After 2 years of ownership, I was set Thrusday night to start the Elan for the first time. First, wasn’t getting any gas to the carbs. Found that it was due to defective check valves in fuel pump. Fortunately I had won a spare on Ebay for cheap and swapped them. (Is it possible to fix these? Seem’s like they’re pressed in and the housing is peened over to keep them in forever)
Then I tried to start. Now, I’ve rebuilt this engine to 10.5:1 compression. Without the sparkplugs in, it turns over quickly and builds 50psi oil pressure. However, put even one plug in and it get’s so bogged down on the compression stroke that it’s too slow and there’s no way it’ll go.
Hooked another battery up in parallel so I could double the amps at 12V. Better, but still nothing. Then, I held the clutch in, even better but still no go. By this time, batteries were dying.
So, I’ll charge the two batteries up and try with the clutch in and use a better pair of jumpers (believe me, jumper quality can make a huge difference) and try again when I get home next week.
Now, I know I’ll get tons of reply’s telling me to buy a gear reduction starter, and if it comes to that I will. However, with the first baby arriving in a few weeks, I’m not sure what I did with that bag of money I had earmarked for the Lotus…
Darren,
How tight is the engine if turned with a spanner on the front crank bolt? I presume it has been rebuilt, can it be turned by hand?
Something does not sound right with the quote “I held the clutch in”…if anything it sould be harder to turn with the clutch depressed…pressing the clutch is forcing the crankshaft forward against the thrust washers creating more resistance.
Sounds more like a high resistance in the starter/ battery cables/earth connections/jumper leads/ign switch etc.etc.
Thanks Brian. Perhaps the “better with the clutch in” was just my imagination and/or wishfull thinking at the end of the night. I can definitely turn the engine by hand with a spanner, very easily. Knowing about VD from other British cars (voltage drop, that is), I have run a large high strand cable from the battery right up to the solenoid and then to the starter. On the grounding side, I have run the main ground for the car from the battery right to the starter motor itself.
Your comment on the ignition switch is interesting. If there is not enough power going down to the solenoid from the starter switch for the signal, is it possible the coil is not fully closing the internal power switch and therefore only a fraction of the power is passing down to the starter?
Darren
In the starter motor are four carbon brushes,if one or two are too worn you’ll only have half power from the starter,or at least that was the problem with mine…
I had the same problem and actually managed to destroy a starter motor - oops. I was hooking up a battery using jump leads, and the connections were just not low enough resistance. I rigged up a proper set of cables and bolted them up securely, and it was fine. Incidentally, I did end up getting one of those gear reduction efforts. My engine was rebuilt with a compression ratio of 10.9 to one, and I was advised that the standard motor should be fine up to over that - can’t remember the figure. So you should be ok, and I would check out the wiring first.
Good luck - they do sound nice once they’re running…
Good battery, good cables, good sloenoid, good standard starter will start a twin cam with 13:1 compression OK. For how long it will do it and how reliably is the problem that drives people to modern preengage starters.
Proivded the starter is seeing good voltage at the starter terminals when trying to crank ( say 10 to 11 volts) and still not managing to spin the motor I would look for a replacement starter. Replacement standard starters are relatively cheap if money a challenge. The 3 bolt preengage starter from early 70’s Escorts also fits using just the 2 mounting holes and is what I use and also relatively cheap. It works with either a 9 tooth pinion to match the original Lotus one or the standard 10 tooth pinion that Ford used with a slightly diiferent flywheel. The special gear reduction starters are the final option but relatively expensive.
You rebuilt the engine… I assume it started fine before. Could you have accidently removed the ground from the engine to the frame? Could that ground wire have become damaged?
Thanks all for your suggestions. I bought the car in pieces, so it never started before. I cc’d the head and requested the piston specs in consultation with one of the usual suppliers, so I’m pretty sure the compression is accurate. I also dialed in the cam timing and put the appropriate offset dowels in to match the cam specs I got also from one of the usual suppliers.
You are right on the ignition timing advance. While you want it on a broken in engine to run properly, having it in my case will cause even more restrictions in turning it over.
I’m in Prague and can’t wait to get home and give it another crack!
there’s only so many times I can recommend getting one of these gear reduction jobs. These cars are getting to the $20-30,000 range when nice, so a $175 starter seems like it’s justified. I never looked back. you wont either when you spring for one.
I assume you have the original Bendix starter with the separate solenoid mounted on the fire wall. The solenoid can be the problem. I found a six volt drop in voltage accross the contacts when cranking with a relatively new Lucas one and switched to an American Ford one. Even the old Ford seven litre V-8s used Bendix staters and if they can take the current to start one of those, it has no problem with a 1.6 l TC.
Measure voltage drop + on battery to starter+ when cranking.
Measure voltage drop - on battery to - on starter when cranking.
The starter itself should see 11 volts or thereabouts across itself when cranking if you are seeing a big drop on one of the leads (cable)it is defective. Replace or repair defective lead( cable).
In fact this is the best way I have found to diagnose electrical problems in cars. The voltage 12v should drop across the device (motor, bulb, fan, etc) itself and not across the wires, switches, fuzes etc leading to it or returning from the device to the battery. Usually the voltage drop you will see across switches and the like will be on the order of .2v or less when you see more voltage you have a bad switch, connection, etc. You see more voltage drop in a starter circuit because it uses so many amps. So there 1v to maybe 2v is acceptable. You have to measure circuit when it is operating but you do not have to take anything apart. The beauty of this method is that you just replace or repair the defective part and you don’t have to replace alot of expensive parts hoping for a fix. I think we have all done that. Isn’t it fun! I admit I stole this from Tracy Martin’s book How to diagnose and repair automobile electrical systems. It is a gem.
Thanks to everyone for their suggestions. Turns out I had good voltage at the starter when I checked it, so took the starter off.
Inside there is a plastic piece where the two coil leads meet the main terminal. This had gotten hot and slightly melted, probably due to the fact I cranked on the engine too much/long previously to check my oil pressure etc.
So, I had a new piece of plastic turned up on a lathe, resoldered the leads together, and now the starter has more than enough power to turn the engine around.
I can only assume that thew melted plastic allowed the two coil wires to separate slightly and that they were arcing inside, which was cause of my voltage drop…
