Saving Old Seagulls

what does the board think of this subject....
shall i run a short pipe or one that enters the water....which is best for the engine

I think the water runs perfectly alright without any extra pipework added on.

If you pipe it in to the water how are you going to tell if the intake is blocked. The out let works as a good tell tale

Run a short pipe or not the engine will not care
i did this on a silver century 102 style into the exhaust because i like it this way

http://www.youtube.com/watch?v=3jhK2RwT ... detailpage

I can't see any reason to change the way the cooling system works.

In fact I can only see such modifications as being pointless at best.

There might be a point Charles if the water introduced to the exhaust is taken from the problem pocket discussed in the rusty cylinder thread, providing it's done the same way Seagull did on the late model Centurys, if it enters the exhaust too high, you could risk exhaust pulses putting some of it back into the cylinder, hence the long copper tube Seagull used.

British Seagull were never scared of making a small modification that would improve their motors. I'm not sure the OP was intending to drill a hole into the 'problem pocket' or if he was just going to take a pipe from the coolant outlet, but there are considerations..

1) If you drain the water from your 'problem pocket' are you threatening the integrity of the water bath? Could you end up with unintentional hot-spots if the jacket fails to fill properly?

2) If you tap the coolant exit hole for a pipe are you not effectively restricting the flow by reducing the coolant exit diameter?

3) Does feeding the coolant off down a pipe reduce the flow again through friction effects?

4) Could a Siphon effect be introduced that might accelerate the flow?

5) What are the possible effects of back pressure from the exhaust?

British Seagull had a successful motor in the 102, one with a proven impeller/feed pipe/water jacket/coolant exhaust system. When they started producing Centuries they went for a much simplified system. It must have worked for them, because they kept making the things for years and years. Had they needed to take the coolant into the exhaust many of the components were sitting there on the shelf in front of them. They must have stuck with the simpler version for a reason.

If you alter any of those things you stand a good chance of altering the running temperature of the motor. Maybe it would run hotter, maybe cooler, it depends what you do and how you do it. But you stand very little chance of it running at the designed temperature.

So for me modified cooling systems are in the same category as the bizarre fetish for o-rings instead of cork in fuel taps, pan scrubbers stuffed up exhausts, weird transistorised bits for the ignition, people who insist on an 'improved' ignition timing, grinding the tips off propellors, those strange inline 'ignition boosters', and so on.

point taken if not broken leave alone lol

Good point Charles, I hadn't given any thought to any of these mods changing the running temperature of the motor!

Both of our researchs have shown that Seagull did a lot of work checking the flow & temperature of the coolant.

You can see from Niander's youtube vid that very little water is being discharged from his 102 tell tail, pumped by a Century impeller, perhaps it's missing the higher output from the 102 pump design.

I suspect that may be the case. There's another issue of course, to do with the partial clogging of water jackets.

Without a clear view of the whole coolant stream it's difficult to see exactly how much water is going round the system. Which means problems may be masked, early warning signs of a blockage may be ignored.

I'm unfashionably old-fashioned about this sort of thing, I know that. But I'm uncomfortable with any straying from the path of orthodox righteousness.

Hopefully more water is going down the exhaust pipe than is coming out of tell tale on the elbow.

But there is a positive pressure in the exhaust, how is the low pressure in the water return pipe going to overcome that?

There's no way of knowing.

Perhaps British Seagull moved away from the idea for a good reason?

One thing ive noticed is that the 102 outlets are so small
like half the size of a century block outlet
this is a bottle neck and will slow down /restrict the water coming out
in fact i believe the hole should be larger
which is what BS did with the century blocks

Then with the QB range they put water back down the exhaust, and had a short pipe on the head outlet.

I thought there were great benefits of water cooling the exhaust as it comes out of the cylinder.

H-A