1995 Valve stem seals replacement question

Joined
May 19, 2020
Messages
92
Location
Athens GA
I am going to have them replaced come the first of the year and while doing so is there anything else that the mechanic needs to do while in there? Thanks for your help as always.
 
Joined
Aug 8, 2003
Messages
9,081
If they're not pulling the head, then nothing I'd recommend except for a new valve cover gasket and maybe a PCV valve and grommet. Be sure they know to fully loosen the pleated rubber tubes on the intake and treat them like they're made of fragile old rubber. I've seen many mechanics yank on them to remove them and then the engine doesn't run right due to an air leak/crack in the pleats.
 
Joined
Dec 10, 2007
Messages
9,162
The short fuel (vapor) hose on top of the throttle body, if original will likely be hard as a rock which will need to be replaced IME. Have some bulk Toyota 3.5mm vacuum hose on hand to replace vacuum hoses that area. You'll also need a new Throttle Body gasket.

If the heat control valve on the firewall is the original it's past time to replace it
and with the valve cover off there's a bit more room to dig into that.

And while the valve cover is off is a good time to super wash the oil baffle box area as sludge/varnish can build up inside.

Ask the mechanic to reseal the half moons on the front of the head which need to be removed, cleaned, and resealed using the appropriate FIPG.

The intake plenum (inside) can be cleaned up some with the TB off.
There is an EGR gas tunnel that can become clogged with carbon,
a pain in the arse to clean with the plenum still attached, but it can be done.

If time/money is not a concern remove the upper half of the intake plenum
and have it hot tanked using an aluminum safe cleaner.

As mentioned previously, good time to clean the Throttle Body, but not just
the throat and butterfly, there are multiple vacuum ports that can get clogged up along with the IAC valve port. To clean the TB completely it's much easier to remove the cables and clean it on a bench, but then more work to reattach the cables afterwards. Mark the cable nuts with white paint before loosening and/or measure their depth on the threaded section.

And if you want to earn your LC OCD gold star (and watch your mechanics head explode) while the cables are loose is a good time to repair the rubber covering on the cables which by now is likely peeling on at least a couple of the cables. You can use two foot sections of 3M dual wall marine grade adhesive lined flexble 1/2" ID heat shrink tubing which can be slid over the cables then shrunk using a heat gun to cover the exposed cables.

Here's a parts list (use only Toyota parts except maybe for fuel hose or spark plugs):

Valve cover gasket
Spark plug tube seals
PCV valve grommet
Throttle Body (metal) gasket
IAC valve O-ring (if the IAC valve is removed to clean)
PCV hose
Breather hose
Air intake hose
Water bypass hose (formed hose that runs from the TB to the head)
Water hose (straight short hose runs from the TB to a small metal pipe)
Bulk 3.5mm Toyota vacuum hose (three feet minimum)
One foot of bulk fuel hose or cut to fit Toyota fuel hose
Replace all 13 valve cover bolts if old/crusty
Heat control valve with new hose clamps
Six spark plugs (Denso Iridium TT are good for 100,000+ miles)

Also good time to inspect and rewrap the main engine harness which runs close to the EGR pipe. At least wrap with some sort of heat insulation material/sleeve and hang it back up if it's dropped down. Gently ask your mechanic to be gentle when handling the main engine harness as the wires are known to get brittle with heat/age and he/you could end up with shorts afterwards if the harness is treated roughly.

Probably forgot something.
 
Last edited:
Joined
Sep 2, 2010
Messages
943
Location
Kansas City, MO
The short fuel (vapor) hose on top of the throttle body, if original will likely be hard as a rock which will need to be replaced IME. Have some bulk Toyota 3.5mm vacuum hose on hand to replace vacuum hoses that area. You'll also need a new Throttle Body gasket.

If the heat control valve on the firewall is the original it's past time to replace it
and with the valve cover off there's a bit more room to dig into that.

And while the valve cover is off is a good time to super wash the oil baffle box area as sludge/varnish can build up inside.

Ask the mechanic to reseal the half moons on the front of the head which need to be removed, cleaned, and resealed using the appropriate FIPG.

The intake plenum (inside) can be cleaned up some with the TB off.
There is an EGR gas tunnel that can become clogged with carbon,
a pain in the arse to clean with the plenum still attached, but it can be done.

If time/money is not a concern remove the upper half of the intake plenum
and have it hot tanked in an aluminum safe cleaner.

As mentioned previously, good time to clean the Throttle Body, but not just
the throat and butterfly, there are multiple vacuum ports that can get clogged up along with the IAC valve port. To clean the TB completely it's much easier to remove the cables and clean it on a bench, but then more work to reattach the
cables afterwards. Mark the cable nuts with white paint before loosening and/or measure their location.

And if you want to earn your LC OCD gold star (and watch your mechanics head explode) while the cables are loose is a good time to repair the rubber covering on the cables which by now is likely peeling on at least a couple of the cables. You can use two foot sections of 3M dual wall marine grade adhesive lined flexble 1/2" ID heat shrink tubing which can be slid over the cables then shrunk using a heat gun to cover the exposed cables).

Here's a parts list (use only Toyota parts except maybe for fuel hose or spark plugs):

Valve cover gasket
Spark plug tube seals
PCV valve grommet
Throttle Body (metal) gasket
IAC valve O-ring (if the IAC valve is removed to clean)
PCV hose
Breather hose
Air intake hose
Water bypass hose (formed hose that runs from the TB to the head)
Water bypass hose (straight short hose runs from the TB to a small metal pipe)
Bulk 3.5mm Toyota vacuum hose (three feet minimum)
One foot of bulk fuel hose or cut to fit Toyota fuel hose
Replace all 13 valve cover bolts if old/crusty
Heat control valve with new hose clamps
Six spark plugs (Denso Iridium TT are good for 100,000+ miles)

Also good time to inspect and rewrap the main engine harness which runs close to the EGR pipe. At least wrap with some sort of heat insulation material/sleeve and hang it back up if it's dropped down. Gently ask your mechanic to be gentle when handling the main engine harness as the wires are known to get brittle with heat/age and he/you could end up with shorts afterwards if the harness is treated roughly.

Probably forgot something.
I just want to say that it’s posts like this that make this forum so great and the Land Cruiser community so unique and special.

Maybe it’s thanksgiving coming up, maybe it’s the 🍸 , but just wanted to applaud the time that Kernal and dozens of others take to impart their knowledge.
 
Joined
Sep 30, 2014
Messages
634
I know this is a case of “how far do you go”… but I would be asking your mechanic how much extra to pull the head and do the head gasket.

Just, doing the value stem seals on the bench is much much easier than in the car, and the head gasket will fail at some point so if you’re already 80% there may be wise to just change it at the same time. That will also allow the mechanic to easily change the pesky rear heater hose will definitely needs changing.

I know it’s a slippery slope, but would really suck if you end up having to have the head gasket done in a year or two.
 

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