I wonder if that can be done without removing the head. The old guide has to be removed. You have to push it down and out the bottom of the head or push it up from the bottom of the head. Maybe there is a tool that would allow you to pull the guide from the top.
The new guide has to be reamed to size. I doubt of you want the material that is removed during the reaming operation to fall into the engine.
If you are trying to reduce the oil going past the valve stems you could try the approach I used. I installed a set of Ford valve umbrella seals on the valve stems. I did it without removing the head. I have a spark plug adapter that allows me to connect an air hose to the head. The air pressure holds the valves up so you can remove the valve spring retainer and keepers. There is a valve spring compressor that hooks onto the rocket shaft so you can push down on the retainer. I used a small magnet tool to grab the keepers.
The car does not leave a cloud of blue smoke when I drive away from a stop.
As I noted in my post you do not need to remove the head to install the stem seals. I will dig around the shop tomorrow and find the part number for the seals I used.
Here are the essential "ingredients" I used to install the umbrella seals. I will not get into the discussion abut whether it is best to use compressed air or the rope method to do the job. Both have advantages and disadvantages. I prefer the air method.
The valve stem seals are for various V8's so you have to buy a pack of 16. I think I bought these at Advance Auto. As expected they did have to order them. You might be able to do the Amazon or Rock Auto thing to get them. I like to support my FLAPS if possible.
Most FLAPS also carry the spark plug adapter. I don't know how long ago I bought that but I remember it was a pack of 2 so it fit both 14 mm and 18 mm spark plug holes. I did not have an extra air coupling with external threads so I had to install the short nipple. That works ok in this situation but the extra length might be a problem for other applications.
The spring compressor is a KD Tool 2400. We bought this one in 1984 when we were racing the Renault Encore in the Renault Cup Series. They sealed the head to the engine between races. So we needed a different way to change valve springs.
As you can see the hooks catch underneath the rocker arm shaft so you can push down on the valve spring retainer. The trick I used on my '37 was to move the rocker arm away so it was not over the valve. I turned the engine so the cylinder I wanted to work on was at TDC and both valves were closed. I loosened the adjusters on the both rocker arms enough so I could slide them on the shaft. Then I connected the air hose to that cylinder. Make sure the transmission is in neutral and keep your hands away from the fan. The air pressure will drive the piston to BDC. I tapped the top of both valves with a hammer to make sure they were seated. I then used the KD tool to push down on the retainer and removed the keepers.
I removed both springs and used a rubber band around the valve stems in case I lost air pressure and the valves wanted to drop. That way I could take my time to clean the springs retainers and keepers before re-installing them.
I put a little bit of oil on the bottom of the seal to make it easier to install and reduce the chance of cutting it on the end of the valve stem. (Remember to remove the rubber band before you install the seal!) Push the seal all the way down to the boss on the head. The first time the engine turns over the seal will move up on the stem to where it needs to be for proper travel.
Reinstall the spring and retainer. Push down on the retainer and install the keepers. Tap the top of the valves to make sure that the keepers are seated. Release the air pressure on the cylinder. Move the rocker arms back into position. You might have to turn the engine over to get that cylinder back to TDC so you can reposition the rocker arms and make an initial adjustment.
I am sure there are others that have lots of tricks and faster/easier methods to do this. I used this approach because I could easily track my progress and knew I would not damage anything.
I use a similar process as Rusty except when I put the piston to TDC put the trans in top gear with emergency brake applied, in most cases it is a less likely for the compressed air to force the piston down (automatic transmission does make that more difficult). Tony
I can understand your approach and definitely see a major advantage to it. If by chance you lose air pressure the valves will only drop down until they hit the top of the piston. If the piston is at BDC there are some situations when the valves could drop completely into the cylinder.
Most of the cars I have done this on were automatics so I just got use to the piston going to BDC when the air pressure was applied. Plus on the ”˜37 I maybe got a little lazy and did not want to mess with putting the car in and out of gear every time I moved to the next cylinder.
Either way I still like using air pressure rather than trying to push a rope through a spark plug hole.
If you regulate the air pressure to 10-15 psi it should not move the piston from TDC but be enough to hold the valve in position unless it leaks badly. If that is the case the head has to come off anyway to fix the valve-seat condition.
