jyou9

Just put a new engine in my 87, 22r I bought some time ago from a member. Engine had 800 or so miles. Brand new head installed with old cam, cam was fine. Old rocker assembly used, still in good shape. Fired it up, timed it, drove 5 miles down the road and cut it off. Started it back up, ran for 2 seconds and died. No spark. Towed it home, pulled the vc and found a broken timing chain. Any thoughts of why? Didn't see any broken links...I'm sure the head is toast, I'll probably throw the old one back on. My question is...is there anything else I should look for or do before trying this again? Obviously I will get a new chain, and that chain was pretty much new, but what would cause it to break?

wyoming9

iTrader: (1)

What was your oil pressure like??

There has to be a back story here.

I am thinking it was a new engine to you not a new engine

Was a new timing chain kit put in with new tensioner ??

About the only way a chain can break if it was new is to get way to much slack jamming at one of the sprockets then the weak link broke.

New or old chain it got way to much slack.



tensioner did not get enough oil or failed in general.

The chain was not replaced was old and tired.

This had to have made lots of noise when this happened.

Only looking at the engine real close may shed some light on the issue.

Terrys87

iTrader: (1)

Like Wyoming mentioned, I cant see it breaking without getting caught between the timing cover and crankshaft or something similar. I have installed a chain and it slip off of the crank shafts teeth and look normal with the head on. I wonder if something like that didn't happen to you, had you thinking everything was on right. When I install a chain now and have the head off, I zip tie the chain around the camshaft sprocket until I am ready to install the head.

You cant see it but there is a zip tie at the bottom of the camshaft sprocket.

jyou9

So....truck doesn't have an oil pressure gauge. Chain, guides, and tensioner looked new, but I didn't put those in so I can't guarantee that. I did inspect them, they appeared to be ok. No noise at failure, like I said, it broke at idle...seriously confused and slightly pissed...

ZUK

iTrader: (1)

Wonder if worn sprockets would do something like that.

wyoming9

iTrader: (1)

Was the break jagged and messy.

Or was it possible one of the links popped off and it just fell apart then jammed ??

One of those things I would love to see in person

Were both the sprockets on ??

Does every thing turn free now that every thing is off.

Cam and crank both turn smooth.

Old cam New head I wonder if the Cam seized and broke the chain. Brand New Head or used head.??

Was the Cam gear broke off the cam??

Sprockets They would really need to be worn.

Then the tensioner should take up the slack.

jyou9

Wow that's allot of questions...what I can tell before the tear down is the timing chain broke pretty clean, almost as if the link gave out. As far as the head goes, it was brand new, as were the timing chain and common components. I haven't tore anything down today, spent three days building that damn engine and I'm kinda tired of looking at it to be honest! Cam looks fine from what I see with the valve assembly still on. Crank moves free, can't feel anything drag or restriction and there is oil in the head so I know the pump was functioning...I will keep this thread updated as I tear into it, and try to post any pics if I can figure out how to do it from my phone. As always, I appreciate y'alls help on this one, there is so much knowledge on this site that I almost feel overwhelmed asking dumb questions! If I say anything stupid, just remind me that I'm a noob and I need to be more specific.

snobdds

All the aftermarket chains I've seen are not the same quality as an OEM Toyota chain. There really is a difference and I would suggest putting an OEM tensioner and Chain on. Get the metal backed guides though, not the plastic OEM ones.

Something happened and once you open it up...you will find it. Let us know...

Terrys87

iTrader: (1)

Don't worry about being a newbie. Open a Photobucket account and from your smart phone you can send a picture straight to Photobucket or from a phone you can send it to your email and then transfer it to Photobucket.

If you click on the Quote button in the picture I posted, you will see the picture in text form [IMG]...[IMG] , it will be the bottom option/4th in Photobucket that you will want to copy and paste into your post.