So my dad and I were cleaning the XR2's tappets out since they were so full of gunk they had gone solid. No play in them whatsoever. We've put them back in and torqued up the rocker arms, and when I fired the car back up it sounded really rough. My dad pulled out one of the spark plug leads and it didn't make any difference. One of the cylinders isn't firing at all. Anybody have any ideas as to what could be stopping the cylinder from firing?
Thanks.

 

Dodgy lead, dodgy cap, dodgy plug, dodgy lifters, dodgy valves.....dodgy anything really.

Do a compression test.

 

Did you prime up the hydrolic lifters?

Valves not seating?

^^^^as said do a comp test

Plug? Lead? Valve stuck open?

 

Which cylinder is misfiring. Swap a lead over on that cylinder so you know its not the lead. Sounds to me like its something to do with the hydraulic tappets.

 

Check the lifter/rocker studs to make sure you haven't pulled one out of the head when tightening one.

(Once of course you've decided which cylinder it's missing on.)

 

We've done a compression test and its down on all 4 cylinders. The car was taken out today and given a drive 'round at 60-70mph for about 15-20 minutes. The misfire is still there, and it's the third cylinder (third from the left from driver view perspective.)
We've tried the spark plugs, HT leads, distributor cap etc... Its not any of them.
Anybody have any other ideas.

Thanks.

 

Yes, clearly it's to do with what you have done to the tappets, most likely they are knackered, thus you have bad clearances!

Also the CVH is famed for chocolate cam shafts, so you should put the tappets back in the same order.

As said, it's worth verifying the rocker is ok.

Martin

 

Have you done this?