Author Topic: Wet sumping  (Read 2231 times)

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Re: Wet sumping
« Reply #60 on: 28.06. 2019 23:10 »

 I forgot to add my rubles worth to the ball seat when I saw the missing flange; and Lees suggestion came first to mind to clean it up before doing the ball tap method (I was thinking it's Musko's ?), but Johns' idea is probably best
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline Swarfcut

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Re: Wet sumping
« Reply #61 on: 29.06. 2019 10:08 »
Just checked on a handy timing side case and my bush is the same as pictured, with the bearing metal not reaching the inner face of the carrier. The steel carrier flange bears directly against the crank web, poor engineering but cost effective for BSA.

 Original white metal in steel carrier bushes were the same, steel to steel crank to bush contact. The reaction of the oil pump drive sleeve and crank pump worm tend to push the crank towards the drive side, so in theory this junction is lightly loaded, in contrast to the A65 design in which  the oil pump reaction draws the crank the other way, towards the bush, hence the use of a thrust washer here to control float on later models, 1966 on.

 Your bush looks OK.

 Swarfy.

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Re: Wet sumping
« Reply #62 on: 29.06. 2019 10:23 »

 
Quote
......Original white metal in steel carrier bushes were the same, steel to steel crank to bush contact. The reaction of the oil pump drive sleeve and crank pump worm tend to push the crank towards the drive side, so in theory this junction is lightly loaded, in contrast to the A65 design in which  the oil pump reaction draws the crank the other way, towards the bush, hence the use of a thrust washer here to control float.

 So Swarfo- are you saying the egg came before the chook?  *conf2*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline Swarfcut

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Re: Wet sumping
« Reply #63 on: 29.06. 2019 10:50 »
Yes, No, Maybe.... The A65 thrust washer appears a later addition, when the ball race drive side main was changed to the conventional roller type, and side thrust towards the bush was taken by the the washer being loaded against the bush face.
 The shim pack is still necessary at the main bearing crank end on initial set up to give the correct float, and accommodate variations in crank and cases, rather than having varying thickness thrust washers as in usual automotive practice.

 With a single piece bronze bush the conundrum is easily solved, but this would have cost too much for the bean counters, until failure rates and warranty claims made an upgrade to a one piece solid bronze bush essential. So to use this type of solid bush, rather than a composite steel sleeved type as pictured, is a good idea, giving a better chance of preserving the crank face by having a much better bearing surface, and going some way to keeping the initially set endfloat correct over time. A further advantage is that the bush can be line bored to give a running clearance to a crank ground to a dimension which just cleans up the journal, not a set undersize, enabling an otherwise unserviceable crank a new lease of life.

 Swarfy

 Additional. I posted the thrust washer controlled the float, not strictly true in that it simply maintains a running clearance. The shim pack sets the amount of float.

Offline Colsbeeza

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Re: Wet sumping
« Reply #64 on: 01.07. 2019 12:10 »
Thanks for the replies and suggestions. I think Swarfy is correct. I purchased the T/S bush about 25 years ago from C & D if memory serves me right.  It is a composite steel backed item. The bronze?? clears the inside surface of the steel carrier by about 1/2 - 1mm, but I haven't measured it.
Also the steel carrier appeared to be scored, but not the case. It has only 80 miles on it sofar, so no real damage I hope. Oil pressure has been 60psi cold and 40psi hot. The carrier surface feels quite smooth. I haven't cleaned it yet, just scraped off the gasket material sofar. However, before dismantling the crankcase, I could not get any end float, so suspect there may have been a bit of pressure between the carrier and crank.
The photo was a bit too close up, so I have attached more distant ones. The scoring doesn't look so much. From 20 feet away, there is none at all. *roll*
I did think that it had a white metal liner, but it appears to be bronze. Failures were I think related to the inadequate pinning of the liner to the carrier.
As mine is well lined up and about 1.5 thou clearance between crank and bush, I will leave well alone and hope it holds.
Now back to the ball and spring, thanks John O'R for bringing that to my attention. I knew about it but hadn't considered it. But now rethinking, I am leaning towards doing what you suggest. John  I do remember somewhere seeing a diagram of someone's modification, which suggested an additional diagonal oilway as there was some concern about the distance the oil had to travel past the ball before entering the bush. BSA - Bills website perhaps?? I will try to find it.
I haven't contacted SRM yet, but presumably they may also supply the extended plug.?? If not your dimensions will help me out.
Tomorrow, I will measure the dimensions of the passage depths and post them. My motor is very original, having been off the road since about 1975, so hopefully no-one has meddled with it.
Cheers
Colin
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Offline Colsbeeza

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Re: Wet sumping
« Reply #65 on: 01.07. 2019 12:12 »
Damn lost two of the pictures. Here goes again.
Col
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Offline Swarfcut

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Re: Wet sumping
« Reply #66 on: 01.07. 2019 13:14 »
Col.. From experience all those bits look pretty good for a careful rebuild and use as is. 40 PSI Hot would say its a good motor.

  The other alternative to the ball valve problem is to remove it completely, just resealing the plug back into the case. This removes any resistance to oil flow by the ball and spring.

 How you stop wet sumping on standing with the valve removed is with an aftermarket  valve in the feed from the tank. Spring loaded, simple, effective, but a disaster if it fails to open under suction, and generally not in favour.  Alternatively a simple on/off tap, easy, cheap, but not recommended unless  it has a 100% foolproof way to prevent starting when it is turned off. Plenty of threads on this Forum, so all the information and the pros & cons of each, plus A65 type ball valve conversion are well represented.

 BSA Bill's system was a poor man's timing side conversion, but even so very cleverly executed without the costs of other well known modifications.

 At the end of the day when you consider the amount of use the bike will get, just cleaning up the ball seat and  a drain plug  type sump plate  could be by far the most cost effective option. Don't worry about the small offset in the seat, provided the seat is reasonable, the ball will roll under the spring pressure and seal OK.

 Swarfy.

Offline Colsbeeza

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Re: Wet sumping
« Reply #67 on: 01.07. 2019 14:01 »
Thanks Swarfy,
Yes it was on  Beeza Bills website.   https://cybermotorcycle.com/archives/bsa-a10/mybsaa10rollerconversion.htm
I don't intend to go down the risky path of a valve in the feed line. At my age, forgetfulness cannot be too far away.
As it has not been wet sumping, my guess is that my oil pump clearances are pretty good. I had stripped and re-assembled it carefully last year - spent hours on it.! I have been using Penrite 20-60 oil with no friction modifiers, so thin enough to test the leakage.
I have sent an email to SRM to see if Gary can supply a new grub screw, (spring and ball he can). If not I can make one. I am hoping that this stripdown will by my last, so I won't rush into it yet.
I have fitted a sump plate with drain plug, so I can cope with some wet sumping if it develops.
Sitting on the fence is one of my lesser qualities - I prefer to say thorough .*dunno*
And GB - sorry I think it was RichardL who glues a ball on a tube to lap the seat.?
Col
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Re: Wet sumping
« Reply #68 on: 01.07. 2019 14:17 »

 All I can say now is that first photo you posted is very deceptive (or my eyes) *conf2*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online orabanda

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Re: Wet sumping
« Reply #69 on: 02.07. 2019 00:25 »
Col,
Whenever I have crankcases apart I fit the A65 spring in place of the anemic (token gesture) original A10 spring. I also make a retaining screw that is longer (an additional two threads engagement in the crankcase), but rebated 0.100"(spot faced using an end mill) so that the spring will sit central on the plug.

There is no obstruction to the oil flow by the ball with the A10 system, but the spring pressure is pathetic (*** weak!).

The extra threads on the longer (3/8"BSW) plug provide peace of mind that delivery oil won't escape (leak) into the crankcase. Use 569 loctite (hydraulic sealant) on the thread when installing.

When installed, pushing on the ball from the oil pump face with a punch will show that the ball seating pressure is much greater (strong).

attached pics compare the A10 spring & retaining plug to the A65 spring, and the longer (spotfaced) plug I make. The A65 spring is the longer one.

Cleaning is easy if required; remove oil pump, depress ball with punch, and lightly blow,

I prefer this to copying  the A65 where the supply oil has to find its way between the ball and the oil gallery.

Richard


Offline Colsbeeza

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Re: Wet sumping
« Reply #70 on: 02.07. 2019 12:47 »
That looks good Richard.
Can I presume that like John O'R, the main passage is drilled out over its full length to 5/16" (If I understand John correctly), and you then cut a 3/8" W Thread for the plug.?
I had also pondered that the back end of the spring may wander a bit due to the large diameter of the plug, but you have addressed that. I had thought of having a pointed plug to locate the spring, but it would be difficult to locate it properly when pushing in the spring from the oil pump side.
I would imagine that the passage diameter is critical to ensure oil flows around the ball with no flow restriction.
Your last line has confused me - Doesn't the oil still have to find its way between the ball and the oil gallery.? Don't you end up with the same design as the A65?
Dutch, yes I hadn't looked closely at that photo and it surprised me that it looked bad.
Col
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Re: Wet sumping
« Reply #71 on: 02.07. 2019 13:09 »
Hi Col,
My apologies re the plug thread size; not drilled out (increased) - use the standard BSW size. It must be 5/16" (memory failing!).
The difference to the A65 is that once the spring is fully compressed the ball has moved below the hole supplying oil to the crank (in the side of the crankcase).
You can confirm this during trial assembly. Check depth of spring compression using depth gauge / vernier.

The spring resistance (back pressure) is the same as an A65.

Richard

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Re: Wet sumping
« Reply #72 on: 03.07. 2019 09:26 »
Richard, Are you suggesting keeping the basic layout the same, but just fitting a stronger A65 spring, as your experience proves this will help with no detriment to the oil supply to the bush?
 Swarfy.

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Re: Wet sumping
« Reply #73 on: 03.07. 2019 11:05 »
Swarfy,
That's correct; works a treat.
Richard

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Re: Wet sumping
« Reply #74 on: 03.07. 2019 13:38 »
Hi All
Richard,
I have not seen a strong(er) spring for an A65 as in your photo
SRM list the same spring for A10 and A65   *????* *????*

http://www.shop.srmclassicbikes.com/product/oil-pump-spring-a50-a65-a10-anti-drain-valve

Just wondering???
John
1961 Super Rocket
1963 RGS (ongoing)