OIL PUMPS

[jiw]

Hi all, just pulled the oil pump off my car, problem was it was struggling to gain oil pressure. once gained pressure was held fairly well, upon stripping the pump this is what was found:


The rotor's are slightly pitted and scorn on the diameter's, this is slightly!!

The casing has some very very light pick up marks on it, i dont think it is any great concern but i shall post pics up later.


What really got me was the pressure valve piston was jammed fully open (with the spring's compressed), im not 100% sure how this work's, does the valve need to be closed so that the oil out of the oil galleries does not drain away and so that the pump can gain pressure quickly, therefore it will pressurise the system quicker ?


i would love to just buy a set of rotor's and a service kit for the valve as it will be over £300 if i have to buy the full unit, help and advice appreciated, jeff

 

[antilag]

on my rebuild i replaced the inner and outer rotor and changed the valve quite cheaply but my engine failed after 600 miles threw oil pressure and we dnt really no the fault yet

im not saying its anything to do with the oil pump but i wish i replaced it now for piece of mind

 

[jiw]

has anybody else had any of my problem's, views and solutions are appreciated, pics to come when i sor my photobucket out, jeff

 

[ard1ey]

If you've got the pump out, the book says the following clearances should be:

(1) Outer gear to casing - 0.114 to 0.200mm
(2) Inner gear to outer gear at tips - less than 0.18mm
(3) Body to inner gear clearance - 0.05 to 0.09mm
(4) Body to outer gear clearance - 0.05 - 0.11mm
(5) Inner gear to brazed portion of housing clearance - 0.045 to 0.091mm

The regulator valve should be visually undamaged and if you coat it with clean oil it should drop into the front cover under its own weight. This valve is supposed to make sure the pressure doesn't exceed a maximum figure by bleeding off some oil, so if its jammed this is probably your culprit.

 

[jiw]

http://img.photobucket.com/albums/v187/escgti/gtir engine related/P1010004.jpg

http://img.photobucket.com/albums/v187/escgti/gtir engine related/P1010001.jpg

pics aint too good, i can get away with lapping the inner casting on a lapping table to remove any scratches and ensure flatness, could do with just replacing he serviceparts as the difference in between replacing the entire unit and the service parts is £250 plus, cheer's, jeff

cheer's for them clearences mate, i shall give them a check!!

 

[Japmonster]

I had same problem of oil pressure taking a while to build up, then i lost oil pressure completely. Thought it was best to replace everything, oil pump, oil pump housing (as this was damaged) and oil relief valve thing as this was also damaged!! I got garage to do the work, so i only know what got changed and not how hard it was to do or anything like that!!

 

[jiw]

sorry for my late reply, i stripped and inspected the pump at work, it seems that the flow control valve(piston) bore was 0.26mm oval, this was causing the piston to jam at an angle, i could ream the housing and machine a new piston but im not sure how this will affect the flow control, i think im just gonna bite the bullet and get a new pump, got a quote off mjp for £285 + v.a.t, does anybody know anywhere cheaper? cheer's jeff