What is The Name of This Component?

[Guest]

As I was removing the intake boots I had to remove this to get to the lower phillips screw on the number 3 boot. I was a little rough with it and half of the gasket stayed behind when the part came of the block. Can anyone tell me what this is so I can start searching for a new gasket? Looks to be some kind of relief valve maybe?

1983 GS850L

[Cipher]

What is this thing Called Love?


That is the cam chain tensioner.

[Steve]

Without any other commentary, yes, it is the cam chain tensnioner.

When you put it back on, follow the instructions VERY carefully.

.

[chuck hahn]

Yeah...that didnt need to be jacked with. Better read the service manual and follow installation directions. AND VERY IMPORTANT....DO NOT move the crank one smidge until tentioner is back in.

[DevoutClient]

Yikes. So is this a "just put it back without breathing on anything" situation or do step 13 described here: https://www.bwringer.com/gs/camchaintens.html or am I well and truly #*$%ed and need to do a full timing exercise? I have not adjusted, or messed with anything other than removing the 3 mounting bolts and pulling the tensioner unit away from the block. The transmission has been in neutral and the crank has not been moved.

I'd really like to avoid taking anything else apart at this point (maybe should have considered that earlier)...but if I have to pay the stupid tax, so be it.

[Cipher]

Yikes. So is this a "just put it back without breathing on anything" situation or do step 13 described here: https://www.bwringer.com/gs/camchaintens.html or am I well and truly #*$%ed and need to do a full timing exercise? I have not adjusted, or messed with anything other than removing the 3 mounting bolts and pulling the tensioner unit away from the block. The transmission has been in neutral and the crank has not been moved.

I'd really like to avoid taking anything else apart at this point (maybe should have considered that earlier)...but if I have to pay the stupid tax, so be it.

If the engine has not been disturbed bolt it back in place.

[Steve]

Item #13 is accurate, but leaves out the emphasis on the most critical part.

It mentions releasing the plunger by turning the set screw 1/4 to 1/2 turn. That is good, but I have seen problems with stopping there. Examination of the mechanism shows that there is a notch in the plunger where the set screw sits. With the screw out just a fraction of a turn, the plunger can slide past the screw, but the end of the notch will prevent the plunger from going all the way into the engine if the chain wears past its limit. Some screws can be pushed IN past the other end of the notch, so the set screw will actually lock onto the outer circle, not the notch. If you simply release the screw and lock it in place, there is no guarantee that it is in the notch.

To ensure proper installation: release the plunger, watch the large knurled knob to see that it turns. Turn the set screw IN until it stops, THEN turn it out 1/4 to 1/2 turn and lock it in place with the lock nut. Only takes about 5 seconds longer, but will ensure proper installation.

.

[GSXR7ED]

Good info on here...I have replacement parts for my tensioner...but I have not proceeded with any action to remove it.

Ed

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[bobgroger]

Or replace it with an APE mechanical tensioner. http://gszone.biz/tensioners.html

[hannibal]

Item #13 is accurate, but leaves out the emphasis on the most critical part.

It mentions releasing the plunger by turning the set screw 1/4 to 1/2 turn. That is good, but I have seen problems with stopping there. Examination of the mechanism shows that there is a notch in the plunger where the set screw sits. With the screw out just a fraction of a turn, the plunger can slide past the screw, but the end of the notch will prevent the plunger from going all the way into the engine if the chain wears past its limit. Some screws can be pushed IN past the other end of the notch, so the set screw will actually lock onto the outer circle, not the notch. If you simply release the screw and lock it in place, there is no guarantee that it is in the notch.

To ensure proper installation: release the plunger, watch the large knurled knob to see that it turns. Turn the set screw IN until it stops, THEN turn it out 1/4 to 1/2 turn and lock it in place with the lock nut. Only takes about 5 seconds longer, but will ensure proper installation.

.

I recently spent some time examining the tensioner to find the source of a rattle in my motor. The process listed in the manual is correct and sufficient, and I don't agree with the additional steps you outline.

With the set screw backed off "a fraction of a turn", the end of the set screw sits in the notch on the plunger and the plunger is free to move against the chain. I believe this is sufficient to maintain tension on the chain as intended. While it is true that backing off the set screw even more will allow the plunger to move over a larger range of motion, this is unnecessary. If the plunger needed to move such a large distance to keep tension on the chain, the chain would be FAR beyond its service limit. I don't think a chain could remain intact if it were to be so long that the plunger needed such a large range of motion.

In short, I've concluded that the set screw should remain in the notch on the plunger once the set screw is loosened 1/4 to 1/2 turns. If the plunger was designed to move over such a large range, there would be no need for the large exterior knob or the notch on the plunger. After the pushrod is extended more than 1-2 cm from fully compressed, the notch is no longer near the set screw, the big exterior knob is no longer interacting with the plunger, and only the spring on the plunger is providing tension on the chain.

[mrbill5491]

I recently spent some time examining the tensioner to find the source of a rattle in my motor. The process listed in the manual is correct and sufficient, and I don't agree with the additional steps you outline.

With the set screw backed off "a fraction of a turn", the end of the set screw sits in the notch on the plunger and the plunger is free to move against the chain. I believe this is sufficient to maintain tension on the chain as intended. While it is true that backing off the set screw even more will allow the plunger to move over a larger range of motion, this is unnecessary. If the plunger needed to move such a large distance to keep tension on the chain, the chain would be FAR beyond its service limit. I don't think a chain could remain intact if it were to be so long that the plunger needed such a large range of motion.

In short, I've concluded that the set screw should remain in the notch on the plunger once the set screw is loosened 1/4 to 1/2 turns. If the plunger was designed to move over such a large range, there would be no need for the large exterior knob or the notch on the plunger. After the pushrod is extended more than 1-2 cm from fully compressed, the notch is no longer near the set screw, the big exterior knob is no longer interacting with the plunger, and only the spring on the plunger is providing tension on the chain.

These folks know what they are talking about, nuff said.

[Cipher]

These folks know what they are talking about, nuff said.

Yes how dare he allow his actual observation of a system sully the reverence you think we should have when folks here are off the mark.
NUFF SAID?? Good god!

[posplayr]

Without any other commentary, yes, it is the cam chain tensnioner.

When you put it back on, follow the instructions VERY carefully.

.

Someone is too lazy to look in the FSM.

[Steve]

With the set screw backed off "a fraction of a turn", the end of the set screw sits in the notch on the plunger and the plunger is free to move against the chain. I believe this is sufficient to maintain tension on the chain as intended. While it is true that backing off the set screw even more will allow the plunger to move over a larger range of motion, this is unnecessary. If the plunger needed to move such a large distance to keep tension on the chain, the chain would be FAR beyond its service limit. I don't think a chain could remain intact if it were to be so long that the plunger needed such a large range of motion.

I mention the extra step for one reason.

I have seen the setscrew loosened beyond the depth of the notch when the plunger was retracted for installation. This means that when it was tightened to lock the plunger, it was on the round part, OUTSIDE the notch. If, after installation, you only backed off the set screw the usual 1/4 to 1/2 turn, then locked it in place, you would be locking it at a point that was OUTSIDE the notch.

After loosening the set screw after installing the tensioner, turn it back IN. If it only goes 1/4 turn or so, you were probably in the notch already, so just back it out 1/4 to 1/2 turn and lock it in place. HOWEVER, ... if you happen to turn it more than a couple of turns, ...
As I said, it only takes a few seconds to be SURE.

That's OK. It's your bike. I provided an opinion and offered what has worked for me. You got your money's worth.

.

[GSXR7ED]

I love how you’re so fair, Steve...without being demeaning to members here.

Ed

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