Hi all, Ive got 2 standard 10mm used oil pumps and wondered if there is a way of checking for wear etc to see which i should use, or if it's worth doing rather than just spending near on £200 for new one. Or are there companies doing checks etc?

Both pumps look good inside(no scoring etc). Also shimming the relieve valve spring to increase pressure? How thick a washer/washers need to go in??
Cheers for help
Pete

 

If you send your pump to someone to check it over will cost you, to modify (needs to be doen by some who knowswhat to do) will also cost you, the cost of sending it off etc..., adding all the cost i dont think its worth doing on a used pump, buy a new pump and you are sorted. IMO

 

ive heard about the shim mod but imo dont think its worth it, the problems with the oil pump arent to do with lack of pressure

 

Does shimming the pump increase oil pressure?

 

A high flow upgraded oil pump ( 11mm or 12mm) is a better option, and it will last a long time for under £200.

 

yes

 

Thanks for the reply, can you explain how that works as I may do it mine and can it be done in situ?
Cheers

 

the oil pump problem is a big can of worms, imo it doesnt cause all the problems it gets blamed for so i would leave alone, also the uprated 12mm pumps can cause more problems than they solve in certain situations.

to explain how it does work basically the shim is stiffening the spring so it doesnt open as early to bypass the oil therefore you are running higher pressure before the bypass valve opens. as said before the oil pressure isnt a problem and the oil pump already flows more than enough

 

Would it increase pressure at idle if I carried this mod out?

 

doubt it very much

 

Thanks for thoughts and advise on this, did think people would say not to reuse oil pump in a rebuild but when spending £££ on everything else another £200 seems a lot when I poss have 2 pumps that have nothing wrong with them.
Do any companies offer a test (what cost?) or anyone know of procedure to check for wear??
Thanks again.

 

as above probably not

 

its upto you , do you know if they came out of good engines.

i would have thought any of the proper engine builders like api etc would check it for you

 

We do exchange modified oil pumps that are hand built and fettled here in our workshops. We flow the internal galleries a-la Cosworth style [ they copied ours - not the other way around ] Micro polish the relief valve and its guide channel.

We run them on a rig and reset pressure by carefully shimming the relief valve spring. Then all painted red crackle so that it is easily recognisable when fitted.

Including the seal and O ring £125.00 + VAT exchange.

Form a queue here guys.

David APi

01926 614333

 

...And I have one!

 

Sounds like the Exchange option is a good one via David at api.
I take it these are a like for like option advi have 10mm pump, what bhp are these good for once fettled and uprated??
Cheers
Pete

 

Well Danny Clarks Sti Vers 3 car runs 654 hp on one - good enough for you ??

Yes like for like 10 mm for 10, 11 for 11 etc. but unless you have a car that has VVT or twin VVT there is no point in fitting a higher capacity one. And we would charge retail money if we didn't get back a useable like for like exchange unit.

David

Ps we usually ask for a £50.00 deposit until the old unit comes back. That just makes sure we get one back, rather than having to chase. No time limit on returning it. One took 7 months to get here from France, he still got his deposit back.

David

01926 614333

 

Any problems on fitting a 12mm on 2.5l fully forged?

Sorry OP for highjacking.

 

I think Dave explains it quite well:

This....doesn't matter what valve or spirng is in there its a bit usless if it sticks in the bore of the guide.

and:

Anyone can stick some extra washers/shims in, but how many and what net effect won't show for anything unless its actually tested.


One question...do you do anything extra to stop the screws comming loose? Just use some good high temp/strength/oil+fuel resistant thread lock?

 

Our pumps have proper countersunk Stainless " Allen screws" fitted. they can be torqued properly and with a small amount of threadlock. Try getting 'phillips' headed screws out that have been thread locked -

GOOOOOOOOD LUCK with that.

No reason why a 12 mm pump won't fit on any engine.

David APi

 

I hate Philips and Posi screws on engines......with a vengeance.

 

Any benefits on fitting a 12mm rather then fitting a 10mm pump?

 

Only mental ones that make you feel good. I M didn't fit a 10mm pump on by sheer luck Their engineers have calculated that 10 mm is what is necessary and they would have had far more information at their fingertips than any of us.

It is only latterly that 11 and 12 mm pumps with increased flow capacity have come available and that is more to do with a decent quantity of oil being necessary & available for the Variable cam timing type engines.

Obviously it cannot do any harm fitting a larger capacity pump - but that will introduce friction and load onto the crank nose and will have a drag effect.

David

 

From our website.

http://www.apiimpreza.com/frames/pro...&categoryID=31

 

Cheers David