The Rope Trick - Stuck Valves

How to keep the Cessna 170 flying and airworthy.

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N1478D
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Post by N1478D »

Rudy Mantel wrote:Joe, how much MMO do you add to your oil and fuel ?
Rudy
Rudy, I quit adding MMO to the oil after a George post on the old site. To the gas I add a minimum of what the MMO directions state, and usually it is more than that. I can't remember here at the house how many ounces of MMO per 10 gallons of gas the container states, but I usually had half of a small container to each side regardless of how much fuel I am putting in.
Joe
51 C170A
Grand Prairie, TX
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wa4jr
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Post by wa4jr »

I use the recommended ratio of 4 ounces MMO to 10 gallons of fuel. I premix the MMO in with the fuel at the gas station in my 55 gallon drum that I use to cart the mogas to the plane in. I saw somewhere in a previous post about adding MMO to the oil just prior to the oil change...sort of like an engine flush. Run the engine for five minutes and then drain. In theory it sounds like a good thing to do....but I am afraid it would mess up the oil analysis if a lot of goop got loosened up and came out of the engine...but then again I'd like to have the goop out if there is any in there :?
John, 2734C in Summit Point, WV
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N1478D
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Post by N1478D »

I like to put the MMO in before I pump the gas so that it is mixed up good. So, if 4 oz per 10 gallons is good, 5 or 6 oz must REALLY be good. :lol: Not knowing exactly how much fuel it will take to fill the tanks, and believing that using MMO is not an exact science, the theory is that some extra isn't going to hurt. But, if I had an empty container like John, I would use the ratio of 4 ozs per 10 gallons of fuel also.

For What It's Worth: If my plane had never had a stuck valve, I would not start using MMO just because other people recommend it. And, once I reach the new cylinders point I will try running without MMO.
Joe
51 C170A
Grand Prairie, TX
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GAHorn
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Post by GAHorn »

To help you "stir up" the MMO, ....why don't you just save a little money and make your own MMO? You can get kerosene from the sumps of the airport jet-truck, red food dye from the grocery, and perfume from the cosmetics counter at WalMart? (Although I'm not sure what the carrier of the red food dye is. If it's alcohol or water that would be bad. But maybe, like the MMO and kerosene, it would be diluted enough that the FAA and insurance adjuster couldn't detect it. Maybe just do away with the perfume and use up the old extra Hyd 5606 from the back of the hangar.) 8)
(standing by for incoming, and the sheet-music for hokey-pokey)
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N1478D
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Post by N1478D »

gahorn wrote:To help you "stir up" the MMO, ....why don't you just save a little money and make your own MMO? You can get kerosene from the sumps of the airport jet-truck, red food dye from the grocery, and perfume from the cosmetics counter at WalMart? (Although I'm not sure what the carrier of the red food dye is. If it's alcohol or water that would be bad. But maybe, like the MMO and kerosene, it would be diluted enough that the FAA and insurance adjuster couldn't detect it. Maybe just do away with the perfume and use up the old extra Hyd 5606 from the back of the hangar.) 8)
(standing by for incoming, and the sheet-music for hokey-pokey)
George, I just knew you would not be able to resist responding. :lol: Understand that you will start using MMO once it comes out in the "new and improved" version in green bottles.

By the way, where's the nice photos of a good baffle seal installation with parts list of materials used :?: :cry: There has to be more than one of us that needs that information.

And what do you think of the CO testing and education at 170 fly-ins?
Joe
51 C170A
Grand Prairie, TX
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GAHorn
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Post by GAHorn »

Well, for you guys with the engine cooling air boxes (all aircraft prior to the '53 B-models) you might look at a product handled by AVIALL 800/284-2551 called:
Cowl vent seal. 5/16" X 1-7/16", Neoprene impregnated heavy cloth sewn around a felt core. (The cross-section looks like a large sperm.) Installed with rivets or staples, and used around carb air intakes adn cowlings. PN VS6491 - Cowl Vent Seal.
I don't know why a guy couldn't make his own with 3" X 9' common silicone baffle seal material sold by aircraft spruce. You could just roll it back upon itself and wire/rivet it back onto the baffling, just like the illustrated Parts Catalog shows. Sorry, I don't have any photos of it.

As for the CO testing, I think it might be interesting, but several of the magazines have already done it. The important thing is to buy a CO detector that will work at very low levels. (US made units don't because the fire codes here are geared toward false alarm prevention, but if you wait until 50 PPM CO levels are detected in the cockpit, it's too late.) The AIM units sold by Sporty's get high marks. (You might actually have a major CO leak in your airplane, Joe. It affects your perception of speed.) :lol:
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N1478D
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Post by N1478D »

gahorn wrote:
Cowl vent seal. 5/16" X 1-7/16", Neoprene impregnated heavy cloth sewn around a felt core. (The cross-section looks like a large sperm.)

As for the CO testing, I think it might be interesting, but several of the magazines have already done it. The important thing is to buy a CO detector that will work at very low levels. (US made units don't because the fire codes here are geared toward false alarm prevention, but if you wait until 50 PPM CO levels are detected in the cockpit, it's too late.) The AIM units sold by Sporty's get high marks. (You might actually have a major CO leak in your airplane, Joe. It affects your perception of speed.) :lol:
WOW, did not realize that several of the magazines had been to our 170 fly-ins and individually tested our 170's. Missed that :!: It's kind of amazing that after having several of the magazines educate us 170 drivers that so many of us still have any questions. :P

Thanks for the part numbers and suggestions on possible baffle seal solutions George. That does not mean I will throttle back to keep from passing you by in our contest though. :wink: I will do you one favor though, I will not ask you how come you know what a large sperm looks like 8O And, if that means that your close relationship with flyguy has resulted in some experimentation, to quote Jerry Seinfeld, "and there's nothing wrong with that". :lol:
Joe
51 C170A
Grand Prairie, TX
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GAHorn
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Post by GAHorn »

Well, Joe! I didn't realize what you were really wanting was someone to test your airplane for free! I thought you were just curious about Cessna 170/172's in general and how they fare with regard to CO. (Typically they get CO entering the cockpit from faulty exhaust systems, gearleg/fuselage, strut/fuselage seals, and from leaking door seals and back-flow from the tail cone. Sometimes a leaking firwall will come into play. Finally, the cabin-heat valve is sometimes a culprit. I'll never understand why Cessna thought it was OK to let that valve open up directly to the engine compartment with all those leaky exhaust-riser clamps. I've sealed my clamps with stainless steel foil.)
But if you like, I'll buy a detector and we can take a ride in your flat-wing airplane and see how it does. :wink:
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N1478D
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Post by N1478D »

gahorn wrote:Well, Joe! I didn't realize what you were really wanting was someone to test your airplane for free! I thought you were just curious about Cessna 170/172's in general and how they fare with regard to CO. (Typically they get CO entering the cockpit from faulty exhaust systems, gearleg/fuselage, strut/fuselage seals, and from leaking door seals and back-flow from the tail cone. Sometimes a leaking firwall will come into play. Finally, the cabin-heat valve is sometimes a culprit. I'll never understand why Cessna thought it was OK to let that valve open up directly to the engine compartment with all those leaky exhaust-riser clamps. I've sealed my clamps with stainless steel foil.)
But if you like, I'll buy a detector and we can take a ride in your flat-wing airplane and see how it does. :wink:
Free is good, but, what really is free :?: I was thinking more of a group purchase and sharing the equipment/knowledge. I do have a BFR coming up, that would give you a chance to ride in a classic straight wing aircraft.
Joe
51 C170A
Grand Prairie, TX
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