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Old 09-24-2022, 02:48 AM   #21
SBJ
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Honestly, I'd recommend the slower spring compressor tool. It doesn't matter all that much for releasing the valve springs, but going back together it's nice to actually be able to see the keepers go into their slot and confirm they're actually in before going any further. This is just my $0.02 having used both styles. For the magnetic type you're actually supposed to hit it with a hammer to release the valve spring, although pushing on it works too. It's definitely faster taking them apart but it can be a pain to get the keepers to line up when you put it back together. FWIW that tool works wonderfully on engines with bucket-style lifters (like most older Toyotas) where there isn't enough room to use any other style of tool without taking the head off.

If you have an air compressor and a compression test kit you can use it to pump air into the cylinder and keep the valves in place. Rope or string also works.
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Old 09-24-2022, 03:59 AM   #22
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You just helped me visualize things a little bit better with that comparison, although Iím still not 100% sure how that tool can release and install the keepers by hitting it; but I have a decent idea I think. Itís also clear it works/is an option, but I may rent the spring compressor and do one that way too just to compare.

Iím guessing when you smack it with a hammer to remove them, the magnets pull the keepers out of their slots (canít visualize the slotsÖare there slots in the valve stem holding each keeper in?) when the spring goes low enough to release the tension on the keepers, which is why you have to smack it good and hard to get them to come out it seems.

The installation is where Iím still not totally clear in my head (using either method), but I know it will be clear/obvious once I have the spring out and can see whatís going on. The keepers are 2 semi-circles, but can they only go in aligned perfectly; or does it not matter as long as theyíre installed right-side-up? I assume there has to be some sort of slot for them to go in, but not exactly sure how they would ďfall into placeĒ using the installation tool and pressing down. Maybe from the tension of riding back up the valve stem, and not being sucked out by the magnets, pushes and locks them into place. No one really focused on that detail in the videos Iíve seen lol; but if they have to be in the perfect spot lined up before you push down to install them, I can see why some would struggle. I can also think of an easy trick or two that should eliminate that issue, but will have to test it out first lol.

Gonna find out either way though.
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Old 09-24-2022, 04:21 AM   #23
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Quote:
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If you have an air compressor and a compression test kit you can use it to pump air into the cylinder and keep the valves in place. Rope or string also works.
I donít have an air compressor, BUT, if I connected a free compression tester gauge to cylinder #1 and cranked it a bunch to build pressure; wouldnít that accomplish the same thing?

The only small risk is if you have a SLIGHT leak in the valve or past the rings etc., which still allowed you to build good compression of say 150 PSI, but it slowly bleeds out and then the valve drops into the head out of nowhere. Does that sound like a plausible scenario, or if you have good compression, will the cylinder hold that for ~20 minutes while you change the seal?

Just typing that out it sounds risky without an air compressor to always be helping compensate for any loss in pressureÖÖhaha.
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Old 09-24-2022, 04:44 AM   #24
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Pretty sure I’ve got it figured out now, and this post helps explain it. The keepers are smaller than the valve stem diameter, so you’re basically BARELY bending them open around the valve stem when you smack the hammer on the installation tool, and then they collapse and “grab” the valve stem on the way back up (I believe). That’s also why they preach how necessary grease is using this method, or those keepers probably can’t get past the wide section of valve stem at the top.



When you use the spring compressor, you push the “top hat/retainer” and spring down low enough to where the valve stem is skinnier, and you’re able to slide the keepers in place inside that top hat/retainer. As you release pressure on the spring, the top hat (with keepers inside) slowly rises up the valve stem until the keepers grab the wider valve stem and prevent it from rising upwards.

Is that accurate, or do I have anything wrong there? Trying to get it figured out so I can quit researching/thinking about it until I have the parts and am about to do it haha.
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Old Yesterday, 11:10 PM   #25
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Originally Posted by USCGamecocks20 View Post
I don’t have an air compressor, BUT, if I connected a free compression tester gauge to cylinder #1 and cranked it a bunch to build pressure; wouldn’t that accomplish the same thing?

The only small risk is if you have a SLIGHT leak in the valve or past the rings etc., which still allowed you to build good compression of say 150 PSI, but it slowly bleeds out and then the valve drops into the head out of nowhere. Does that sound like a plausible scenario, or if you have good compression, will the cylinder hold that for ~20 minutes while you change the seal?

Just typing that out it sounds risky without an air compressor to always be helping compensate for any loss in pressure……haha.
No, once you take the valve cover off, you don't want to crank the engine to build pressure, again.

NO AIR COMPRESSOR??? You really need to invest in a good compressor. It's needed if you're doing any maint. How do you keep your tires up to pressure? Seriously, think about your budget on this. You NEED!
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What he is saying is the aerodynamics of a D21 is a brick in the wind.
Probably at least as bad as a Jeep so worse than a cow.

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Old Yesterday, 11:40 PM   #26
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I’ve decided I’m too scared to risk the compressor method anyway, even though the odds are 1/100,000, if the compressor goes out or it’s electric and you lose power or something, the valve stem would fall into the head; and it’s far above my comfort level to have to pull the head and get it out (although I know I’d end up trying it I did). I’d rather spend extra time and eliminate any risk of that at all with the rope method.

I told you though I hadn’t done any kind of work myself before like 6 months ago, and I haven’t had a need for an air compressor haha. I thought I may need one for a leakdown, but was excited to find the compression gauge didn’t need one; and my compression was high as hell (for the engine age) at 175 PSI so I didn’t need one.

I fill up my tires for free at the gas station, and have a slow pump for the cigarette lighter if I get a flat somewhere haha.

Just interested though, why is it a bad idea to build compression with valve cover off? Because it creates a vacuum in there somehow or oil will splash out I assume?
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Old Today, 01:04 AM   #27
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You'll make a mess. I suspect the oil pump turns when you crank the engine.

Still, you need a compressor. There's a Porter Cable pancake compressor, for $50, not far from you on CraigsList. Look for it... you need a compressor.
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Quote:
Originally Posted by Deerhurst
What he is saying is the aerodynamics of a D21 is a brick in the wind.
Probably at least as bad as a Jeep so worse than a cow.
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Old Today, 01:35 AM   #28
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Makes sense, and it does build oil pressure front my knowledge by cranking it.

Sounds like youíre big on air compressors haha. I donít have any tools or anything for one right now, so it would only be for filling my tires or a rare use like changing these valve stem seals; and I still think Iím going to use the rope method because of how pissed Iíd be if I dropped a valve. I like knowing itís impossible for it to fall in with the rope.

Iím sure Iíll end up with an air compressor and an impact gun that attaches to it before too long though. Iíll check out the Craigslist and the brand to see why that one seems worth it.
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Old Today, 02:02 AM   #29
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Also, just to update on the valve stem seal replacement, I think I fully understand how all of the parts involved work now; and Iíve addressed all the questions/concerns I had (I think). Iím pretty sure itís going to be ridiculously easy.

Big thanks to SBJ who helped address the final questions I had, and which confirms that you DO NOT need to remove the cam gear; and rbrown620 who confirmed the exact same info as SBJ.

That alone Iím almost positive prevents the engine from getting out of time, but Iím also only going to be removing ONE rocker arm at a time (although loosening them both fully in sequence per the FSM to avoid warping the head), and then reinstalling bolts to keep the camshaft in place. The rest looks to be a walk in the park, and using the rope method, thereís zero risk of dropping a valve into the head and having to rip the engine apart.
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Old Today, 04:32 AM   #30
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Glad I could help. It won't hurt anything to run the engine with the valve cover off, it'll just make a mess. It's a quick and (literally) dirty way to find noisy valves.

I second getting a compressor and an impact gun. It'll make life so much easier in the long run, and HF has them on sale pretty regularly. Even if not for this job, it's the kind of thing you'll find uses for and wonder how you ever got by without one. Most of my tools are cordless now but every so often I'll come across a stubborn fastener that requires the air gun to knock it loose.
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