal posts (cleaned down to bright lead)
Solenoid has been changed for new, all earths have been cleaned to bright metal, covered in vaseline etc. Engine now two earths.
I'm beginning to conclude that the high compressions have something to do with the problem- if I trickle charge the battery for a day or so regardless of outside temp ie even if below freezing and if car is left standing for a few weeks the engine spins very quickly as per normal. Turning over the engine by hand with the plugs in doesn't reveal anything noticeable- subjective I know but comparing the effort with a big valved plus two both require roughly the same effort from me. Compressions are around 225 each and I guarantee there's nothing wrong with the valve timing- it's to within a fraction of a degree. Engine is bog std tune sprint.
Help!- I admit I'm beaten
John
Might be getting boring now!
Just reporting back in case others have similar problem(s). I've since replaced the battery cable to solenoid with a new one. Both ends soldered with new battery clamp and new solenoid ring terminal. Left the car standing for around a week- come to start and the problem is still there. Slow to turn over but fortunately catches quite easily after a few seconds.
A real mystery in view of attending to the usual "suspects". To recap I've checked the following-
Charging rate (fine)
Voltage/current leakage (none)
Starter (wasn't faulty but got it rebuilt anyway)
Ignition timing (usual 12 degrees)
Alternator output (fine)
Condition of battery terminal posts (cleaned down to bright lead)
Solenoid has been changed for new, all earths have been cleaned to bright metal, covered in vaseline etc. Engine now two earths.
I'm beginning to conclude that the high compressions have something to do with the problem- if I trickle charge the battery for a day or so regardless of outside temp ie even if below freezing and if car is left standing for a few weeks the engine spins very quickly as per normal. Turning over the engine by hand with the plugs in doesn't reveal anything noticeable- subjective I know but comparing the effort with a big valved plus two both require roughly the same effort from me. Compressions are around 225 each and I guarantee there's nothing wrong with the valve timing- it's to within a fraction of a degree. Engine is bog std tune sprint.
Help!- I admit I'm beaten
John
- worzel
- Fourth Gear
- Posts: 611
- Joined: 13 Jan 2004
prezoom wrote:How about a quick check with some battery jumper cables? From the battery, one to the solenoid and the other directly to the engine block. Should take care of any high resistance in the existing cables if it exists.
Rob Walker
26-4889
Did you try doing this with good quality jumper cables?
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
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pharriso - Coveted Fifth Gear
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Have you tried cranking it with the ignition disconnected as per my posting?
A battery will always crank an engine much quicker after trickle charging because the plates will be warm and the internal resistance at a minimum.
If the above doesnt work replicate the cold cranking conditions and try pouring a kettle of hot water slowly over the battery, leave it a few minutes and it will crank easier, if its a sugnificant difference it might be worth a new battery.
What cross section of cable did you replace the old one with?
A battery will always crank an engine much quicker after trickle charging because the plates will be warm and the internal resistance at a minimum.
If the above doesnt work replicate the cold cranking conditions and try pouring a kettle of hot water slowly over the battery, leave it a few minutes and it will crank easier, if its a sugnificant difference it might be worth a new battery.
What cross section of cable did you replace the old one with?
- Chancer
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If you think that the high compression is a factor of slow turn over have you tried to try turning it over with the plugs out and with them just loosened slightly to see if that makes any difference. Disconnect the coil if you try the slightly loose plug test.
Chris.
Chris.
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tcsoar - Third Gear
- Posts: 305
- Joined: 01 May 2007
In my experience a reasonable battery and starter motor with cables and joints in good order will have no problem whipping over an engine with significantly more than 225psi hot compression without any ignition, however the spark occurring at 12 BTDC opposes the starter and tries its best to reverse the direction of rotation,
I urge the OP to try cranking without ignition, if it is this there are very easy ways to overcome it which galso ive you the benefit of an additional security device.
I first came across this with 6 volt electrics on Veedub campervans, timing the motor by ear gave much better performance, flexibility and fuel economy but the increased advance over standard (no idea how much it was, you dont measure things when you tune by ear) made starting an impossibility hence the search for a solution.
Think of Biggles and you will be on the right track
I urge the OP to try cranking without ignition, if it is this there are very easy ways to overcome it which galso ive you the benefit of an additional security device.
I first came across this with 6 volt electrics on Veedub campervans, timing the motor by ear gave much better performance, flexibility and fuel economy but the increased advance over standard (no idea how much it was, you dont measure things when you tune by ear) made starting an impossibility hence the search for a solution.
Think of Biggles and you will be on the right track
- Chancer
- Coveted Fifth Gear
- Posts: 1132
- Joined: 20 Mar 2012
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