hi

was just wondering if subaru made an improvement on the newage sti oil pumps? and whether they are still worth uprating or not?

as i know its recommended with the classics, specially at timing belt change time..

cheers

 

As above have a 2002 sti and was wondering this too.
BTTT


Mark

 

Anyone ????

BTTT


Mark

 

Standard Pumps are the same, flow rates aside. The main issue on the older cars is the pumps backing plate screws working loose over time.

 

Your existing pump can be rebuilt with a different design of plunger.
Ask Harvey, or API.

 

At APi we adopt the same approach as Cosworth, we de-burr and polish all the interior passageways and micro polish the relief valve itself. We do not change the relief valve shape, in the same way that Cosworth don't either.

We also de-burr both of the gears. then reset the pressure to give 7 bar and off we go.
We can quite happily work with a used pump and we have an exchange programme to make things easier for people.

We supply/offer 10mm or 11mm or 12mm pumps and must get back like for like in the exchange programme. Cost is usually £100.00 + VAT for a rebuilt pump, repainted in natty red crackle, so we can tell which ones have been done.....

Other than the odd one with debris damage on the gear faces, very little goes wrong with them *. Except that over a period of time, the screws holding the backplate on come loose. They are rarely loose at the first cam belt service, but usually are at the second. So we recommend a modified pump at cam belt change time - on any Impreza turbo engine.

* the other damage is quite often caused by worn thrust faces on the crank /block which causes ' plunge ' of the internal gears as the crank moves back and forth. That wrecks the pump internals.

David APi

Happy New Year all

 

is there no way to check the screws on the backing plate at timing belt change time?

 

How big a job is it to swap one then? I hate this forum fear factor that builds up on some posts.
Basically you are saying that your oil pump is gonna fail?
If not, what are you saying? These loose screws, what of it?

 

As a ' home ' job, the problem is getting the belt drive gear off the crank. They are a super tight fit and can challenge many a good professional mechanic. There are holes in the gear that suggest a puller. But the holes are not threaded.

So people start levering and then snap off one [ or more ] of the crank triggers on the tin plate attached to the back of the gear. At that point you are in deep doo-doo.

But once the gear is off, there are 5 or 6 bolts holding the pump on to the block. There is only a rubber o ring seal to the block and of course the crank seal itself to change. Not a hard job by any means, but has the ability to turn into a nightmare in clumsy hands.

My opinion; it is a job best left to professionals.

David

 

The screws cannot fall out and get in anywhere. But they do allow oil pressure to leech away out of the side of the pump. Any gas or fluid [ and humans ] will always take the path of least resistance. There are no signs of the screws coming loose, as the lost oil pressure merely drains back inside the engine, it does not leak outwardly.

Thus, as the engine gets older and the screws get looser, the oil pressure is weakening just when the engine needs it most.

Not so much a fear factor just trying to point out how best to maintain your engine best.

I don't think that we have done a cam belt change for years without changing the pump. Customers seem to value the opinion that preventive maintenance is best.
David

 

M8 tap, 2 x M8 bolts and a bit of steel plate with a couple of strategically drilled holes works well

As David points out, the backing plate screws are prone to working loose on an OE pump - I've seen this a few times, the worst outcome being a 'rattled out' bottom end

 

Ta for the info David, but I dont see why you would want to change an oil pump when all it needs is the screws tightening? You said earlier that very little goes wrong with them, so why change it then for the sake of it? Surely all it needs is them screws sorting?
I had better keep a good eye on my Defi's then as my 100k cambelt change is coming in a years time.
My more immediate job is changing my BB for a quieter one! I am getting on a bit and the noise and drone is bugging me now. Not to think for some reason after 6 years i have somehow started worrying about what the neighbours must think????
Wow, now i am getting old! LOL.

 

same, thats what i was thinking above.. however how much does a new oil pump coost? dont think its much so for preventative maintenance probs is worth it..

im coming up to second timing belt time too in 1 year so that means waterpump, belt and oil pump at same time..
hmm..

 

Modded/serviced oil pump is a LOT cheaper than a new engine.............trust me

If David at API says it's a good idea, then it's a good idea. He is an EXTREMELY honest, straight guy, not just out to make money. His advice is solid copperbottomed.

But in the end, it's your car, and you make the choice.

 

I understand. Ain't trying to slight anybody here, just asking the questions i am thinking.
Whilst we are on the subject of oil pumps, what gets changed in the RCM modified pumps, does anybody know?

David Can you post a piccy of the red 'crackle' paint job you were on about please? I am intrigued!

EDIT: Amazing what you find on RCM webby, LOL.
Quote, "Each pump is carefully checked, given a serial number and then modified to incorporate a different pressure relief valve ensuring greater reliability and peace of mind to your Impreza engine.
Please note that flow rate remains unchanged."

 

bloody hell rcms is £212

plus £200 for water pump and timing belt..

call it £500 for the lot.

Possibly save £80 or so using APIs modded pump..

fair enough, at least i know what to expect, my original 200 quote had just doubled lol

 

The red crackle looks alot like the intake manifold.

got the API one on my 98 sti now curtosy of API. however have noticed a couple PSI lower warm idle since the change.

 

Water pumps appear to last forever on a scoob, if it ain't broke don't fix it........

There ought to be an oil pump pic on our web pages soon, I can't do the picture thing on here [ too bloody old ]

There is no reason on earth why you cannot just take off your original pump clean it all up, sort out the screws problem and put it back on again. That'll be better than nothing. But our pumps are an improved bit of kit. They take about 2 hours to create.

Flow rate of a subaru oil pump can never be changed, the flow is controlled by the gears which are attached to the crank. Short of fitting a new gear set the flow must always remain the same. Just the pressure can be altered.

David

 

i didnt know water pumps didnt have problems on scoobs? (always had them go at some point on previous cars)

so i can pass on that and just do belt and oil pump?

just looked through history august 2006 my timing belt was done which was 20k ago, so if i aim to do it after jan 2011 but before the summer, i should be fine.more time than i expected.

i defo no i wont have done the milage by then lol