thralldad

My timing chain broke while I was in traffic yesterday. I was idling waiting for the light to change. I had replaced the chain a couple of years ago with an Engine Builder kit. I'm sure that it wasn't EBs fault as his stuff is great! I wonder if I may have overtightened the adjuster when I installed it.

I guess I have a few options:

1. Slap a chain on there and see what happens

2. find a good used engine and drop in

3. buy a new engine and drop in

Do you think I bent valves?

Lumpy

Bent valves...it's possible. Me I'd open it up check the valves and replace the chain.

tried4x2signN

I've seen a guy break his and he got REAL lucky... It broke, AND STAYED in a position the vales would not hit the pistons...

I'd say a 1:1,000,000 shot, but I wouldn't count on yours doing it...

Remove head, take head to machine shop and get the works (Mine were always $100. Clean, Magna flux, Mill, guides, adjust). Re-install with best, most expensive head gasket, T-chain set and STEEL guides you can afford, drive it till the rings or bottom end gives out...

DeathCougar

iTrader: (23)

slap a chain on it and do a compression test, why not!

tinkertoy

Your question depends on mileage. Also how long you expect it to last. What you do at this point will determine that. If you are just fixing the cheapest way. You may get another 2 years from it. That being top end rebuild and new timing set. At this point you may consider a rebuild for a much longer life. Used engines cost more than a rebuild kit. If you dont have to have machine work done to the block and crank. You can get out for less than $400 on a rebuild. That depends on condition of engine and mileage before the chain let go. Did you bend valves? 99% yes.

PismoJoe

I think if you rebuild an engine you would have the block bored and honed and decked and the crank checked.....or at least I would hope you would

c0ugar69

can you tell what caused the break, is the guide worn? was it the steel EB guide? just curious because I just did a rebuild with one. hope the valves arent bent, put new chain and test compression.

thralldad

Mileage is 206K. I used EB kit with steel guides. EB stuff is highly recommended. If there is a problem it's probably me on the install!

I plan on keeping this truck forever. I won't be able to tear into it until next weekend. MTF

PismoJoe

Just curious, what was the mileage when you replaced your timing components?

thralldad

195K-ish? I was deployed so the truck was only driven once a month for a year. I started driving it regularly again in March.

tinkertoy

Did you remove the oil pan when you changed the timing kit? I would bet on a clogged oil passage to the adjuster. Most used Toyotas are not welll maintained. Due to the story that they last forever. Folks think you dont have to maintain them as well. Wrong. Timely oil change is the key to making 400K on a Toyota. Along with tune ups. Gas additives like Lucas or sea foam, help against carbon build up. Gas now days sux. Dirty and not up to specs. So , I would guess its rebuild time. Lots of things to know, not in the Haynes manual. If you do rebuild. I could write a page or so on must do on 22rs that seldom get done on rebuilds. Even with some rebuilders.

thralldad

I'm the second owner and I know the service history before I got it and the last 100K I've changed the oil every 3K. I checked the chain for slack when I adjusted the valves last month. I have started using semi-synthetic the last couple of oil changes in an attempt to boost mileage a bit as I drive 80 miles a day. Could that have possibly caused a problem? It just passed emissions with excellent results!

PismoJoe

Synthetic oil wouldn't cause your chain to snap. Do you think that you might have over tightened the oil pump bolt that goes all the way through? If you screw this in far enough, it can make contact with the tensioner causing timing component failure very early.

thralldad

I will have to check but I was very careful because I know there are different length bolts. I suspect I may possibly have overtightened the adjuster if anything. This wasn't my first R & R. I mentioned synthetics because of their higher detergent qualities. I'm working this weekend but I will tear into ASAP. Thanks for the responses!

tinkertoy

Did you have a problem installing the cover. Like having to pull the cover tight with bolts, instead of it just snugging up tight pushing it on? I have a reason for this question.

thralldad

No the install went smoothly as I recall. The only thing that I could think of was that I must have overtightened the adjuster bolts. What were you thinking?

PismoJoe

Did you use a torque wrench? had to ask....

Kiroshu

Could have got a faulty part... it happens... usaully after market timing chains only have a one year replace if defective i believe... On most... Do you dog it out? High revs and hard take offs? Over tightening the tensioer i don't think would have anything to do with the chain to break... Something happened inside. The chain either was poor quality and stretched pre-maturely and broke or it got hung on something and broke...

What was your diagnosis on the broke chain? How do you know? Compression check? Engine spin over very fast? Remove valve cover?. If its broke you might as well remove the head and check the valves...

The sythetic blend is good and nothing to do with it but i recommend you not go to full sythetic as since the engine is used to and made for conventional oil it may blow out some seals....

tinkertoy

Here is something I found. Bought the timing set from Engnbldr. I installed the steel timing guide set. I then tried to replace my timing cover. It would not push up flat with the steel guide installed. It was holding off maybe .020". I emailed engnbldr. He said sometimes the steel guides had to be fitted. Filed out the top bolt hole a little and, bingo. Perfect fit. Had I just tightened it up, it would have went but would have bent the guide inward and that could soon become a problem. Just something to think about. Remember they were not built for steel guides to fit. Thats an aftermarket add on and likely a good cure from stock. I havent had one go 135K on an install yet, so I cant say yes or no. It just seems logically like it may be a cure for the breaking plastic guide. I did tighten the adjuste to much once and the knock was immediate when cranked. Lesson learned. 12 LBS only, no tighter. Then make sure it pushes in and out easily. Then tape it closed to make chain install easier.
Make us a picture of what you find in the oil pan. When you tear it down. Yes, I would look in the oil pan and make sure I get everything out of it. I have seen tensioner tips break off and cause the chain to break. Just saying.
You can guess, and we can guess, But the proofs in the engine. Tear it down and look. Let us know what you find for future reference.

flyingbrass

x2 on checking clearance when using a steel guide. My steel guide, when adjusted as it looked best, prevented the cover from fully seating. https://www.yotatech.com/51359046-post258.html