Morris Minor Owners Club

Hi,
I´ve got a problem with my Traveller (1098er). After changing the cylinder-head it will not run properly and seems to be some kind of powerless. Idling is ok but its practically not driveable without revving really hard. I changed the ht leads, the condenser and the points. distributor cap is ok, timing is set with a strobo.
It sounds and feels like I have the choke permanently on.
Once again, idling is good, just accelerating is not possible. Maybe some of you have an idea. thank you very much.

First thing I would check is the points gap- either too close (virtually no gap) or too big, and the car will behave like you described. Its happened to me, I got away many times setting the gap "by eye" but last few times I used the feeler guage.

another thing to check is the valve (tappet) clearances- these will need re-setting after changing the head.

check that the choke (at carb end) is not stiuck open too.

Thanks for the reply. Points-Gap has been checked with feeler gauge. Valve-clearance has been adjusted as well after head replacement. I suggest some carb problem and will check choke-cable today.

Is the carb dashpot still full of oil?

Yes, oil is topped up, but its 10W40 Engine oil. maybe this is too thin?? Will check later, if its possible to lift this "piston" in the carb mouth. I should be able to litft it with some resistance and it should come down with a sudden "clonk", right?

Is the mixture very far out? (lift the pin under the carb slightly at idle, revs should very gently raise) What about the rotor arm, is that in good condition?

Is the head gasket sealing properly, any leaks here could cause a loss in power, any water in the oil or oil in the rad?

I'm a novice re: Travellers etc...however, when mine had a similar problem (at different times) it was diagnosed as being because of:
1. The leads being old and useless leading from the spark plugs to the points bit.
2. Head gaskett going / gone.
3. The air filter being clogged beyond belief (removing it gave instant results)

Hope this is helpful
Fab

Are the manifolds tightened up to the head properly?

It's easy to not nip up the middle nuts (the hard to get at ones) compared to the outers which cuases a small leak on the inlets.

look at the things you took off to change the head. usually something simple - are the ht leads in the right order. 1342 going anti clock wise no 1 is at about 2 oclock on the dizzy

RogerRust wrote:are the ht leads in the right order. 1342 going clock wise no 1 is at about 2 oclock on the dizzy

The distributor goes anti-clockwise, doesn't it?

You say you have 'changed' the head. Is the replacement definitely a 1098, if its a 948 head you will have about a 6:1 compression ratio without skimming.
Just a thought!
Nigel

I had a problem after changing the cylinder head once which meant it wouldn't idle but was OK at revs. It turned out to be the casting of the new head was stopping the inlet manifold seating flat on the side of the head so there was a big air leak. I guess that if I'd set the carb really rich then it might have given the same symptoms Bengt describes.

whoops its anticlockwise

Will check later, if its possible to lift this "piston" in the carb mouth. I should be able to litft it with some resistance and it should come down with a sudden "clonk", right?

Good place to start to make sure the piston moves up and down freely just in case you have got a bit of dirt in there.

Hi there,
thank you all for your suggestions.
I´ve now replaced the following: Dizzy Cap, points, condenser, rotor arm, leads. Furthermore cleaned the carb from the inside, checked the manifold for leaks, set the ignition timing, filled up the dashpot and set the poits gap. Now the engine is running fine, idling good, revving instantly from low down. Everything seems to be perfect - as long as i´m not trying to drive the car. When I shifting in first gear and trying to drive away, I can barely keep the engine running. Just seems to have not enough power to drive the car.
I´ve checked the compression with Gunson´s gauge - 8 bar on all four cylinders. Is that too low? When I reassembled the cylinder head I cleaned all the valves and seats. Is it possible that, without all the debris at the valves, they are not closing properly now???

are your brakes binding? No oil in the gearbox? or no oil in the diff? Perhaps the clutch is slipping, thus no power getting to the wheels.

8 bar, what is that in PSI?

For the english folks (or the oldies) 8 bar is about 115psi, which sounds low.
10 to 11 bar is ideal, 150-160psi, as I recall.

I think 8 bar is 116PSI.

1 Bar = 1 atmosphere = 14.7 psi. call it 15 x 8 = 120 psi, which is desperately low. Are you checking it correctly - all the plugs out, engine hot, battery fully charged (and in good condition) and of course starter motor in good working order. Throttle needs to be held open to allow air in. Put the gauge in one of the plug holes and crank the engine on the starter for about 6 seconds - note the reading. Reset the gauge, and repeat on the other 3 cylinders. Now - squirt some oil engine oil into each bore - enough to flood across each piston and run down to the rings - then do the test all over again. Compare readings - if it has risen dramatically then the bores/rings/pistons are badly worn. If not much change - then it could be valves needing re-seated, or just a very low compression engine !! Even so - with 120 psi - it should be able to move the car ok - can you easily push the car by hand ??