First Start - C59A

Ziggster said:
Thanks again! That will be my chassis! Dash and rad are just mocked but very close to where they’ll end up. It is supposed to look something like this when done (I hope). lol!
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This looks interesting but needs front brakes.

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Maybe, maybe not. Still not sure what direction I’ll go with brakes, but probably yes due to the weight of the flathead out front. Richard Scaldwell, the builder of the real GN JAP on which the 3D model is based on, and his daughter, race without any front brakes, as well as many other cycle car builders/drivers.

https://youtu.be/H3CSZF7Hekw?si=iU5dXULnapsu8Pfg
 
Got it running again a few days ago. Removed the thermostats and got most if the air out of the coolant system. This time rad core got hot as last time the core was cool to the touch after running 5 mins. It had run out of fuel after 6 mins of running this time, and 5 mins of previous run time. So, she went through a gal of fuel in about 11 mins of run time at around 2,200 rpm.
She still got too hot with temp gauge hitting 212F, so shut her down. Temp switch for fan is set to 180F, it did finally come on just after I shut the engine down. So, either temp gauge is off, or temp switch. I let her cool down a bit, and ran her for another 6 mins, but again had to shut her down due to high coolant temp.
The smoke coming out of the exhaust collectors has now disappeared. I’m in the process of drawing/fabbing up a rad shroud, and will have the fan running for the next start-up. This will be the last start-up to break-in the cam.

Some links to vids of this round.

https://youtube.com/shorts/upzCS6N6CQo?si=gEjZPnORzMCBwIB4

https://youtube.com/shorts/fY2J3zZvgtM?si=4zeF99CPwkErxc-E

https://youtube.com/shorts/JnSXUbfLPKo?si=eLku59Q0B3UqBjLm
 
Very cool. Congrats. What a great feeling.

Regarding the hot temps. It's hard to tell from the video, but is it set up so both the head outlets and the water pump outlets collect/merge to one, enter the rad and return? Again, hard to see, but is the return at the bottom of the rad or on the side?
 
Yes, if I understand you question correctly. The two coolant outlets are teed together just over the bell housing, and that pipe runs to the rad inlet at top of radiator. Same goes for the two pump inlets. They are teed together just under the crank pulley and that pipe runs under the engine towards the rear. It goes up near the rad (follows same path as inlet pipe basically), then turns 90 degrees just in front of rad, and then runs down on an angle towards the rad out at the bottom of the rad.
Checked coolant level last night, and added about a quart, so that has me a little worried. Checked oil, and oil looks fine, so hopefully, coolant was still low a quart.
 
Ziggster said:
Yes, if I understand you question correctly. The two coolant outlets are teed together just over the bell housing, and that pipe runs to the rad inlet at top of radiator. Same goes for the two pump inlets. They are teed together just under the crank pulley and that pipe runs under the engine towards the rear. It goes up near the rad (follows same path as inlet pipe basically), then turns 90 degrees just in front of rad, and then runs down on an angle towards the rad out at the bottom of the rad.
Checked coolant level last night, and added about a quart, so that has me a little worried. Checked oil, and oil looks fine, so hopefully, coolant was still low a quart.
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Let us know what you find. If you have a digital thermometer, I'm curious on the temp readings of the piping leading to the rad and returning back to the motor.
 
Tim Ayers said:
Let us know what you find. If you have a digital thermometer, I'm curious on the temp readings of the piping leading to the rad and returning back to the motor.
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During the first run, I did bring out my multi-meter with a thermocouple and a measured the coolant outlet pipe just after the rubber elbow on the DS head. This was maybe 5 mins after shutting the engine down. Coolant pipe temp was 180F. I then decided to measure the actual head temp on the DS. It was 200F. I’ll likely invest in an infrared thermometer soon.
 
Tim Ayers said:
True & good point. I'm more curious if the coolant is flowing properly the way it's set up.
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Yeah, this is the question. I watched a YT vid after my startup, where they dynoed a flathead. Of course, they (Ed Smith actually made the pipes himself!) also had to tee the coolant connections. The tee for the outlet coolant connections had two nicely sweeping sections of pipe, whereas the tee at the pump inlets was more like an “h”shape (sharp 90 degree joints). I took screen shots of that and have them on my phone somewhere, and will add them later.
 
Here are the pics of those coolant pipes with the flathead on the dyno.
 

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You can run at TROG - I did this year with my avatar and 5-speed …… had a blast!

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But they will not let you run without front brakes ….
 
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I agree with this, "Yep, can’t deny that effect, but the mechanical pumps will be much stronger in terms of moving fluid than the thermo siphoning effect. The system was never purged of air, so I’m hoping that was the issue, but who knows for sure at this point."

Regarding 90° versus 45° fittings:

" ... Two 45-degree fittings generally create less resistance than one 90-degree fitting,"

equivalent-length-screwed-fittings-feet.png


Long radius elbows R = 5D
 
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Agree. I tried to use as many 45 degree fittings as possible where practical. I also had to keep in mind that these 1 1/2” fittings were around CAN$40 ea. I think I have over $1K invested in copper pipe/fittings. It’s crazy!
The most restrictive part in the whole coolant system is probably the thermostats themselves, so not entirely sure if I’ll ever add them back. I will never operate this engine at anything close to below freezing temps so not sure if they’re really necessary. Fluid will by design will always flow from high pressure to low pressure, and despite the horrible physical layout at the tees, I think there still should be sufficient coolant flow. The radiator itself is designed for a 200 plus hp engine, so there should be no issue with it. If there is an issue, it will either be coolant flow or airflow, or maybe both.
 
Maybe it's just me, but when ever I have had trouble with an engine at initial start up, it's been a symptom of something wrong deep inside. I remember one time I rebuilt a Sachs snowmobile engine. I must have pulled that thing a hundred times without a snort. Finally, when it did start, it wiped out a chrome cylinder and the piston. It turned out to be a set of defective rings.

My advice is to start looking deeper if you can't get it cleared up right away. Don't just plow ahead.

Plus, I have an unrelated question. Why isn't there a big leak at the pipe junction in the bottom picture? Nobody fits pipe that well.:confused:
 
For sure will look into engine after next run if there seems to be an internal issue, will then dig deeper.
If you’re referring to the pics of the engine on the dyno, then yes, Ed had to re-weld the joint where the two curved pieces were joined. lol!
 
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