R109 Adjustable question for "usual suspects"

[LeadTurn_SD]

I am now the proud parent of a Scubapro R109 Adjustable (unbalanced) that I got from ebay. Overall the reg is in great shape (apparently very lightly used), the exhaust "T" and rubber purge cover (old style with round holes) are in very good shape, and the diaphragm and exhaust valve appear to have been upgraded to silicone at some point; the orifice is chromed brass.

But it does need a rebuild (slight, constant freeflow that can't be stopped with adjuster; on inspection soft seat is deeply grooved)... and it looks like it has an older version of the poppet with the bonded soft seat I think:

This is my first scubapro rebuild, so I have a question (and others may follow ):

Can the poppet pictured above be replaced with the "Duro" poppet... and if so, will the original lever and spring still work correctly?

I'm hoping to keep this unbalanced so that I can simply change the 2 o-rings and puck-style soft seat whenever I need to service it.....

Thanks!

Best wishes.

 

[redacted]

The poppets are a direct swap. The lever could be a problem as a minority of the older levers may not operate well. I had about 1 in 10 that had to be replaced. A number of other threads have talked about the problem.

 

[LeadTurn_SD]

Thanks awap!

 

[Luis H]

Yes.

That is not even the earliest poppet. I think that one came out in the mid 70's or late 70's.

I have several NOS poppet's like that one.

My guess is that you have the second generation of lever, which seems to work fine with the latest poppet.

You probably also have the second generation spring. You can tell if it is the second generation since the center coils are further apart then the coils toward the two ends.

 

[LeadTurn_SD]

Yes.

That is not even the earliest poppet. I think that one came out in the mid 70's or late 70's.

I have several NOS poppet's like that one.

My guess is that you have the second generation of lever, which seems to work fine with the latest poppet.

You probably also have the second generation spring. You can tell if it is the second generation since the center coils are further apart then the coils toward the two ends.

Thanks Luis!

From your description, it does sound like I have the 2nd generation spring; and I believe the lever on my -109 is the same as the one pictured in the center of the picture couv posted in the -109 lever height thread in the DIY section:



I'll see if I can chase down a "Duro" poppet locally.... only one scubapro shop in town, and I have a gut "feeling" I'm gonna strike out.... otherwise, the "search" for a poppet may be on!

Best wishes.

 

[BlueWaterDiving]

Make it a balanced. All you have to do is change the poppet and the spring and put a balance chamber in it. If you need help let me know.

 

[aquaregia]

I had two with that poppet. One had a 30deg lever and one had a 45deg lever, so I'm 1 in 2

 

[Packhorse]

As Red said turn it into a BA, its pretty simple.
But if you want to keep it as is I have a "duro" poppet spare if you cant find one local.

 

[halocline]

Now I can see from the photo of the three levers that most of mine are the middle one, not the one on the right. I've never had a problem with either the G250 poppet or the G200 (duro) poppet.

There are advantages to converting it to balanced, as there are leaving it unbalanced. The nice thing about the unbalanced duro poppet, is (as you said) rebuilds consist of 2 o-rings and a new seat every other time. If you convert it, you'll need to buy a rivet seat (probably $4 or so) and find those tiny o-rings for the balance chamber. There's a thread for that, too, that you might remember.

Depending on your first stage, it will breathe really similarly balanced or unbalanced. Personally, I've found my balanced ones are a little smoother, but others say they can't tell a difference and I believe them.

 

[AquaNSun]

Hope you don't mind I add another question. For R109 (unbalanced), is there a rebuild manual available online to download? Particularly tips and advice on adjusting cracking pressure and proper lever height. I'm also looking for a cross-sectional diagram similar to the one below if available particularly where the lever engages the poppet stem detail.

Thank you.