Most engine wear on any engine occurs at startup with that said the R series Toyota engines such as the 18R,20R and 22R all use a timing chain which it's tension is supplied by hydraulically driven timing chain tensioner which has it's oil pressure build up few seconds after the engine has started therefore the timing chain rubs on the driver's side brown colored nylon/plastic timing chain dampener or guide and after so many miles (140-170 000 miles in the city with the average 4 starts per day) the driver's side guide breaks through causing the chain to rub on the timing chain cover for the first few seconds upon startup and when driving in 5th gear and letting off the gas.
Usually by this point the other timing components such as the camshaft sprocket,crankshaft sprocket and chain have their specs out of tolerance and hence must be replaced as well.The tensioner sometimes sticks due to dirt build up and other problems arise as well and must be replaced as well,all of those parts are sold in the aftermarket world as a "timing chain kit" which also include gaskets and a front oil crankshaft seal.Toyota on the other hand for some reason does not sell the parts as a kit but as individual parts which would cost around $400+ and from all of the reading I have done on many Toyota 4-Runner/pickup discussion sites I have come to the conclusion that many experienced off-roaders who cannot afford to buy all of the genuine Toyota timing parts instead buy the chain and tensioner from Toyota and the other parts from aftermarket as a kit but of course don't use the aftermarket chain or tensioner.
The best brand of aftermarket timing chain parts to use on the 20R & 22R series Toyota motors are:
http://www.engnbldr.com/ToyotaHotlicks.htm
http://www.22r.biz/
http://www.rpmrons.com/toyotatiming.html
http://www.toyota-engine-parts.com/
http://www.europeanautomotive.com
and if you choose to buy from Toyota these places have the best prices in the USA & probably the whole world:
http://www.1sttoyotaparts.com/partscat.html (10% shipping)
http://www.toyotadiscountparts.com (free shipping with $100 & up)
http://www.Toyotaparts4U.com
http://www.toyotaofplano.com
Other ways to check timing chain wear are:
http://www.misterfixit.com/chanslop.htm
you can also remove the valve cover and take a flashlight and see if the driver's side timing chain dampener or guide wore through.
You can bend 1 to all 8 valves and have timing cover eaten through if you wait and then coolant and oil mix together to give you butterflies in your stomach.You can do a fluid analysis on your engine oil by going to any Caterpillar and buying a fluid analysis kit for around $15-20 and taking a sample of your old oil.
Finally these sites explain the timing chain replacement well:
http://yotarepair.com/22R timingchain.html
http://www.4crawler.com/4x4/CheapTricks/EngineMods/TimingChain.shtml
http://www.4x4wire.com/toyota/maintenance/timingchain/
1993 Toyota Pickup Service Manual:
http://personal.utulsa.edu/~nathan-buchanan/93fsm/
Any Public Library in your area would have the Factory service manual,Haynes,Chiltons,Mitchells,Clymers,Bentley and Toyota repair books.
There is also free AutoZone service manuals at:
http://www1.autozone.com/servlet/UiBroker?ForwardPage=/az/repair_info/repair_guide/repair_guide.jsp
For scanned pages of factory service manuals for other engines:
http://www.brian894x4.com/Scannedmanual.html
http://home.swiftdsl.com.au/~scorp/surf/1KZ-TE.pdf
http://www.showmesome.info/hilux/info/manuals/1KZ-TE
http://surf.mactherapy.com/1KZ-TE.pdf
http://surf.mactherapy.com/parts/
http://www.spyderchat.com/1zzfe.pdf
http://files.matrixvibe.net/docs/1zzfe.pdf
http://landcruiser.free.fr/mans/
http://surf.mactherapy.com
http://www.turbosupras.com/pages/technical/tsrm.htm
http://www.lieblweb.com/tacoma/Mechanical/96TacomaDiagrams/index.htm
http://perso.wanadoo.fr/adherence.4x4/liens_techniques.htm
http://perso.wanadoo.fr/adherence.4x4/index.htm
http://www.asatraction4x4.cl/html/
http://www.toyotasurf.asn.au/techsite/downloads.htm
http://www.grubinski.com/grubinski/automotive/toyota.manuals/
http://www.carsoft.ru/files/4runner95di.exe
http://www.hotrodder.com/kwkride/tech.html
http://www.autoshop101.com/autoshop15.html
http://www.mtv411.com/sitemap.htm
1993 Toyota Pickup Service Manual:
http://personal.utulsa.edu/~nathan-buchanan/93fsm/
2003 (2001-2004) Toyota Tacoma Factory Service Manual:
http://fsm.afraid.org/
http://www.junglecode.com/toyota/tacoma/2003_fsm/
http://65.200.1.6/FSM/
FSM (factory service manual)can be acquired in several ways:
Toyota Material Distribution Center
750 West Victoria St
Rancho Dominguez/Compton,CA 90220-5538
USA
Ph:1-800-622-2033 (outside CA)(M-F: 7-5 PST)
Ph:1-800-443-7656 (inside CA)
Ph:1-310-818-4630 (in or outside CA)
Speak to Beverly or Deloris
http://techinfo.toyota.com/public/main/mdc.html
http://www.4crawler.com/4x4/FSM.shtml
1)buy a used one off e-bay
2)some Toyota dealerships may give you one or sell it for $10-20 (used) as most Toyota dealerships don't repair many old Toyotas and no longer need the service manual
3)some public libraries sell their old books as they are not in demand any longer
4)some free buy & sell classified papers,websites and bulletin boards may have some used ones for sale
5)some junk yards may have one laying around
6)some Toyota specialty garages may have one laying around and no longer use it as the vehicle may be too old and those mechanics probably have so much experience that they could publish their own factory service manual with corrections and "real world repair tips"
7)if someone has the FSM maybe they could scan all of the pages and post it on a site for all of us to download or view.
Sidney® ™
Repairs tv's,vcr's,home/car audio out of my home
E-mail:sidneybek@yahoo.com
Dartmouth,Nova Scotia
Canada
1985 Toyota 4-Runner,solid front straight axle,factory cruise control,sunroof,22R-E,W56,RN60LV-MSEK,rusted rear step/towing chrome bumper with 244 000 KM
