Industrial engine conversion. *Private* group.

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Hot Wings

Grumpy Cynic
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That chain redrive is horrific. I'd be amazed if he hasn't broken his crank.
There is enough slop in the system that the chain dancing around damps the resonance energy via aerodynamic drag. "I'm good with that"

In my case, I will use the blowby to move the oil from the crank case to the oil tank and I don't know yet if the remaining vacuum is going to be enough for the fuel pump.
I suspect we won't have enough delta to run the stock pump. The only way we will know for sure is to build/test. Even if we see enough at ground level there may not be enough at altitude. Lots of these engines ran just fine before they started putting on this style of pump so I don't think it is going to be a significant problem.
 

pictsidhe

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There is enough slop in the system that the chain dancing around damps the resonance energy via aerodynamic drag. "I'm good with that"



I suspect we won't have enough delta to run the stock pump. The only way we will know for sure is to build/test. Even if we see enough at ground level there may not be enough at altitude. Lots of these engines ran just fine before they started putting on this style of pump so I don't think it is going to be a significant problem.
There were some nasty snatching events. The guy explained that the chain adjusted itself...
I think experiment is in order for the pump. The crankcase should still have the same fluctuations. But it will be offset to positive pressure.
 

Vigilant1

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I suspect we won't have enough delta to run the stock pump. The only way we will know for sure is to build/test. Even if we see enough at ground level there may not be enough at altitude. Lots of these engines ran just fine before they started putting on this style of pump so I don't think it is going to be a significant problem.
If the carb is sufficiently lower than the fuel tank (in all regular flight attitudes), gravity flow is an attractive option. And, if going the EFI route, a different pump is required anyway.
One nice thing about an engine burning just 2.5 gal/hr is that the small required fuel tank can be put in a lot of different places. Heck, a thirty minute header tank is the size of a loaf of bread.
 
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blane.c

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Fuel pumps at the engine end only don't work well empirically anytime heat and/or altitude is added. Vapor lock. Gravity systems work fine as long as that is what they are. If you put a fuel pump at the engine and expect gravity to feed that pump 100% of the time you are asking for a problem.
 

blane.c

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If you put fuel pumps at/in the tanks in a multiple tank system you need check valves to prevent fuel being pumped overboard accidently by one tank backfilling another.
 

pictsidhe

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Fuel pumps at the engine end only don't work well empirically anytime heat and/or altitude is added. Vapor lock. Gravity systems work fine as long as that is what they are. If you put a fuel pump at the engine and expect gravity to feed that pump 100% of the time you are asking for a problem.
Who says the pump has to be at the engine?
 

Vigilant1

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If you put fuel pumps at/in the tanks in a multiple tank system you need check valves to prevent fuel being pumped overboard accidently by one tank backfilling another.
Yes, and we'd need an indication if a pump fails. If we couldn't reliably gravity flow from the main tank to the engine (most reliable option), I'd probably choose to pump fuel to the header continuously, with a return line to the vented main tank (check valves in both lines). A sensor in the header tank and an indicator on the panel tells us that the header tank is no longer full. Whether due to failure of the transfer pump or fuel exhaustion in the main tank, you've got limited flight time remaining.
 

Hot Wings

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But it will be offset to positive pressure.
Thus my use of the term 'delta' for the pressure fluctuations.

Yes, and we'd need an indication if a pump fails
That is when the noise maker quits making noise ... and shaking. :)
Design of the fuel system is really a whole different subject and will vary depending on the aircraft/engine configuration.
 

soupercooper

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PPD: piss poor design we would call that. Having the full pressure oil gallery right next to the breather with widely spaced hold-down bolts. There is not much you can do short of welding the oil gallery canal closed or drill & tap another small bolt (M4/M5) at the indicated location to apply a bit more pressure in the centre:
View attachment 103072
problem discovered is problem solved. I'm glad to find this problem now and address it now than while in the air and pumps my oil supply dry. attached is image of other side of plate, looks pretty stout to me, I think its in need of another fastener in the middle as long as I dont intrude the sealing surface to much and weaken gasket surface area.
on another note, Briggs filed bankruptcy , I'm sure there not going anywhere but that is sad news.
 

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pictsidhe

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Briggs went bankrupt and the remains have been bought up. Maybe it's an asset stripper, maybe it's someone who wants to salvage something. I am not basing future business on them continuing to build engines just yet. But the engines are still available. What I learn and develop on a Briggs can be applied to other engines.
 

WonderousMountain

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There are head replacement gaskets, bolts toqued low.
I'll cad draft a top-plate for the bad beather Housing.
It will be useful to somebody. It does look stout, but
if it's not the plate, then it's got to be fastener or gasket.
2404167s.jpgBreather cover.png
This gasket is the upgrade (exciting right.)
It looks similar, but has full perimeter lines.
Per usual I wasn't able to finish the Cover.
 
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blane.c

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Because none of the industrial engine manufacturers seem to want an aircraft connection, maybe try to use a few parts from two or more manufacturers. Then it would be easier to defend that it isn't a particular brand but an engine assembled from pieces and parts laying about the shop. I am talking about some ancillary parts.
 

Vigilant1

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Because none of the industrial engine manufacturers seem to want an aircraft connection...
Has this become an actual problem for anyone flying these engines? I know the mfgrs say they don't want/approve of this use for the engines they make, but that statement is intended to shield them from liability and probably does a good job of it.
I think the prudent thing to do for anyone flying these engines is to grind off any serial numbers. That makes it pretty hard to determine the retailer of the engine/parts, and helps protect the retailer from sanctions by the mfgr (and helps assure you can get more of them). Nothing illegal/unethical about that, IMO. After you modify the engine for airplane use, it's a different piece of hardware. Engrave your own serial number in it. Like an experimental airplane isn't registered as a "Van's RV-6" but is instead a "JoeBlow RV-6."
 

pictsidhe

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That might just work. You'd still need to buy indirectly. I strongly suspect Chinese manufacturers would be a lot more friendly. They have a whole ocean to shield them from lawyers.
 

TiPi

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I think the prudent thing to do for anyone flying these engines is to grind off any serial numbers. That makes it pretty hard to determine the
[/QUOTE]
Dead easy on the Briggs, the S/N, model no and all other info is on one of the rocker covers.

It looks like Kohler went through a few iterations to fix this problem. The alu cover and new gasket might prevent a leak without the extra bolt.
 

blane.c

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My nephew has a small engine repair shop so I asked him some questions about the 810cc. His answer follows just for general info.

Sorry have been super swamped with work but at any rate I will let you know what i can off the top of my head Yes crank shafts are forged steel very nice temper to them and if you get the tapered shaft no there Is no key way of any kind which in my opinion for a plane type installation that's gonna be a much safer route because there is no key to fail on you the center section of crank is threaded for a bolt which of course forces it onto crank shaft as you tighten it down then to pull whatever it may be off the said crank you just use all thread and couple nuts and washers to make a spanner to force it off of the shaft the newer model briggs your talking about is a great engine as far as dependability goes its very well made but there big flaw is that it has a 2 piece block to it because of it bieng made of aluminum I imagine but at any rate the thing bolts top to bottom or side to side depending on your application but they are notorious for getting themselves loosened up and well end result.as you can imagine it has an internal detination and usually leaves 4-6 small holes in the block before its done lol I have seen a few now and always tgmhe same size holes in about the same locations the solution to there design flaw is just some good ol fashioned lock tight then everything remains virtually as designed and stays together
Jeremiah Smith


Hi how are you doing
Hope that helps to answer some of your questions i do have a grenades block from 1 of those motors in my scrap pile from a generator if you would like some pictures of anything
 

karmarepair

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Has this become an actual problem for anyone flying these engines?
Apparently it was, for Engineer Spacek in the Czech republic, the SD Minisport guy. My sense is that the European distributor for Kohler got on his case for the "SE31" engine based on "Brand K". Maybe TiPi knows more about that. Or I can strobe Engineer Spacek (Ivan?) for the story.
 
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pictsidhe

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My nephew has a small engine repair shop so I asked him some questions about the 810cc. His answer follows just for general info.

Sorry have been super swamped with work but at any rate I will let you know what i can off the top of my head Yes crank shafts are forged steel very nice temper to them and if you get the tapered shaft no there Is no key way of any kind which in my opinion for a plane type installation that's gonna be a much safer route because there is no key to fail on you the center section of crank is threaded for a bolt which of course forces it onto crank shaft as you tighten it down then to pull whatever it may be off the said crank you just use all thread and couple nuts and washers to make a spanner to force it off of the shaft the newer model briggs your talking about is a great engine as far as dependability goes its very well made but there big flaw is that it has a 2 piece block to it because of it bieng made of aluminum I imagine but at any rate the thing bolts top to bottom or side to side depending on your application but they are notorious for getting themselves loosened up and well end result.as you can imagine it has an internal detination and usually leaves 4-6 small holes in the block before its done lol I have seen a few now and always tgmhe same size holes in about the same locations the solution to there design flaw is just some good ol fashioned lock tight then everything remains virtually as designed and stays together
Jeremiah Smith


Hi how are you doing
Hope that helps to answer some of your questions i do have a grenades block from 1 of those motors in my scrap pile from a generator if you would like some pictures of anything
Id be interested in usable taper cranks.
 

pictsidhe

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Re Briggs bankruptcy.
They have been bought by KPS, a private equity group. Unlike many such groups, they are not vultures asset strippers. They like to fix bankrupt companies, then sell them as going and viable businesses. So, looks like Briggs will survive this. Although without its blood sucking greedy board of directors.
 
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