I am a bit worried about number 4 cylinder

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mick64
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I am a bit worried about number 4 cylinder

Post by mick64 »

I need 4 spark plugs ,I am waiting for them to arrive...

But I have two good ones ,I can get the good ones to fire on all cylinders apart from number 4 ,the rear one....

It has bags of compression and the valves open and close and gapped correctly...

Could the carbe be pushing more petrol into number 4 ?

also in the spare parts I recieved with the car there is a brand new metal bar ,its as long as the bumpers, but is a different shape ,also it has some holes in it....Can anyone hazzard a guess what it is?

I can take a picture tomorrow...
PSL184
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Post by PSL184 »

Firing issue is most likely the ign leads or timing. The front and rear bumper bars are different. Can't think of anything else that long off hand but a picture will surely help ;-)
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bmcecosse
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Post by bmcecosse »

Maybe #4 is just 'flooded'. Leave it with the plug out overnight - then try a known good hot plug in there. But more likely - the HT lead to #4 is broken internally - swap it over with one of the other leads and see if the fault travels with the lead - or stays with #4 cylinder. Could also be hopelessly corroded terminal for #4 inside the dizzy cap - have a look - and clean them all up with a little piece of emery board. Maybe the bar is part of a tow bar arrangement ??
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kennatt
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Post by kennatt »

is the bar not just a spare bumper iron,have a look behind the bumpers and see if its the same as the ones already fitted
mick64
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Post by mick64 »

Hi

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I might be a bumper iron..

It might explain why it wont fit on the front of the bumper...

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LouiseM
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Post by LouiseM »

Yes, definately a bumper iron


Eric - 1971 Traveller
PSL184
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Post by PSL184 »

It sure is :-)
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mike.perry
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Post by mike.perry »

A back bumper iron even (no hole for the starting handle)
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mick64
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Post by mick64 »

fitted new plugs and still not firing on number 4..I have a spark but every time I pull the lead the engine sounds the same and the end of the plug is soaked...both valves are opening and closing...

I think a valve is not seating correctly ,bearing in mind it has been stood since 1995...

head off then?
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Post by mike.perry »

Before you take the head off you could remove the rocker shaft (which you would have to do anyway) and lay a straightedge across the tops of the valves. That may show if one is sitting lower than the rest.
bmcecosse
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Post by bmcecosse »

And then you can apply Release Oil (not wd 40) to the valve stem and gently tap the valves up and down with a light hammer to make sure they are closing ok. If really tight - a valve may have bent a push-rod. Have a look inside the rocker cover. Of course a compression check will tell all!
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