Ford 300 Inline Six

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You're going to make a filter element for it aren't you?

I mean you went to all the trouble of making that FINE looking air cleaner, you're going to make it functional - right? Maybe a cut-up foam lawn-mower filter element? You want to get 100,000 miles out of that engine it's got to breathe clean air.

The return to tank line looks awfully close to the exhaust down-pipe, any concerns about the heat affecting the fuel lines? (Maybe there's more clearance than the picture makes it appear to have?)

Don
It's the camera angle making the fuel lines look so close to the exhaust. The natural curve in the return line along with the tubing loom keeps them both safely away from the heat. - Terry
 
Terry,

This might be a simple, inexpense, non-invasive way to measure RPM. The long black wire picks up the ignition signal inductively through the spark plug lead. The tach is programmable for many different engine cylinder configurations. Even if it is just used as a diagnostic tool, it is nice to have around.


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Terry,

This might be a simple, inexpense, non-invasive way to measure RPM. The long black wire picks up the ignition signal inductively through the spark plug lead. The tach is programmable for many different engine cylinder configurations. Even if it is just used as a diagnostic tool, it is nice to have around.


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Thanks! I just ordered one...
 
Hi Mayhugh1 !

I have a question ,
Does your engine have an oil pump ?
If not, is 20 cc of oil enough to lubricate the engine ?
Thanks !
 
Hi Mayhugh1 !

I have a question ,
Does your engine have an oil pump ?
If not, is 20 cc of oil enough to lubricate the engine ?
Thanks !
There's no oil pump. The way I determined the amount of oil to run in the sump was to run with the highest level of sump oil that would not smoke badly and spit oil out the exhaust. I don't think it's necessary to have a high oil level for the connecting rods to dip into. There will be plenty of windage in the crankcase to lube the moving parts in an engine that's not being asked to do real work. The pistons of a multi-cylinder engine moving up and down in their cylinders create alternating pressure and vacuum pulses inside the crankcase that create an oil storm that should lubricate everything well enough without overcoming the pistons' oil control scheme. One indication that this seems to be working is that the top-end is also wet with oil which must be getting dragged along with the vented gasses through the filler cap. ymmv - Terry
 
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One indication that this seems to be working is that the top-end is also wet with oil which must be getting dragged along with the vented gasses through the filler cap.
Well there's your next project isn't it? You've obviously got to build a working PCV valve to vent that airborne oil back into the intake, can't let it be slobbering all over that frabjus valve cover.

Don
 
Well there's your next project isn't it? You've obviously got to build a working PCV valve to vent that airborne oil back into the intake, can't let it be slobbering all over that frabjus valve cover.

Don
Eh, as the owner of two 300's in full scale....they really just don't look right unless they're soaked stem to stern in oil. They're notorious for valve cover and sideplate leaks in particular. One of mine leaks so much oil it doesn't even get oil changes anymore because the oil doesn't stay in the bloody thing long enough to need changed in the first place!

PCV would be a nice scale detail, but I fear it might end up like my other 300, in that it would be pushing so much oil down the carb that air filters turn jet black within a month. That one doesn't really leak very much anymore as I've replaced the valve cover and sideplate gaskets within the last ten years, but it also has 350k miles on it and the top end is worn plumb out so it has a metric -beep-load of blowby pushing oil mist out the PCV hose and down the carb. Given this model is known to lubricate the valve train by pushing oil mist quite heavily into the valve cover it'd probably be no different.

Damn good engines though. I love them to death, no matter the scale! I would love to hear mayhugh's example running under heavy load; it makes them sing such a beautiful song!
 
"One of mine leaks so much oil it doesn't even get oil changes anymore because the oil doesn't stay in the bloody thing long enough to need changed in the first place! "

This is a common misconception. The leaks in the engine are all acting like filters, so while oil is leaking out, the sludge and particles which accumulate in the oil are staying in the e
 
The inductive tach recommended by Eccentric arrived. Mine's a slightly different model but still very easy to set up for a 6 cylinder engine (or any other number of cylinders). From its lope I was sure I had the engine idling at 800-900 rpm, but the tach kept telling me the real number was nearly twice that. I thought a setup issue or electrical noise was causing too-high readings, but after a lot of troubleshooting I was finally convinced the tach was working as it should.

With my confidence in the engine growing, the carburetor was retuned for a top end of 5k rpm even though full throttle was 7k. These higher speeds required the fuel pump to be bumped up in order to maintain a constant level of fuel in the bowl. Still, the air bleed adjustment didn't seem to have much effect.

Carburetor tuning doesn't seem to be affected by the air cleaner. Suction through the intake snout is noticeable though, and the engine will immediately stall when it's covered. It'll be used as a choke during cool weather starting.

With the rocker cover and air cleaner removed, I took a number of IR photos over various surfaces of the engine during and after a two minute run. The first two photos are overviews of both sides of the engine as viewed from its rear taken at the end of the run. The siamese'd intake manifold eventually rises to the same temperature as the exhaust manifold which is some 250F.

The third photo is a closeup of the intake and exhaust manifold surfaces taken well into the run. The intake runners which are cooled by fuel while the engine is running are some 20F cooler than the exhaust runners. All three photos show the carburetor as the coolest part of the engine - most likely a result of the cooling provided by the recirculating fuel. The fourth photo shows the effect of manifold heat on the carburetor about midway through the run. Although the temperature of the carburetor's base has risen, the important area around the Venturi remains cool to help keep tuning consistent.

The fifth photo is a closeup view of the top surfaces of the head taken near the end of the run. It's 177F temperature is representative of the hotspots between the rocker assemblies and above the combustion chambers along the entire length of the head. These hotspots are uniform across the width of the head despite the fact that one of the head's longitudinal coolant passages was blocked during construction and is non-functional.

The sixth photo shows the temperature gradient across the front face of the radiator at some 1-1/2 minutes into the run. There's a 10F gradient from top to bottom with the hottest area at the top of the radiator being some 140F. This temperature is 30F-40F cooler than the hotspots in the head. This gradient all but disappears during a longer run when the face of the radiator settles out to 135F.

The last photo is a view of the port side of the engine midway into the run. With the side of the head at 155F, the crankcase is a fairly uniform 143F with the oil pan some 20F cooler. All in all, the photos show a pretty effective cooling system that I wasn't expecting and head temperatures considerably lower than I expected.

This build has been so much fun that I'm having trouble ending it. I never considered designing a pcv valve, but I did press out a brass 2-56 wing nut for the air cleaner cover which I then nickel plated. That nut is similar to the ones used on some Ford engines from the same period. - Terry

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Ah come on Terry you're killing us here! When are we going to see the video?
 
Sorry If I missed it in previous posts, but how are you taking the IR photo's ?
That is exceptional in all respects. Thank as always for your excellent work and meaningful
and educational posts. Thank you.
 
Sorry If I missed it in previous posts, but how are you taking the IR photo's ?
That is exceptional in all respects. Thank as always for your excellent work and meaningful
and educational posts. Thank you.
I used an IR camera that my oldest son gave me for Christmas several years ago. It's very similar to this one:

https://www.amazon.com/Resolution-P...=1653851827&sprefix=ir+camera,aps,163&sr=8-16
I used it to measure the effectiveness of the finless radiator that I designed for my Offy, but I got so wrapped up with its tuning and oiling system that I forgot to post any picture results. Since I used a similar radiator on the Ford, I thought the photos might be of interest. - Terry
 
Simply outstanding!
Beautiful craftsmanship all around.

What’s next?
I enjoy following along everyone of your builds.

Sid
 
Like I said : Any engine you do is really great !
I love how you do everything perfectly , that's something I haven't done yet - hopefully one day..
Thanks for share .
 
FANTASTIC, What a wonderful rendition. It runs great. Thanks for the great documentation.
 
Fantastic. Wonderful, Super.

I've been waiting to see it running and I am glad to see it in such glory.

Whatever you do next, I'll be watching.

--ShopShoe
 
great job!
i enjoyed this thread very much - 6 cylinder in-line is my favourite type of engine.
thanks a lot for your time and for educating all of us following your thread.
all the best in your next project!
branislav
 
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