The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Chrisf1 on 11.05. 2009 11:26

Title: wet sumping
Post by: Chrisf1 on 11.05. 2009 11:26
Hi again everyone can anyone tell me how much oil I should expect to find in my crankcases after a day standing. I usually leave my baby with the sump plug out and a jug to catch oil and replace and top up before use I took it out for a 30 mile spin yesterday first run since complete oil change and fitting a hide hi filter and never took the plug out untill today when I took it out 1/2 pint straight away is this normal or excessive also I still seem to blowing out the breather while using as it is getting on my highly polished rear ally rim and gathering around the centre stand area while standing after use this engine has only done 275 miles since total rebuild so still running in opinions please thanks Chris
Title: Re: wet sumping
Post by: dpaddock on 11.05. 2009 20:55
Beautiful SR, Chris!

The sump holds about 135 ml of oil (about 5/8 pint); any more than this after shutdown indicates the oil pump is not well sealed on its feed side or, perhaps, oil is syphoning from your "hide hi filter".

As for breather barf, much has been written here and in other places. It's caused by excessive blowby and/or a breather circuit that is plugged or otherwise in need of attention. After all is said and otherwise done, most A10 breather victims simply vent the rear rocker cover via an automotive PCV valve to a catch bottle.

Title: Re: wet sumping
Post by: Chrisf1 on 12.05. 2009 14:33
Hi David thanks for your reply and compliment as I am only showing 1/2 a pint I will take that as correct I have been told on another forum that the blowback is probably caused by the new rings having not settled into the re-sleeved cylinders yet as the mileage is so low I hope that is also the cause cause of the oil collecting while standing as it does stop after standing and running down whatever it has clung to but it looks ghastly and embarrassing when I pull up anywhere thanks again Chris
Title: Re: wet sumping
Post by: A10Boy on 12.05. 2009 20:00
I would fit one of these that should stop it sumping.|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A1|294%3A50 (|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A1|294%3A50)

Title: Re: wet sumping
Post by: Chrisf1 on 12.05. 2009 20:33
Hi Andy They frighten me Chris
Title: Re: wet sumping
Post by: bsa-bill on 12.05. 2009 21:24
Well the worst that can happen is it sticks and stops oil returning to the tank - this you would soon know about as the sump fills up.
On the other hand there are three such devices in your engine put there by BSA, two of them could cause a lot more damage than one in the return line and yet you probably never give them a thought.
Now what really would frighten me is the guys that fit a tap on the feed line !!!! even coupled to a kill switch it's an accident waiting to happen.

All the best - Bill
Title: Re: wet sumping
Post by: groily on 12.05. 2009 22:18
Oh I don't know Bill - there be beasts that need something to stop the entire contents of the tank heading straight for the crankcase! Nortons, AMC twins (my weakness), etc. A mag earth diverted to a tap works fine as long as sod's law doesn't intervene. I'm inured to the problems and have several inline feed taps. Despite warnings of the perils, so far so good . . . fingers crossed . . .. It's all a question of doing the pre-flight checks  . . . fuel on, oil on, ignition cut-out off, FIRE! Keep looking for non-existent taps on my BSAs (good discipline!) . . . and I find them not . . .
But boy, are the consequences of early Alzheimer's dire . . .
Title: Re: wet sumping
Post by: trevinoz on 12.05. 2009 22:20
Andy, don't fit one of those "things". I have seen the results of one not operating. Not pretty!
Title: Re: wet sumping
Post by: rocket man on 12.05. 2009 22:48
dont do it mate get an srm sump plate kit
then all you have to do before taking your bike out is remove the
drain plug collect the oil in a clean container and put it back in oil tank
job done dont fit a valve its not worth the hassel if something goes wrong with it
Title: Re: wet sumping
Post by: Chrisf1 on 13.05. 2009 09:34
Hi rocket man that is exactly what I do the wet sumping doesnt really bother me as much as the drip which must be coming from the crankcase breather by the mag but hopefuly that will settle with a few more miles on the clock Chris
Title: Re: wet sumping
Post by: Chrisf1 on 13.05. 2009 12:59
Hi again Bill your suggestion of the anti wet sumping valve has perturbed me a little I was under the impression they fitted in the feed from the tank that is why they frighten me, am I wrong and if I am I may well take action on your suggestion can anyone confirm thanks Chris
Title: Re: wet sumping
Post by: A10Boy on 13.05. 2009 13:56
Well that opened the proverbial can of worms !!!

It says in the words that it goes in the feed. I should say that I have never used one, never had problems with wet sumping, but i dont see it as any more or a risk than the failure of the PRV. Although if you add a valve you also add the risk of failure however small the risk is.

Having said that, a good oil pump shouldn't wet sump.
Title: Re: wet sumping
Post by: Chrisf1 on 13.05. 2009 16:18
Hi A10 boy I agree with what you say but every BSA forum including this one I have ever particpated in on-line has a horror story caused by no feed to the pump from one of these valves so I would be very suspect of its reliabilty in such a critical place. But I was wondering if you meant fit it in the return line because of Dave's suggestion earlier that it might be syphoning back from my hide-hi oil filter which is mounted vertically behind the tool box but I am convinced that it has a non return valve as instructions say it can be mounted horizontally or vertically. Chris
Title: Re: wet sumping
Post by: bsa-bill on 13.05. 2009 18:29
IT goes in the return line - ask Bri-Tie who sell them.
I totally agree with you all if it was meant to go in the feed

Similar thing with filters - put them in the return, sure cars (by no means all of them) have them in the feed but they are bypass filters with an escape route for oil should they block.

I have a non return valve fitted in the A10 return - been there for ten years or so without problem

I wonder how many of the  scare stories are actual and how many if any occured with valves fitted in the feed.

All the best - Bill
Title: Re: wet sumping
Post by: Chrisf1 on 13.05. 2009 20:29
Well Bill forgive me if I am wrong how would being in the return stop the wet sumping the return is at the top of the oil tank and above the oil level so how is oil going to run down it and how does wet sumping lower the oil level in the tank Chris
Title: Re: wet sumping
Post by: bsa-bill on 13.05. 2009 21:10
Oops you got me.
I'm mixing up filters and anti sumping valves.
And they do indeed go in the feed line. please disregard my ramblings - I do have one more pill to take

Al the best - Bill *red* *doh* *dunno2*
Title: Re: wet sumping
Post by: Chrisf1 on 13.05. 2009 21:13
Well played Bill i've made worse one's than that Chris