600ccs

I have 1994 4Runner w/ 3.0 V6 w/ hydraulic timing belt tensioner.

So I replaced the timing belt, water pump, both pulleys, etc. After assembling enough of the front of the engine to see if it will start, went to start it. Engine fires and dies after 2-3 seconds and the timing belt jumps teeth.

The hydraulic tensioner checks out to be plenty strong.
The crank, the cam pulleys, and the belt marks are lined up. Maybe not to NASA clearances but all seems right.

I'm stuck. Don't know what is up?? I've reassembled it 20 times and I don't understand why the belt jumps and engine dies?

Anybody wanna guess?
Thank you ,
Brian

darkmourning

which way are the triangles pointed on the belt? they should be pointing towards you. i know it sounds stupid but check it, if it's the wrong way then flip the belt and try it again.

blake.nemitz

sounds like too much play in the idlers and if the tensioner isnt coming out far enough it will cause problems. got a seizing cam or something stuck in the wp

Swim

Ok, here's how I do it.

Pull timing belt back off.

Take the driver side cam 2 teeth to the right (when looking at the engine) and hold it there. Now take your belt and pull it tight around the cam pulley, rotate it to the left 2 teeth and you'll be lined up at the top. The idea here is to use the cam pulley itself to pull the extra slack out of the timing belt on that side. Now do the same thing on the passenger side one. This will leave all the slack for the tensioner to take up. Adjust the tensioner, and tighten the bolt.

Make sure you rotate the engine with the crank bolt 2 times before starting.

600ccs

Thanks for the reply. Did do something like this already but I'll do this exactly. Again thanks.

600ccs

darkmourning, thx for the reply. yea got the belt arrows pointing forward to front

600ccs

blake.nemitz, tensioner seems fine. wp spins smooth but tight like new one should i'm thinkn. that seizing cam idea has me thinking though. but i turn them by hand and they seem to spin ok. they are supposed to spin, resist, spin, resist, spin, resist correct?

zlathim

You do know that the lines on the belt are there for set-up purposes only, right?

Once you turn the engine over, the lines on the belt will not line back up, and that is normal. As long as the marks on the pullies line up, the lines on the belt mean nothing, after initial timing set up.

I'm not sure if this is what is going on, but I wanted to make sure you understood that before going any further.

600ccs

What? I assumed the lines on the belt would maintain position after turn over. But now I can see changing position since you have different pulley diameters in the system.

Then maybe the reason for the engine dying has to do w/ something else completely? I don't have much of the front of the engine assembled when trying to test it out. Problem could be vacuum related? I did have the alternator hooked up a few times.

Team420

ya didnt forget to reconnect the afm did ya? Just askin cuz I am dumb sometimes, and I spent an afternoon once, trying to figure out y my rig would start, then instantly die... sure enough, I forgot the 2 second job of reconnecting the afm....

Stupid... maybe.... but I got to spend an extra 6 hours drinking beer and hangin with friends as a result....lol

600ccs

Got the truck running last night!!! Happy as hell. Turns out I just needed to assemble everything and connect ALL vacuum lines. I had the belt on correct after all. Thought I had it right but didn't like the looks of it. Thanks zlathium! And thanks to everybody for the responses here. Got a lot of help here for sure. Next projects... passenger side valve cover gasket, tranny fluid change, buff the paint out

darkmourning

z- yeah that is true, but the way the triangles on the belt face can make a difference. it helps get the right slack in the belt when you put all the pullies back on and lines up the timing marks correctly. thats what i was talking about. cause if he was putting the belt on backward and trying to line up the marks then he woulda skipped a tooth or two when it started. ive had it happen to me when i was a young line tech @ toyota.

darkmourning

good job! glad you got it runnin again. now go have fun!