Range EFI 3,9 valve stem seals replace or not ?

My heads are off. I just discovered my rangie has no seal on exhaust valve, and just a flat black rubber disc on intake valve. Question, should I upgrade to neoprene fully enclosed seals on all 16 valve guides ?

Yes

The old rope down the cylinder trick to trap the valves in place when you release the collets but if the heads are on the bench it's definitely a good idea to "belt and braces" the job

As the heads are on the bench do the whole job. Doesn't take long and def worth it.

1. Valve springs off & remove valve. Best to keep them in order.
2. Check for guide wear & side to side movement on valve stems.
3. Clean valve faces & stems. (easiest to do with drill mounted in vice & valve spinning in the drill)
4. Clean head
5. Lap the clean valves into the cleaned head.
6. Re-assemble including new stem seals.

It should run better afterwards.

Mark Piercy said:

The old rope down the cylinder trick to trap the valves in place when you release the collets but if the heads are on the bench it's definitely a good idea to "belt and braces" the job

Click to expand...

Problem is that I need to change guides with the new seals

Why ? Valve seals usually slide over the valve stems & around the top of the guides.