I've got an 87 XF which has a reconditioned motor in it with nearly 100'000 on it. A few months ago it started running really rough mainly when cold and stalling. This later progressed to full time problems idling (almost immediately after an oil change). Problem was at times it would idle smoothly for a little while and then return. Drivability was not an issue. Had me absolutely stuffed so I replaced the carby, Checked all seals, pipes, played with choke, re-tuned it, new leads, new spark plugs, checked for sticky valves, compression tests etc,etc. By pure luck (just as I was about to rip off the head suspecting a burnt exhaust valve) the engine started making tack-tack sounds. Straight away I suspected and found one of the hydraulic lifters was the cause of all my problems. Cost me $2 for a second hand lifter and an hours patience pulling out the old lifter. The old lifter was very worn on the bottom. It was so worn that when sat on a level surface it had a very noticable lean. This lean explains why the car sometimes idled o.k. - as the lifter would rotate in its' bore. The motor now runs fine again.
What I would like to know is - is this a common problem with XF or all 4.1 motors? I've heard that oil galleys on these cars are known for problems. Or, is just a case of the tappet being "lazy" and copping a hammering from the CAM? Could it be the people that reconditioned the motor did a poor job as 100,000 is not that much milage for this sort of problem? Could the CAM be worn? Anyone else had this problem? Any other thoughts.
I have an XE ute which I am having the exact problem with. Idles perfect one day and the next it sounds like it has a burnt out valve. I tracked it down to N*2 cylinder but it has always had a very bad rattly tappet so suspect it would be the lifter failing as well.
Take the rocker cover off an let it idle. You will very quickly see which valve is not being pushed down enough. You may also spot less oil been brought up to the rocker. Despite what the Gregories Manual says you do not need to remove you head to remove a lifter. There's a special tool you can use. If it is a lifter get out as soon as possible. Other wise the bottom of them gets mashed up which makes them hard to get out. Like I said mine took me an hour or so. If they are to mashed you will need to remove the CAM shaft and knock them out.
its very common on those motors, if your lifter is mushroomed on the bottom, then put a new cam in (and full set of new lifters), cos your cam will be worn aswell, it will just root up the new lifter... ive seen cams and lifters only last like 4000km. and make sure you bed the new cam and lifters in properly...
I recently had a bent push rodand i checked the lifters while i was trying to figure out why. The easiest method of removing the lifters is to get a bit of wire about 300mm long, 2-3mm or so dia and flatten one end to approx 1mm. Bend the flat end 5mm in to 90 degrees. Your wire will look like an L. Use the bent end to fit in the groove that runs around inside the body of the lifter - between the ends of the lock ring. I was able to pull the lifer out of its bore and use an extendable magnet to get it out. Hope this helps details are also in the Ford workshop manual.
The valve now seems to move normally compared to the others and the old Tappet was worn by a good 3-4mm. So, if it's running O.K. now how long would you expect the replacement lifter and old CAM to last? I only plan on keeping the car until Mid next year as it's more trouble than its worth. Would it be fair to say whoever reconditioned the motor did a dodgy job and kept the old CAM? Bit strange that it only lasted less than 100,000km (which includes a head gasket 20,000 ago). Also, if the current tappet wears out I was thinking of just wacking in another one, filing down the rocker turret a little and then selling it. Would this work? - very short term of course.
grinding down the rocker posts is an old trick which works quite well. as for how long it will last is anyone's guess. it all depends on how bad the cam is. once the case hardening on the base of the lifter is worn through, it's only a matter of k's before it becomes noisy.
the cam could have been replaced at time of reconditioning, it would be unusual if it wasnt because the cams are common for wearing out. the motor particularly cam and lifters were probably never "bed in" properly at the initial start up.
__________________ TD Cortina ED XR6 Engine, T5, 9inch, Boyd billets, 4 wheel disc etc
AU XR6 - All the usual goodies not worth bragging about
See them both here <=-- Page Updated 15 October 2006
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.