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Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 5:27 pm
by TigerWoody
Hello all!
I'm new to this forum and Morris ownership and I need help please from someone with more knowledge that me!!!
I've always driven and worked on old VW's but my wife wanted a Traveller so here we are!!
She's been great so far and we've driven about 850 trouble free miles until today on the way home from collecting our kids from school I received a phonecall from my wife to tell me she's lost all power and she was abandoning our poor Traveller at the bottom of the hill, luckily only just down the road so like the knight in shining armor I am I ran down the hill to rescue them all.
She seems to be only running on two cylinders... (am I right in thinking the firing order is 1432 by the way?), I have the Morris Minor workshop manual(British Leyland) which is great but I can't seem to find out which cylinder's are which so apologies for being so basic but it's the back two(furthest away from the fan).
I've taken the leads off one by one whilst the engine's running and there seems to be a spark to each so I'm assuming that the distributors ok(maybe not open to suggestions!!)... if I take the lead off either of the front plugs the engine dies but if I take them off the rear two nothing happens to effect the running at all indicating to me that the two rear aren't working... I've taken the plugs out and cleaned them but it makes no difference.
Why would two cylinders stop working at the same time?!
Thanks in advance for any help or assistance you may be able to give me!
Kind regards
Chris
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 5:47 pm
by mogbob
Chris
The cylinders are numbered from the front ( radiator end ) 1234.Number the leads in some way, so that you know which is which, when you take them off their respective spark plugs.You can get HT lead markers plastic clips or collars, heat shrink type ones or you could use typists correction fluid/ snopake and brush on a single stripe, 2,3 and 4.
So the problem appears to be with numbers 3 & 4.
If it was running well before, the leads are in the correct order.
What state are the contacts, inside the distributer cap, are they all nice and clean.A clean up with some sandpaper and some Meths on a rag will do.If too far gone... buy a new distributer cap.
How are your HT leads fixed into the cap, push fit or screw ? Check both ends , clean and firmly fixed ?
If you have a multi meter, with the leads detached , check each for continuity / resistance.
The main / king lead to / from the coil will be OK ( as in working the other two leads but clean the connections either end whilst you are in the mood).
If the leads generally are in poor condition buy a new set.
Clean the rotor arm by wiping it against the tyre to get rid of any carbon / dirt.
As to why...old age/ wear and tear/ poor maintainance previous owner / garage/ water ingress/corrision,something dropped on the leads, dislodging the connection....take your pick !
Bob
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 5:51 pm
by mike.perry
Firing order 1342 anti clockwise. If you have 1432 then 3 and 4 would not be firing, check plug leads and caps are all tight whilst you are fitting them in the correct order
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 5:55 pm
by TigerWoody
Thanks for the quick reply and info...
I've just done a compresion test and cylinders 3 and 4 are only 20psi whilst 1 and 2 are 140 and 120 respectively... seems odd to me that two would both loose compression at the same time!?
What do you think could cause this and what options do I have?
Thanks again... much appreciated!
Kind regards
Chris
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 5:58 pm
by mike.perry
Probably the head gasket blown between 3 and 4
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 6:01 pm
by smithskids
I agree with Mike, head gasket sounds like the culprit, its unlikely two valves would stick open at the same time. Good luck.
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 7:37 pm
by TigerWoody
Thanks for that...
I've never worked on a water cooled engine before only ever flat 4 aircooled so never had to deal head gaskets... replacing the gasket... is it as simple(in theory!) as taking off the cylinder head replacing the gasket and bolting it back down?
Thanks again!
All the best
Chris
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 8:12 pm
by bmcecosse
Yes - but let the water out first! It's a 1 hour max job once you know what you are doing. But when the head is off - it would be a good idea to grind in the valves too. What size engine? Assuming 948 or 1098 - buy a 998 Mini head gasket from your local autoparts place.
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 8:32 pm
by moggiethouable
And set the rocker gaps?
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 8:47 pm
by bmcecosse
Why the '?' ??? OF COURSE the gaps need setting if anything is disturbed !
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 8:53 pm
by TigerWoody
Gulp... let the water out first?? do I just drain the water from the radiatior plug(?) then refill after... stupid question I'm sure but aircooled mentality I'm afraid... sorry!
Engine is a 1098(where's the engine number by the way?!) why a 998 Mini head gasket and I was going to call Bull Motif tomorrow or can my local car spares(autoparts) supply as you suggest?
What is the gap for the rockers?
Thanks.
C.
Re: Help... two cylinders not firing?!
Posted: Mon Nov 19, 2012 9:15 pm
by bmcecosse
Don't touch the rad tap - it may shear off. Pull the hose off the water pump. Yes -Mini 998 gasket locally will be cheaper and off the shelf! Valve gaps -12 thou inlets and 15 thou exhausts. When you fit the head back on - torque it to 40 ft lbf and roughly set the gaps. Don't forget to fill water + antifreeze!. Then run the engine through a short heat cycle - then (when it has cooled - but not necessarily cold) retighten to 44 ft lbf, and set the gaps accurately.
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 6:03 am
by TigerWoody
bmcecosse wrote:Don't touch the rad tap - it may shear off. Pull the hose off the water pump. Yes -Mini 998 gasket locally will be cheaper and off the shelf! Valve gaps -12 thou inlets and 15 thou exhausts. When you fit the head back on - torque it to 40 ft lbf and roughly set the gaps. Don't forget to fill water + antifreeze!. Then run the engine through a short heat cycle - then (when it has cooled - but not necessarily cold) retighten to 44 ft lbf, and set the gaps accurately.
Morning
Thanks very much, excellent... all the information I need!!
All make sense, I'll let you all know how it goes!!
Thanks again
All the best
Chris
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 7:35 am
by kennatt
also check he head carefully for burn marks across the two pots,allthough ,since its just happened very unlikely,if there is, may need cleaning up or skimming if deeply scored.
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 7:55 am
by TigerWoody
... just a few more things!!
how do I get each valve in the right position to set?
Are there marks on the pully or do I need to get the piston to the top of it's stroke and do I turn engine 180 anti clockwise from starting point and set 1234.
Also... which are exhaust and which are inlet(sorry!!)?
Thanks again!
All the best
Chris
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 8:22 am
by chesney
Use rule of 9. With starting handle, turn engine until #1 is all the way down, and adjust #8 (1 + 8 = 9) Google if not sure, or get 'AA book of the car' covers everything

.
Order E I I E E I I E, if you get stuck look at the manifold for reference.
Good luck

Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 8:30 am
by TigerWoody
kennatt wrote:also check he head carefully for burn marks across the two pots,allthough ,since its just happened very unlikely,if there is, may need cleaning up or skimming if deeply scored.
Will do... thanks!
C.
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 4:55 pm
by gtt1951
Chris,
I've just had to change the head gasket etc., on my Traveller engine.
In the top-view picture, below[frame]

[/frame]
The font of the engine is to the right (thermostat housing end) and then the valves, going right to left are
Exhaust, Inlet, Inlet, Exhaust, Exhaust, Inlet, Inlet, Exhaust - 4pairs altogether.
If you look underneath, you will see that the Inlet valves are wider than the exhaust ones (grinding in pic below)[frame]

[/frame]
If you don't have a workshop manual, you will need to know in which order to slacken the head-bolts off - and then
to tighten them afterwards - I'll post up a drawing in a moment.
To adjust the rockers - with No.8 valve fully open (down), adjust No. 1 (No. 1 being the one nearest the thermostat housing.
With #7 fully open, adjust #2, with #6 fully open, adjust #3 - see the pattern, the pairs you use all add up to 9.
Use the handcrank to turn the engine (leave the spark plugs out during this process - as it is easier to turn the engine).
[Looks like someone beat me to some of the answer, whilst I was typing this up]
George.
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 4:59 pm
by taupe
dont forget antifreeze when you refill!!!!
Re: Help... two cylinders not firing?!
Posted: Tue Nov 20, 2012 5:26 pm
by gtt1951
I've been looking through the manuals I have and the BMC Morris Minor, Issue 2, service manual actually
has the undoing/tightening order, quite different from the likes of Haynes and Autopress (which now don't look
all that logical). Issue 3 of the (now) Leyland Manual has a drawing instead of a photograph.
Historical photo of page AA.8 follows.[frame]

[/frame]
Regards, George.