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[DBS88]

The oil pump is driven directly from the engines crankshaft, so a 1 to 1 ratio, the first photo shows the pump as its been removed from the engine assembly.
The oiling system use three valves, the first is a non return valve at the base of the pump, the cam driven piston forces oil past the stainless steel ball and into a pipe - second photo.
The pipe carries oil up to a second valve attached to the top of the oiling cup. The valve lifts and allowing oil to pass to another pipe, at the same time excess oil is also returned via an overflow back to the oil reservoir - third and fourth photo
The pipe from the second valve carries the oil to the metering valve, which is a needle valve with a lock nut, adjusting the needle valve controls how much oil passes into the steam line. It is the excess Oil that can't pass the needle valve on each pump stroke that is returned to the reservoir. Photo 5, 6 and 7 show the steam line, the oil arrives at the bottom of the red valve body then passes into the steam line.
Hope this makes sense?

[1967Brutus]

It does make sense...

I would have expected that the oil flow would be controlled by throttling the return to the tank, that way forcing oil into the steam line, but the other way around also works, I guess.

[DBS88]

Here is a better photo showing the pipe the carries the oil from the valve at the top of the steam oil reservoir to the metering valve and into the steam line.


The reassembled oil pump was reinstalled and connected to the engines crankshaft. Then using a cordless drill to slowly rotate the engine the operation of the pump was checked, oil passed up the pipe and to the regulator and also out via the overflow back into the oil resivoir - success!


No, not success, the oil did not enter the steam line, the regulator was either blocked or closed. I therefore dissassembeled the regulator, cleaned it and reassesmbled it. I then set the regulator so I could hear air passing through it, knowing this would allow too much oil to pass. When I turned the engine over again, oil passed into the steam line, so 3 problems with the oil pump had been fixed.


The last job with the oil pump is to finalise the the oil flow to the steam line, which will be trial and error, by screwing down the regulator a bit at a time until the full oil reservoir takes an hour to an hour and a half to reach empty

[1967Brutus]

which will be trial and error, by screwing down the regulator a bit at a time until the full oil reservoir takes an hour to an hour and a half to reach empty

no different than an adjustable displacement oiler, or even the cylinder lubricators of the big marine twostroke diesels I used to work with...

Setting lubrication rate on those took me several days (engine running 24 hr/day) if I had to do it inbetween jobs, and at least 5 or 6 hours if I could focus on just that job alone (which was rare...).

[DBS88]

Now the pump is working and reinstalled, here are the instructions for priming and setting it. Before running the oil pump, it needs to be primed using the supplied syringe to force steam oil, via the hole in the bottom of the oil reservoir, through the valves up into the steam line. The reservoir is then filled with steam oil up to the level of the overflow.
The oil pumps metering valve had previously been set by the factory. To reset the valve back to the factory settings it is necessary to make small adjustments. Turning the valve clockwise 5 degrees at a time, to reduce the oil flow until the reservoir supplies oil for more than 60 minutes, but less than 90 mins.

[DBS88]

Here is only the third photo that I have come across of Countess, this version of Countess has a white hull, the previous photos showed a Countess with a green hull. My thanks go to a good friend and fellow Mayhem contributor for sending me information that include this new picture, your help and assistance is valued and appreciated.


If you know someone with a Countess or you have photos, plans, parts for a Countess, please do get in touch, thank you

[Mege66]

Hello David,
That's an interesting photo. Is that little thing to the left of the Countess a Lady Jane?

Did Maxwell Hemmens actually make all the hulls himself?
The colored surfaces are of absolutely unsurpassed quality

[DBS88]

Re the Photo, Yes the boat to the bottom left of the photo is Lady Jane, in the front and centre is The Countess, and in the back of the photo is Formidable.


The Hemmens hulls are of a very good quality, they are so solid. I previously owned a version of Formidable that used the GRP resin hull, it was stunning. I now have the plank on frame version of Formidable, which again is a joy to see.


Countess was offered with a GRP Hull, as a kit, in 1995, the price for the kit was £635, to which the cost of your choice of engine and boiler had to be added.
Countess was planned from January 1993 to also be offered as a plank on frame version, however, in the 1995 price list shows the POF version with a price to be advised, so not sure whether the POF version was actually available.


Re the manufacturer of the GRP Hulls for the range of Boats that Hemmens offered, Lady Jane, Skeandu, Rovuma, Formidable, Chimaera, Yvonne, Countess and Elmira, I am not aware of who it was, hopefully someone on the Forum will be able to advise us whether it was Hemmens or someone else on behalf of Hemmens manufactured the hulls.

[pipercub1772]

Hi i built the formidable late 80's still have it they were sold under the name of ocean models he did 3 different limited edition kits only, very basic in them days they had formidable glass fibre and pof,skeandu glass and pof and yvonne thames tug pof,cost of formidable in 1992 pof £245.00 ,glass fibre £212.00 ,think they sold out to hemmmens Not even sure if formidable was marketed even earlier by a company called marvon models but could be wrong on that.

[pipercub1772]

When John passed away his family sold most of his left over stock etc and quite a few of his hulls pof and grp hulls were
given to Leeds model boat club who sold a few off unfortunately none are left where is other stock went to i really don't know ,The Max 4 in this post is i think a testament to a extremely talented model steam engineer who in my opinion produced some of the most exceptional steam models both in appearance and quality,A great pity another steam manufacturer is lost to the modeling world,regards Allan .

[DBS88]

Allan, thank you so much for sharing your Hemmens experience and the background information on the model boats that were being sold by Mr Hemmens. As you say, he was indeed a really good engineer, the V4 really is a masterpiece and its a shame to have lost such a good UK manufacturer of model steam engines.

[DBS88]

I have been asked about the weight of the Max V4 Steam Plant, the boiler is 3 1/2 inches or 90mm dia so has a larger diameter than the boiler supplied with some Max 2 Steam plants - I weighed the plant to confirm the weight - it does have water in the boiler and gas in the tank, it is near enough 5kg.


I also notice that the poker burners used in the V4 boiler are different from those used in a Max 2 boiler that I have. The V4 burners have slots, the burners on the Max 2 boiler I have drilled holes.

[RobertC]

I also notice that the poker burners used in the V4 boiler are different from those used in a Max 2 boiler that I have. The V4 burners have slots, the burners on the Max 2 boiler I have drilled holes.

Presumably the slotted burners are louder than the drilled ones? My understanding is that slotted burners are quicker, and therefore cheaper to make. Rob

[pipercub1772]

The burners are superb quality and very well made however i myself have always thought they were lacking in efficiency
most of the Hemmens boilers i have had and used have been changed to ceramic type burners which improved the the performance it will be interesting going forward to see how they perform with the v4 ,.Allan

[DBS88]

Re the slots or drilled burners, I can definitely see that the slotted burners would cost less to manufacture, will experiment to see which performs best.


When the pokers were shaped for the ceramic burner, may I ask if the ceramic burner made a high pitched whistle noise? From photos I have seen where a ceramic burner has been used it looks like the secondary air holes in the skirt of the ceramic burner are being restricted or blocked by the end of the flue that the burner has been slid onto. These burners work better if they are fitted inside the flue rather than over the flue, when inside the flue the airway for secondary air is clear. Restricting the secondary air tends to cause a high pitched howling and poor combustion resulting in more carbon monoxide being produced.

[Mege66]

I have several Hemmens boilers which are fired using ceramic burners without restriction of secondary air. None of them howls. See the V4 in action with a ceramic burners without restriction: https://www.youtube.com/watch?v=XEvS3H9veR8

[DBS88]

Test run with slotted burners - I filled the boiler to about 50% and ran it with the slotted poker burners. The gas was turned up full. At


5 minutes the pressure was 30psi,
6 mins at 45psi, at
6mins 45 seconds at 60psi and at
7mins 25 seconds 75psi was achieved.


When everything is back at room temperature the test will be repeated with the other burners, the ones with the holes. I did not passed any steam so the boilers water level should be unchanged in readiness for the test.


Prior to the test run the burners were de-burred internally, cleaned and set up in accordance with the instructions. The No5 gas jets were also checked and cleaned.

[DBS88]

Before running the test with the poker burners with drilled holes rather than slots, the burners needed to be set up. I removed the slotted burners and screwed the drilled pokers onto the same manifold and gas jets, so the only change was from slotted to drilled burners. It was also nescessary to ensure the burners were aligned correctly as indicated in the boilers instructions.


The drilled burners were also de-burred internally in the same way the slotted burners were, every hole was cleaned and every hole was de-burred, then the burner was cleaned.


The test was run, the ambient temp in my basement was unchanged from the previous test. I fired the boiler, turned up the gas to full and timed how long it took to reach, 30, 45, 60 and 75 psi. It was surprising how much quicker the drilled burners achieved these pressures.

[1967Brutus]

I am a bit surprised about the time it takes to run the pressure up from 30 psi to 45 and further...

It seems a bit slow to me... Even the drilled burner, 55 seconds to run the pressure up 15 psi against a closed valve (AKA no steam demand).
Without steam demand there is barely any evaporation going on, which is THE big "heat absorber".


On my own set-up, at 30 psi, full burner literally is mere seconds (10 or so) to reach 45 psi, where the safety blows.

I would think burner capacity is a bit low in relation to the boiler volume?