[singleminded]

Hi all.

Interesting result of having changed the telltale spring for a slightly lighter one.
1st the tell tale pops out
2nd the bike no longer sumps as badly as it did.The oil used to exit the tank and onto the floor in 2 days,now it stays in the tank and after 2 weeks hardly any smoke on start up.
Nearly had the neighbours phoning the fire brigade once ..John

[singleminded]

Hi Vic..I'm running Morris Straight 40..John

[VicYouel]

I have been doing more studying and had few chats with Les Hobbs. I think we agree on the specification of the top end oil pressure spring. I will say something in the next Beaming issue.

The important thing is that the tell tail does stick out a good distance (like yours) under relatively low pressure otherwise the oil supply through the timing side shaft is cut off to the big end. I will try and determine a measurement when I get the opportunity. When it springs back it minimises sumping.

A worn plunger housing at the plunger end of the tell tail is undesirable...... one of mine has a thin o-ring added. There are signs that all my springs have been modified. It does sound to me as though you have solved your problem. What grade oil are you running by the way?

[VicYouel]

Vic
I looked in the gallery but I could not see the photos?  Did you post them and also you can post to this thread if that helps.
Graham

Graham, I found two of them under "my images" in the gallery..... loads of oil bits on an old copy of OBM

I do struggle uploading pictures from my disorganised Windows XP relic.

[singleminded]

I found a slightly softer spring in my spare timing cover..The telltale now pops out about 1/4 inch at 20 PSI..John

[shorrog]

Vic
I looked in the gallery but I could not see the photos?  Did you post them and also you can post to this thread if that helps.
Graham

[VicYouel]

Hello again John,

I have added a couple of pictures to the gallery showing pictures of my various tell tail bits.

All 4 of my engines are fitted with a number 50 jet at the top end and the upper springs are all similar measuring 0.175 inches diameter and 1.375 inches long. They retain a 1/4 inch diameter ball but the spring has a tendency to slip off and get trapped; careful assembly is essential. Seems a poor design to me.

Just a thought that your spring may be trapped thus releasing too much oil in to the rocker cover chambers. A spring filled with felt material should regulate the amount of oil flowing to the valve guides; this is retained by a captive screw with hole in it.

At the bottom end one spring which I know works measures 0.325 inches diameter and is 1 and 1/4 inches in length....... it is fairly soft in terms of pressure to compress. Clearly the spring in my number 2 Sunbeam is too strong and turned out to be too long as well.  I suspect it is not too critical as long it pops out under kick start type of pressures thus allowing oil to circulate.

Incidentally my Sunbeam handbook (10th edition second issue) states an oil pressure of 30/40llbs for the model 9 and lion.

As an aside I have been analysing my parts lists. The springs were changed in 1932 and then seem to be the same part number for later 1932 through to 1935/6.

I think a book could be written on this subject! I hope this helpful.

Vic

[singleminded]

The jet in the top elbow on mine is a 120..john

[VicYouel]

I have four top ends and various bottom ends. All my top elbows are the same with spring and ball. I can start to make some comparisons and deductions.  All mine have the same jet which has a number on it; I'll post the details when I get around to it. As for the spring mounted felt in the rocker cover..... well I guess it sort of works....... all a bit hit and miss.

Vic

[singleminded]

Yeesss..It's all very well for the parts list to state different springs for the 2 different top elbows(the same casting) but the marston factory parts dept closed a loonngg time ago,and I cannot workm out what the telltale spring pressure should be.The top elbow(I have both types) one has a spring and ball in it and I assume that this is to stop the oil draining from the pipe. I am not sure if the jet is the correct size but again I can find no reference to what it should be.
Even with the pressure that I am getting there is too much oil getting to the top end as it burns very nicely in the exhaust.
The arrangement for controlling to oil to the guides is also a connundrum as I cannot see how a spring pressing on a bit of felt can be a control system,but hey ho i'll live with it until it all becomes clear in the next world..John

[VicYouel]

My first model 9 rebuild using all the original bits that came with the bike when I acquired it in 1979 shows a pressure of over 100 psi initially and then settles to 40 or so.  I have done 200 miles on this machine but am a little concerned that not enough oil is getting to the top end through the clumsy felt oiling regulator.

My second rebuild hardly shows a pressure at all and the indicator hardly pops out. I am in the process of swapping oil gauges and also comparing the parts like the top end ball valve springs etc.

The parts lists for 1932 shows two different springs are fitted (parts 5461 and 7397) to the tell tail. Two different elbow connections are specified for the rocker box connection..... however they seem to use common parts......I'm confused right now.

You have asked a very interesting question.

I may take a while to provide further info and will place it in Beaming as this should be of general interest.

Cheerio for now

Vic

[singleminded]

Hi all.

Anyone know what the pressure of the telltale spring for a 1932 Mod 9A should be,and where might I get one..
The tell tale has never really popped out like it should and I do wonder if the housing/plunger is worn.I was getting a pretty steady 20PSI on the oil gauge with the tap set on 2. I went for a run to the Essex section meet at Finchingfield last Saturday and on the way back the gauge was moving between 10 and 20 PSI at will,need to investigate this!.
Bike went great though no signs of any mechanical noises that shouldn't be there,cruising at a nice steady 50 mph and pulling well.So if anyone knows where to get a new srpring and what the spec is please post here..John