Replacing valve seals in a 75 FJ40 (1 Viewer)
- Thread starter Mustard75
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Yep.
Have you done a compression test on this engine? What did you come up with for numbers? Dry?/Wet?
Pull the head and bring it into a machine shop and have it gone through...
This is something that can be done with the head on the engine, and is not that big of a deal...Pull the spark plugs, bring the cylinder to TDC, and feed a nylon rope into the cylinder through the spark plug hole to prevent the valves from dropping...
Good luck!
-Steve
Have you done a compression test on this engine? What did you come up with for numbers? Dry?/Wet?
Pull the head and bring it into a machine shop and have it gone through...
This is something that can be done with the head on the engine, and is not that big of a deal...Pull the spark plugs, bring the cylinder to TDC, and feed a nylon rope into the cylinder through the spark plug hole to prevent the valves from dropping...
Good luck!
-Steve
- Thread starter
- #3
Thanks Steve C. I have been researching how to do this job without messing up. I especially don't want to have to pull the head off. I read something about replacing the valve stem seals with ones that came with the 2Fs in the 1987 FJ60, because it is made with better materials. Anyone know anything about that? Thanks.
The seals for the '87 are a metal/rubber combo that is similar to a oil or grease seal, as it has a small spring on the seal, opposed to the older soft plastic/rubber one piece valve stem seals that were used for years on the earlier engines...which is probably what you will remove..
Good luck!
-Steve
Good luck!
-Steve
I have never tried the rope trick, sounds good. I used an old spark plug, smashed the insulator out, cleaned it up , tried to weld an air hose quick connect and then used that in the same process above with air pressure. I also rigged a bar of Al. as a fulcrum and then used a ball joint tool to force the spring down and then removed the keeper. I think I used the later model seals. I know it sounds funky but definitely worked. However if you don't have good compression, especially wet then you have more problems than your valve seals.
Do a leak down test. The stem seals are just a part of the issue. head removal is no big deal and not expensive. You are right on the different type of seals. All F series seals are the same. Go for 80ish 2F seals which have the spring inside.
- Thread starter
- #7
Just finished doing a compression test. Numbers 1 through 5 came in between 140 and 142. No. 6 came in at 138. This was a dry test and without warming up the engine. If I remember correctly these are ok numbers. I didn't bother doing a wet test. It got dark so I would not have had time anyway. After the compression test, I fired it up. As usual condensation and a little oil came out of the tailpipe. Once it warms up the oil stops coming out, just gray smoke. Am I correct to suspect the valve stem seals are bad, or can it be something else? The smog equipment has been removed from this vehicle. Does that make a HUGE difference? I appreciate any suggestions, advice, etc. Thanks again.
The smog stuff will not have any impact on the level of grey smoke comming out the tail pipe...
I prefer to do compression tests with the engine at operating temp, but to each their own. To not preform a wet test, will not give you anything to base your numbers against, but they really are not that bad...
Change out the valve stem seals.
Good luck!
-Steve
I prefer to do compression tests with the engine at operating temp, but to each their own. To not preform a wet test, will not give you anything to base your numbers against, but they really are not that bad...
Change out the valve stem seals.
Good luck!
-Steve
I used air pressure...the adaptor for spark plug hole is cheap. I also put each cyl. at TDC as a back-up as I pulled the springs. The spring depressor is cheap also, or make one as suggested. The whole job is 1 hr. & maybe 2 beers. Cost--tools & umbrella seals maybe $30 Amazing how well that air press. worked.
Have fun.
Have fun.
- Thread starter
- #10
Thanks for the tips. I might try to do it sometime this month. I've never done this before and just wanted to know if there was something tricky that I should look out for. I asked a mechanic about it yesterday,and he wanted $195 ($65/hr. for 3 hours) to do the job--but I still have to supply the parts. I thought that was a little too much. I guess I am scared of dropping a valve. The engine still runs nice and strong, so I'd rather not have to deal with taking the head off if I drop a valve. I replaced the head gasket on a Honda Civic three years ago, and that was not all that fun.
Do you remove the entire rock rail to do this job with the head still on. I bought a small compressor and the adaptor and the VC is already pulled and ready to go.
I got it.
I'm still wondering if you have to remove the rockers. Can anyone advise?
Yes! So you can remove the two keepers, washer and valve spring to slide on the new seal onto the valve stem. Just remove the whole rocker assembly in one piece. Loosen all of the adjuster nuts first. With the assembly off it's a good time to clean/flush/blow out all the oil passageways in the rocker shaft and the rocker arms.
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Thanks Steamer I will give this a go tonight? Any other advice before I tackle the valve stem seals? I guess it's just a pull and replace type thing.
When I compressed my springs I found the keepers were stuck in the valve stems. Others suggested, before compressing the spring, to give each valve stem a light whack with a brass hammer to shock them loose. What I did, and it worked very well, was to take a 1/4" x 6" brass pipe nipple and cut the threads off each end. Then I slipped the pipe over the valve stem tip and gave it a wack with a hammer.
I had difficulty with the spring compressor I bought for the job and wound up fabbing my own tool which worked a lot better. For me anyway. I threw it together quickly with material on hand. If I were to make another, I'd take a little more time. Here's a "LINK" about it.
I had difficulty with the spring compressor I bought for the job and wound up fabbing my own tool which worked a lot better. For me anyway. I threw it together quickly with material on hand. If I were to make another, I'd take a little more time. Here's a "LINK" about it.
Ok great thanks for the feedback. In this video this guy uses a magnet inside of a spark plug socket to knock his retainers loose. Then he just used zip ties to put the springs back in. Do you think this would work in my scenario?
I really like the socket and magnet trick as well as the zip tie thing. Very clever and simple. I'll have to give that a try next time. However I'm not a fan of stuffing rope into my cylinders. For me, I would stick with the air pressure to hold up the valves.
Good find on that vid.
Good find on that vid.
Bump on this one. If I use the compressor, I know I can find TDC for cylinder 1 (compression stroke). But what about of the other 5 cylinders? Do I need to work about that since I am using the compressed air into the spark plug?
You basically rinse and repeat finding TDC for each cylinder down the line, starting with #1 but that's not a requirement.
