Dominator 88

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Is there a steady stream of return oil, or is air returning too?
Is the head supply coming from the return pipe?
It's fairly steady, although I will admit, it's not as strong as on the Velos - but again, completely different engines, so you cant really compare.

Yes - head supply is coming from a t-piece in the return pipe.
 
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It's fairly steady, although I will admit, it's not as strong as on the Velos - but again, completely different engines, so you cant really compare.

Yes - head supply is coming from a t-piece in the return pipe.
Depends if you still have the 3 start oil pump worm (nothing wrong with that) or the 6 start.
Stupid question I know, but as you got this bike half in bits, have you got the oil pipes from the oil tank connected up the wrong way round ?
 
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Depends if you still have the 3 start oil pump worm (nothing wrong with that) or the 6 start.
Stupid question I know, but as you got this bike half in bits, have you got the oil pipes from the oil tank connected up the wrong way round ?
Good question - I did ask that myself! As far as I can ascertain they are correct checking against the Haynes Manual - I would be lying if I told you from memory which one went where, but I will check tonight and confirm.
 
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Okies, just a thought as I run either straight 40 or 20/50. Not sure how warm you are but 30 seems a little thin. I'm sure others may disagree. Good luck.
 
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Good question - I did ask that myself! As far as I can ascertain they are correct checking against the Haynes Manual - I would be lying if I told you from memory which one went where, but I will check tonight and confirm.
Looking at my reference photos - there is a pipe from the bottom of the oil tank with a tap, and that goes to the outside connection of the crankcase. The return line is connected to the inside connection on the crankcase and that goes to a T-piece - one pipe to the top of the head where it splits and feeds through two banjo bolts into the top of the head, and the other back to the top of the oil tank where If I open the oil tank lid I can see the oil returning.
 
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Sounds like your pipes are correct, sister in law is in Oz, 35degrees at mo. 7 here. Hope you get sorted and there is plenty of advice on here.
 
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Your engine is 1953...very old! I even have an old 50xxx.
I only use 50W summer-40W winter (under 40deg F).
Curious, Is your oil pump early zinc body narrow gears or cast iron...possible late wide gears ?
The oil level is automatically held to top of crankshaft gear due to drain hole at rear of timing chest.
I do not believe that engine would have originally had a tach drive timing cover.... but not a problem if there.
The dynamo engines have no ability to convert to alternator without a huge custom machined adaptor project or Alton alternator in a dynamo package. Gear for lucas dynamo is "norton" part and not lucas part like on BSA or triumph.
The 12 or 122 or sometimes called 12-2 by norton, have a timing disc on the end of the cam and help to keep crankcase lower than free breathing if missing. This timing disc is in all NHT up to 20M3S engines. It is reducing effectiveness as the engines grew in size. outlet on rear of engine.
post 27 The oil line to the top of the head is rocker oilers under a casual "puke" LOW pressure system.

more to follow if desired
 
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I have run my 99 on all sorts of oil, and it does not seem to make much difference. For many years on diesel HD 30 , currently on 10/40 fully synthetic which I doubt anyone else has tried. In your climate 40 or 50 monograde is good . I have problems with kickstarting so the lower resistance is helpfull. If we get a proper summer I will switch to 20/50.
 
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currently on 10/40 fully synthetic which I doubt anyone else has tried.
I use Rock Oil 10/40 Synthetic in my 1958 99 and have done for a while. It was a recommendation from Pete Lovell as he has stripped a few Nortons down and noticed very little wear.
I am now, however, influenced by Jim Comstock's (Comnoz) oil testing marathon.
 
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I only use 50W summer-40W winter (under 40deg F).
The rules to go by that I offer is as follows:
1. Any oil is better than NO oil
2. Clean oil is better than dirty oil

3. after those 2 it becomes just that... an opinion
I'm in no way claiming my selection is perfect or absolute and you must obey:p
I use those for the high zinc additive.
Jim's oil test thread bears reading for further guidance for the selection process.
 
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I read all of Jims oil threads with much interest however it soon became apparent that the running conditions that the thread was aimed to cover bear little resemblance to the world I occupy. Cams and followers are everlasting and getting the motor and oil up to temperature takes an hour minimum. Neglecting oil changes is about the worst thing in those conditions.
 
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It's fairly steady, although I will admit, it's not as strong as on the Velos - but again, completely different engines, so you cant really compare.
Yes - head supply is coming from a t-piece in the return pipe.
The return pump has more capacity than the feed pump. You shall see an intermittent flow returning to the tank, when the crankcase is cleared of excessive oil, can take some minutes. I've not worked on a Domi with top feed from return since the stone age, so I can't clearly remember it. The problem you have might be that return pipe in the tank is too restricted, thus feeding the top more, instead of clearing the sump. Could be a leaking pump too. The crankcase shall have an amount of oil in it after a run, I think 1/2 a pint.

Edit. If idling long time, block the return outlet with your finger a couple of seconds to give the rockers some extra oil.
 
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I took the sump plug out of my running 99 and watched for a while, very little visible oil flow, spits and flecs only . Half a pint would probably gather after a few days draining down.
 
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Hi All - It's been a bit busy the last few evenings, so I'm going to tackle it again on this weekend - will check all the points mentioned here and then hopefully have some feedback for everyone on Monday.
 
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have you drained the sump, then started it, as suggested...what result??
I had forgotten to replace the sump plug after draining the oil and refilling the tank and starting up. Once I realised the error I was interested in watching exactly how much oil would be expelled and how long it would take for the black oil in the crank to run clean. No real oil flow ,spits and flecs, a couple of mins before the colour improved. Replaced the plug and then disconnected the tank return ,again a couple of mins running to get clear oil . Forgot to flush the low pressure head feed!!. Ah well. Next time. Snowing now, too cold for the garage, and am not too well after a flight from the med in a plane with a load of Asians, don't tell anyone!.Or they will come and take me away .
 
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Interesting that Dommie Nator also uses 10/40 synth. If Pete Lovell recommends it that's good enough for me. (at least till my free stock runs out!)
 

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