I keep hearing about people removing the radiator from their cmeps. I also see the v3 now comes without a radiator.
My question is how much faster is it recovering without the radiator? And how much hotter does it run at your exhaust side?
Whats the benifit of this over the water cooled radiator?
Also what are some signs that a cmep ol is due for a rebuild? I have 2 and the older one is significantly louder when running them together. But it still recovers.
The water cooled makes it use less cooling power on the outlet side, also you can at the end run warm water to empty as much as possible from the radiator. The radiator removed will get tou about 20-30% faster recovery in my experience but will need a lil more cooling on the outlet. My cmeps rin very quiet the rack they sit on vibrating makes more noise than the pumps, there really easy to rebuild and take apart and look for shavings inside the case if the bearings are going out.
Ya one is quiet and the other makes a clack sound
Could be the piston hitting the cylinder, i got a guy down by you who does a awesome job and super fast turn around. He has one of my pumps now if you want to so a rebuild or if tou wanna do it yourself the numbers on the bearings just type it into eBay and there about $20 or so.
How much does he charge? Im not sure of anything lol
500 for a full rebuild. Honestly depending on how many you have, take one apart too see bow to so it. It really is simple, theres a few tricks to getting the compressor cover off and the pistons out but it can be done in less than an hour.
Cmep-ol: pump removed from radiator 
edit: if I recall correctly the radiator is riveted in. I recall because I actually had to pull one and have a buddy silver solder a leak…
Have you ran one with the radiator bypassed? Thats is definitely a cmep removed from the radiator. Make sure to use gaution while working on it
no. I’ve run one of the later models without the radiator, and found the lack of built in cooling mildly problematic.
mind you, I was using it to “recover” my N2 push off the top of a chilled (-50C) solvent tank. It did a reasonable job, but I had to monitor temps/pressures fairly closely. guess I could have dug around for a cooling coil (MT-69).
It was convenient for that particular install that I could sit the pump on it’s ass with the inlet and outlet pointing straight up.
Im assuming the piston isnt slapping the head. Only because the pump in question gets louder throughout the run. Its not a consistent loud clack. Its one that gets louder as theres less to recover. I wonder if that pump could be starving. They are both connected to the same sieve with a T.
Can you get me in contact with your guy? Ill try to revuild it and if i screw up ill send it to him. Wheres he located?
Riverside, ill dm you his info. When i was running 4-6 cmeps i would have to have the vapor path set up right so some of the pumps weren’t starving. Check the gauges if thw one thats loud has less on the i let then ya probably what it is
I guess the easy way to figure that out is turn off the pump not in question and see if the sound changes
Ya stary to remove all variables, sending that info now
There pretty nice because it gets rid of about 75’ of piping and less restrictions but needs a lil wxtra cooling on the coil or tube n shell.
How much nore dry ice do you use without vs with
I dont use to much dey ice anyway, i use chillers for everything. But when i was just using it, the speed made it worth the extra lil bit of dry ice. Depends to on dry ice costs and if your buying totes or just by the pound.
@Cyclopath depends on the generation IIRC, I know first gen units rad is riveted in I think 2nd gens they have screws holding them to the frame. When I’ve rebuilt first gen units I drill out the rivets, drilled thru the outside of the frame and used 4 long stainless screws to make it easier to remove the radiator in the future
@Slabby Where is local to you? If near Denver I can show you how its done or rebuild them for you. In my experience when a CMEP starts getting loud its in need of bottom end bearings.
Im in california. Is it easy enough that we could do it over a video chat?
Its not hard if you have much mechanical experience
6908-2RS 6908RS
It’s not too bad but you’ll need a few tools to make it happen, as well as some red loctite and a torch. Get it taken apart and send me a PM and we can set something up.
