Replacing Valve Springs w/out Removing Heads

Replacing Valve Springs w/out Removing Heads

This is a Mustang I got in the shop for service, regarding a little mishap with conical valve springs. The customer was lucky enough not to have the valve drop into the cylinder or cause any damage to the piston/valve. What follows is a pic of the valve in question.... I installed the tie wrap to make sure the valve wouldn't fall in the cylinder before getting it off the tow truck, and by moving it around the shop.

The typical breather at the oil fill tube "no-no" causing an unmetered air condition.... which will also be corrected.

The Mustang was bought by the current owner, and he doesn't know what camshaft is installed in the engine. Obviously, I will be checking what camshaft is installed by doing a "modified" camshaft degree. Due to the possibility of having either a B-303 or Stg 1 camshaft is in the high 90% probability + the use of the stock E7 heads.....

: .... I told the customer to procure the Trickflow valve springs kit to replace the ones installed, which are Crane's single conical springs. As you can see, it also has 1.72 pedestal rockers.

The procedure shown here, is for the typical shade-tree enthusiast that does not have an air compressor, or what is known as the "rope method" to ensure the valves will not fall in the cylinders. If you have an air compressor, the rope/twine, may be replaced with a supply of compressed air in the cylinder by attaching a hose adapter in the spark plug hole. FYI

....Even though I do have a compressor, for this type of work I prefer the rope method.

Down to the procedure......

Tools Needed:

Aside the typical sockets, wrenches, screwdrivers, etc......

15/16" socket to turn crankshaft.
~4' - 5' of 1/8" - 1/4" Nylon twine/rope.
Portable Valve Spring Compressor
Soft/Brass Hammer
Flexible Magnetic Pickup Tool
Mini Hook/Pick Tool

Procedure:

Remove valve covers and spark plugs.
Remove all pedestal rockers but leave pushrods on the lifters.
ID the cylinder you will start with the replacement of the valve springs.
Using the 15/16" socket and extension, rotate the crankshaft CW while you apply some pressure on the PR's. Following the open/close events, notice when the intake valve (the one that doesn't have the header tube underneath) raises your fingertip and cycles back down..... stop from turning the crankshaft as soon as no movement is noticed after it goes back down.
Start introducing the nylon rope/twine into the cylinder through the spark plug hole as shown below.

Notice on the picture above, cylinder #6, that the valve with the tie-wrap is the exhaust valve (notice header primary tube below it), and the one to the right is the intake valve for cylinder #6.
As soon as enough rope is in the cylinder, rotate the crankshaft CW until it cannot be rotated any more (rope is compressed).
Before installing the portable spring compressor, make sure you tap the valves and the stem with the soft hammer. A socket extension with a socket also helps to "release" the seal between the locks and the retainers.
Install portable spring compressor, making sure the top tabs of the compressor are centralized on the retainer.... .... when you are dealing with conical (smaller retainers) springs.... you need to center them.
Compress springs and either tap on the retainer or use the small pick to release the locks from the retainer.
Remove locks from retainer and remove compressed spring.
If you are replacing valve seals, this is the time to remove the old and install the new ones.....do it. And make sure the new ones are snug on the seal "lip".
Preliminarily install the new retainer and locks, and measure head-to-retainer closed valve installed height. This valve springs kit has a "gauge rod" to make sure height is 1.800". If height is lower, remeasure with kit's provided shims as shown.

Once height has been set with shims (if required)....place new retainer on new valve spring, and compress spring.

Place compressed spring on valve, make sure there's enough space for locks to be installed, and release spring.

Repeat procedure for other cylinder valve. After finished, rotate crankshaft CCW while pulling rope in cylinder until it can be completely removed.
"Step-n-repeat steps above for the next cylinder, following the firing order, making sure intake valve is closed before inserting valves holding rope.

Here are some pics during the procedure......

Update:

After installation of all the valve springs, I performed a short version of a cam degree to find out the intake open and exhaust close @.050" values in an attempt to ID what cam is installed. Used piston stop, ID'ed true TDC mark on the damper and checked IO and EC events + maximum tappet lift.
IO: 0° TDC
EC: 1° ATDC
Maximum tappet lift for the intake was .309" and .307" for the exhaust.
The results above point at a E-303 as the camshaft installed.

And here are pics of the culprit conical valve spring.