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Ok, I've been waiting for my engine to rack up 1000ks to make sure nothing goes bang.

I bought parts through a friend of a friend, and he supplied mahle forged pistons.

He also neglected to inform me that they foul the oil squirters.

So, after the first piston was in, went to turn the crank over, and it got real hard.

From here, I checked to see what was happening....

What i found was the piston fouling the squirter.

So? What do i so now?

Answer: mod the squirters to fit.

I have attached(hopefully) pics of the modded squirters, with pics of installed so you can see where they foul, and how little room you will have.

Ok, first things first:

post-37584-0-94172700-1326715016_thumb.jpg

You will have to grind the locator flat.

I used a bench grinder.

CAUTION: being a small amour of alloy, it gets very hot, very quick.

Second:

post-37584-0-39635600-1326713647_thumb.jpg

Grind the back edge of the squirter at an angle.

Third:

post-37584-0-62394600-1326713902_thumb.jpg

As you can see her, I have used a copper washer.

The piston comes down to the point where it nearly contacts.

My thoughts were, I don't want to risk inertia just bringing them into actual contact.

Better safe than sorry.

Fourth:

post-37584-0-60415400-1326713755_thumb.jpg

post-37584-0-49816100-1326713828_thumb.jpg

As you can see here, positioning of the squirter is critical!

Too far one way, it will hit the under piston bracing.

Too far the other, it will foul the rod.

You can see where the locator would have gone.

To torque without the squirters moving, I used a pair of long nosed pliers in the locating hole.

And done them up to the highest point of factory torque specs.

I can't remember, but I think I also used a drop of loctite.

So, there you have it.

As stated, have been running my engine for 1000kms now, without incident(touch wood).

I've also had my engine spinning at/near redline.

Any questions, pm me.

Hope this helps others, as I couldn't find much on it other than people saying, "yeah, I've heard they foul."

Cheers, happy modding....

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I'm guessing loss of oil pressure.

And i was building in my garage, don't really have the equipment needed to notch a piston.

Don't really know, but some may, would notching the piston weaken it?

Thinking about it, I think it would.

But thanks door the comment.

I appreciate feedback, and other ideas.

the piston wouldnt really vibrate if one side was notched as it is reciprocating (up and down) only, if it was rotating then it might make a difference

weight matching to the lightest over all weight is all that is really needed

if you do notch the pistons then dont forget to debur them

though i more think that getting the right pistons is the right way to do things from the start, if not then this way should be plan b

hey luke do you know if it alters the angle or the spot the oil squirt hits?

the piston wouldnt really vibrate if one side was notched as it is reciprocating (up and down) only, if it was rotating then it might make a difference

weight matching to the lightest over all weight is all that is really needed

if you do notch the pistons then dont forget to debur them

though i more think that getting the right pistons is the right way to do things from the start, if not then this way should be plan b

hey luke do you know if it alters the angle or the spot the oil squirt hits?

Ok, keep in mind the following are only MY thoughts and opinions, and this is the first motor I have rebuilt....

In regards to the balance of the piston,,,,

If you were to take material from one side and not the other, this would cause an off balance, and would make the piston want to "tilt", under the stress of high rpm, causing the difference in weight to multiply, I would think the piston would want to tilt more and more, like a see-saw out of balance.

This would in turn, cause higher wear rate on the edges that the piston wants to tip to.

In regards to the oil angle and hit zone,,,,,

No, it does not alter the angle the oil will hit at, as all the mounting surfaces are parallel, and the squirter is not bent.

The hit zone is a different story.

As the squiter has been twisted, it will now hit a different part of the piston, but keep in mind, they are different pistons being used.

The oil still hits the bottom of the piston, as intended, just in a slightly different place.

Hope this helps.

Again, my views and opinions, others may vary.

I appreciate the feedback and interest though guys.

Wouldn't putting a thicker copper washer under the squirter been an easier fix?

If you see the pics, that's what i done, as well as repositioning them.

The washer would have to be approximately 5-8mm thick, and the factory banjo bolts arnt long enough to allow this.

Space it out too far, and it will also foul the counter weights on the crank.

lucky my pistons (CP) came with the cutouts for the squirters :D cant u just cut the pistons section out and get them re balanced ? i wouldent alter the position of the standard squirter because if Nissan engineered it that way its for a damn good reason right ?

<br />But you got a perfectly balanced piece of metal sitting on a pivot going up and down. I know there isn't much room in the bore for movement, but i'm probably talking about stuff I don't know lol.<br />
<br /><br /><br />

If that were a real issue, then all the pistons that have the gudgeon pin offset to one side would have problems. And they don't.

  • 1 year later...

hi i'm going to be fitting 87mm mahle pistons to my own block - i just wanted to ask how your car is running now after 1000km and i'm guessing a remap too?

just wondering as this seems to make sense but wanted to see if theres been any issues? I cant see how personally.. I read a 2.5mm washer is enough to 'lift' the oil jet (squirter?) so it clears the piston skirt?

ta

ant

hey maye.

ran fine for about 2500kms.

then I was limiter bashing on a skid pan, and bearings let go.

the squirters are still fine, and in position.

in relation to the extra thick washer, from memory, 2.5mm may have been enough, but it would squirt directly onto the bracing, not under the piston head which is where its meant to go.

either way, good luck.

If you see the pics, that's what i done, as well as repositioning them.

The washer would have to be approximately 5-8mm thick, and the factory banjo bolts arnt long enough to allow this.

Space it out too far, and it will also foul the counter weights on the crank.

also, see this post, just above.

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