[Dabbles]

Seems like your still going to lose the grease, whether the gas is vented out of the crank case, or allowed back into your loop. It's also kinda B.S. this pump originally had a non-food-grade grease to begin with, and now PTFE? Teflon is carcinogenic. I realize PTFE is a common material found in extraction systems, but Damn there has to be better martial out there to use. Wish I would have not bought this pump. I wouldn't have if I'd known about all of these issues.

[learningta]

Originally Posted by Dabbles

Seems like your still going to lose the grease, whether the gas is vented out of the crank case, or allowed back into your loop.

Bearings are a wear item, just a question of how long they take to wear out given your application, I just think its a bit ridiculous that none of the retailers that are selling these pumps and rebuild kits for them are listing bearings on their website as well.

It's also kinda B.S. this pump originally had a non-food-grade grease to begin with, and now PTFE? Teflon is carcinogenic. I realize PTFE is a common material found in extraction systems, but Damn there has to be better martial out there to use.

I agree that the non-food grade grease is bad news, teflon is carcinogenic but chances are a lot of people are exposed to way more teflon due to cookware than they will be from an extractor. If the crank case is vented hopefully nearly all the grease that is lost from the bearings goes out the vent line and not into your product or butane tank.

Wish I would have not bought this pump. I wouldn't have if I'd known about all of these issues.

Ditto, I'd advised a Haskell but cost of the Haskell and a big enough compressor to run it to capacity was prohibitive at the time. That may change given the headaches with this pump.

[learningta]

Originally Posted by Rickys bong

A couple of points: Ceramic bearings won't solve the problem since they need lube too. Shielded bearings generally don't have seals. Shields are non contact dust shields meant to keep dust out of the bearings and lube in.

There are two types of seals, RZ and RS. RZ are light contact which means they bare touch for minimal rotating friction. they will also allow gas to get past. Type 2RS have contact seals on both sides and will be the best off the shelf solution. There are others, but none are designed to seal gases from the bearing grease.

I should've taken pictures but when I pulled the cover off this pump both outside bearing seals were loose and bouncing around on the crankshaft. At which point, even without the influence of the solvent gas, any grease still remaining is going to be flung out into the crankcase by centripetal force. What happens after is irrelevant, because at that point its no longer lubricating the bearings.

Now, chicken-or-the-egg question would be did the seals on the original bearings pop loose because the bearings were going bad, or did the bearings go bad because the seals popped loose from boiling grease (either due to vacuum pulled on the grease or solvent entrapment)?

For those trying to picture the above here's a good visual with some more options: https://www.astbearings.com/bearing-closures.html

I'm away from the shop and dismantled pump right now but makes me curious if its possible to get those crank bearings with type TTS seals, and also what the max temp those bearings get to when in operation.

Your best bet is still venting the crankcase and even better putting a fitting in the vent hole and plumbing it outside. That way there's little chance of gas leakage indoors.

Thats my plan

Put a flowmeter (rotameter) on it rather than a valve. That way you can monitor blowby flow.

Any suggestions for one?

Even if you bought Vastly improved bearings any leakage from them is hidden and you won't know they are leaking grease until they get noisy. Grease that leaks from them likely will get into your butane stream and you won't know it.

RB

Absolutely. Part of me is thinking about ditching the cooling fan in this pump (IMHO I'd rather see more power devoted to pumping and power an external explosion proof fan to cool the heat exchanger and cylinders), at that point wouldn't take much to weld a fitting for an airtight sight glass so you can see whats happening with your pumps bottom end. Would answer some questions anyways.

[Dabbles]

Have you received the new bearings from bho's yet? I ordered a pair too. We'll see!

[learningta]

Originally Posted by Dabbles

Have you received the new bearings from bho's yet? I ordered a pair too. We'll see!

Tracking shows it as there but my day job shipped me out of state and haven't gotten the chance to open it yet

[learningta]

Originally Posted by Dabbles

Have you received the new bearings from bho's yet? I ordered a pair too. We'll see!

You order from Bhogart? Those shitheads won't have anything to ship you for least 2 weeks. I got home expecting to have a package from them on my doorstep, no package called for tracking and was told nothings shipped because nothing has arrived from the OEM. Would have been real useful information the day I placed my order over a week and a half ago now.

[learningta]

Originally Posted by learningta

Tracking shows it as there but my day job shipped me out of state and haven't gotten the chance to open it yet

This is probably confusing and it doesn't look like I can edit it...got my packages confused, this tracking was for a shipment from Ecogreen with my pump rebuild parts, which was shipped the next day and arrived shortly thereafter. Bhogart sent me an order acknowledge but never followed that up with a tracking no for my bearings, because they hadn't shipped because they're still on a boat from China or something.

[CMEP Shop]

Been reading a few of the threads here.
First: Full Ceramic bearing do not require lubricant. They are perfect for using in these pumps. You will never get grease contamination of your gas if you use full ceramics. I sell NSK full Ceramics for 110 each. contact me.

2nd: do not vent the crank case because you will no longer have an explosion proof pump. Instead make sure to monitor the temperature of your pump. When you notice recovery times go down, turn off pump and let cool for 2 hours. Have a second pump ready and that is cold. You are getting blow-by and that is how the case get full of gas.

3rd, make sure your pump is above the top of your recovery tank and coil. this will make sure you are only pumping gas and no liquid.

4th, I recommend never heating gas to higher than 110 degrees. Even if you are making clear. This is extremely dangerous and will increase the amount of work that will have to be performed to keep it working properly. IE: higher temp crash the pump sooner.

++++++++++++edited to remove terms of use violation+++++++++++++

[killa12345]

Originally Posted by CMEP Shop

Been reading a few of the threads here.
First: Full Ceramic bearing do not require lubricant. They are perfect for using in these pumps. You will never get grease contamination of your gas if you use full ceramics. I sell NSK full Ceramics for 110 each. contact me.

2nd: do not vent the crank case because you will no longer have an explosion proof pump. Instead make sure to monitor the temperature of your pump. When you notice recovery times go down, turn off pump and let cool for 2 hours. Have a second pump ready and that is cold. You are getting blow-by and that is how the case get full of gas.

3rd, make sure your pump is above the top of your recovery tank and coil. this will make sure you are only pumping gas and no liquid.

4th, I recommend never heating gas to higher than 110 degrees. Even if you are making clear. This is extremely dangerous and will increase the amount of work that will have to be performed to keep it working properly. IE: higher temp crash the pump sooner.

If you have any questions, or parts needs please contact me at Rob@CmepShop.com

website should be up and running over the next few weeks as parts arrive.

HAHA...$110 for each ceramic bearing....i figured a bike shop would get in on this. Advertise the right way with the forum. Still cant get over $110 each bearing.

Only a roadie would say something like this....LOL

[learningta]

CMEP shop, mind giving us specs and pictures on these bearings? For double or more what anyone else is getting for them I have high expectations.

Do you have an online storefront or offer any other products for the CMEP pumps?

How and where exactly do you expect us to monitor the temp of the pump? Explain to me if I'm wrong, but more blowby means less gas compression (thus the slow recovery times), and that would mean less temperature delta between inlet and outlet lines, not more. The parts which would get hot from spewing out their grease would be internal to the crankcase and I don't know how anyone is going to attach a thermal probe to crankshaft rotating at 1800 RPM.