Worn/cracked valve guide seals

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texasmike

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I'm finally getting to the end of a 2-1/2 year and very expensive restoration of a company truck. It had 52,800 miles and was parked outside on the dirt in our yard in 2005. The owner gave it to me in 2018 when I retired and decided it would be nice to have a truck around the house.

All cylinders tested with good compression and the engine runs well but the smoke on startup is starting to get a little worse. I wish I would have taken care of this before all the body and paint work was completed but it wasn't smoking that much when we got the truck running. It's only been driven about 400 miles since I started this project but the truck looks too good to have this issue.

How big a job would it be to attempt this on my own? I was a teenager in the early 60's and loved working on cars but I would be considered a shade tree mechanic at best. I have rebuilt engines in the far past and done valve jobs but with the heads off. I have tools and an air compressor but I have never attempted anything like this. I have a fear of dropping a valve into the cylinder and then having to remove the head. I am starting to lose trust and confidence in outside repair shops and will someday write about some of the bad experiences I have had.

Thanks in advance for the advice.
 

Dutch Rutter

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I've never had to do it myself but if I do. I figured on packing the cylinder with a soft rope through the spark plug hole. That just seems like there is less room for error. And your not pumping compressed air into your cylinder walls.
 

texasmike

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Good idea, what device/tool do they make to remove the valve spring?
 

Bennyt

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Haven't done it in many years but I think the last time I started after work and finished in time to go out with friends so 2-3 hours.

Pull plugs,
Lots of rags on oil drain back holes so you don't lose a valve keeper. They like to stick and fall off at the worst time.


Follow firing order and each cylinder at TDC just in case the valve does fall, it can only go a little bit.
I've used rope once but every other time I used compressed air. If you go slow or taking multiple days, use rope.

There are two different tools available, one I believe you can rent for free at the local chain store is small spring compressor that clamps onto the spring. Its cumbersome and slow but works and cheap to buy.

I used to borrow a tool from my friend that hooked under the rocker arm nut and you pressed down on the spring retainer. Get that one if you can as it is easy to do one handed and leaves space to work.
 

texasmike

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If the piston is at TDC just before ignition, both valves should be closed. Is the compressed air needed only to keep the valves closed (up) when the springs and keepers are reinstalled?
 

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If the piston is at TDC just before ignition, both valves should be closed. Is the compressed air needed only to keep the valves closed (up) when the springs and keepers are reinstalled?

You have to have the rockers off anyways to get to the valves, so they will all be closed no matter what. I did this when I had a broken valve spring. I replaced all of the springs and valve seals at the same time. I bought a simple lever style spring compressor that worked "just ok". I would highly recommend getting one of the slightly more expensive ones that clamp to the rocker stud and will go over center to hold the spring compressed. It makes it way easier to get the retainers on during re-installation. I used a compression checker hose with the valve removed connected to my shop air. It worked great. I basically removed all rocker arms and spark plugs. Then started at #1 and hooked up the shop air. Be careful before you do this as it WILL spin the engine over if the piston isn't exactly TDC. once shop air was holding the valves closed, compress the spring and use a magnet to grab the retainers when they pop loose. Then replace the seal and reinstall everything before moving on to the next one. When you get done changing all of them, turn the motor back to #1 TDC(make sure the distributor rotor is also pointing at #1 so you know you aren't 180 degrees out) and set the initial valve lash on the #1 rockers. Then rotate the crank 90 degrees between setting the initial lash on each cylinder in order of the firing order.

Be careful if your valves aren't seated well due to being worn. Shop air won't want to hold the valves closed well if there is a lot of leakage past the valve.
 

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And put the parts on cart next to the truck, not on a tray on the engine. Everyone knows if you place a tray on the engine, Murphy will show up and turn your simple valve seal job into a head gasket replacement.
 

Ricko1966

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I have every valve spring compressor know to man, okay maybe a few short off that, but for what you are doing I would use the simple lever type.I"'ll try to find one I can link to here. BRB.

https://www.jegs.com/i/JEGS/555/805...MIxurhxZbA7QIV8eHACh2cRAOXEAQYByABEgLrFfD_BwE

https://www.mechanicstoolsandbits.com/gearwrench-383d-valve-spring-compressor.html

As others have mentioned, do cylinders at TDC. use rope or air to hold the valves, I've always used air. I'll make you a cheat list as to which cylinders to do when, you can do multiple cylinders in 1 position then rotate and do the others. Edit. I just read BExtremes method his way would be less confusing for a novice. And if you have a problem with the crank trying to turn. NBD tough to explain but open a pipe wrench up enough to slip top jaw inside the pulley area of the balancer bottom jaw on the pulley surface wedge something against the side of the handle.
 
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Bextreme04

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I have every valve spring compressor know to man, okay maybe a few short off that, but for what you are doing I would use the simple lever type.I"'ll try to find one I can link to here. BRB.

https://www.jegs.com/i/JEGS/555/805...MIxurhxZbA7QIV8eHACh2cRAOXEAQYByABEgLrFfD_BwE

https://www.mechanicstoolsandbits.com/gearwrench-383d-valve-spring-compressor.html

As others have mentioned, do cylinders at TDC. use rope or air to hold the valves, I've always used air. I'll make you a cheat list as to which cylinders to do when, you can do multiple cylinders in 1 position then rotate and do the others. Edit. I just read BExtremes method his way would be less confusing for a novice. And if you have a problem with the crank trying to turn. NBD tough to explain but open a pipe wrench up enough to slip top jaw inside the pulley area of the balancer bottom jaw on the pulley surface wedge something against the side of the handle.

that’s the compressor I used. It was what was available at the local parts store. It worked, but I found it wanted to pitch to the side and made it hard to get the keepers in place. It was also tough to hold the spring compressed, keep the valve held up, and get the keepers installed. It was cheap and available now, which is why I used it, but I read a few reviews that talked about a different style that went over center so you didn’t have to hold it, and I feel that would have been much easier, even though I don’t have any personal experience with that style.
 

Ricko1966

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You know I've been doing this over 40 years.IDK if we bought different brands I don't even know which brands I have even.But could be they aren't as well made anymore, or I'm just so used to it that its comfortable, I've noticed that, things that seem hard to others seem easy to me just cause I've done it so much. That's why I put in That last post your methods on this would probably be better than mine for a novice.
 

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Lisle 16750 looks like it would work pretty well.

The tool I used to use was a lever similar to what others have shown but had a swinging attachment with a "cup" that hung down and provided direct pressure down onto the spring as opposed to pushing off to the side.
 

Backfoot100

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Lisle 16750 looks like it would work pretty well.

I just did this procedure a month ago. That’s the same tool I have. It’s works perfectly fine but do yourself a favor and go to Lowes and pick up a bolt and washers that’s the same size as the bolt on the tool with the lever attached. You can unscrew the lever when you get to tight places like cylinder 7 by the brake master cylinder. Screw in the bolt and just compress the valve spring with a wrench instead of the lever. You may have to play around with the number of washers to put on it for proper compression of the valve spring. Ask me how I know this. That’s why I have a bolt and washers taped to my tool in the pic.

Anyway, I’ve used compressed air for this procedure several times. You don’t have to worry about having the pistons at TDC. Removing all the rockers beforehand will give you more room to work and by doing that the valves are closed anyway so they don’t care where the piston is at that point. The piston will push down to BDC when first putting air in the cylinder so be careful of the spinning fan blade. Make sure you have a good magnetic pick up tool to grab each valve keeper when you remove and replace them.

You just have to make sure the piston for each cylinder is at TDC on the compression stroke before adjusting the valve lash when putting it all back together. Follow what @Bextreme04 stated in his post is a great guide to follow.

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75gmck25

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When I removed the double springs from my new Blueprint heads I used one of these valve spring compressors. It is very easy to use and it has very positive control of the compression. Pushing the lever down all the way makes it go over center and lock down in place, so you then have both hands free to remove the keepers.https://www.summitracing.com/parts/...YDs4qqLw4wC667ld6x6a4w58RdIfGwGkaApBIEALw_wcB

Bruce
 

RetroC10Sport

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I used a valve spring compressor to do mine without removing the heads. I used a strong rubber band around the jaws to keep them from slipping off and a magnet for the keepers. Took me a weekend but I took my time and did a bank a day. I didn't have any rope so I used CAT5 cable in the cylinder chambers. Truck runs great now and no smoke.
 

texasmike

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Thanks everyone for all of the help and ideas. Auto Zone rents tools for free so when I get ready, I plan to use the one they have. It may take a little longer but it looks safe and easy to use..
 

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