timing chain & gears

greetings fellow van enthusiast's. new member here embarking on a bhg job. 1986 window van auto. hva eall of the parts off for cleaning, heads in the shop getting surfaced and im looking at the timing chain cover like something is telling me to do tgis now. sound practical at this stage of the game?
my thinking is im at tdc with everything out of the way, why not. im planning on keeping this for awhile. after all, this hg project has been a real task, overflowing with so many tedious details.

whats the word from you owners who have done this add on while doing the bhg job.anything else need doing while im here.

keep the info flowing, its a great resource for a new owner like myself.

thanks - mike

Hi & welcome to TVT! Yes, now is the time. I have done this job a couple times now with aftermarket parts, and both times I've had interference problems (cam gear hits timing case bolts). Unless you are using factory Toyota parts I would recommend carefully checking clearance in this area before final assembly. Here's a post I made after the last time I did the job: http://www.toyotavantech.com/forum/s...2491#post12491. Good luck. Tim

i just now ordered a timing kit (beck arnley) from r auto. thanks for the link, ill keep the site posted on the task when done. hoping for a no issues install, but prepared for whatever.
anything else mechanical at this juncture (a must do too thing) that would be a real roflroflroflroflrofl later on?
one shop suggested that my rings should be replaced as i probably re tempered them. never heard of such a thing. has any one? if so whats the criterion for making the decision to r&r rings? engine has 125k miles.
my 4y head did not pass the water test today. shop said leaking water was seen around the spring of only one valve (underneath it) and it must be cracked there. i'm looking for another head to purchase and shop. is a valve job a must do here. hope to have the bhg job back together soon. any tips on locating one. i understand they are used on toy forklifts. if so what description do i use to search for one? ask for 4y head for f lift? cl reveals nothing. my location is central valley, ca.

thanks for the heads up on the timing chain install with link tim. happy n y to you and yours and especially to anyone out there doing a bhg job. sucky way to end the year. - mike

Yeah, not sure about your rings, nor have I heard the term "tempering" them. Reasons for replacing rings would be bad compression and/or bad oil control. Even with the head off it's still a big job. I've heard of people doing rings with the engine still installed before, but I would never do it that way. New rings need the cylinders roughed up a bit to break in properly. To do this you need to run a hone in them. I would never consider running a hone in an engine with the crank still installed, and the crank cannot be removed without separating the engine from the transmission. Trying to hone cylinders with the crank installed would likely result in nicking/damaging journals not to mention the grit that would likely be introduced and deposited in places you don't want. If I absolutely had to do a ring job with the crank still there I would probably skip the hone part, but the new rings would likely take a very long time to break-in. Best way would be to simply bite the bullet and remove the engine. I happen to be perfoming that job in the thread I linked you to earlier, so if you decide to go that far, start on page 1. If you have no reason to suspect bad or stuck rings, then I would probably chance leaving the old rings in there. Here's a recent discussion we've had regarding piston rings: http://www.toyotavantech.com/forum/s...s-on-87-Van-LE.

Regarding your head, if it's cracked I wouldn't mess it (get another head). If they tell you they can fix it by welding..........run (go find another machinist). You're much better off to go find a good used one to rework or buy a new one. There are new fully assembled Chinese reproduction heads on eBay for a reasonable price. I'm running one right now & I think it's a pretty good value. These can have issues though, and should be carefully inspected before installation. You may also need your machinist to add a hole or two (for your sensors/sending units). I did a detailed inspection and review of one of these heads in my blogs...........Here's a link: http://www.toyotavantech.com/forum/e...Rebuild-part-2. The head is $320 but they're doing free shipping now. Don't forget they'll want your old one or you'll get hit with a hefty core charge (I had to pay $100 to keep my old head). I noticed there's a new head from another seller there now that even comes with a new rocker assembly for less money: http://www.ebay.com/itm/Complete-Cyl...45543f&vxp=mtr. I suspect this one to also be a Chinese reproduction (same thing), but I have no experience with this seller. I would try to avoid the eBay rebuilt heads simply because I know they will often repair cracked heads by welding, and I would be very wary of one of those (sort of a roll of the dice). As a general rule I don't like the big machine shops that do rebuilds because they tend to put out poor quality products. If you're using a local machinist to rebuild a used head, do yourself a favor and find a shop that specializes in racing engines. These guys will likely want a bit more $$$, but will typically do a better job (IMO money well spent). Tim

thanks for the level headed advice, im leaving the rings alone. i want to do as much as is prudent while this motor is stripped down so far, but i like the idea of doing a rebuild when it is not so cold outside as we have been in a freeze since i started this task. high winds all day and holidays dont help the project either. if the hg holds out until summer ends, ill do it all then.
i did not experience too much trouble with the tear down at all. i did not use a manual or look at one until all was removed. took 3 1/2 hours including the infamous hose of death. a huge shop compressor and air tools helped expedite the process alot.i could not remove the plugs from the injector rail with out breaking them. i suspect a hg was done shortly before i bought it, as i found a broken rear exh man stud on the rear of the head and the manifold looks recent or new.
ill hunt thru p n pull tomorrow. lots of vans here locally as smog rules make compliance expensive for non mechanical owners. hope to get another head and shop it. the shop- the only one in town- is owned by an older ex race car driver as you suggested and hes only charging me 125 for the head rebuild job and 40 for the shave. i hope to find that dinky 40 part you refer to at p n pull while hunting for a head. one is without r arms for 60 and another salvage yard has five at 150 each, my choice. so im still sitting good for costs, knock on wood.it could be alot higher.rock auto helps too. thanks - mike

What is the risk if the timing chain fails or breaks? Can the engine be damaged? Ive mentioned to my mechanic a couple of times about my timingchain on my 86 van, he always tells me dont worry about it and its not going to break. Ive got almost 380K on it. He said he is very impressed with the design of the chain on this engine and said not to worry about it.

I also doubt it will break, but it can get loose enough to wear a hole in the timing cover. There can also be performance issues (due to retarded cam timing) if the chain gets too loose. If I had that many miles on an original timing set I'd probably replace it (why tempt fate?). Tim

http://i8.photobucket.com/albums/a23...ps751ce311.jpg

thanks for the responses here. seeing good advice both ways is the best way for me to consider and apply all of the advice shared here.
i have received my timing set from r auto made by clevite. i will install it tomorrow. thanks again for the continued help thru your responses. - mike

Last night I overhauled the cooling system on the van (replaced the thermo, WP, and a recored rad with 3 row high efficiency). - I got curious about a racing sound from the front of the block that i have had since I bought the van. I pulled the distributor cap off, placed the crank at TTC and rotated the crank 7-8 degrees till the rotor turned.:yikes:


Anyone else test the Timing Chain play to determine if it needs to be replaced? I also have been reading into AM vs OEM replacement parts here on the forums and it has me concerned to say the least. I would love to hear what brands of timing chain kits have bee used with good results and no machining required.

Thanks!

So far I've tried Beck Arnley & Engine Pro brand. Both brands had interference issues between the camshaft gear and the bolts and/or washers behind it. Other than that, they both seem to be good quality, but admittedly that in itself is kind of a big deal (certainly pissed me off at the time). On both that I'm running now, I got my clearance by grinding washers and bolt heads (I had my extra sets machined so I won't have that issue next time around). Heres a post I made documenting it: http://www.toyotavantech.com/forum/s...2491#post12491. I haven't tried any other AM brands, but would definitely be paying close attention to these areas if I were to take that chance again. OEM doesn't sell sets, they make you buy everything separately (which increases end cost significantly). Somebody here (BurntBoot I think) purchased all these parts OEM about 3 or 4 years ago and everything was still available (just expensive). Of course machine work is expensive too, so next time I purchase, I'll likely go OEM (if still available).

Having a new timing set will slightly improve performance, but keep in mind the chain tensioner is hydraulic & needs oil pressure to keep the chain tight. Unless I had it apart for other reasons, or had other issues, I probably wouldn't replace a timing set with less than 150k miles on it. I'm not sure I'd push it as far as some, but there are members here who have have gone beyond 300k miles with the original timing set.

The one in the picture below has 380k miles on it. I'm thinking the wear to the housing could have been avoided if it was replaced before 300k. Tim
http://i8.photobucket.com/albums/a23...ps751ce311.jpg

Thanks Tim! My van has 180,000 on it and I am planning a long trip in a few months. So I think it would be a good thing to do on one of my free weekends.

Yeah, at 180k miles it's had a good life. I'd probably replace it too. Good luck, and if you go aftermarket, please let us know how things fit. Heck, a few pics and a short write-up would be awesome regardless of whatever way you go. Tim

Hey Tim , Do you know if the Timing Chain Guides are plastic or metal guides ?

On these old school engines with push-rods & rocker arms, the chains are short, so there's not much in the way of guides. There's just one part called a vibration damper that acts as a guide. It is small and sits on the side opposite the tensioner. It's like a steel bracket with a rubberized coating. Tim

http://i8.photobucket.com/albums/a23...d/IMG_1911.jpg

Ok , wasn't sure if it was like the 79-80 Toyota 20R's that had steel guides or the 22R's that had plastic guides where the chains would wear into them and leave pieces of the plastic guides in the bottom of the oil pans .

Oh I see they are double row chains , that's a plus compared to the single row chains !!!