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Discussion Starter #1 (Edited)
Been having a hell of a time with Toyota tensioners & belts on my Gen2 build. I had two tensioners go out, both within 1000 miles. I replaced the oil pump to one from a 2000 5SFE, the oil drive gear has 25 teeth...this would mean I would have to use the Gen3 177-tooth timing belt, correct?

The belt has enough slack to almost pull it off of the gears. I even replaced the adjustable gears with my factory ones, just in case. I searched on the forum and came up with using the Gen3 belt when on that 25-tooth gear...thing is, my previous oil pump had 25 teeth as well, and did not have this kind of slack when I got the timing done.

I currently hear a "slapping" or "knocking" on the timing side. At first I thought it was the piston doing it, but I eliminated that by pulling each plug wire until the sound went away...it didn't. I checked timing and it's currently 1 tooth off on the intake side, must have jumped with all the slack in the belt...this explains my boost issues as of late. Just wanted to be 100% sure before I tear into it again and start replacing gears/belts. Any input is welcomed!

EDIT: See Post #15 for results!!

 

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I could be totally wrong here, but I am having a hard time figuring out why the number of teeth on the oil pump will effect the number of teeth required on the timing belt. The oil pump isn't timing related, and the number of teeth on the belt is purely a function of it's length (it's not like the belt has to go around exactly one rev in a certain number of engine revs).

The only critical tooth counts should be that the crank pulley has half as many teeth as the cam pulleys. Other than that, the tooth counts on the oil and water pumps will effect how fast they turn, but shouldn't necessarily effect the required tooth count on the belt.

With the amount of belt slack you are describing, it sounds like the belt is too long for the amount of throw available in the tensioner.
 

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Well...I never go against the BGB normally.. but when it comes to the tensioner I do not follow that procedure they do with the feeler gauge. I get all the slack out of the belt then I push the tensioner as far as it can go..tighen it up then pull the pin/allen wrench. I've been doing it that way for years and never had a problem yet. Just so ya know.
Yes..Alex is right. It doesn't matter how many teeth the oil pump has unless the pulley is so small that its putting slack in the belt. And in that case it must be a custom pulley. Or as Alex stated..the belts to long.
 

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Well...I never go against the BGB normally.. but when it comes to the tensioner I do not follow that procedure they do with the feeler gauge. I get all the slack out of the belt then I push the tensioner as far as it can go..tighen it up then pull the pin/allen wrench.
I forget the year that it changed, but the early tensioners have the slotted holes, and the above adjustment procedure. I don't know if that procedure appears in the later BGB, but the tensioner part number superceeds at some point to one that has normal round holse, so there really isn't much adjustment available.
 

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Discussion Starter #6
My tensioner(s) had slotted oval holes for some minor adjustment, although I have already tried to move it closer, it's as far as it can go. I performed the same procedure that mike555 did, but the more I read up on the board the more I see that same piece of information about using that belt. Just want that confirmed, otherwise my brand new timing components are failing...for the 3rd time :/
 

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My tensioner(s) had slotted oval holes for some minor adjustment, although I have already tried to move it closer, it's as far as it can go. I performed the same procedure that mike555 did, but the more I read up on the board the more I see that same piece of information about using that belt. Just want that confirmed, otherwise my brand new timing components are failing...for the 3rd time :/
Just to be sure...But you do have the plate washer behind #1 pulley..dont you????
 

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I run the camery oil pump on all my builds.. cause its a bit higher out put...(a bit smaller pulley) But its never put slack in the belt. You are using a toyota tensioner?
 

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Once you pull the tensioner pin...then crank the engine over by hand a few times..that belt should be pretty dame tight.
 

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Discussion Starter #11
I run the camery oil pump on all my builds.. cause its a bit higher out put...(a bit smaller pulley) But its never put slack in the belt. You are using a toyota tensioner?
That's the same pump I am using from a 2000 Camry, the pulley I mentioned is the 25-tooth just as you said. Toyota OEM timing components, always. Yet, they have failed me numerous times already (No.1 Idler Pulley, Tensioner)

Once you pull the tensioner pin...then crank the engine over by hand a few times..that belt should be pretty dame tight.
Thing is, it was tight. Cranked it a good dozen times to make sure. About 30 seconds into startup the "clicking/slapping" sound comes up, turn off the car and the slack is there...but it moves around. Sometimes on the water pump side, top of the gears, or none at all (I assume because the slack is further below, which I can't see).
 

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I've never had a tensioner fail on me yet. knock on wood! Its gotta be the wrong tensioner or the wrong belt. Just for the record you need to run the gen 2 belt. not gen 3! If every thing is stock but the oil pump? use the gen 2 belt.
 

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Discussion Starter #13
My money is on the wrong belt, I do have a Gen3 belt here to try just gotta muster up the courage to tear into the timing AGAIN...ugh.
 

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Have you gotten anywhere with this yet? I've got a very similar situation happening on my '91. I put on a new belt and all new pulley's and tensioner and at about 2,000rpm I've got a hell of a rattle/knock/slap thing going on. . We pulled it all out and moved the tensioner farther to the right (I have the slotted hole version) and it didn't fix the problem. Also the person helping me (who has lots more experience with timing belts than me) thought the belt was a bit too loose even after rotating the motor over by hand a couple times once it was all back together. I'm looking at pulling the motor back out now to tear it all down again and look for the issue.

Also what's the deal with the washer on the pulley, I'm not sure I've heard about that and I'm wondering if I messed that part up?
 

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Discussion Starter #15
Gen3 Belt Works

Man do you have awesome timing, I JUST did the belt swap yesterday and was gonna post about it later lol.

100% Confirmed the Gen3 177 tooth belt works with the 25 tooth oil pump gear.


If you have the 27 tooth version your belt might be stretched already and that's why you have slack. My High Volume pump came with that 25 tooth, so the Gen3 belt would be your fix if that's the case :smile2:
 
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