I need some bright ideas

PostPost by: Mohe » Tue Feb 07, 2006 9:50 pm

I have a problem with my recently rebuilt Elan. Nothing new there I guess.

At first the car started easily and ran fairly well although there was a misfire on number 4. A crypton tune didn't really solve the problem and the dizzy has been back to Aldon for a check and they say it is fine.

Then the starter motor started to jam occassionally and this got more frequent. Eventually (the car has only travelled 50 miles) spinning the starter started to sound bad with a grating noise and this got worse. The engine occassionally lurches whilst the starter turns it over slowly even on jump leads. I cleaned the starter but it made no difference. I replaced the starter with a new 10 teeth, 3 bolt version and the first time I turned the key it sounded fine. It quickly started to graunch and turn over roughly and slowly.

I removed the plugs and tried the starter again. With no compression to fight the engine turns over well and smoothly on the starter motor and the oil pressure looks good - 40 psi on the starter motor sounds good to me.

All 4 pistons seem to be going up and down and in any case I drove the car into my garage with only the slight misfire. I find it hard to believe anything major like a rod or piston has broken.

I inspected the teeth on the starter ring by slowly turning the engine over with a spanner whilst watching the flywheel turn from underneath and I can see no obvious teeth missing or chewed up areas although I don't really know what to look for here.

I am at a loss to know what to do next.

Any ideas from you experts? I don't know where to go next.
:?:


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PostPost by: John Larkin » Tue Feb 07, 2006 10:09 pm

My Elan used to eat starter motor Bendix gears, until I discovered that the wrong flywheel ring gear had been fitted. I seem to remember that my car had a ring gear with 109 teeth and it should have been 111 teeth (or vice versa) --- thirty two years ago after all! The wrong ring gear was a Ford item that was commonly fitted by mistake during engine rebuilds.
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PostPost by: 1964 S1 » Tue Feb 07, 2006 10:12 pm

I'm definetly no expert but my S1 jumped a tooth on the timing chain once and exhibited some of the traits you write about. It still ran "okay" but with rough idle. It was a trick to start, with some of that lurching, and starter probs due I guess to erratic fire and valve sequencing. It's a freebee easy check to see if this could be your problem. Keep us posted.
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PostPost by: ppnelan » Tue Feb 07, 2006 10:24 pm

'Expert'? No. 'Experienced' with starter motor problems? Yes!

I would question whether the starter problem & misfire are related.

Starter:
If the bolts holding on the starter motor come loose, it can jump teeth & make awful noises. Eventually, the mounting plates crack & fall apart.

Do you have a new clutch cover? Check it is not too large a diameter on the outside edge, as this can foul on the starter bendix, pushing it out of engagement (if it manages to get into engagement, that is). I bought a 'new' one from an autojumble which was the correct type, but had not been 'ground down' like the original one I removed (as I later discovered...). I had it balanced & fitted it with a rebuilt engine, only to find that the starter bendix would not slide far enough into engagement! Rather than change the clutch, I turned down the body of the bendix and it has been fine.

There are many different starter motors, which all look the same but differ in detail. There is a 'tube' on the shaft that protrudes from the bush in the mounting plate. This provides a stop for the bendix gear and limits its maximum axial travel. Some of them are longer than others, and they can stop the bendix reaching the ring gear if they are too long. Check the marks on the bendix gear to see how far it is engaging with the ring gear teeth.

Was the engine rebuilt correctly, in terms of putting the right thrust washers between crank & block? If not, the crank may be able to slide slightly fore/aft & affect the starter engagement...? Unlikely, I know, but possible!!

Misfire
Is there a reliable spark at the plug? [I have just bought one of those 'spark plug lead testers' to avoid having to use a timing light to check for a spark.] If not, change plug, lead(s), distributor cap, etc. to make sure none of those are at fault.

If it's not ignition, it could be valves/timing or carburation. Could a bent valve (from mistake during engine rebuild) cause a misfire? Check the compression to make sure it is similar to the other cylinders & within spec.

I'll leave it the others to suggest other (more likely!) ideas....

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PostPost by: M100 » Tue Feb 07, 2006 11:00 pm

Has the flywheel been bolted on tight? Had a similar problem on another Lotus I bought. Rebuilt a spare engine and then found the fault within 5 seconds of dropping the gearbox off the old supposedly knackered engine.
Got me a good spare engine for 100 quid though!
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PostPost by: Mohe » Wed Feb 08, 2006 8:25 pm

Thanks you all for your thoughts. I guess this all means that I need to lift the engine out to check the starter ring/clutch/starter engagement which I think is only possible with the engine on a stand.

As I plan to use a friend's working garage/lift/hoist for this job I had better prepare as I can't leave the car in bits in his workshop for long. It will damage his business.

I believe there are 2 types of flywheels - 4 bolt and 6 bolt - and I guess you cannot tell which you have until the engine is out. Is that right?

If true I think it makes sense to purchase a starter ring before stripping the car down. Any suggestions for a source of starter ring please?

Thank you again

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PostPost by: ppnelan » Wed Feb 08, 2006 8:40 pm

Geoff,

My 5-speed +2 has the domed steel cover missing from the bellhousing, so I can see/feel the engagement of the bendix gear and ring gear with the engine in place. It may be possible to remove this from your bellhousing - I think they are only a press fit? Not sure whether you could get it back on again though - anyone tried it?

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PostPost by: rgh0 » Thu Feb 09, 2006 9:24 am

My 5 speed also has the cover missing. I always wondered if Lotus fitted them when they made the alloy bell housings for the 5 speeds. On the 4 speed its a press in fit and should be removable in place.

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PostPost by: type26owner » Thu Feb 09, 2006 9:02 pm

Geoff,
How do you know #4 is misfiring?

Best advice I can give you is to give up on the Lucas starter. You'll never fix it's problems, there are so many....like the Bendix nut breaking and jamming the unit into the ringgear with enough force to bend the lightened steel flywheel on my BRM. Grrrrr, those memories are still painful. :evil: Move on to another type of better starter like most of us have done already. Give up on the evil Lucas one. :wink:
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PostPost by: pereirac » Fri Feb 10, 2006 12:26 am

My 4 speed sprint also had the cover 'missing'. I never even reasied there was a cover until I saw one on ebay last year. Perhaps this was a factory 'option'... :D
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PostPost by: twincamman » Fri Feb 10, 2006 3:10 am

ok here we go -------carburettor is French for ' leave it alone' -- set the points --set the static timing --add new plugs correctly gapped -set the dwell AND THEN turn the idle jets [on top ] 1 and 1/4 turns from closed --[out ]when warmed up --and- then leave it alone -solve one problem at a time --your starter problem may be as simple as loose bolts or the wrong starter ------ -ed :roll: ---
Last edited by twincamman on Sat Feb 11, 2006 3:10 pm, edited 2 times in total.
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PostPost by: TypeRboy » Sat Feb 11, 2006 6:26 am

Just an idea or two from across the pond.. if the starter housing is pressed up against anything, like the chassis or something caught between it and the block then it won't sit straight where it bolts up. It takes very little side pressure to mess up the alignment.

If you are using the non-pre engagement starter, then don't spend any more time on it. At least get a pre engaged starter, or better yet one of the super starters ( usually just a gear reduction nissan starter with an adapter )

Do a compression test on your motor before you pull it all apart.. That will tell you it's basic health anyway. Also when it's running spray Wd-40 into each cyl and listen for increase or decrease in rpm. If you get an increase, you can be sure your problem is fuel or spark, not mechanical. Extra fuel may allow a weak spark to fire better, or give you a better a/f ratio if you are lean, but it won't help if a valve is bent or the cam timing is off.

Speaking of valve timing, it's a good idea to degree ( index ) the cams. the gears can be very inaccurate.

You never said if you swapped out the plugs or not. That would be my first step. My motor eats plugs, and the first signes are hard to start then gradually a sudden misfire that won't go away.
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PostPost by: Mohe » Wed Sep 15, 2010 8:37 pm

Geoff,

I too had a battle with very similar problems. Do remember that the Ford style starter motor engages with the starter ring teeth from the gearbox side hence the suggestions of watching what it happening from the gearbox side of the flywheel.

I switched to a Japanese manufactured and modified starter motor. This engages with the engine side of the starter ring, is geared and the car starts reliably and brilliantly. I'm also told a starter ring needs heating in an oven before fitting onto a flywheel although I have never done this myself.

My car was one tooth out on the timing chain and it ticked over roughly, was a little down on power, started badly and one plug fouled up quickly.

I hope this helps. Good luck.

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PostPost by: AHM » Wed Sep 15, 2010 9:58 pm

Do you have a good engine earth? if not the starter will run fine off load and poorly on load.

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PostPost by: gjz30075 » Thu Sep 16, 2010 3:04 pm

This thread is over three years old. Hopefully the problem is fixed by now..
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