Anonymous
Unregistered
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I have a 1983 Toyota pickup with 22R motor with 284,000 miles and no major engine work. Oil consumption became high - about one quart every 500 miles. At first, I thought the oil was leaking from the front crankshaft seal. I replaced the seal, and the leakage stopped, but oil consumption was still high. Then I started noticing a little blue smoke from the tailpipe, and I found the spark plugs fouled with lots of deposits, so I realized the motor was burning oil.
I checked compression and found good pressure and uniformity in all four cylinders. Next, I wanted to try replacing the valve stem oil seals to reduce oil consumption, since valve seals are very inexpensive, but my factory manual only described replacement with the head removed. The rocker assembly can only be removed by removing the head bolts. I searched the internet, but I couldn’t find any way to replace the seals without removing the head - or at least without removing the head bolts. After I thought about it for awhile, I came up with a way to replace the seals - without removing the head bolts - that worked great for me, and I’m posting a description of the method here:
1. Set the emergency brake good and tight.
2. Remove valve cover and spark plugs.
3. Before you proceed further, make sure you have no distractions, clear your mind, and give this your full attention. If you lose your concentration, you may drop a valve down inside the cylinder and then you’ll suffer from much regret (and also humiliation if others are present) because you’ll have to remove the head. Stay focused.
4. Rotate crankshaft by hand with a wrench to top dead center (using timing marks). Find the cylinder that is at the top of the compression stroke (both valves closed with both cam lobes pointing down away from rockers). On that cylinder, carefully mark the position of the slots of the valve adjusters on the rockers with a sharp permanent marker so it will be easier to readjust the valves later.
5. Remove one of the valve adjusters.
6. Put the transmission in a forward gear (I used 3rd). Rotate the crankshaft by hand just past top dead center until it stops turning when the play in the drive train is taken up. Apply air pressure to the cylinder through a fitting on the spark plug hole (I used about 60 psi pressure). Compress one of the valve springs (the one under the rocker with the removed adjuster) with a valve spring compressor tool such as Item #909397 from NorthernTool.com ($12.99 plus shipping) - also found in your local auto parts store. Tap on top of the tool lightly with a hammer to free the spring retainer from the valve keepers, and remove the valve keepers (I used a pencil-sized magnet). Remove the valve spring compressor tool.
7. Release the air pressure on the cylinder. The valve will drop down a little bit until it rests on the top of the piston. Put the transmission in neutral. CAREFULLY and slowly rotate the crankshaft by hand a little farther past top dead center until the valve stem drops down far enough to allow removal of the valve spring from between the head and rocker. BE CAREFUL: If you rotate the crankshaft too far, the valve will fall down inside the cylinder. Slide the rocker over as far as it will go on the rocker shaft, and remove the valve spring retainer and then remove the spring.
8. Remove the old valve seal with a pair of pliers (I found that my exhaust valve seals were crumbling). Lube up the new seal with oil and slide it over the valve stem (the seals I purchased from Advance Auto Parts came with a nice plastic sleeve to use to protect the seal from damage by the valve keeper groove on the valve stem). Tap the seal very lightly around the outer edge (not on the lip) using a small piece of wood as a punch and a hammer until the seal is snugly seated on the valve guide.
9. Reinstall the valve spring and retainer. CAREFULLY rotate the crankshaft back to top dead center to lift up the valve stem. Using a thin piece of wood shim inserted between the coils of the valve spring, lever and lift the valve up until it is fully closed. The new seal will hold the valve in place.
10. Put the transmission in a forward gear. Rotate the crankshaft by hand just past top dead center until it stops turning when the play in the drive train is taken up. Apply air pressure to the cylinder to hold the valve in the closed position. Compress the valve spring with the tool, and install the valve keepers. Remove the valve spring compressor tool. Release the air pressure on the cylinder. Reinstall the valve adjuster and locknut on the rocker and check the clearance.
11. Repeat the process (Steps 5-10) for the other valve on the same cylinder.
12. Rotate the crankshaft 180 degrees (one half turn) so that another cylinder is at top dead center of the compression stroke.
13. Repeat the process (Steps 4-12) until all valve seals are replaced.
14. Reinstall spark plugs and valve cover.
15. Recheck valve clearances with the engine hot, as specified in the manual.
Good luck!
After 500 miles, it looks like my 22R hasn’t used a drop of oil. I think I’m good for at least another 100,000 miles on this engine.
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GeriatricToy
Mudrunner
Reged: 01/29/04
Posts: 426
Loc: Lebanon, Maine
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I really thought some of these engine guys would have chimed in on this one by now with some pluses and minuses to your write-up(which was very good by the way). If this is truely a do-able thing, I wouldn't mind trying it. I didn't have the time to do everything I would have liked to do to my engine when the head was off.  Welcome to the board. It's not always this quiet. 
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2000 Tacoma SR5 - Bone stock 'cept a little bling.
2000 Tacoma SR5 - Bone stock.
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Anonymous
Unregistered
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Actually, it's an old trick old geezers like me have seen before....It's also usually a temp fix cause the stem guides tend to get worn egg-shaped top n bottom and the valve seats are usually close to their end of life cause the valves no longer go straight up n down.
I would def consider doing it if I intended to sell it soon and wanted a non-smoking engine to display.
Years ago, stem seals didn't last long and would crack and fall off. The valves and guides had plenty of life left in them, so lots of folks used that trick..but now a days, by the time they go bad, it's time for a full head/valve job.
He diserves credit for working/thinking his way thru it and sharing with us.
It's guys like him and 4Crawler that make this a great place for info and workarounds...I'm looking forward to more from him!
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Anonymous
Unregistered
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Why is there the need to continually put the tranny in and out of gear?
It seems like to me that this whole procedure could be done with the tranny in nuetral w/ the Ebrake on.
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GeriatricToy
Mudrunner
Reged: 01/29/04
Posts: 426
Loc: Lebanon, Maine
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Quote:
Why is there the need to continually put the tranny in and out of gear?
It seems like to me that this whole procedure could be done with the tranny in nuetral w/ the Ebrake on.
I think it's so the crank will be sure not to move once you have it where you want it. With the tranny in gear, it will be sure not to want to rotate.
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2000 Tacoma SR5 - Bone stock 'cept a little bling.
2000 Tacoma SR5 - Bone stock.
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Anonymous
Unregistered
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Geriatric is right. When the tranny is in gear, in keeps the crankshaft from rotating when air pressure is applied to the cylinder. The piston stays near the top of its stroke, so the valve doesn't fall down inside the cylinder when you release the air pressure to the cylinder.
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Anonymous
Unregistered
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Yep,
He is making sure the piston stays up so the valve doesn't drop into the cylinder.
Not really necessary to have truck in gear, but it is good insurance especially if you are using air pressure thru a sparkplug hole to hold valve seated....the air pressure can force the crank to spin to where the piston goes bottom dead center and then one little bump on the valve will cause it to drop into the cylinder.
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4Crawler
Toyota 4-Wheeling Forum Moderator
Reged: 01/12/00
Posts: 12144
Loc: N. California. USA
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I may give this a shot, I think my seals are dried out (sitting nearly a year w/o running the engine likely cause) and since the head and valves are only about 6 years old, I doubt there is a lot of wear. I burn oil only under high vacuum engine braking, and have had bad valve stem seals in other engines as the cause of that in the past.
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r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
4Crawler OffRoad - 4x4Wire discount code
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Esquire812
Trail Leader
Reged: 04/25/02
Posts: 5688
Loc: Port Orchard, Washington
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Another way to do this is to pull the sparkplugs, bring whatever cylinder you are working on too TDC and then feed a length of rope into the plug hole. Be sure to a tie a fat knot in one end to prevent accidental disappearance to the inner depths. The rope fills the cumbustion chamber and prevent the valve from slipping down the guide..plus its soft and SOLID...aint gonna leak past your rings. When I did it I used a screw top valve spring compressor and a magnet to pull the keepers...rockers were a PIA to get out of the way. After doing 1st cylinder, extract the rope and move onto #4. After #4 cycle the engine and bring #2 and #3 up for their turn. Hemp rope works great btw. No quick job by any means...but a helluvalot quicker than head R&R.
~Darin 
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88' 4x4 *22R-EB Gen II*
87' $Runner *22R-EB Gen I*
85' Sillyca 22R-Esq
"I LIVE IN MY OWN WORLD...THEY KNOW ME WELL THERE"
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Anonymous
Unregistered
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If anyone besides original poster can do it, it's 4Crawler.
He will take pics too, I bet....And offer the whole evolution as a tech article. 
Rog, please take care not to bend a valve when compressing the spring. Place the spring compressor lever carefully(I bet you will make your own)and feel carefully for binding as you compress the springs. Put a dab of grease on your magnet to make certain the stem locks don't get knocked off and fall into never-never land.
Once springs and retainers are out of the way, drop the valve off it's seat and wiggle the stem in the guide...eye-ball/feel the stem-to-guide clearance and decide if she needs a valve job based on her wiggle factor. Valve guides will wear perpendicular to rocker shaft axis, but can't be measured/seen/felt unless valve is off it's seat.
Before you start, eye-ball the intake side and make sure you have clearance to lever the spring compressor downwards. The intake stuff can get in the way....it's on that side I might expect you would fabricate your own spring compressor.
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