Technical Oil Pump Dots - Fiat Stilo 1.8 16V

[burtontrent]

Fiat Stilo 1.8 16V 192 I am trying to establish as most 'Oil pump' Dots go together, you normally get one dot, between two dots, on this pump one dot is underneath and one on top, it is quite hard to be sure that they align?
This is not normal engineering procedure that I ever learned when doing an apprenticeship. I have an 'emanual' but I'm sure it is not shown in this how to install the two gears? Any ideas anyone? Can post pics if you wish?

 

[124BC1]

I'm not familiar with the Stilo 1.8. Would it be possible for you to post a pic?
Does this oil pump have 2 gears that mesh or is it an eccentric orbital type?
If a 2 gear type, are you assembling it correctly?
Maybe you could duplicate the underneath mark onto the top of the gear using a felt tip marker or similar and thereby see clearly if the 2 marks align?

 

[burtontrent]

I'm not familiar with the Stilo 1.8. Would it be possible for you to post a pic?
Does this oil pump have 2 gears that mesh or is it an eccentric orbital type?
If a 2 gear type, are you assembling it correctly?
Maybe you could duplicate the underneath mark onto the top of the gear using a felt tip marker or similar and thereby see clearly if the 2 marks align?

 

[burtontrent]

Here are 4x photo's of the puimp I've marked the dots in 'Yellow' as you can see the inner gear the dot finishes up on the inside. The outer gear dot can be inside or outside, can place it both ways. However, as you can see both dots could be placed to the right or to the left of the other dot. There are only 2x dots. I've always seen 3 dots on older vehicles with this type of pump. The Emanual on the 1.8 16V makes no gesture about where to place the dots? It is not even mentioned in the manual? Pic 3x the dot on the 'inner' gear in directly underneath the outer dot on the outer, that is the only way I can see it is useful to anyone? Any ideas' Feel freee to comment.. Thanks for your reply 124BC1

 

[124BC1]

Thanks for the pics, they make things a lot easier to understand. I too, am familiar with aligning 1 dot between 2 dots on 2 meshing gears e.g. old motorcycle engine valve timing etc. or to ensure that gears continue to mesh in the same way as they had 'bedded-in' to avoid possible problems.

I've done a bit of checking in some car workshop manuals I have (I don't have anything on the more modern models, just the old stuff) and found some info on a very similar oil pump that was fitted to the GM/Opel/Vauxhall 1.3 litre ohc engine of the 1980's. Here's the relevant page (below) - if you look at pic 38.4, it points to 'Gear outer face identification mark (arrowed), also in the text, paragraph 4 of section 38 Oil Pump - overhaul, it says " Note that the outer gear face is marked for position (photo)". On this engine the inner gear can only be fitted in one way but the outer gear could be fitted in 2 ways, so a mark is used to show the correct way.

I also checked a manual I have for the Toyota Corolla 2002 - 2007, this has a broadly similar oil pump and it states -"when reassembling, lubricate the pump rotors with clean engine oil and place them in the pump body with the marks facing the pump body cover side" i.e. the marks should be facing outwards - there's no mention of aligning them to each other or anything else. So, my reading of these marks is to simply show which are the outside sides of the gears/rotors when inserted in the pump body. Therefore imho, inserting the gears as per your pic # 4 should be fine,(famous last words ) as they are facing outwards and are also somewhat aligned with each other (even if it's not strictly necessary).

 

[burtontrent]

Thanks for the pics, they make things a lot easier to understand. I too, am familiar with aligning 1 dot between 2 dots on 2 meshing gears e.g. old motorcycle engine valve timing etc. or to ensure that gears continue to mesh in the same way as they had 'bedded-in' to avoid possible problems.

I've done a bit of checking in some car workshop manuals I have (I don't have anything on the more modern models, just the old stuff) and found some info on a very similar oil pump that was fitted to the GM/Opel/Vauxhall 1.3 litre ohc engine of the 1980's. Here's the relevant page (below) - if you look at pic 38.4, it points to 'Gear outer face identification mark (arrowed), also in the text, paragraph 4 of section 38 Oil Pump - overhaul, it says " Note that the outer gear face is marked for position (photo)". On this engine the inner gear can only be fitted in one way but the outer gear could be fitted in 2 ways, so a mark is used to show the correct way.

I also checked a manual I have for the Toyota Corolla 2002 - 2007, this has a broadly similar oil pump and it states -"when reassembling, lubricate the pump rotors with clean engine oil and place them in the pump body with the marks facing the pump body cover side" i.e. the marks should be facing outwards - there's no mention of aligning them to each other or anything else. So, my reading of these marks is to simply show which are the outside sides of the gears/rotors when inserted in the pump body. Therefore imho, inserting the gears as per your pic # 4 should be fine,(famous last words ) as they are facing outwards and are also somewhat aligned with each other (even if it's not strictly necessary).

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Thank you very much for your reply, It certainly makes me feel more assured that it is right to go. The pump turns nice and freely so I guess we are on the money! Thank You!! Burton