Author Topic: Hoglet, an European Version  (Read 15863 times)

Offline Dave Otto

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Re: Hoglet, an European Version
« Reply #30 on: October 30, 2017, 12:10:02 AM »
Nice Work Achim!

Dave

Offline gbritnell

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Re: Hoglet, an European Version
« Reply #31 on: October 30, 2017, 12:06:27 PM »
Hi Achim,
I've been following along with your Hoglet build.
Here's something I found when building my V-twin engine that might influence the remaining design of your engine. I built my engine as a 90 degree V-twin basically for the fact that it would be smoother running than a 45 degree engine, which I can't say made much of a difference. When I first got it built and running I would start it up and after a couple of minutes it would start to hesitate or run erratically. I would adjust the fuel mixture needle a little richer and the engine would smooth out. At this point after another 30 seconds the engine would start doing the same thing and by richening the needle would again smooth out. Finally the engine would stall and it wouldn't restart. After letting it sit for some time the engine would start up and run rich so I would adjust the needle back towards lean and everything was good but after a few minutes the same symptoms would appear.
I was running the engine for a friend and he remarked that when the engine started to hesitate that the fuel in the clear fuel line could be seen pulsating away from the carb.
What was happening was the manifold and carb were getting hot from the heat in the heads and causing a vapor lock condition. By opening the needle it was momentarily allowing more fuel to flow until more heat was generated.
To remedy the condition I pulled the manifold off and machined .03 from each end. I then made a Corian spacer to insulate the manifold from the head. My heads and intake are both made from aluminum.
I have seen quite a few Hoglet videos and the engines seem to run well but I don't know for what period of time. Being as they are 45 degree engines the path to the carb is even shorter than my engine so I would think that they would be prone to the same heat conditions as mine. 
I'm telling you this so that maybe you could make some kind of provision to insulate the manifold from the heads before you get to that point in the build.
gbritnell
Talent unshared is talent wasted.

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #32 on: October 30, 2017, 07:11:24 PM »
Hi George, thank you very much for taking the time to report about your experience with this type of model engine.
I appreciate it very much, that all this knowledge is available in this forum and guys like you share it with all of us.
Today I have started to make the valves. If that is finished, next job will be the painting of the cylinder heads followed by making the intake manifold.
At my metric adapted design it would be difficult to add some Corian spacers but there should be a possibility to insulate the carb by a Corian adapter.
I will see what could be done, it is good to know that there is a point to watch. 
 
Kind Regards
Achim

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #33 on: October 30, 2017, 07:12:42 PM »
Nice Work Achim!

Dave


Hi Dave, thanks for watching.
Kind Regards
Achim

Offline Florian Eberhard

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Re: Hoglet, an European Version
« Reply #34 on: October 30, 2017, 07:32:08 PM »
Hi Achim

I think you could also use some fabric-base laminate (=Hartgewebe)  since this is available as round stock (or tubes!) to insulate your carburetor and I guess this is a bit stronger than corian.

Florian

Offline Dave Otto

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Re: Hoglet, an European Version
« Reply #35 on: October 30, 2017, 07:36:16 PM »
Hi Achim

I think you could also use some fabric-base laminate (=Hartgewebe)  since this is available as round stock (or tubes!) to insulate your carburetor and I guess this is a bit stronger than corian.

Florian

It would look pretty cool too!

Dave

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #36 on: October 30, 2017, 08:24:28 PM »
Hi Achim

I think you could also use some fabric-base laminate (=Hartgewebe)  since this is available as round stock (or tubes!) to insulate your carburetor and I guess this is a bit stronger than corian.

Florian
Hi Florian, also a good idea and easy to get.
Kind Regards
Achim

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #37 on: November 01, 2017, 07:13:06 PM »
A bit more progress was made, because of some extra bank holidays in the south of Germany.
Valves are made and also the valve seat machining in the heads is finished.
Valve seats are also made now and the usual valve grinding operation with final vacuum test.
Some paint and a hopefully final assembly of the cylinder heads.

Kind Regards
Achim

Online sco

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Re: Hoglet, an European Version
« Reply #38 on: November 01, 2017, 07:27:04 PM »
Looks super crisp Achim!

Hope it runs as good as it looks,

Simon.
Ars longa, vita brevis.

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #39 on: November 19, 2017, 11:45:51 AM »
Hi Simon, thanks for the friendly words. Compression is not bad and the engine is bouncing, so hopefully we are at the right way.


In the meantime  I have made the inlet manifold with the carburator adapter, made from Phenol fabric-base laminate.
Thanks again to George Britnell and Florian with the advice to watch the thermal isolation.
And here we are today.
Kind Regards
Achim

Offline Roger B

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Re: Hoglet, an European Version
« Reply #40 on: November 19, 2017, 02:24:45 PM »
Excellent  :praise2: The advice regarding carburettor temperature/insulation is good. I was only able to get my vertical engine running properly once I made a Delrin adaptor to keep the temperature down.
Best regards

Roger

Online Kim

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Re: Hoglet, an European Version
« Reply #41 on: November 19, 2017, 03:45:15 PM »
That looks really sharp, Achim!  Just beautiful!
Kim

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #42 on: November 19, 2017, 04:18:36 PM »
Thanks, Roger and Kim..
Kind Regards
Achim

Offline Dave Otto

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Re: Hoglet, an European Version
« Reply #43 on: November 19, 2017, 05:13:31 PM »
Very nice!

Dave

Offline fumopuc

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Re: Hoglet, an European Version
« Reply #44 on: December 06, 2017, 07:26:13 PM »
Thanks Dave, good to know you are still watching.


We are close now.
Ignition, fuel cell and two proper exhaust pipes are missing.
A first fire up could be tried with a temporary fuel cell and this shown exhaust.
« Last Edit: December 06, 2017, 07:53:55 PM by fumopuc »
Kind Regards
Achim

 

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