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primairy chain overoiling

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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Wed Apr 12, 2000 12:50 pm

primairy chain overoiling

37 knuckle :even when i completely turn in the adjustment screw on the oilpump quite a lot of oil is coming through the primairy chainoiler/breatherpipe.i lost a quart in maybe 30 miles!could it be the breathervalve or its housing?
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Cotten

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Joined: Thu Sep 30, 1999 12:01 am

Location: Central Illinois, USA

Post Wed Apr 12, 2000 2:00 pm

Anything is possible, like the breather gear bore had been severely scored, but what might be more likely is that you were merely purging sumped oil from sitting. Does the machine see regular duty and still do this, or did it just start pukeing after being idle over the winter? (I see from your post on another thread that you are hip to this problem, so my next question would be; Have you updated to a later pinion shaft/pump drive? Using a '55-'57 shaft allows some blow-by from the crankcase and can overfill the camchest I am told, although I use them in both of my '37 ohv's without grief.)

[This message has been edited by Cotten (edited 12 April 2000).]
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Wed Apr 12, 2000 3:52 pm

no,these are its first miles on the road after restoring.I had to rebush the breathervalvechamber,a piece was broken out , and i put a later pump on with the larger supplygears(1940),same type of pump with the oiladjust screw under45degr.angle.The pinionshaft is the one piece type,with the drivegear as on a 1940 knuck.I checked the oilreturnflow in the tank,and compared to my 74 knuck its some less. looking at the breatherpipe on idle i can see the the oil gathering,but it s not really dripping off. I wonder howmuch is supposed to come out of that pipe,and in what time.I cannot see it on my 74,cause i have that lefthand sidecar over there.When i drained the crankcase this morning,after riding yesterday, oil in the order of half a glass of beer came out.that same amount was in my primarychainhousing when i took it off .How much would be the effect of small longidudinal scores in the breatherhousing (,due to handreaming)be on the total?
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Cotten

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Joined: Thu Sep 30, 1999 12:01 am

Location: Central Illinois, USA

Post Thu Apr 13, 2000 2:06 pm

After 10 miles or so your system should have purged any sumped surplus, and only a mist should be coming out of the breather. I would not think that length-wise scoring would affect much. Usually only annular grooves made from objects coming out of the gallery holes will have any effect at all, usually in that it messes with the suck/feed timing, and that makes for messy upper ends, not breather blow-by. If we assume that your repair did not change the window location very much (most will put a degree wheel on them and carve out to square), I would then look for an extraneous cause: I had a pan rebuild that would sump full overnight no matter how I burnished the ball check. I yanked the whole pump, and just by chance while using compressed air to purge the oil I found that someone had drilled the camcover feed gallery internally in the right case to connect the feedhole on the pump deck. This bypassed the ball check completely. (A pox on the bastard who did it!) Anyway, a little set-screw plug put everything right. If your breather gear is on the right tooth, I would trace your oiling system to be certain that all is compatible. I also assume that your chain oiler needle goes all of the way to a point, it's seat is not damaged, and the ball check seat has not been cracked by being "set" with a punch. Even over-filling your oil tank above the camchest breather line could affect how much the breather gear must separate by centrifugal force. Do you have a baffled breather gear or a screened one? Let us know what you find!
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Thu Apr 13, 2000 4:25 pm

this morning again i found a half glass of oil in my case!this convinced me direction wetsumping..,the same time i thought:lets put a 37 pump on with the smaller supplygear(and is original for this bike),yet i wasn t sure.It brings in less oil thus makes it easier to pump the amount out So I took off the pump,in order to inspect and grind the checkballseat and maybe to put on that other one when i noticed that the supplygearkey made an incesment in the pumphousing of about 3/32,same with the returngearkey!They didn t connect with each other..How on earth did that happen,i had been carefull enough,must have been my weak sight when i inspected!!that was #1.this decided me to put on the 37 pump. i also saw another thing on that 41 pump:#2 i knew the governor was taken out of the cover,and the holes welded,to have the original look,and have more oil going to the bigend and heads(long story)that looked ok !,but i noticed that in the inbetween plate the hole for the governordrive was not closed off(that was a real mistake i quess),and that the oilreturn drivegear made a small cavity in the plate.(???) Conclusion/solution:I grinded the checkballseat of that 37 pump and put it on,lacking an original cover i temporarely used a panheadcover(alu)that comes close to the orinal 37 set-up.
I had to take off the camcover to prevent the key dropping, and now i only have to start...Thanks cotten for your clear story,the breatherbushing has the same hole location as original,and so is the timing. your suspect of the setscrew not bottoming was also correct,i solved this earlier by turning off a small piece of the screwhead, so it comes deeper.I am not sure what you mean by that baffled gear however,i have a screen in it,and it is original knuckle with the casted end.
I will keep you informed when i have started it,really hope thats the end of the story !first i have to filter all that drained oil through a nylon stocking...
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Thu Apr 13, 2000 7:14 pm

started engine,pump functions ok/oil returns/pressurises. To my opinion still breathing too much oil however,completely closed off the needle valve,takes about 30 sec.on idle to cover my finger with oil if kept against bottom of breatherpipe,have to watch that chain damned well!!!.Is not really blowing a lot of air out.Reminds me of a shovel that had oil coming out of its breatherpipe,when the plastic breather was replaced it stopped!? breathervalve?but not throwing out oil at rockercovers!!
How misty is that exhausted mist supposed to be,what amount of oil are we speaking about?Maybe its all normal(wishfull thinking)
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Cotten

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Joined: Thu Sep 30, 1999 12:01 am

Location: Central Illinois, USA

Post Fri Apr 14, 2000 4:27 am

Rein! (I burnish ball checks after grinding them, but that's another thread; and retiring the panhead-ized pump should at least keep your tins from leaking on the interstate.) Yeah,... you have too much oil coming out. I would be picking at straws to guess what is going on. When you swapped pumps, you did have different bypass springs, right? I'm really reaching here, but do you have an aftermarket cam? (No! Not Andrews!) or perhaps I can ask (forgive me if I am being profane)if you are running an oil cooler and/or filter? From what I have learned about Indians lately I might even ask if you are running 'Total-Seal' rings. Your '37 pump is actually turning faster than designed because of your later pinion setup, but that should only be an improvement. Could it be that your pinion update did not properly align the oil feed holes, and all of the volume intended to feed your crank is instead going out the relief hole and flooding the cam chest? More possible causes might wake me up later...
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Fri Apr 14, 2000 7:13 am

cotten,the cam is orig.,and the pinion holes line out correct..
I know that the function of the breathervalve besides of letting air out on downstroke sucking on the rockercovers is, but besides that it also sucks out the oil from the trap,under it,am i wrong?
this would mean that a not perfekt fitting breather valve,maybe at a certain spot,is not sucking out that amount,thus creating the problem? Next thing,i made the oilpumpcovergasket on this new 37 pump myself, myself,maybe if its too thick it lets returnoil pass by.I couldn t really notice more oil flowing back in the oiltank,it comes out in,sort of, an intermittent flow(is that word correct)I am going to check the level in my crankcase now, thanks sofar
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Sat Apr 15, 2000 6:41 pm

after draining the crankcase i had the plug out for 24 hrs, and nearly no oil came out.
The checkball works fine i guess,it must be the oilreturncapacity why too much oil stays in the engine.Next thing to do is replacing that(thick ?) gasket between the cover and the housing,by decreasing its thickness it must help the gears doing their job,. continuing story of....
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dotman

Posts: 582

Joined: Fri Oct 01, 1999 12:01 am

Location: meridian, id. usa

Post Sat Apr 15, 2000 6:44 pm

have u checked to make sure the return lines are clear as well as the passage ways for return oil?
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Sat Apr 15, 2000 10:56 pm

i just checked that,took off the returnline,and because 37 has a banjoboltconn. to the oiltank ,i checked that bolt! but (unfortunately) it is ok,it has 3 holes and their surfaces equals the pipesurface,so no restriction.thinking about what would happen if the pipe would be narrower at a certain point,because of the pump is supposed to be a positive displacement type,the outstream would be increased like squeezing a gardenhose at the end. Instead of that the oil comes out slowly. tomorrow i go on!!(Its midnight) thanks


back again!that question of dotman woke me up,and what i say now seems in conflict with what i said before!
I only checked that banjobolt..it has the 3 holes and a galley of 1.2 mm deep by 7mm wide to feed the holes.Seems ok, but now the eyelet that is soldered on the pipe(repop!)... it has nogalley,its plain inside!
the oil comes thru a pipe of 45mm2,narrows to 2times 8.4mm2=16.8mm2 and then widens again to about 40+ mm2.
the eyelet restricts by factor 3.
Can someone look in an original banjo eyelet if there is a cavity along the inside(how deep),probably of the same shape of the outside.. I think i am close to the solution,thanks

[This message has been edited by rein (edited 16 April 2000).]
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dotman

Posts: 582

Joined: Fri Oct 01, 1999 12:01 am

Location: meridian, id. usa

Post Wed Apr 19, 2000 6:34 pm

all the banjo fittings i have , have an area cut out inside diameter of the fitting approx 1/16" deep completely around centered on the hole passage and the bolts also have an area cut out around the diameter
centered on the oil passage as wide as the hole about 1/16"
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rein

Posts: 109

Joined: Thu Mar 09, 2000 1:01 am

Location: holland

Post Wed Apr 19, 2000 7:20 pm

thanks dotman,

i made a channel in that banjofitting yesterday of about the size you indicate.(these repop people make fast money that way, why don t they make it right the first time!!) This should eliminate that restriction,made a new tighter bushing for that breather ,made a slimmer gasket for the pumpcover,checked if the camcover was straight...had the engine run,same again!!
Took off camcover,saw oillevel in oiltrap was low,but near pumpsuctionhole was filled with oil.
Today i brought it on the road,had a hose with a bottle connected to the breatheropening, after 10miles a fifteenth of a quart was in the bottle,that makes150 miles with a quart, just for the chain!

Think about bringing in a screen in
the camcover in order to retain that oil in the camchest.


A friend of mine told me it could go over during braking in the engine, i hope he doesn t mean because all my oil is gone!(maybe there is some truth in his words)

I will let you know when everything works out fine,(gets a bit boring maybe!!) in the mean time bring in suggestions please!
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dotman

Posts: 582

Joined: Fri Oct 01, 1999 12:01 am

Location: meridian, id. usa

Post Thu Apr 20, 2000 4:24 pm

sounds like the return scavange section of the pump isnt actually working. Or the feed side (like the key is sheared)
breather isnt set right oil return lines on the heads are plugged or cork gaskets in the push rod covers not sealing. or last but not least the adjusting screws are set to high

since the pump its self is a positive displacement pump what ever is in it is going to be pushed out it has to go somewhere. and if your timing is off or one of those lines is plugged up in the rocker covers then that oil is gonna accumulate somewhere else ie the cam galley which leads to other places or the chain olier tube etc etc etc

the chain oiler screw setting is 1 (one) full turn off the seat spaced with flat washers.
rear chaion oiler if you got one is 1/2 turn open or completely closed.

do you use the original type rocker arm shafts with the slot or the later style with the holes and cutaway area , the slotted ones had to be set just right in the rockers to provide passage for the oil. which was the big shop dope picture with the arrows on the nuts showing left for less and right for more or something to that effect.

I would venture that (1) a line is plugged
(2) rocker arms are the old style slotted type set out of line
(3) loose push rod cover gaskets springs collapsed?
(4) breather timer set wrong
(5) gear shaft key sheared off
(6) a return galley in the case or galley cover is or has been blocked off or is plugged with some crap.
ONE last thing the seat in the chain oil adjusting screw hole is OK? and hasnt been drilled out buy prior racer go fast guy who needed lots of pri chain oil?
break in period oil useage with new rings and valves might cause usage lose of 3/4 to 1 qt in 500 miles but not accumlations in the lower end , after break in a qt in 1000 miles would be about right unless you have case leakage due to bad seal between case halves or bad gasket seals elswhere etc etc etc
hope this heps

ONE LAST THING: if you will notice the feed side gears and the scavange side gears are aboot the same size sooooo whatever is being pushed into the motor must therefore be pushed back out in approx the same volumn dont know the math on how to figure what that volumn should be but any liquid is only compressable by its ability to squeeze into an area, so the diameter of the feed gears X the number (?) times the area of the pump that they fit into should get the volumn of oil pushed thru at any given rpm (?)

[This message has been edited by dotman (edited 20 April 2000).]

[This message has been edited by dotman (edited 20 April 2000).]

[This message has been edited by dotman (edited 20 April 2000).]

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