Itoyota

lets see what the community has to contribute.

I am not aware of a spec for tolerance for the driver side timing guide. I went chasing a coolant leak that's finding it's way into the oil and I came across a large amount of play in the driver's side timing guide. The top bolt that holds the guide is tight against the block, but the guide an easily be moved perpendicular to chain direction about 1/4 inch.

WHAT"S UP WITH THAT?!

abecedarian

timing guides (driver or passenger) should not move at all.
that's your tolerance

abecedarian

next thing is the guide itself breaks (or is chewed up by the chain) and falls into the oil pan and allows the chain to slap against the timing cover.
after that, the chain wears into the timing cover and causes coolant to flood into the oil pan.

thook

Or, the guide pieces fall into the crank gear/chain assembly, throws or breaks your chain, and then you slam one or more valves (usually more) into the pistons.

The guides are wearing/worn out. Replace your timing kit right away. Do not driveth the vehicle!!!!

Unless, you want to rebuild the head.????

(And, I'm not being an alarmist.)

abecedarian

and upon receiving confirmation of the failure of the guides which control combustion, the common people rejoiced.

However they were met with consternation and confusion... for they were not forthwarned of the potential hostile future into which they would live.

One would assume that fixing the problem would be fortright, but nay... sometimes it is for naught.

thook

When a man findeth upon his side a wretched thorn, haste he must not to removeth the offender and correctuth injury thus far sustained For upon his procrastinous folly, verily he shall find malady of a gangrenous nature of which unquestionably entails a dismemberment of the affected...uh.....member.

You must be up late and bored, too.....meh.

ovrrdrive

That's exactly what happened to me on a rebuilt engine that only had 8k on it. Once the guide shatters it's too late. I think I spent about $800 to fix it myself.

thook

Yes. I remember those pics of the valves.....

Itoyota

yeah well the valves are safe. I heard the deisel rattle and drove it straight home and tore it apart. So, since the timing set was just done less than 10k miles ago ... i'm a little PO. But whatever live and learn. No more aftermarket parts. I'm buying the toyota guides.

thook

Oh, good that you checked into it right away, then. Wish I had.

Itoyota

Like i said, you live and learn. When i first got my YOTA I had no experience with engines. It took me awhile before I worked up the courage to open the valve cover and join yotatech to find out that the timing chain had already begun to eat through my timing cover.

ovrrdrive

Did you consider the engnbldr steel backed drivers side rail?

A lot around here are running it including me with good results. there's no chance of it failing at all. I highly recommend it.

874runnersr5

x2 on engnbldr timing chain guides.

abecedarian

for the most part when you see things broken or wearing, even if there are no symptoms of the failure,they need fixed.
as for the guides' bolts, only tighten them as much as necessary to hold the guide and a little drop of blue loctite will hold them in place.. until you wrench them loose to replace the guides next time.

abecedarian

and I 2nd the engnbldr guides, though I'm not using them. steel in the guide will help keep the chain from contacting the timing cover. the main drawback though is that without that audible warning, it's almost impossible to tell the chain is wearing out and needs replaced. So, stick to the 70-100k max mileage recommendation to replace the chain and guides, which is arguably the max the plastic guide lasts.

thook

The plastic layer over the steel guide isn't very thick. Maybe 1/8" at most. So, if one's chain has worn through that and no audible sign is apparent.......on STEEL.....something is wrong. Unless, your deaf. Then should you really be driving?

Tool Pants

I have a 1988 22R with 157,000 miles. I have owned it since 1989. The only part that has been replaced is the front oil seal because it was flinging oil. And I confess, the valve cover has never been removed. That is right. The valves have never been adjusted.

I know about those plastic chain guides. From what I have read when the guide breaks I will hear the chain rubbing against the cover to warn me it is time to replace them. I have no such noise.

I have thought of replacing the guides and chain as preventive maintenance. Then on the other hand, my lazy hand, I though I should just keep driving and wait until I hear the noise.

What is the rule of thumb on how long these guides last? If I remove the valve cover will I be able to see enough of the guide to check the condition?

874runnersr5

Yup, remove the valve cover, get a flash light and check if the chain has any slack... and so on.

87LVRunner

Interesting that you all say that the guides should be tight. When I took my engine apart, the guides have a small amount of play in them to allow for self adjustment. When pulling the bolts off that hold them on, you can see that the bolts are smooth so you cannot over tighten and not allow play. This was the same on my 85 truck, 85 Runner, and this 87 Runner. When I put the new guides on and tightened the bolts down, the guides still move a little. Hmmm...

89whitetoyota

If the crank and the cam are in the same position when you take the old timing sh_it off, then just match the bright colored timing links on the chain with the dots on the top and lower sprokets and put the guides, do you still need to time the motor? I mean i know the distributor will come out, but I could prolly mark that, I just dont want to have to do the TDC if I dont have to.