Carrera tensioners problem

[jim fling]

I posted a week ago about noisy chains after a complete rebuild and installing the oil fed tensioners in my 77 engine. I have pulled them and they do not have air in them and they seem to be OK.
I read on one of the posts that the chamber alongside the piston is a pressure accumulator. The post stated that the nipple or port on the top was the pressure relief for the accumulator and that it was supposed to relieve pressure at 14 PSI.
I made a test setup ( see photo) to test the relief pressure thinking that if they relieved at a lower pressure this could be the answer to my problem and others who say they had 2 or 3 bad ones in a row.
First, my experiment shows that the tensioners will purge air through the relief valve and also through the piston as it is just a close fit with no O ring and air can get out from around the piston. Since it is a close fit it is probable still a good idea to bench plead the piston.
Second, One of my tensioners (R) one relieved pressure at 10PSI the left one relieved pressure at 6 PSI.
Does any one know what the relief pressure should be and if there is a rebuild kit for the pressure relief spring?

[boyt911sc]

Jim,

I have no answer to your questions but I'm interested to know more about your hydraulic pump delivery system. Thanks.

Tony

[skidmark]

I have had multiple new bad ones. To the point where I test run them with the chain covers off. At the top of the piston is a small rectangular opening that should bleed oil out of it to purge the air out. It gets clogged with debris on assembly and wont bleed the air from inside the piston. I have seperated the top of the piston and cleaned the passage to fix it. It is a press fit and does not come out easily. I will try to post a pic.
Mark Kinninger

[Kraqus]

Who is the Manufacturer?

Originally Posted by boyt911sc

Jim,

I have no answer to your questions but I'm interested to know more about your hydraulic pump delivery system. Thanks.

Tony

Ha ha ha! Exactly what I was thinking.




Benny

[jim fling]

My system is just a oil reservoir in my case it is a 2 oz. cartridge like a large syringe. I pressurize that with compressed air at about 20 PSI. The output of the reservoir is connected to the input of a low pressure regulator with a gauge output and to the oil line connection to the tensioner. This allows very small accurate pressure adjustments to be delivered and monitored on the gauge.
By the way, I calculated the amount of hydraulic pressure that 10 PSI would exert on the tensioner piston. It is only 4.4 pounds. The spring exerts way more pressure than that.

[jim fling]

I forgot, These were from pelican along with the kit and new style chain wheel supports.
I have seen the oil come out of the slots on the top of the piston but only when the compressing a "pumped up" piston and pushing it down with a clamp.