T80 Compressor help needed. How to remove the exhaust plate from the head.

NeoTokyo

NeoTokyo

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Aug 27, 2012
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Hello everyone!

I need some T80 advice from the experts out there.

I have an older generation T80 with the pressure relief valve on top.
I need to know how to remove the exhaust plate from the head.
I have removed the 4 screws but its not budging!

The reason why I need to remove this is because I need to clean out the exhaust area fully.
Mason bee's crawled in through the air port and filled the entire thing up with eggs and leaves.
This happened under the care of the last owner as I knew that it didn't produce much air at all when I bought it and would have to rebuild it.
Well I guess the last owner though the same thing because the diaphragm and reeds are all new.

I spent about half an hour shaking and poking all the debris out but there is still a lot crammed in there.

Here is a picture, also you can see that the 4 screws are removed.

Thanks for you help.

IMG_8952.JPG
 

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I just use a plastic pry tool or small screw driver, if the screws are out,
it's just stuck maybe someone used gasket sealer.
I always wipe everything down with rubbing alcohol
never scuff or sand the valve seats just wipe the seat and the reed.
 

Thank you Winner, that answers a major question on if its just stuck or screws off.

Now this is REALLY stuck, how would you recommend un-sticking it?
Should I use heat? Should I soak it in PB Blaster?

I cant get anything on the sides to pry it out. :(


A friend of mine gave me his T80 for parts but his head is in poor shape and needs de-oxidized and a new reed.
 

I DID IT!

Ok so I just took my torch to it and warmed it slowly, then I took my rubber mallet and heat around the outsides.

Then it just popped off. :D

Thanks again for letting me know that it wasn't threaded in.
 

So with this in mind, I will be storing my compressors differently from now on. :D

What was left inside.

IMG_8955.JPG

IMG_8957.JPG
 

I cap all openings (after I sanatize them)to my dredge pumps / air compressors to prevent anything crawling inside of them when they are stored. and all the caps have nylon wires attached to them so I don't lose them.
 

Yeah, I am pretty sure that nest was years in the making.
It is a Gold King dredge to give you an idea of age and it has hardly been used. :D

Russ that is great advice, I will be getting those parts tomorrow.

I am also capping off the pop off ontop and running another one on the fitting.
Should I also run my pressure gauge at the fitting?

How many psi do you guys run while working aggressively to keep up with your oxygen demands?
 

Size of person, weight, physical condition, depth your diving predicates your needed pressure. The size of the reserve tank is a big factor also. All regulators are adjustable and adjust to your own personal comfort level. Same with popoff valve, adjust the 2 and your golden. John
 

I wouldn't cap off the popoff on top, that top area can build a lot a pressure if the exit is blocked.
pressure = heat
 

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The caps are ONLY for non-running or storage of the equipment. BUT not placing one on the pop-off valve might be a smart thing! its not open to the atmosphere anyway! mine isn't covered.
 

On a T80? Down to maybe 35psi at the minimum, usually at least 40 or more. But what really makes it is the RPM of the motor. Be sure to set the pulleys to get the needed rpm from the T80. So if you run 3/4 throttle that would be 3600 x .75= 2700rpm and you want 1800 max for the T80. If you have a 2½" pulley on the motor then you would need a 4½" pulley in order to get enough rpm to breathe. If you have the 6" pulley that came with some of them, it will not give you enough air more or less just based on the age of the unit. It sucks to have to hold your breath to let the compressor catch up but we've all done it... 2 to 1 is a good starting point which would be 2½" to 5" for the compressor at 3600rpm. Personally I would pick up an rpm gauge and do the math to match it if you can't breath.

https://keeneeng.com/pamphlets/introHooka.html
 

On the pop off valve I was going to run one off the side of the head, but I suppose I could double up and run the top at a higher PSI for a backup and run the one off the side for normal adjustment.
I read not to have the pressure too high otherwise it would create too much heat and wear out the diaphragm quicker.

On both of my T80's I have the 6" pulley and the motor pulley seems smaller than 2.5".
I cant get to it easily to measure with the pump in the way so I am just guessing.

What engine RPM should I run to be at 1800rpm on the T80?
Was your calculation made based on a 6" and 2.5" pulley?


As for working condition, I am a large fellow and I am raking and throwing rocks like crazy underwater so I will be using a lot of air.
As it is I already hold my breath while working hard, usually about 10-15 seconds while working really hard and upwards of 30 seconds while cleaning gold off the bedrock.
I have gotten pretty use to holding my breath while working over the last few years.
It will be a great pleasure to be able to hit those deeper holes with this thing, as for the shallows I will still use a mask and snorkel.

Now my regulator is an old OLD OLD Scuba Star regulator.
I have no idea if it is still set for Scuba or has been modified for Hooka, it did come with my Hooka though.
Does anyone know how to modify these if it is not set for hooka?
I am running thin on cash and cant get a new regulator until I have a good payday.

My reserve tank is about 5 gallons, its an old steel compressor air tank and will work for now until I buy a $75 dollar Keene tank.

I have not bought an inline filter but and was wondering about Harbor Freight, they are 40 micron.
The 3/8" is rated for 80 SCFM @ 100 PSI
But there is a Cancer warning on them..... What do you guys think about these?
Does Lowes or Home Depot have a filter that would be better that we can use?

I don't have a chest harness yet, does anyone have any write ups on how to make one?
 

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for my reserve air tank I use a stainless steel syrup tank and welded new fittings on it for my air lines. if you could get one of these , try to get their quick disconnect fittings that are used on it.plus remove the air line that goes into the tank (TO RESTRICTIVE !!) I wont use any steel tanks because of the rust involved. and a air/water filter is a smart move on your part. I like my S.S. tanks because I can open them up and PROPERLY clean / sanitize them to prevent any mold from growing! plus they were free to me!
 

Where would you get a SS Syrup tank? I have heard people say that before but I have not been able to find one at all.
 

Well .. You probably didnt search hard enough . If you go on ebay they a couple i found them simply by typing "syrup stainless steel tanks".

They are exactly like the ones on the dahlke dredges.
 

I was looking locally, I don't do much with eBay anymore but thanks for the suggestion.
 

I got mine from a guy in Ohio that worked for a big soda company. they had thousands of them stacked up to get rid of them. he got me two ,had them cleaned and shipped to me for free ! you just cant beat that! I fixed one up for my 4 inch dredge and have the other for a spare. he sent extra lids and gaskets with it.
 

Neo go to shorts metals recycling, fig tree swap meet or the jolly jerk has had them in the past.Hit craigslist as seen there also -John
 

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