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Partanen wrote:
I would say the spiral is only to lubricate shaft itself. I'm not sure it could lubricate oil pump gear cog. If it does then some gear oil would be mixed to 2 stroke oil.

When opened this there was red vaseline. Same staff what I found from clutch release mechanism.
I would guess the "red vaseline" was put there by the same person who misassembled the pump and caused the suspected damage to the gear. I have over 30,000 km on my pump, have done exactly what the manual says to do about lubricating the gear (nothing) and the autolube is just fine.

But feel free to do whatever you want, as it's your scooter, and it seems important for you to disagree with how the Piaggio engineers designed it.
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You're right, I'm not very convinced of the engineers skills at the moment.
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Partanen wrote:
I would say the spiral is only to lubricate shaft itself. I'm not sure it could lubricate oil pump gear cog. If it does then some gear oil would be mixed to 2 stroke oil.
I am not going to argue with you, but I am 99% certain the oil pump gear cog is designed to be lubricated by 4T oil from the gear box. The shaft of the oil pump gear is the only part that actually comes in contact with 2T oil. 2T oil never touches the gear itself, at least it's not designed to. At no point does 4T oil come in contact w/ 2T oil.
Partanen wrote:
When opened this there was red vaseline. Same staff what I found from clutch release mechanism.
It's possible the red goop you found was actually gumming up the oil passage and preventing the gear from receiving the 4T oil it needs to function properly.

We spent some time studying the engineering behind Vespa's autolube system because we wanted to make sure it was working as it should on our bike. Do what you think is best for your bike.

Best of luck.
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Aviator47 wrote:
I have over 30,000 km on my pump, have done exactly what the manual says to do about lubricating the gear (nothing) and the autolube is just fine.
20,500+ miles on ours, and like you, no problems. I'd say it's a very durable and reliable system if assembled and installed properly in the first instance.
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SoCalGuy wrote:
Aviator47 wrote:
I have over 30,000 km on my pump, have done exactly what the manual says to do about lubricating the gear (nothing) and the autolube is just fine.
20,500+ miles on ours, and like you, no problems. I'd say it's a very durable and reliable system if assembled and installed properly in the first instance.
Said it before and will say it again:

A significant majority of the "maintenance" on a shifty Vespa is pure and simple voluntary tinkering. A significant portion of the remaining "maintenance" is as a direct result of that voluntary tinkering.
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"Warning! Your Karma Is Negative"

Thanks for that who ever it was. Please send me PM if something is bothering and let's talk about what we could do for it. Instead giving me negative karma.

Is this a matter of language barrier or what?
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Hello

Could the vaseline be degraded 2t oil?

Grumpy
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That was my first thought. But now when I look at the parts I still cannot see what lubricates top of the gear if not vaseline. I can see the canal between oil pump gear housing and transmission, but I think it's a breather canal.
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@ grumpy

with 4 strokes, if you mix synthetic with mineral you get a gummy residue, which is fine if it doesnt sit for years because of the pressures caused by the oil pump.
On my triumphs its something like 40psi, more than enough to push fresh gummed oil out of the way.

Im not sure if 2 stroke oil behaves the same way or not if you mix synthetic with mineral, but i doubt youd get much pressure out of that little pump, especially if it sat for some time.
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TrumpyScooter wrote:
@ grumpy

with 4 strokes, if you mix synthetic with mineral you get a gummy residue, which is fine if it doesnt sit for years because of the pressures caused by the oil pump.
On my triumphs its something like 40psi, more than enough to push fresh gummed oil out of the way.

Im not sure if 2 stroke oil behaves the same way or not if you mix synthetic with mineral, but i doubt youd get much pressure out of that little pump, especially if it sat for some time.
The risk in mixing certain synthetics oils with certain mineral oils is possible loss of additive functionality, not "sludge". This is due to the difference in the additive package chemistry used in the two types of oil. Thus, the mixture may lose it's detergent, acid neutralization or anti-foaming characteristics, which are as much a critical function of the oil as lubricating. This is a very low risk, and pertains primarily to "specialty" oils, such as turbine oil.

Polyalkylene glycol synthetic base stock does not readily mix with mineral oil, and this mix can result in sludge, but polyalkylene glycol is not used in automotive oils.

Much of the Old Wives Tales about mixing synthetic and mineral base oils comes from confusion when synthetics first hit the market in the 1970s, and oil vendors falsely alluded to not mixing the two. Watch this Mobil Oil video about "Myths". At 3:00 is myth #5, where the Mobil Oil Tech Rep states, "Synthetics are fully compatible with conventional oil".

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Hello

The reason i asked was about 10 years ago there was a 2t oil thar was red, because it smelt of strawberries.


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Aviator47 wrote:
"Synthetics are fully compatible with conventional oil".

Roger that. Thanks Aviator for spending the time to clear that myth up for me.

Would his "vaseline" been oil that may have sat in cold and hot conditions?

As mentioned i have seen semi gelatinous oil in old bikes and attributed it to incompatible mixes, clearly this is not the case. In that case also mixing the red and blue oil together would probably not cause this to happen either?
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TrumpyScooter wrote:
Aviator47 wrote:
"Synthetics are fully compatible with conventional oil".

Roger that. Thanks Aviator for spending the time to clear that myth up for me.

Would his "vaseline" been oil that may have sat in cold and hot conditions?

As mentioned i have seen semi gelatinous oil in old bikes and attributed it to incompatible mixes, clearly this is not the case. In that case also mixing the red and blue oil together would probably not cause this to happen either?
The "vaseline" - Could be anything. Lacking lab analysis, no less photos or seeing it in person, all you can do is guess, which is not the optimal way to troubleshoot something - although quite popular on internet forums.

Mixing "red" and "Blue" - In commercial oils, the color is not always indicative of anything other than the color of the oil, thus we would again be guessing.

The short answer? The system is designed to provide the necessary lubrication as built, and the widespread longevity and success of PX autolube attests to this. Why are we beating it to death? There is seriously insufficient information to determine what might have caused the "dimple" on the original gear. Claiming lack of lube is questionable when the "tit" shows no sign of wear, and the shape of the "tit" does not conform to the shape of the "dimple" it is alleged to have caused.
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Aviator47 wrote:
The "vaseline" - Could be anything. Lacking lab analysis, no less photos or seeing it in person, all you can do is guess, which is not the optimal way to troubleshoot something - although quite popular on internet forums.
Thank you for your confidence in me.
Aviator47 wrote:
... Claiming lack of lube is questionable when the "tit" shows no sign of wear, and the shape of the "tit" does not conform to the shape of the "dimple" it is alleged to have caused.
Tit doesn't wear because it's a lot harder material. And yes it does conform to the shape of the "dimple".

This is leading nowhere right now. Let's hope this issue was one of a kind and abnormal. When I put all together gear cog gets nice coat of blue vaseline.
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Partanen wrote:
Aviator47 wrote:
The "vaseline" - Could be anything. Lacking lab analysis, no less photos or seeing it in person, all you can do is guess, which is not the optimal way to troubleshoot something - although quite popular on internet forums.
Thank you for your confidence in me..
My comment was in response to TrumpyScooter, whom I directly quoted when making the comment. Had nothing to do with confidence in anyone, but rather the efficacy of his trying to guess what it is that you call "vaseline".

Since I am working from photos, I will amend my comment about the "tit' to say
Quote:
the shape of the "tit" does not appear to conform to the shape of the "dimple"
The 'tit" appears to still be basically spherical, while there appears to be a very pronounced narrow bottom, as if from a sharp point of contact, in the "dimple". That is the "comformity" that appears to be lacking.

External inline image provided by member with no explanatory text

As to the relative "hardness" of the two items, I have don't have access to any authoritative data, so I will not make any definitive claims about that. Would you be kind enough to share your source of this, so we can all benefit from it?
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Nothing more than my capability to understand technical matters. I also have capability to see things with my eyes.

Just don't think I'm a dumb or retarded if I cannot put english words in right order.
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Here it the "tit": External inline image provided by member with no explanatory text

No wear at all.
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Does the "tit" come to a point? Here is my gear and "tit" from a carb box with about 20,000 km and a well functioning autolube. The contact surface of the "tit" is flat, and the gear face shows no sign of wear.

How does the "tit" shape of my pump cover assy compare to yours? If your "tit" is flat, then it would be difficult to see how a flat surface conforms to the groove in your gear, and could have caused that groove ("dimple"). The contour of the "tit" and the groove would have to match for the "tit" to have abraded the gear face in that fashion. If the "tit" is pointed, than I would suggest we see if others could check to see if "pointed" is "normal". If not, then you might want to consider replacing the pump cover assembly.

How's that sound?
Forum member supplied image with no explanatory text
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Now, back to lubrication of the gear. If you check the hole in the carb box the arrow points to, you will find it mates to an oil galley coming up from the engine casing, fed by the spiral feed that SoCalGuy shows in the drive shaft photo, and leads to an oil outlet inside the pump assy cover. This is the path via which gear oil is delivered to the pump gear.

The oil is splashed and misted up to the spiral on the shaft, in much the same manner oil is splashed and misted to the cylinder walls and piston wrist pin on a 4T engine, by the action of the crankpin journals splashing in the oil sump as the crankshaft rotates. In this case, the splash and mist comes from the gear teeth splashing in the gear box oil. If you want to run a little experiment, chuck that worn gear (which is smaller than the gearbox gears) in a drill, put it about half way down in a cup of gear oil with the shaft horizontal and power the drill up to about 1,000 RPM and see how much oil is splashed up about 30 cm in one minute.
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Aviator47 wrote:
Does the "tit" come to a point? Here is my gear and "tit" from a carb box with about 20,000 km and a well functioning autolube. The contact surface of the "tit" is flat, and the gear face shows no sign of wear.

How does the "tit" shape of my pump cover assy compare to yours? If your "tit" is flat, then it would be difficult to see how a flat surface conforms to the groove in your gear, and could have caused that groove ("dimple"). The contour of the "tit" and the groove would have to match for the "tit" to have abraded the gear face in that fashion. If the "tit" is pointed, than I would suggest we see if others could check to see if "pointed" is "normal". If not, then you might want to consider replacing the pump cover assembly.

How's that sound?
That makes sense. My "tit" seems to be more pointed than yours. Now I wonder why it's that.

If anyone have pictures of pump cover assy could you show it, please?
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yeah i looked at my late px today and its flat, kind of like aviators pic.

im moving more toward yours has possibly been replaced...recently.Perhaps yours is new? Which could give rise to a previously stuck nipple, which the cover has been replaced and not the gear. If the wear is on the widest side it could have worn the same spot, except i dont see any shiny wear marks on that pump. I know aviator has mentioned a possible repair could have been made by the original owner. Can you ask him? Im sure ive seen a pump like that before. In saying that neither px's i have are worn like that one.

perhaps mine started off pointy and got flattened off, but who knows. tomorrow ill look at the older px model cover an post what i see.

What does the underside of that pump look like? what about the carb box itself? clean it and pic please.

As mentioned without actually looking at it its all guess work.
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When I opened the oil pump I found red oil and some metal residues from these holes.

External inline image provided by member with no explanatory text

2-stroke oil was red and oil in gearbox was brownish.

****************

Another thing is that the drive gear doesn't spin when clutch is disengaged. While standing at traffic lights oil splashes are reduced a lot in gearbox. Oil pump spins still. Without oil if it's lubricated by gear oil. Gear oil would also drain from oil pump when engine isn't running. This all is pointless pondering if we now find out that I have wrong or too sharp "tit" at my oil pump cover assy. Nerd emoticon
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TrumpyScooter wrote:
yeah i looked at my late px today and its flat, kind of like aviators pic.

im moving more toward yours has possibly been replaced...recently.Perhaps yours is new? Which could give rise to a previously stuck nipple, which the cover has been replaced and not the gear. If the wear is on the widest side it could have worn the same spot, except i dont see any shiny wear marks on that pump. I know aviator has mentioned a possible repair could have been made by the original owner. Can you ask him? Im sure ive seen a pump like that before. In saying that neither px's i have are worn like that one.
Someone have definitely opened this before. Signs are obvious. Some filings have done for carb box inlet. I probably see the previous owner some day and maybe I should ask what was going on. Everything else seems to be fine.
TrumpyScooter wrote:
perhaps mine started off pointy and got flattened off, but who knows. tomorrow ill look at the older px model cover an post what i see.

What does the underside of that pump look like? what about the carb box itself? clean it and pic please.

As mentioned without actually looking at it its all guess work.
I'll take some more photos.

I found this online and it looks similar than mine.

http://bilder1.eazyauction.de/LTH/artikelbilder/8835.jpg
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Carb box bottom.

External inline image provided by member with no explanatory text
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Could very well be that a brand new 'tit" is pointy. I have never had the need to open a new pump assembly. If it works, I tend to leave it alone, there is no scheduled service for the assembly and the carb box can be removed with the assembly left assembled.

Sound engineering techniques for an assembly like this would be to make the "tit" from metal of slightly less hardness than the gear, as it is the gear surface that needs to be "protected", not the "tit". The gear will travel the same vertical distance as the "tit" wears down, and vertical distance is what meters the oil, not absolute position. Uneven wear on the gear surface can affect the vertical stroke. Thus, it would make sense for the "tit" to wear flat with time.

While I would never claim to be spot on via internet pictures and discussions, I go back to what I said here. I suspect that someone mis-assembled the pump in the past (most likely), something unknown caused the shaft to bind (less likely) or the gear was damaged to begin with (even less likely). If the gear was prevented from making full downward travel, that would most likely not only cause damage to the gear surface, but would seriously damage the "tit". Perhaps this occurred, and only the cover assembly was replaced, as the "tit" damage was not only more noticeable, but the person doing the work did not realize how important the integrity of the gear surface is.
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I'm calling it a bad installation. FWIW, still looks to me like someone with a heavy hand gave the gear a whack - possibly with the tip of a flat blade screwdriver - trying to make it fit, not realizing how it would affect the operation of the mechanism downstream.
Aviator47 wrote:
It would make sense for the "tit" to wear flat with time.
In this context yes, fortunately for us, not in others.
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Partanen wrote:
Carb box bottom.

External inline image provided by member with no explanatory text
Here's a brand new one I have and it's marked 4B as opposed to his "4A". Otherwise looks the same.

Anyone know the dif? if there is a difference!
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different mould, thats probably all of the difference
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joshzingzing wrote:
different mould, thats probably all of the difference
^^^^^ is my guess as well.
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SoCalGuy wrote:
I'm calling it a bad installation. FWIW, still looks to me like someone with a heavy hand gave the gear a whack - possibly with the tip of a flat blade screwdriver - trying to make it fit, not realizing how it would affect the operation of the mechanism downstream.
The shape of the groove is not consistent with a single blow. It appears to be a nice radial shape.

The damage to the gear is weird. Based on VespaLabs info, the gear turns at about 12 RPM at idle, and the groove is located where the "tit" would ride at idle. A groove of that depth would be difficult to abrade away at that RPM without some seriously major pressure on the point of contact, and since the "tit" is the sacrificial metal, it's even more bizarre.

Again, just speculating via photos, but if the "tit" had ridden in that groove for any serious amount of time, you would expect to see some lateral wear on two sides of the "tit", conforming to the sides groove, and nice curved surface on the other two "sides". Even if the groove had been there to begin with, as TrumpyScooter suggested, the "tit" would have conforming wear on the two sides contacting the groove. That doesn't appear to be the case, and thus my earlier suggestion that the previous owner did something that lead to a noticeable failure, and had to replace the assy cover.


Way too difficult to determine cause by internet. My training and experience in teardown fault analysis never included the modern, advanced techniques of "virtual" inspection and analysis.

Suffice to say the gear needs to be replaced (which Partenen has done) and then move on to something else.
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I saw the previous owner. He said that he have never opened the oil pump. This may remain mystery.
⬆️    About 5 months elapsed    ⬇️
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I just read through this thread, and my first impression when I saw the side-view pic of the damaged geared cam, was that at some point it had not been rotating for a long time and the wear was the result of the 'tit' and/or arm sweeping back and forth in the same location, which is what you would expect to happen if the gear never moved and the throttle was being opened and closed over and over. Later, somebody may have replaced the pump top, which would explain why the 'tit' showed virtually no wear.

I hope the OP made sure the gear train was intact or else his efforts to fix it may have been in vain. I think this might also happen if the pinion gear were installed upside down, but I'm not sure it the top would still fit.
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After seeing this very similar picture, I wonder if this is not as "unusual" as we think.

I would question your hypothesis, jim, since if the wear was due to the arm sweeping back and forth over a stationary gear, the groove would be more outward along a radius, sweeping out with the arm movement, rather than following an almost constant, equidistant arc from the center of the gear.

My hypothesis is that, since the groove is located in the "throttle closed" position, there was some sort of ongoing, short term impediment to free up/down travel of the pump shaft. Perhaps binding when the engine is "cold" and warming up. Thus, every time the engine was started, and idled to "warm up", the resistance to up/down movement caused greater wear, but after 30-45 seconds, the "binding" lessened to where the resistance was reduced. Also, lube level between the "tit" and the gear surface would be less when first started than after running for a while, as the oil has to get up there. Thus, during initial idle, more resistance to up/down movement along with lessened lube.
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I have to admit, I was quite surprised at the condition of the pump gear when I dismantled the autolube for cleaning...but it's interesting that I'm not the only one to have experienced the issue, as per the OP's thread.

When I dismantled my carb and autolube, I discovered that the previous owner had installed the wrong gasket on the base of the carb (practically blocking the 2T oil feed into it).

One thing I've noticed form looking through some of the images in this thread is the difference in the position of the steel cylindrical bushing (used for centering carburator box on engine casing / oilpump shaft).

Looking at my carb box, it does appear that this part has either been filed down or has been worn by the gear...although there doesn't appear to be any signs of wear to the teeth or the underside of the gear.
But I do wonder if it should be recessed further down?

edit: with regard to Partanen's "vaseline" and how the top of the gear is lubricated, I've seen a genuine Piaggio pump cover (still factory sealed) and it did in fact have a blob of red grease on the nipple / tit.
Probably just for the initial run in of the the pump, although I wonder if it might be good practise to put a fresh blob on the nipple whenever the autolube is dismantled for cleaning.

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Molto Verboso
2005 PX150 In a Part-time Relationship with a 2-Stroke Vespa Since 2007
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Molto Verboso
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If you look at the case half where that sleeve seats, it will appear machined such that it should initally be seated there, not in the carb box, and it so just happens to usually come out with the box during removal. In fact that's how I reassemble, sleeve in case, then pinion gear, then carb box.

Yours is definitely not right and appears damaged by the gear because it was sticking up way too high into the box.
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Molto Verboso
2005 PX150 In a Part-time Relationship with a 2-Stroke Vespa Since 2007
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Molto Verboso
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Quote:
Does the "tit" come to a point? Here is my gear and "tit" from a carb box with about 20,000 km and a well functioning autolube. The contact surface of the "tit" is flat, and the gear face shows no sign of wear.
I've seen a new one and it is a rounded point, but there are lots of photos of ones that show a flat spot after many miles/kms, and I don't believe it makes any difference.

Since the spring keeps the cam up against the cam follower or 'tit', and since what really matters is the piston's stroke length, as the tit wears down the cam may rise a little but it's still maintaining the same stroke length as before at any given throttle position. I think it would have to be gone so far that the lever starts riding on the cam to go wrong, and even then the stroke length would still be appropriate, but it would definitely be reading the throttle position wrong by then.
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Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
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@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
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Location: Paros Island, Greece
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pdxjim wrote:
Quote:
Does the "tit" come to a point? Here is my gear and "tit" from a carb box with about 20,000 km and a well functioning autolube. The contact surface of the "tit" is flat, and the gear face shows no sign of wear.
I've seen a new one and it is a rounded point, but there are lots of photos of ones that show a flat spot after many miles/kms, and I don't believe it makes any difference.

Since the spring keeps the cam up against the cam follower or 'tit', and since what really matters is the piston's stroke length, as the tit wears down the cam may rise a little but it's still maintaining the same stroke length as before at any given throttle position. I think it would have to be gone so far that the lever starts riding on the cam to go wrong, and even then the stroke length would still be appropriate, but it would definitely be reading the throttle position wrong by then.
jim

Forgive me for not being explicit.

You are correct. The height of the "tit" has no impact on oil delivery rate.

However, the thickness of the gear on the thicker side in relation to the thinner side does. Thus, if one of the two components were to be made the "sacrificial" one, it would be the "tit", as sacrificing thickness of the gear would have a deleterious effect. In the pics, it clearly looks as if there has been abrasive "sacrifice" of the gear surface.
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pdxjim wrote:
If you look at the case half where that sleeve seats, it will appear machined such that it should initally be seated there, not in the carb box...Yours is definitely not right and appears damaged by the gear because it was sticking up way too high into the box.
Thanks, Jim, and yes you're right about the case being machined to fit the bushing / sleeve. Unfortunately I can't seem to push the sleeve further down into the carb casing as it is held fast in it's current position.

To avoid damaging or warping the carb box by further attempting to remove the sleeve, I've now used a Dremel to file away the sleeve so that it is now flush.

The gear now spins without any resistance, even when it is fully pressed down.

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@snappa avatar
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Hooked
Vespa T5 Classic
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Right, fingers crossed I'll be able to get my autolube back together within the next few days or so as a friend from another forum is sending me a spare PX autolube pump, which appears to be the same one as used in the T5
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Hooked
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Finally all back together, including new check valve ball and spring (re-used the old nylon bushing).

Replacement autolube gear looks in much better shape (completely flat), so fingers crossed I shouldn't have any more problems.

External inline image provided by member with no explanatory text
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