The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: bakerlonglegs on 03.05. 2020 14:59
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Hi,
I’m nearly finished - my long running A10 rebuild might actually start soon! However I’m stuck (again!) and seeking advice before doing expensive damage. Please can anyone help with this issue?
The engine has been completely rebuilt by an engine specialist. He said they had used assembly grease during the build and the engine turns over on the kick start. Before starting it I’m keen to circulate oil around the engine but despite turning it over many times on the kicker there is no evidence of oil leaving the oil tank. The rocker covers are off and there is no oil reaching the rocker spindles. I have taken the oil tank off and checked all the external pipes are clear. The oil pump is new (SRM).
Is it normal to be unable to circulate oil just with the kicker? If so, is there anything else I could do to prime the engine with oil before starting it for the first time?
If it’s not normal and I should be able to move oil around with the kicker, are there any suggestions as to what it could be?
Many thanks!
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You can prime the return side of pump by putting 200-300cc of oil in the sump. But that does not show that the the feed side is pumping.
Could be an airlock between tank and oil pump. Happened to me a few times. First slacken the oil feed at the case until oil flows out, then tighten. If not sorted remove timing cover and slacken oil pump fixing and see oil come from the pump/crankcase joint, then retighten and that should sort it.
Some owners sort it by pushing the bike whilst in gear but that is hard work.
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I’ve recently started my engine after a complete rebuild and putting an SRM pump on. SRM advocate slackening the oil pressure relief valve assembly on the front right of the crankcase and kicking the engine over without plugs in until oil appears there. It took a good few kicks for me - somewhere over 50. When the engine finally started it was only 1 or 2 seconds (if that) before I could see a good strong oil return. When it starts running, a finger over the oil return in the tank should prime the flow to the rocker box.
Adrian
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If the oiltank is still off, prime the feedpipe leading from the tank. Kicking the engine over with the plugs out should see the oil happily disappear into the pipe, as the primed pump draws it down. With the PRV removed, oil should appear from the central hole in the crankcase as the engine is kicked over. Feeding oil into this hole with a pressure oilcan will force oil into the oil gallery running around the back of the timing bush, and then to the bush bearing surface and on into the crank and big ends. The anti wet sump valve should prevent back flow to the pump.
If the tank is back on and filled with oil, air pressure on the vent pipe, oil cap on, will pressure feed oil to the pump. A little bit of kicking should see oil at the PRV cavity.
Once the engine is running, it takes a few heart in mouth moments before oil will return to the tank, as this side of the system is effectively empty, but introducing oil into the return pipe before replacing the tank, or if the sump plate is off, pumping oil up the pick up pipe will give the return side of the new pump some initial lubrication. Julian's suggestion is another trick, easiest is via the rear rocker cover.... stick a good amount of oil down here anyway to bathe the camshaft and followers.
Depending on how much oil is in the sump, the oil will either gulp into the tank to start with as air and oil are scavenged, or be a continuous stream. Once things settle the oil stream will vary between a continuous stream at high engine speeds, to a gentle gulp as the pump scavenges air and oil at tickover. Oil to the rocker gear will appear late in the proceedings, being fed by the return from the pump.
Avoid excessive periods at idle speed to start with, modern expensive oils have anti wear additives and this can result in poor ring sealing. Cheap oil is fine for running in.
Swarfy.
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Thank you very much for all the replies and advice, that gives me plenty to try out. Pleased I haven’t broken anything! I’ll report back....
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I've just had this very problem after a complete rebuild. A blob of grease behind my SRM oil pump was the cause of my grief.
Steve
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Thank you very much for all the replies and advice, that gives me plenty to try out. Pleased I haven’t broken anything! I’ll report back....
Kicking didnt do it for me, but taking the plugs out, putting it in gear, and pushing it around (maybe 50m at most?) got the oil returning pretty quickly.
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kiwigf me to with the push, then I gave up fired it up and boom 3 seconds later sorted.
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I have kicked forever before now with and without the PRV out I find the best way is to make sure there is a fair bit of oil in the sump kick it a few times then fire it up for me its never taken more than 2 or 3 seconds for the oil to come spurting out of the return pipe.
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After I fitted a filter, the first start was scary as oil took ages to come through! I now fill the filter canister before screwing it up.
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car type filters really soak it up when you fill one up as I do on cars and my van I walk away do something else and then go back and see it has vanished, then it is repeat the fill until its not running down your arm fitting it *sarcastic*
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There is a school of thought that says as long as the engine was lubed etc on assembly then all the kicking and walking is unnecessary, and the maths seems to bear it out.
Assuming stamina and a strong right leg, fifty consecutive kicks (and that's some going!) turns the engine maybe 100 times, but start the engine and 100 revolutions occurs after 4 seconds at 1500rpm.
No engine is going to seize after 4 seconds even if it was assembled dry.
Better to ensure lube on assembly, check oil is present and will freely flow from the feed pipe etc, the filter (if fitted) is full, and test run the engine all the time watching for the return.
It's worth bearing in mind that the oil will be sloshing all round the engine and doing it's stuff some time before the scavenge side visibly returns it to the tank.
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Agree with Rex somewhat, but without an oil pressure gauge a first start is always a heart-in-mouth situation. Maybe it is pumping oil into the engine, but with a dry sump, it’s gonna be several seconds before there’s a return to tank. And so you sit there, engine running, counting 4, 6, 8 seconds …. should I stop it or is the oil about to appear from the return? Putting oil in the sump to start with proves nothing either – the return of that oil to the tank could give you a false sense of safety when, in fact, all it’s doing is returning what you put in, not what’s being delivered to the engine if the delivery side isn’t working.
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I think I have done the kicking bit once when I was young and fit. As long as the engine was put together reasonably oily, Starting it works for me.
With piston engine aircraft, the wisdom is that you don't hand turn the prop a few times as we used to do to confirm compression an all cylinders. It's reckoned that turning the engine over slowly with no oil pressure caused more wear than just starting it up. You need oil to be flung around the crankcase to get to the cylinders. Another thing is that with a new piston aero engine you don't run it at low power settings or the rings won't bed in.
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I'm a great believer that after an expensive rebuild, anything you can do to ensure lubrication of plain bearings under light load has to be good. For car engines, pressure oilcan on the oil light gallery to prime the crank bearings, replace oil light switch then cranking with the plugs out until the oil light went out was the usual way. The exception was the Ford Pinto engine, where the oil pump could be driven directly with a hex socket on the distributor drive.
Priming the A10 pump is easy, and although the engine builder says everything is oiled up and ready to go, I always think it's a similar phrase to "The cheque's in the post" or worse "Yeah, sludge trap's clear"
If it was mine, I would be making sure all was in order before loading up those big end bearings.
Swarfy.
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You're not loading up any bearings at tick-over speeds and under no load.
What did all the factories do at the end of the production line? Half a gallon of juice, ride off to the loading bay then run back for another one..
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I confirm Swarfcut's method - prime the feed, squirting oil down with an oil can. Do this while turning engine over - until you see it come out of the feed to the removed PRV. This was the one most important thing our engineer said to do, before starting the engine...
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when my mate owned my beezer in 1978 he came to my house with a tin of stp oil treatment [treacle ] and we decided to put it in . I think we stood and watched the oil return hole stop flowing for about 3 minutes, the stuff was that thick the pump had trouble pulling it and pushing it into the engine and we were both a bit concerned about what was happening all the time he was blipping the throttle, and we were looking at each other with that worried look *eek*. he came to my mums funeral today and we had a good laugh about the good old days *lol*
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Hi Berger. Glad to hear the funeral went OK - always a milestone losing one's mum. When you see someone in ill health suffering you know it was best for them and it somehow lessens the loss.
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Good story Berger, I can imagine the looks on your faces as you waited! Sorry to hear of your Mum’s passing, I hope the funeral went as well as it could under the current circumstances.
Thanks again all for your advice!
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Just about to put the old girl back together so this thread was great.
My condolences to you Berger, just had my big brothers funeral yesterday, he lived in Germany and we in England so had to do a video link. His German family did him proud.
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When I rebuilt mine right down to small parts I worried about the same thing. Every day I would kick the bike over without plugs for two or three minutes or until I ran out of puff. I never got a sign of oil. I was unwilling to go squirting too much around as I want the rings to bed it quickly and so didn't squirt any down the plug holes. I planned to tow the bike around the block but in the end I gave it a kick in the shed and it fired up straight away. The oil was through in about 15 seconds and so all was sweet. My feeling is that if you don't get a scavenge feed in 15-20 seconds turn it off and try plan B but in that time you aren't likely to do any damage.
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Hi All
I always use this method to get the oil circulating after a rebuild. Leave the plugs out put the bike in second gear and take it for a walk around the block to get the oil circulating, always worked for me. One time a neighbor said will it not start, I replied no. Will you have to get the dealer to come out to it under warranty.I said the warranty had run out in 1961 as he walked away red faced.
ELLIS
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Hi Everybody,
This is a good topic. Soon I will have to fire up a newly re-built A7. Has anybody tried using a new grease gun filled with oil and connected to the oil inlet? Initially leave the sump plate off and pump away until oil drips out of everywhere. I'm too old to try 50 kick starts or pushing the bike 50 metres!
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build the engine with lubrication and a full crank gallery, squirt oil into the feed on the crank case. make sure you have oil down the pipe to the crank case, start it up , if oil isn't returning in 5 minutes your in the shit *eek* but if everything is working correctly it only takes a matter of seconds.
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If you have replaced the cam and/or followers you should not turn the engine over a zillion times. Fill every oilway and crank during assembly, fill half a litre in the cases to make the crank sling around the oil. This will lube the pistons and cam for a while until oil exits the bigends. The cam needs a proper break-in so no put-put idling but 2500 revs at least. This will generate the needed oil-wedge which separates the surfaces and reduces the micro-welding happening on new, unrun surfaces of the lobes/followers. As this process is done within the first ten minutes I would ride the bike around the block several times. Hard accelerating gives the rings a chance to bed in instantly. After those ten minutes you will not have ruined anything but done a lot for a long lasting engine. I have an A65 engine here from a bike which did not run properly - 65 mph maximum! Recently rebuilt engine from a high-nosed shop. I found the powerloss - cam lobes are all worn down to between 4,2 and 4,9mm valve lift. The thing was probably assembled dry, took ages to get oil circulating while the engine idled and thus all the damage that followed in those lousy 3000kms that the bike was "run-in" was started on the first kickstart of the new motor...
cheers, Harty
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I always use "Penrite cam & bearing assembly lube" ( on cams & plain bearings) never had a problem.
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On my 650 of another popular marque, it’s easy to see that the oil pump is pumping oil towards the crankshaft, by removing the pressure relief valve and turning the engine over a couple of times. Or you can do it before fitting the timing cover. Does that work on a BSA?
That’s all you need to know, to avoid running without oil circulation. You take a look at any oil pressure indicator, light, or gauge, obviously.
Kicking the engine over 500 times, while looking into the oil tank filler is just a bad joke, as far as I’m concerned.
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wears your valuable kickstart mechanism too *bright idea* 500 starts less
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I while back I started priming the oil system by spinning the pump using a cordless electric drill as my right hip complains if I do too much kick starting. You need to have a motor with the tacho drive prongs at the end of the pump drive gear and the task needs to be done at the right stage in an engine assembly job. You have to take off the worm drive gear before this. Removing and replacing needs abit of care as you have to rotate the crank while unscrewing the gear, so it's easiest done when the barrels are off. I made a little thing to fit over the drive prongs out of an old 1/4 inch drive socket (Chinese variety) that I cross-drilled to accept a little peg that can fit down the slot between the prongs. The photo shows it in use on my A65. This bike has an oil pressure gauge and it registers pressure after only a few seconds with the drill. That way the sludge trap gets filled ok and you can check the return side too.
HTH,
Jon
(http://)
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I would be concerned that the tangs of the tacho drive would break with this method, they are brittle.
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Agree, I doubt the factory faffed about.
I use plenty of oil during assembly then fill thru the rocker box which ought to drown everything but not too much in the tank..a few kicks to move it around the pump, fit the plugs and fingers crossed.....always find oil back in the tank after a few seconds, and even if it takes a while its no detriment with the amount of oil that's sloshing around anyway if you've given it a good fill up.The Penrite lube sounds like a good idea though.