'89 4x4, 22RE.

Engine was rebuilt 2500 miles ago, parts were all replaced using EB stuff <img src="/forums/images/graemlins/kewl.gif" alt="" /> However, ever since the rebuild, I get chain rattle ONLY during startup. Goes away as soon as oil pressure builds. The motor was such a mess before the rebuild, I don't really have a 'normal behavior' to gauge against. Is it normal to get a bit of chain rattle during startup before there is oil pressure?

The only think I can think to mention is that I have been using purolator oil filters, not OE Toyota filters. I picked up an OE for the next oil change (which I'll be doing when I tear it all apart again to replace the head gasket - but *sigh* that's another thread...).

Do the OE oil filters maintain oil pressure so that the tensioner is keeping tension on the chain even when the motor isn't running? I wouldn't think so, or oil would spray out when you remove the filter... right?

Any ideas? Tensioner was new when installed, and I made certain the correct bolts were used on the oil pump so the tensioner should be fine, and seems to do its job once the motor is running and pressure is there.

Some noise during startup is normal.
The stock oil filter has an anti-drainback valve.
It doesn't hold oil pressure, but it does keep the filter full of oil so the pressure builds back up faster.
Some aftermarket filters have these, some don't.
Hard to tell if your noise is typical or not.

what did you torque the bolts holding the tensioner on upon installation? they are only supposed to be set to 12 ft. lbs. over torquing will damage the tensioner preventing it to fully retract. or you might have a faulty tensioner, which is pretty common. i suggest you call up eb and let him know about your problem, if the tensioner is actually faulty(idk how to test it) im sure eb will be glad to send you another one.

i'd try swapping out filters first. but purolator actually makes really good filters, unless you have been using the really cheap ones. i was actually told that toyota gets their filters from them and puts their name on them.

also are you positive it's the tensioner? it might be your bearings going bad. how many miles are on the truck?