Water jacket diagram

[Hugz]

Hi, Started up a WSC only to find severely restricted water reticulation. Done the backwash with hose (found a mercury flusher hose head fits neatly into seagull water outlet giving more pressure) to no avail. Started the descaling treatment. Removed waterpump housing and poured descaler in water tube as well as outlet. Left for 24 hours and flushed again. Marginally better. Will do a few more applications. Now here is the question. Does the water have more than one path after entering the barrel before exiting? Is there a diagram of the water cavities available? I've yet to remove a head without shearing the bolts so am loath to go down this path. Fortunately have a spare barrel if need be. The descaler is 99% sulphamic acid in a granual form. They (the manufacturers) recommend one tablespoon to one litre of water. Would a stronger mix work better? Also they warn against prolonged use with copper, should I keep it away from pipe?

http://www.hillmark.com.au/products/hil ... ers/scalex

Thanks Hugo

[charlesp]

There's no diagram of the water paths in the Century block that I know of. The water doesn't just have 'paths' it fills the whole water jacket and is released from the top adjacent to the cylinder head. It's likely that any blockage will be in that area.

I certainly sympathise about winding the studs off the head. Perhaps you will do better if you use head on the cast iron block to assist the loosening process, and don't apply too much strength to the spanner/socket.

Sometimes a blocked set of waterways is dead easy, with a soft brown gunk; usually the stuff sets like cement and has to be chipped out.

I have not used descaler. It's possible it may work, of course, but you can never examine the block to see exactly what's going on.

[Hugz]

I wonder if I should get all scientific and measure the volume of water in a good block compared to this one. Didn't seem to take much.

thanks Hugo

[phil]

If you check John's site under FAQs, do I need a new impeller?, there is a picture of a 102 cc cylinder with the head off.

[Hugz]

Thanks Phil, I had a look at that before but still wondered what went on behind. If the head bolts do indeed penetrate through the water jacket then there is more than meets the eye.

Cheers Hugo.

[40TPI]

If the head bolts do indeed penetrate through the water jacket .......

They do, and so do the crankcase studs at the other end.

So just for sport, the answer measured to overflowing as per the pic, is 145 cc of water. This is a pretty reasonably cleaned out 1980 EFNR Silver Century/Model 90 block. Volume is higher than factory original because of the pile of crud that came out! This block also has new stainless crankcase studs on the other end which may be a few mm deeper than std factory so this will work the other way on volume.

The structure is very much a cylinder supported by the inlet and outlet ports and also linked to the outer wall at the top and bottom corners.

Edit:

FWIW I found my success rate at removing head bolts/crankcase studs without shearing improved in direct proportion to the size of propane torch employed and also the length of block pre-heating time .......

Regards

Peter

[Hugz]

Thanks Peter for your trouble. Much appreciated. The volume data certainly will give a better idea of what is going on in the blocks. I will persevere with the descaling application as, hopefully, it will break down crud in the unaccessible chambers.

Phil (Canada) was kind enough to forward a picture of an exposed water jacket. Thanks Phil.

[40TPI]

Another "sectioned view" through a Silver Century block might throw a little more light. Not the pretty BS type of sectioned motor but it does illustrate how the central cylinder is linked to the outer walls via the inlet, exhaust and crankcase transfer
Most of the outer walls have frosted off/been hammered away. The remaining lump has been slit on either side with an angle grinder and the block then split with a cold chisel and a heavy lump hammer! The piston and rings were salvaged and cleaned up well...



And with the RH lump turned over to see the inlet port and the threaded hole for a cylinder head bolt going all the way through to the waterway..........



And finally a professionally sectioned Silver Century EFNR at the RAF Ibsley show last Sunday! The gear lever unfortunately obscures the top of the crankcase transfer.



Regards

Peter

[Vic]

A sulphamic acid based descaler will be good at removing limescale but a concentration of 1 tablespoonful (about 25grams if rounded) in a litre is quite dilute so a heavily scaled block will need several treatments at that concentration. To put it into perspective sulphamic acid will only remove approx half its own weight of limescale so the whole of your 25g will only remove about 12 g.
Sulphamic acid is only a weak acid so the reaction will be slow compared with a strong acid such as hydrochloric but it could be speeded up by using a higher concentration or by warming.

The pictures however show little evidence of limescale but a lot of rust. It may well be that a descaler based on organic acids will be more effective than sulphamic acid although being weaker they will react even more slowly and will almost certainly need warming.

Possibly another use for oxalic acid.

[mick r]

Fortunately have a spare barrel if need be.

OK then, this will almost guarantee that the head bolts will come out.
(If you did not have a spare, the reverse would would apply, and in all probability all 4 would snap).
Known as 1 of Murphy's laws.

Regards the descaling with chemicals,
this is fine after the "big bits" have been removed.
Main risk is that if you "naff about" and don't get into the warerways via the head holes and break up all the "big bits" of scale, every time you use it, you run the risk of a lump of scale being moved by the water pressure and blocking the outlet hole.

Regards removing the head bolts with heat,
It will help to heat the unit first, but remember that the head will expand faster than the block, so if you apply heat, ensure it has cooled prior to un-doing the bolts, or they will be even tighter.

Regards,
Mick.

[Hugz]

Its a bluudy Rippa!!!!

As you might have guessed I'm getting some positive results and while it still is not cooling enough to use, the results are definitely promising. I've acid treated it twice and at one stage even had a continuous flow. At this rate I'll probably have to do it many times but sure beats shearing studs. I believe this treatment maybe preferable to chipping away as it reaches and clears all chambers in the block. I'm certainly considering doing a few more of my motors.

As Mick mentioned there is a risk of debris blocking it again but with continuous douching she should be free of foreign matter.

Vic mentioned that oxalic acid may work as well, so I'm thinking it might be an idea if we can get hold of some crud the next time someone is chipping and do some acid trials out of the motor to see what is more effective in breaking it down..... any volunteers??

Acid Man!

[charlesp]

A few decades ago 'Acid' meant something different of course, and that brought to mind the day before yesterday, when I went with Current Primary Woman and her 20 year old daughter to Gunwharf Quays in Portsmouth. Oh No! I can hear you cry, you sucker. But I needed a pair of shoes, so off I went.

Ye Gods, a mother and daughter team clothes shopping are far far worse than just one woman on her own. They giggle and veer off course, they offer unwanted and frequently contradictory advice about one's own purchases, and glare scornfully if you stop to look in a shop window full of expensive audio.

They have no plan of action, they buy stuff that they don't want, won't fit them, and that you dare not comment upon..

For years I thought that those guys with a guitar and a dog on a bit of string were homeless poverty stricken folks, now I realise they are the clever ones; they have gone shopping with multiple women! They take the dog and the guitar to keep them occupied while the girls are 'just popping into Ted Baker's to find a dress. Way to go, guys!

Anyway, after an afternoon of this torture not helped by temporary deafness (Thought I'd try eardrops to clear a bit of wax, leading to complete stone deaf left ear) we set off home.

CPW's daughter, strangely, likes my taste in music, and fired up the car CD player, which treated us to a quite loud (but for me right hand channel only) selection, including Stones, Hendrix, Neil Young, Van Morrison, etc etc. (The other Charles has a Hendrix number as his mobile ringtone).

We came to a halt outside her house, and she waited till my good ear was facing her.

'I'm a bit worried about you', says she frowning, 'All your music is about substance abuse!'

Oh dear, Charles in trouble again. And this from a woman who is struggling to work out why Thin Lizzie's famous number involves keeping
'Whiskey in a Giro'

Bless 'em

[Collector Inspector]

Hugo

How are you going with your block cleaning.

Here is a tip you may well like regarding acids and nasty quick else same "Fixes"

Acetic Acid is found in non citrus fruit and vegitables (Tomatoes) and in this case for you Vinegar. Vinegar is about 5% Acetic Acid and just loves rust and scale but will leave the base metal alone as the reaction basically "Stops" as below.

Vinegar contains acetic acid CH3COOH which reacts with rust FeOOH:

3CH3COOH + FeOOH --> Fe(CH3COO)3 + 2H2O

and iron (III) acetate Fe(CH3COO)3 is water soluble.

So, once all of the big chunks are removed fill it up with 100% white Vinegar, leave in the sun or warm place and come back in 24hrs. Maybe the occasional movement so as to relieve pockets of gas (Do not top up with more Vino if the levels go down as this annoys the reactions happening inside). Wait till next time.

Drain and flush with cold water to remove a black slime that indicates the reaction is working.

An interesting thing is that the Vinegar reacts really well with the organics in any mud or congealed sediment so if it starts emitting bubbles and frothy brown/yellow "Gunk" all over the place all the better!

Working well in 102 block I dug out yesterday. Actually is very easy on a 102. You just fill at the top of the block after removing air or bleeding from the flexy water pipe connection above the pump.

It is a slow process but that is cool as slow is always better in the long run.

If you try it, let me know?

Regards

C.I.

[Hugz]

Actually I'm about to try diluted mollases. And old cockies trick. Have no idea why it works but plenty of info if you google 'rust mollases'.

Thanks for your info tho.

Cheers Hugo

ps. I've finally recovered from Melbourne Cup week.... strewth, it was a tad wild!

[Collector Inspector]

Ah.....The beginnings of fine Bundy, how applicable to rusted Seagulls and "The Cup"

Molasses has a few acids but the one that reacts with "Rust" is Phosphoric Acid.

While it "Converts" Rust by turning it into a Phosphate of iron, it does not really "Remove it".

Heard of Ranex? It is 35% Phosphoric.

BAD news for Aluminium and once the Iron Phosphate is realised it is there forever impervious to everything.

Also, while we are on the subject of corrossion, there is nothing wrong with attaching a small sacrificial zinc anode to the gearbox (above the pump housing). Nice small single screw ones are available example Evinrude Johnson shop, that will do the job even when out of the water. 2008 4Hp one fits a treat!

C.I.

I spent the cup week in our south west surrounded by trees, rain, beers and great food. Forgot the Bundy...................