ETW Sealion

[Weldsol]

That radiator looks great. I am building a Sealion also and have been thinking about a radiator. would you consider sharing the particulars of your design?

Ron

Hi Ron here is a general layout for the rad no dimensions as you can build it to what ever size / material size you want what is not shown is the side plates ( you can see them on the pic's I posted ) as these will depend on what size and amount of fin plates.
If you have any queries send me a PM
Paul

 

[Steamchick]

Hi Paul, you have done a splendid job making this radiator. I was adding my pennorth about the ally rods I use (flux free) as some with blow-torches but not TIG may be interested in the jointing material and method.
Another engineer in the club made a 1 1/2" x 2" radiator by machining 5/16" square brass bar with his narrow parting tool to make thin fins, drilled for fluid flow, and 5 of these tubes made the radiator assembled to top and bottom tanks.
Except the radiator is too small for the waste heat from his engine. Looks nice to scale though, but limits running to 10 mins from cold.
I am sure there must be calculations to determine radiator size? (something another Engineer did at work, not in my box of tools!). Flucid flow, fluid CSA, Air flow, Air Fin surface area and gap CSA... etc. Some calculations will be the same as I did 40 odd years ago, on air-cooled electrical things, but lost from memory now...
Must look things up on't interweb....
K2.

 

[ozzie46]

Thanks Paul, I'm looking at maybe a radiator about 4"1/2 x 5"x 1/2 thick.

Ron

 

[Weldsol]

Finally got quite a bit done after a rubbish Christmas / January / February (my wife's mother died just a couple of days before Christmas so workshop time was a bit awkward)
So here is what I have managed to get done to date

Base board cut and pocket cut out for starter motor,
Starter switch gear put in a box,
Ignition system finished and boxed,(made to be detachable so it can be used for other engines)
Flywheel machined (had to removed 1/8"from the rear face) for sprag clutch bearing and belt pulley,
Starter motor mounting housing,
All now mounted including the radiator I have also fitted a regurgitation bottle to the the rad no fan is fitted at present as I'm not sure whether to go for mechanical or electric (I have left the crank nose long for a pulley if it ends up being mechanical)
My first try at getting it going was yesterday afternoon got a few pops & bangs and it would almost run, I noticed while looking down the carb, a couple of spit backs the firing order as per ETW was 1342 but then I remembered Basil had a similar thing so I swapped around so it's now 1243 and I lost the spit backs but it still would not get going.

So pulled the plugs and they were oiled up so gave them a clean out with lighter fluid put hem back then tried again.

This time I got a few steady pops (note I was playing with the mixture needle at the same time) then all hell broke loose on all four cylinders for about 3 or 4 sec's then it stopped cranked it again and got the same I think it is not pulling enough fuel (will try a bigger bore fuel pipe)

So not had it running long enough to do a vid, when I do I will put it on the site

One issue I will also look at is drilling the face of the flywheel close to the edge and insert several slugs of tungsten to replace the material I had to take off for the starter clutch

Paul

 

[Steamchick]

Ee lad! That's a proper job!
Well done!
K2

 

[Steamchick]

You need to check the compression on each cylinder - to get the correct firing sequence. - Just in case you have mis-timed something? We can all make mistakes, though it sounds like you have a near runner, so something is right.
K2

 

[Weldsol]

You need to check the compression on each cylinder - to get the correct firing sequence. - Just in case you have mis-timed something? We can all make mistakes, though it sounds like you have a near runner, so something is right.
K2

Yes you are correct re compression for firing sequence , my brain was telling me 1342 firing order as most of my apprenticeship was on Standard Triumph's and they were 1342 so that's my excuse I'm sure Fords were 1243
The cam timing was done by splitting the overlap on No4 to give me No1 firing and the distributor set with points just opening at TDC (I will be able to advance it a bit when I can get it for more than a few seconds.)
If you read ETW's notes he quotes "It is really immaterial whether the firing sequence of the cylinders is 1243 or 1342 as the difference only calls for the appropriate connections to the spark plugs" this is quoted in the cam production notes.

Paul

 

[Steamchick]

Hi Paul. I am probably being thick here.... but if the cam is set for 1342 for clockwise crank, you would have to reverse the rotation of the engine to have 1243 firing order.... and I understood that also to reverse the intake and exhausts.... I'm struggling to get my head around this! Just call me thick if I am wrong.
K2

 

[Steamchick]

As I worked in engine design for a few years in the Automotive sector, I did a lot on peripherals, but the direction of rotation and firing order didn't come onto my desk. But the cam chain design did, and was very specific to the engine's rotational direction. (Tight side versus slack side). So (not knowing the Sealion) I would expect the direction of rotation - ergo firing order - to be quite critical?
K2

 

[Weldsol]

As I worked in engine design for a few years in the Automotive sector, I did a lot on peripherals, but the direction of rotation and firing order didn't come onto my desk. But the cam chain design did, and was very specific to the engine's rotational direction. (Tight side versus slack side). So (not knowing the Sealion) I would expect the direction of rotation - ergo firing order - to be quite critical?
K2

In one respect you are correct as in chain drive as you say tight side vs slack side because of chain tensioner ( one exception would probably been the old mini A series as that had the two rubber bands on the cam gear which worked on centrifugal force.
In respect to the Sealion it is gear driven (4 gears including the crank one) and could actually be made to run either direction
But the fact He stated both firing orders in the cam jig section and earlier on in his words that the crank direction should be CCW when looking from the front of the engine. it would have made more sense in the camshaft jig section to specify that his settings produced a 1243 firing order for his preferred crank direction.
But Hey Ho firing order now sorted and to add to that my points /coil ignition system works ok with no stray HF and that by using the Minimag MIC1A control I didn't have to use tungsten points as it only has 10 milliamps across the points.

Paul

 

[Basil]

Very nice work Paul. Glad you got the firing order sorted. Rocking couples as I call them is always the easiest way for me to see the firing order. That is exhaust closing, intake opening for the particular cylinder and follow those every half crankshaft turn for a four cylinder. Of course these rocking couples are one crankshaft turn out from firing when setting your points. Apologies if I'm teaching to suck eggs. Excellent Job!

 

[Weldsol]

Very nice work Paul. Glad you got the firing order sorted. Rocking couples as I call them is always the easiest way for me to see the firing order. That is exhaust closing, intake opening for the particular cylinder and follow those every half crankshaft turn for a four cylinder. Of course these rocking couples are one crankshaft turn out from firing when setting your points. Apologies if I'm teaching to suck eggs. Excellent Job!

Hi Basil no need to apologise, and thank you for your info on the starter pulley's they worked out fine.
Paul

 

[Steamchick]

Well done Paul, a nice engine! - Just a "point" on the "points"... the contact deterioration (arc erosion) is caused by the reacting current from the coil causing feedback when the contacts break. This (as I guess you know, but some other readers may not?) is countered by the capacitor, so the current rushing back out of the coil rushes into the capacitor (Old car buffs call it a condenser). It's a natural current caused by the back EMF of the coil.
What we are trying to do is open the contact, so the stored energy (your 10mA rms) in the coil leaps out of the HV side across the spark plugs. But being energy that will escape every possible way, it also tries to rush back across the points from the LV side of the coil. This is the damaging current that literally "burns" the contacts... (Arc voltages cause iron molecules at over 2000 degrees C to burn in air). Steel contacts only last ~1000th of the life-time of platinum contacts (as on the Contact Breakers bought in the car spares shop). But if you polish off the arcing oxides from your steel contacts after each run I'm sure you'll manage. (I had a magneto on a Bike back in the 1970s with contacts that had had the platinum filed off by the previous owner. - I ran it on my bike, but cleaned the points every 200miles, or tank of fuel, until I managed to buy some new (maintenance free) parts.
But now you'll tell me the Minimag MIC1A control does the "heavy current switching" - and you are right. I was thinking of simple "old-fashioned" non-electronic systems. (These electronic things were only invented in the 1970s, after my troubles with old, knackered bits!).
N.B. On "non-electronic" systems, If the capacitor fails, the points will burn incredibly quickly and you won't get many sparks at the spark plugs, as they will all be across the contact breaker points. (Been there, had that!). I have also had a distributor cap that had worn (arc eroded) so much that the sparks could not get across the gap to get to the spark plugs! A new cap and rotor arm (Measurably better!) sorted that unreliability. (My temporary fix was a thick bead of solder on the rotor arm contact. That got me to work nicely, without the previous mis-fires, until the new parts arrived). Ever wondered what the black dust is that collects in distributor caps? Or inside contact breaker chambers? (Sorry, stupid question, no-one does that!) - It is the vaporised metal from the contact arcs. - Being metallic oxides it also encourages flash-over inside distributor caps, from the high spark voltage there. So "Clean Caps" are best!
Hope my attempts at not "talking in electrical terms" helped some understand this? I can explain impedance, leading and trailing voltages and currents, but it confuses some non-electrical people.
K2

 

[awake]

Paul, I am sorry to hear about your loss.