Hi all
I have a bad oil leak between the primary drive cover and the engine sprocket, I cleaned everything off to see where it is coming from and it is not coming from the seal between the outer primary drive case and inner, it is coming from behind the primary drive cover, I am thinking it is the crank oil seal
Do people concur or could it be something else, and if it is the crank oil seal what is the procedure to fit a new one
Thanks
Mike
I don't think a failed crank oil seal on a plunger can leak to the outside world. It should leak into the primary chain case. It should be a solid casting behind the cover. Are you sure it's not either the chain case drain screw (lowest cover screw) or the level screw? They leak badly if the small fibre washers are missing. I put gasket sealant on them as well to be safe.
Adrian.
Thanks Jackson
I will clean everything off again and try to see where it is coming from however it is difficult to see
Hope you are correct
Thanks
Mike
Hi Mike,
How are you getting on with finding the leak? The plunger primary can only leak either from the drain/level screws as mentioned by Adrian or the joint face between on the primary cover. The joint face is quite narrow so a leak is not surprising but it is possible that a dribble from the engine breather could run down and drip off the bottom of the primary case. Ditto a leaky seal behind the clutch or the gear box.
After wiping off any oil does it leak when just standing, on side stand, on main stand or only after being run?
I suppose the other thing to try and determine is if it is engine, primary or gearbox oil. Engine oil is more likely to be contaminated and be 'dirty' looking, gearbox oil probably quite clean and thicker, primary oil should be relatively clean and thinner than either of the others.
Dave.
Mike,
I really hope it is travelling from somewhere else or the screws.
If it really is behind the chaincase, it will be expensive.
Good point about engine breather though from Dave. It could easily be running down from there. Also, the story is that they expel oil from the breather if they have wet sumped. I stopped mine doing it by fitting a SRM oil pump.
Adrian
Thanks for the info guys
The oil is dirty and a lot of it, only leaks when running, I will investigate the breather first and hope its not the gearbox although the oil is black not clean
I have a Austin seven in the way at the moment so can't get to the bike easily but will clean everything down and start her up again to see if I can see it
Thanks
Mike
Hi Mike, Just to back up the others, when I recently ran my '54 Flash having had the chaincase off for a few weeks for other problems, I had a build up in the sump and this was blown out off the breather pipe, so much that I could not tell where from - what a mess. After cleaning down, finding nothing and looking in the oil tank, it became obvious. Yours sound just like it. Hope so.
Thanks for all the help I will check out the wet sumping issues as soon as I can and report back
Thanks
Mike
Looked at the oil level in the tank, whoa ! Hardly anything in there! so definitely wet sumping, breather comes out below the tool box but doesn't look like it hasn't been leaking though ?
I will drain the oil out and refill the tank and start her up again hopefully it may cure it
Mike
Sounds promising. Good luck.
Adrian.
Hi Mike,
The breather being referred to is part of the crankcase and exits just behind the primary case and crank case.
There is often a pipe fitted and I think this was standard on the plunger. You may be able to feel it or you will have to try to look under the engine.
107 is the pipe, 105/5/6 is the clip and nut and bolt to hold it.
Dave.
Thanks Dave
All is not lost ! this is obviously the issue, thanks very much for pointing this out much appreciated
looking at replacing the oil pump at the moment to reduce wet sumping issues, was going to fit the SRM one but there are none out there, does anybody know when these will become available again?
Hi Mike,
Best to contact SRM direct as they seem to be out of stock for all pumps.
Dave.
When I wanted one they were out of stock, so I got in touch, turned out they were making them the next week. It took a fortnight all told because they test them before sending them out.definitely worth getting in touch.
Hi All contacted SRM, and was told there will be some available in a couple of weeks, but then got an email to say they had one available right away if I wanted it, so I have purchased it, will be fitting it later this week, hope this will stop the wet sumping issue
The one in currently on the bike was leaking badly inside the primary cover the last time I looked so hopefully the new one will be a cure for that also
Mike
Well the gold flash does not leak badly any more, thanks to a new SRM oil pump fitted, the old oil pump was not in a good state and the engine wet sumped very badly, leading me to buy a new pump
This bike has been restored by an "engineer" however I have had no end of problems getting it reliable with the Dynamo not charging, the ignition timing way out,the Magneto breaking down when the bike got hot, the gearbox not selecting gears etc, and along the way I replaced the primary drive chain because there was no more adjustment left, who would rebuild a bike and not replace a worn out primary chain ?, and then the oil pump, when I took it out it was leaking very badly and had a washer behind one of the bolt holes to try and get it to bolt down flat to the face of the casting, I checked the oil pump face for flatness and was shocked at how warped it was hence the washer
in summary I have spent more time repairing it than riding it, 150 miles in six months and I am still trying to get the timing spot on with the new Thorspark electronic ignition, I set it up statically with the plug hole measurement timing device at 9mm before TDC fully advance and then use a meter on continuity whilst turning the the trigger unit until I hear the meter buzz and then finely adjust the trigger unit until the meter is just about to buzz, how ever when starting the bike it seems very retarded and I can not seem to get it just right by adjusting the trigger unit again, very frustrating, has anybody got any tricks with this set up ?
Thorspark say to use a strobe with a mark on the primary drive somewhere but I find this is difficult to do and if you are going to stop the engine and adjust the trigger unit every time to get the strobe to line up with the mark surely that is the same as doing it statically until you can feel and hear the engine is timed correctly ?
my next move is to try setting the ignition statically one degree advanced at a time until I feel it is correct, IE 10 mm on the timing tool and then 11 etc
Hopefully I will get the bike usable before summer ends
Mike
The standard BSA pump does have a thin fibre washer behind the pump where the first bolt goes through. Leaving this out would distort the pump. I believe the SRM pump doesn't need this.
around 9mm btdc on the timing tool is about right. if your timing is not correct something must be moving as you tighten the atd in the fully advanced position. the atd will not advance until between 2,000 to 3,000 rpm anyway so how does it run through the gears up to 50mph? a manual mag pinion is an option for you to make timing easier and a quicker tick over.
Thanks Eddy
I have been thinking about the timing, I am setting it up with it fully advanced and then trying to adjust the trigger unit after wards, without wedging the advance open again ie primary cover back on, do you think I need to leave the primary cover off and keep wedging the advance Everytime I adjust thee trigger unit,?
by the way setting up the ignition timing when the mag was being used I did not have an issue
hi captain mike, do you mean the timing side cover, not primary? yes find a wedge , wood or bolt and leave in the atd until all tight. with a mag i mark the points unit against the mag body in pen to check the points havnt slipped when fully tight. i guess you can do the same with electronic rotor to body.
Hi Mike,
Assuming that the Thorspark EI is fully advanced as the default setting as with Boyer and Pazon try static timing first. Using a rod with the relevant marks on set the piston to the correct BTDC position and set the rotor and stator as per the Thorspark instructions. It is best if the screw in the slot is about mid point to give plenty of scope to tweek the timing.
You may find that strobe timing is not necessary but... If you have strong magnet you could hold a timing disc on to the end of the crank and use a wire pointer held by a casing screw. Again using the rod in the plug hole determine TDC and zero the pointer, then mark the BTDC degrees and away you go. However, the magnet might fly off when the engine is running so perhaps make the TDC and BTDC marks on the crank nut. They will only remain reliable until the nut is ever removed and refitted. With the engine running you should be able to check how accurate your static timing is and carefully adjust the stator to get it exact. It may be a good idea to get someone to hold the throttle or lock it at high revs whilst adjusting the timing. Be careful not to get your sleeve caught in the primary chain or you may end up with spot on timing and a mangled hand.
Dave.
Hi Dave
Thanks for that, it seems to me that when I timed it with the mag working it was spot on, now with the EI I cannot seem to get to where I could with the Mag timing method, I am using the same method apart from not being able to see when the trigger unit is about to fire rather than the points just about to open
I am using a continuity meter on the leads from the trigger unit to the coil, I think I will rig up a light instead to see when it is just about send 12 volts to the coil or maybe something is moving, usually I am pretty good with ignition timing but is seems the Thorspark trigger system is more difficult to set up than a manual system using points
I will having another go later in the week so will update then
Mike
Hi Mike,
I found some info re Thorspark setup. The image appears to show the point at which to set full advance. Does this help?
Dave.
i have just had another thought regarding electronic ignition. i dont know the thoroughspark system but a boyer would retard the spark electronically not manually so a manual mag pinion would be necessary.
Hi,
I have just had a read re Thorspark and it does rely on the standard AAU to advance the spark so the standard method of timing is used. So it looks like the marks on the rotor and stator must line up when the AAU is held at fully advanced. Once set up statically a strobe can be used with marks on the end of the crank nut and a wire pointer. If the stator has been set up with the screw in the middle of the adjusting slot then the stator can be moved to advance or retard the timing using the strobe for accuracy if thought necessary.
Dave.
Hi sorry about the delay getting back to you all and thanks for all the help
I did set up dynamic testing with a strobe light and found I was retarding the ignition rather than advancing it during the manual (Move the trigger unit a bit at a time scenario) so once the marks were set up on the timing disc and the pointer I strobed it and got it close, however the mark on the timing disc did bounce around a lot (I was using a RSM timing disc bolted to the primary drive sprocket) but I thought this is as close as I am going to get
it starts first time and revs up ok I will go for a ride, however not pulling very good, came to a hill had to change down to get up it. dam ignition is still out, back to the lock up! it seems that a fine adjustment on the trigger unit makes a big difference to the timing
I am going in the right direction though,going to the Notts car show Sun /Mon so will be back to advance the ignition a little more when I get back and try again
Mike