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Sigh.. leaking tensioner...

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Old 12-07-2013, 02:30 PM
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17prospective buyer
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Default Sigh.. leaking tensioner...

So I rebuilt my tensioner, fine. All went according to plan. So I filled it up with gear oil using the fill and bleed screws. It is SO slow to fill with the tiny holes in those bleed screws, course it didn't help that I work in an unheated shop where it was -10 at that point in time. So eventually I got impatient and just poured the gear oil in the little sections where it mates to the block, sure enough it filled. Then I thought I was good to install it. So I applied some RTV to the perimeter of the gasket that will see oil contact, just to be sure. Bolt it on and torque all the bolts to 20nm and I have what appears to be a very slow leak, like maybe a drop a day, right at that bottom bolt where I assume all the gear oil pools. What do I do? I made sure the aluminum mating surfaces were cleaned of all the old gasket material with a razor. I'd rather not have to order another gasket. Was the RTV a mistake?
Old 12-07-2013, 02:39 PM
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69gaugeman
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Don't worry about it too much. Probably 90% of the tensioners out there have no oil. Next time you are bored and need to go in there and fix it. Or not. Your choice. RTV is almost always a mistake. Unless designed to use it, it should be avoided.
Old 12-07-2013, 05:09 PM
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Mrmerlin
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when installing the tensioner here is how I do it
When you rebuild tensioner use a new boot,
put some Loctite PTFE sealant on the adjuster bolt threads,
and also on the one bolt that goes into the oil return port on the block
make sure the inner U boot clamp has the open end facing up.
Note outer clamp will have the crimp section at about 11 O clock when looking at it from the boot side.

Make sure both mating surfaces are clean use Hondabond 4 on both sides of the gasket. install the tensioner.
Use a visene bottle with the tip drilled out a bit so oil can flow,
fill this bottle with STP oil treatment its thicker than gear oil.
after the belt is installed fill the tensioner,
remove both nipples,
fill from the port closest to the right fender,
the port closest to the crank is the vent ,
when oil comes from this port its full .

install the nipples with some PTFE on the threads
Old 12-07-2013, 05:26 PM
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17prospective buyer
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Thanks Stan, might actually go with a Porkensioner now though. After reading about how the loss of oil is common, and how many problems a tensioner can cause if everything's not exactly right. Since I haven't even tensioned the belt with the rebuilt components I could just sell the entire assembly to someone who wants a bolt in tensioner job. Not worth the effort to risk destroying the rollers to take them off and sell it all separately. Without special pullers and such I don't think there Is a non destructive way to get the smaller roller/pivot bearing off once it's been put on.
Old 12-07-2013, 08:13 PM
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all of the bearings can be pulled off without damage if you have the correct tools drain the block before you remove the pivot bolt
Old 12-07-2013, 08:27 PM
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17prospective buyer
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I have a new Laso water pump on there, which just uses an allen head screw. I'll just sell the whole tensioner assembly as a unit when I get the Porkensioner. Stan I have to say I love that color! So delicious looking. Is that original paint? Perlglanz paint was rare and all custom wasn't it?
Old 12-07-2013, 09:54 PM
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This car has original paint and interior,
its a rather stunning color in the sun
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Old 12-08-2013, 12:52 AM
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Many at Frenzy were commenting on the paint on Stan's car, especially the apparent depth. It's very unique. Must be seen in person to be fully appreciated.
Old 12-08-2013, 11:43 AM
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Originally Posted by 17prospective buyer
...just poured the gear oil in the little sections where it mates to the block, sure enough it filled. Then I thought I was good to install it. So I applied some RTV to the perimeter of the gasket that will see oil contact, just to be sure. Bolt it on and torque all the bolts to 20nm and I have what appears to be a very slow leak, like maybe a drop a day, right at that bottom bolt where I assume all the gear oil pools.... Was the RTV a mistake?
Pre-filling it this way makes it pretty hard to get the back of the tensioner clean enough for the RTV to stick, so it probably didn't. But I am not sure that matters, because the gasket has a molded silicone bead around that area.

I'm starting to use Dreibond at GB's suggestion, not cheap but seems like really nice stuff. I particularly like the comment on the label that "oil assists curing". That's my kind of sealer

The leak is most likely through the adjusting-bolt threads, it needs some sealer. PTFE pipe-thread paste is good, or your favorite gasket sealer. Just put it on the threads, tightening the lock-nut will seal it.

Follow Stan's advice and it should be good. Warming the oil will help also.

I am not convinced about using STP, though. The purpose of the oil is to aid heat transfer and provide some damping in conjunction with the check-valve in the bottom piston. If the tensioner is properly sealed then it won't leak, if not then it will eventually leak no matter what oil is used.

Originally Posted by 17prospective buyer
Thanks Stan, might actually go with a Porkensioner now though. After reading about how the loss of oil is common, and how many problems a tensioner can cause if everything's not exactly right. Since I haven't even tensioned the belt with the rebuilt components I could just sell the entire assembly to someone who wants a bolt in tensioner job. Not worth the effort to risk destroying the rollers to take them off and sell it all separately. Without special pullers and such I don't think there Is a non destructive way to get the smaller roller/pivot bearing off once it's been put on.
This is false security, I think. Any belt system can have problems if everything's not exactly right, irrespective of the type of tensioner. The trade-off is the convenience of not having to adjust it, versus having an alarm to monitor tension if anything goes wrong. The fact that the PKT is self-adjusting is a double-edge sword: It happily accommodates thermal expansion but is just as happy to accommodate something falling apart, not complaining in either case. So the need for periodic inspection, and to keep an eye on things, is no different.

The plastic pivot bushings are a light press fit into the tensioner arm, but should slide on and off the shaft without any drama.

Cheers, Jim
Old 12-08-2013, 12:50 PM
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Still leaning towards the Porkensioner, I like the simple eccentric cam style actuation of the tensioner. I rebuilt the entire arm with new bushings and all, the press fit of the smaller roller bearing is tricky because you need to push it off using the bearing itself, if you just press on the roller the roller itself will just slide out of the bearing. No matter. I'll sell all that stuff as one unit. I rebuilt that whole assembly with all the recommendations. New rollers all around, o-ring for tensioner, new boot and crimp style clamp. I don't want to sound like a corny testimonial for the Porkensioner but what I would repeat here is basically all that is said about it on his site. I agree with the simple way it works, and other manufacturers have managed to have drama free timing belt tensioning systems for years. Now I know that those are mostly 4 cylinders with less complications that need to be factored in. But I had a 98 Corolla 5 speed beater for a couple years that had 420 000KM on it when I sold it, and I honestly don't think the belt was ever changed, none of the motor was ever even opened up in it's lifetime. Needed a valve adjustment, but it just ran and ran and ran.
Old 12-08-2013, 01:50 PM
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Or is it leaking out the bolt and dripping off the bolt? I don't like how they seal the back.

I'll use a thin coating of gasket maker on the tensioner gasket if the surfaces look bent or uneven. The RTV wasn't a "mistake," I don't think.

I see you torqued it right. Overtorque can make the victim part bend.

In any case, I wouldn't worry and I'd leave a repair until it was convenient. Maybe top it up occasionally. The oil lubes the mechanism but there'll be surface coatings if it all runs out.
Old 12-08-2013, 01:56 PM
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I noticed the little bead of another material that is embedded into the gasket as it is, but figured RTV won't hurt. I think it's because I filled it using those segments on the back of the tensioner, so the surface got wet with oil as soon as I flipped it 90 degrees to mount it on. I had a bunch of bolts replated and I just keep selecting the ones I need out of the pile based on measurements, discovered the PET must be wrong in the bolt lengths. It states I think 2 55mm M8's for example, and 55mm barely comes through the back of the tensioner, maybe like 3 threads showing. So I knew that must be wrong.

Says: 1x M8x60 for the bottom-most bolt-way too short
1x M8x45, way too short
2x M8x55, still way too short
Old 12-08-2013, 04:03 PM
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Originally Posted by 17prospective buyer
Still leaning towards the Porkensioner.
this
Old 12-08-2013, 10:20 PM
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Originally Posted by LT Texan
this
Or not.
Old 12-10-2013, 11:30 PM
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Originally Posted by 69gaugeman
Or not.
Yep. Your choice. I know mine.


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