Morris Minor Owners Club

Fingolfin wrote:Good thinking Katy; all I can say on vacuum is that I've sucked on the pipe, and the plate in the dizzy turned. For what that's worth.

The white is a reflection of high-intensity work lights on the polished surfaces of the intake manifold, to the left, and the carburetor, to the right. Between them is an induction heater (which isn't wired in), which is black, but serves to accentuate the brightness of the metal.

I think Katy meant a leak in the inlet manifold area causing a missfire/erratic run. Like the manifold to head gasket and the 2 carb to manifold gaskets

It is indeed hard to see, Katy, but it IS there. I ordered both the rear bracket and the front slidey bracket from ESM.

Hmm, the leak is plausible, but I think it unlikely now; I've tightened every bolt and nut, and while the engine was out I changed the manifold-to-head gasket and the manifold-to-carburetor ones. No change from doing so. For what it's worth, I also tightened the vacuum pipe fixing at the carburetor, and no change.

Oh! Could it possibly be a malfunction in the automatic advance system (not the vacuum, but the weights)?

As an aside, if you are on Facebook, you can go and "like" the new page http://www.facebook.com/MogAndFriends, which is dedicated to my two Morris Minors (including Stiltzkin), and then you will be able to see what's going on day-by-day. Excuse the shameless plug.

awesome progress
like it

Thanks Alex. A slight bit of progress -- I finally received Mog's spare tire! It's 145R14, made by Coker Tire in an old Firestone mold.[frame][/frame]Just need to have it mounted.
No word on when Mog will "see a doctor." But hopefully dad will take it to a mechanic soon.

Here's a detailed list of everything I know about the engine trouble, and everything I've tried (I think).

Engine trouble

Developed very suddenly ca. 13 December 2012.
Running very rough, such that engine is shaking hard against its mounts. Revs will not rise above 1700 and usually not above 500 without lots of persuasion. Depressing or releasing accelerator does not vary engine speed by any appreciable amount, nor does choking or increasing airflow (though holding accelerator down for long periods does very gradually increase engine speed). When engaging clutch, engine slows; when releasing clutch after engaging a gear, engine invariably dies, though it seems to just barely like reverse gear more than the forward gears.

Engine is smooth and easy to turn over by hand; with plugs in, compression stroke seems strong; with plugs out, turning is smooth and without hang-ups throughout revolutions. When turned by hand, engine makes no strange noises. Concluded from this that timing chain has not snapped or jumped a tooth.

Carburetor damper was sticking. Damper cleaned, needle and jet replaced, damper moves easily now; no change in engine running. Accelerator and choke cables readjusted; no change. Having air filter on or off makes no difference. Carburetor float does not stick and seems to be functioning correctly.

Fuel pump delivers plenty of fuel and fuel filter is new and unclogged. Tank has enough fuel in it (about ¼ tank at this writing).
Valve gaps were reset prior to trouble developing.

Static timing and points gap was reset when engine was pulled, ca. 20 December, and made no change. Turning distributor either way (advancing or retarding timing) makes very little change. Changed condenser 9 January 2013; no change (but replacement condenser condition was unknown). Distributor has not been removed for at least two years, and running was good prior to 13 December, so timing is not 180 deg out. Cap is in good shape and shows no tracking or cracks. Points had some slight burning/oiling, but cleaning and filing them made no difference. Resetting points gap to 15 thou made no difference. Changed points for a brand-new set 11 January, set to 15 thou; no difference.

Oil changed 8 January, after refitting engine. No change.

Sump removed 1 January for cleaning and inspection of engine innards. Sump had very little sludge and no metal shards. Crankshaft appeared in good condition with no cracks. Camshaft appeared in good condition as well, as did distributor drive.
Clutch pressure plate changed 5 January for an unrelated problem; prior to this, flywheel and engine backplate were removed for renewal of gasket. Oil pump was like new. Flywheel was refitted correctly and clutch was reassembled correctly.

Battery was recharged prior to trouble developing, and since, and this made no difference. Starter functions well with lots of power.

There are no indications of head gasket trouble.

Plug wires changed 10 January; no difference. Each wire sparks against its plug, though Cylinder 3 seems to be receiving a larger spark than the other cylinders.

Another compression test conducted 10 January. Compression better than before! Cylinder 1: 130 psi; Cyl 2: 140; Cyl 3: 140; Cyl 4: 140.

Plug 3 ceramic casing cracked 11 January; changed for new; no difference.

Still waiting on taking it to a mechanic...nothing gets done when I'm not there to do it.

Fin

"Running very rough, such that engine is shaking hard against its mounts. Revs will not rise above 1700 and usually not above 500 without lots of persuasion."

Check and double check the firing order for the plugs!

Taupe

Checked, double-checked, triple-checked, quadruple-checked, and quintuple-checked (and more), Taupe -- it's absolutely certainly correct. Thanks though! (Something I overlooked in the list. There will be more such things...but I hope that doesn't stop suggestions).

I'll check once more, though, when I return home in a week.

Hi Fin,

Have you checked the vachum advance mechanism? you did say the distributer had not been removed for a while, but you did point out it was running well in December it could be stuck?

Fin, you may want to check the exhaust, to make sure that it's not plugged.
There was another thread on here recently, where that was the problem.
http://www.mmoc.org.uk/viewtopic.php?f=4&t=48613

Never heard what caused the blockage, mice nest perhaps?

HTH, Ken

Very intriguing! Looking at your list it looks like there's not much left to try!

Other than the other useful suggestions, Could it be that something has contaminated the fuel supply: diesel, water, angry neighbour? It reminds me of a new motorbike I had once that had a faulty seal on the fuel filler and rain water used to get in to the tank. Ran like a pig, wouldn't rev and lost power and eventually died! If you haven't already, try a fresh fuel supply (bypassing the tank and fuel lines to test it). Any smoke coming out the exhaust?

Does your coil get very hot?

Not having got this far on my traveller I can't offer specific advice, but my other project car has a 'bench set up' in the manual for rebuliding the carbs. You mentioned previously it could be partly a flooding problem.

Also, can you get your hands on another distributor, (from your other car perhaps, or a loan) just to rule out wear? Shame to change it if its not needed, but worth ruling out?

Perhaps we should run a forum sweepstake on the outcome. My quid is on the distributor..

Katy, that's a good idea. I'll check that as soon as I go home again (a week from Thursday). I guess I just try and blow through the pipe at the manifold end?

Romek, those are some excellent suggestions.
As to the fuel problem, we hadn't had precipitation for a week before it developed the problem (I checked in the weather records), so I doubt it's water getting in; but draining the fuel, flushing the tank, and putting new in is a GREAT idea. I'll do that straightaway as soon as I get home. No undue smoke from the exhaust (one expects a little vapor in cold weather).
As to the coil, I haven't felt it while it's running, but that's something I'll check. I did try and test the resistance in the ohm, and my multimeter gave strange readings -- high resistance, rather than no resistance as one would expect with a failed coil. I haven't tried a spare coil.
I did rebuild the carburetor, and put new jet and needle in it, but with the engine running so bad I'm unsure how to "tune" it accurately.

As to the distributor...well...that seems likely to me too. I have spare dizzies, but I don't know if any of them are good; Stiltzkin doesn't even have an engine, much less a dizzy. Certainly it's worth ruling it out. The dizzy is the DM2 model, by the bye.

Here's a possibility: the low-tension lead is badly frayed at the connector end. I've ordered a new one and I'll see if that makes any difference.

Hi Fing sorry to hear of your problems, you mention you rebuilt the carb well my money is there. Take it apart again fit the old needle and reasemble as per instructions from SU. Good luck.

You know these symptoms are the same as STALE unleaded petrol. Unlike the good old leaded petrol UNleaded goes off in about 3 months. It give the symptoms you have. When unleaded goes off it smells slightly fishy. Just adding fresh petrol livens it up, no need to throw old stuff away

Can always save it to clean parts aswell.

Thanks for playing, SUE, but it can't be the carburetor -- the engine began its horrid running with the old needle and jet. I only replaced them after removing the engine again, and it made no difference.

I suppose we'll put the gasoline and the dizzy at the top of the leader-board, but since it's easier, I'll try the fuel first! Haven't smelled anything fishy (except the old oil from the dampers!), but it's worth a shot, of course.

It was at least partially the fuel. I bought some proprietary "gas refresher" (Sea Foam brand), and put half the bottle in the fuel tank, then ran the engine briefly.

Results: the running smoothed out A LOT, and the engine now responds pretty affirmatively to the accelerator pedal. I managed to get it to 3000 rpm without any trouble. Varying the timing also seems to make a difference, though smaller than I would expect. However, it's still not running very happily, and it now is having a tendency to backfire through the carburetor. That indicates either a stuck-open inlet valve, or timing FAR out.

More work to come...

It turned out that the remainder of the problem (well, mostly) was down to a soaked spark plug. Once I dried it, the engine fired up and ran beautifully (relative to how it had been!), but it still needed the timing and mixture reset.

I've tried to get those right, and I think the mixture and idle are around the mark; the idle is about 1000 rpm, which is a bit fast but the engine sounds happiest there, and the backfiring (which had transferred from the carb to the exhaust) has ceased. But I feel wholly lost in setting timing. I'm supposed to be listening for something nice, "just before pinking" whatever pinking is, but WHAT am I listening for?

Test-movement in an hour or two, I hope, and a proper test-drive out on the road tomorrow.

The car can move under its own power again. Very pleased about that. It drove pretty well, though I'm rusty on my Minor motoring skills.

I've done other things too!
The spare tire is now mounted on its rim:[frame][/frame]
And the spare is securely at home in its bay:[frame][/frame]
The junction box (because I have an alternator now!) is firmly mounted on the firewall:[frame][/frame]
And the door pulls are mounted once again:[frame][/frame][frame][/frame]