Leaky valve cover gasket?
- Thread starter taylort232
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I just did my 94's head cover gasket and it turned out it was leaking from pretty much everywhere. The head cover gasket was shrunken and brittle, the spark plug tube gaskets were all leaking and rock-hard, and the half moon FIPG was failing. The materials just aged out.
It was hard to pin down because it was lots of smaller leaks, not one big obvious leak, and much of it was under the plastic trim pieces. The oil was coming up the tubes and running down the channel to the back of the engine, blowing around making a mess as it went.
Pop those trim pieces and you may see an obvious source.
It was hard to pin down because it was lots of smaller leaks, not one big obvious leak, and much of it was under the plastic trim pieces. The oil was coming up the tubes and running down the channel to the back of the engine, blowing around making a mess as it went.
Pop those trim pieces and you may see an obvious source.
- Thread starter
- #3
How big of a job is it? I’ve had some oil loss (that I thought was the rear main until I saw how wet this area is), so I feel like I need to do all of these seals also. But the wife is getting tired of all day cruiser maintenance jobs!
Remove and check the breather hose for cracks, if damaged or the rubber is brittle/hard replace with a new hose, then clean off that area
and watch closely to see if/where it reappears.
If the valve cover gasket is the original it's way past time to replace it along with the spark plug tube seals.
and watch closely to see if/where it reappears.
If the valve cover gasket is the original it's way past time to replace it along with the spark plug tube seals.
There is nothing particularly challenging about the VCG, it replaced mine because the tube seals had not been done previously and it made replacing the lower PHH pipe bolt possible. I think @Kernal's comment above is worth considering, the stuff I see leas me towards the breather hose.
The only other point on the VCG is the torque on the bolts is petty low and really not more that seating the letting "legs" on the cast cover to the surface of the head.
The only other point on the VCG is the torque on the bolts is petty low and really not more that seating the letting "legs" on the cast cover to the surface of the head.
I had to do my head cover gasket because the leak got bad. To take off the head cover you have to remove the throttle body and I think the EGR. That gives good access to a lot of old stuff that may never have been replaced.
I went this route, and it may work for another DIY mechanic with aging original parts.
1) Remove throttle body, EGR, and head cover - This is the minimum for servicing the head cover gaskets.
2) Remove the upper manifold and then the master cylinder and booster. My booster was all but dead and needed service anyway.
3) You now have "easy" access and can R&R all the heater and bypass hoses, vacuum lines, vacuum switching, the fuel filter and soft fuel lines, the TVV, etc.
4) If you're ever going to fire your parts cannon, do it now.
5) Service or replace the assemblies you removed. I replaced my failed booster and my very old MC, my ready-to crack air cleaner hose, the EGR, etc.
For small to medium parts I replaced almost everything I touched, and most of it wasn't that expensive. The brake booster was a lot, the MC wasn't cheap, and the EGR wasn't cheap, but most of the other valves, sensors, switches, filters, etc, were a lot less than I'd expect.
There are good youtube videos for all the major steps, and a few specific tools required for some of the tight spots.
I turned it into a bigger job than it needed to be, but I didn't want to miss the opportunity. If you need to minimize, just do steps 1 and 5. Plan on replacing your HCG, tube gaskets, TB gasket, PCV valve and grommet, plus the two vent hoses that will probably crack.
T
I went this route, and it may work for another DIY mechanic with aging original parts.
1) Remove throttle body, EGR, and head cover - This is the minimum for servicing the head cover gaskets.
2) Remove the upper manifold and then the master cylinder and booster. My booster was all but dead and needed service anyway.
3) You now have "easy" access and can R&R all the heater and bypass hoses, vacuum lines, vacuum switching, the fuel filter and soft fuel lines, the TVV, etc.
4) If you're ever going to fire your parts cannon, do it now.
5) Service or replace the assemblies you removed. I replaced my failed booster and my very old MC, my ready-to crack air cleaner hose, the EGR, etc.
For small to medium parts I replaced almost everything I touched, and most of it wasn't that expensive. The brake booster was a lot, the MC wasn't cheap, and the EGR wasn't cheap, but most of the other valves, sensors, switches, filters, etc, were a lot less than I'd expect.
There are good youtube videos for all the major steps, and a few specific tools required for some of the tight spots.
I turned it into a bigger job than it needed to be, but I didn't want to miss the opportunity. If you need to minimize, just do steps 1 and 5. Plan on replacing your HCG, tube gaskets, TB gasket, PCV valve and grommet, plus the two vent hoses that will probably crack.
T
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It's actually not that hard to do. The hardest part for me was the spark plug seals, they had perished & broke up when removing them, but the steel part of them was wedged in tight. Got them out eventually with a chisel & a lot of swearing. Only a couple of scratches on the cover. All good now though.
Timmy The Toolman has a great video of the job here. > FZJ80 Valve Cover Gasket Job - https://forum.ih8mud.com/threads/fzj80-valve-cover-gasket-job.1218341/
Don't forget to order new throttle body gasket & replacement PCV valve, grommet & hoses. They will most likely need replacing too. See the video.
Timmy The Toolman has a great video of the job here. > FZJ80 Valve Cover Gasket Job - https://forum.ih8mud.com/threads/fzj80-valve-cover-gasket-job.1218341/
Don't forget to order new throttle body gasket & replacement PCV valve, grommet & hoses. They will most likely need replacing too. See the video.
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Easy enough job. You can see some pics and stuff in my injector replacement writeup.
cheers,
george.
cheers,
george.
That happened in every video I watched, and it happened to me. I had decent luck starting them by prying with a seal puller, a screwdriver, and then getting a metal trim removal tool under the lip and prying them out.
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all i see in the picture is a tiny bit coming from that breather hose, i would just start with that first.
- Thread starter
- #11
Thanks for the advice fellas. I will start with the breather hose.
