Hello all my name is Stefan Aka Navo I'm currently in the process of building my first fiat engine, I'm using the 126 650cc engine for my 1972 500.

I'm undergoing the process of adding a oil cooler to it but instead of using a generic kit I'm welding a take off on to the oil pump housing.

What I need is a little confirmation as I've seen All sorts of opinions.

I've been told that I need to add a restriction to the driven pump gear with a 2.5mm hole in it.

What is would like to know is, is this correct info? Does it affect the lubrication of the engine by changing its original path?

Please bare with me as I'm turning to the knowledge of the community so I can build this car properly.

Many thanks in advance

Said threaded insert pictured bellow

Apologies for the slow response---problems with a 98yr old mother who insists on living on her own still!! Yes, you tap a thread into the end of the DRIVEN gear, and then screw a bolt in to the threaded hole (don't forget to loc-tite in in!) and then drill a 2.5mm hole through the insert. If you don't drill the insert the oil pressure will build up to the point it will blow out seals.

Where about in the UK are you Navo? always helps to put people together.

I'm from West Bromwich mate

the hobbler said:

Apologies for the slow response---problems with a 98yr old mother who insists on living on her own still!! Yes, you tap a thread into the end of the DRIVEN gear, and then screw a bolt in to the threaded hole (don't forget to loc-tite in in!) and then drill a 2.5mm hole through the insert. If you don't drill the insert the oil pressure will build up to the point it will blow out seals.

Click to expand...

What I wondered is if the oil is forced to take a new path does the old path suffer from its lack of oil flow

And no worries about the late reply I'm used to being insulted so this makes a change

I am not aware of anybody suffering a lubrication problem when this mod has been carried out---and it has been done a lot of times.
I am in North Wales (just--long story) about 3 miles from the centre of Chester.

Brill ok well I have added the thread and put a stainless steel grub screw in it I just need to drill the 2.5mm hole

And nice to know this forum has some helpful people on here rather than the other forums I'm used to

So in view of this I showed a fellow fiat nut and he is certain it's not needed ! I'm so confused he said why should it be a good idea to close it's original path I explained the principal it's just left me confused. I'm going to be using an6 oil lines to the cooler btw thanks for your help so far

I accept that you may not want to take my word that you need the 2.5mm hole in the blanking 'plug', but be assured, you do, and my advice came from the foremost 'Classic Abarth' company in the UK--in writing!

No that wasn't the case I'm sure you are far more than myself on the matter that's why I turned to everyone for info thanks !

We are a friendly bunch here. But I'm sure we can provide some abuse if this will make you feel more at home!

Welcome to the forum, got some pictures of your little beast?

Lol it sure makes a change to what I'm used to my other forum adventures have included insults, big egos, slanging matches and generally useless responses haha I shall get some later on for you she's currently undergoing a facelift in a local body shop to tackle the good amount of rust aka weight reduction she has

I may start a build thread if I can find where to post it haha

Just saw your question so in a case you haven't seen my post you may take a look about my oil cooler installation. All discussions and search conclude in blocking and opening a 2.5mm hole. Mine is running for 2 years now with no problems and it is very effective. Have in mind that welding a takeout on your oil pump cover might deform the oil pump housing and gears when you assembly the pump might be stuck. Had this problem and had to take down with a small file the deformation area which was something like a bubble in a size of 0.3X2X6mm.

Anyone know the thread on the crank case for the return ?

M8 i think

Maybe it is M12, i reed some of my old posts here.

I think that it is 12mm Thomas---definately NOT 8mm