Anybody here ever replaced piston squirters?

[fastfredracing]

I have searched, and read a few threads about it. Was hoping for a little more insight.
Was ready to assembly my 930 bottom end this weekend, and instead , spent most of the two days trying to get my squirters to open . I have 4 out of 6 open, but two of them are stuck open, and flow in either direction. I can also see metal debris in one of the stuck ones with a magnifying glass.
So, my plan is to carefully dremel off the stakes holding them in, and try to gently slide hammer them out. ( not sure if I will have to drill and tap them yet) I may heat the bearing web slightly to help loosen the locktite that I am assuming is already there.Installing them seems like it should go smooth, just worried about the removal process. Any advice appreciated. I have never done this before, and have been lucky enough in the past to get them to spray nice.

[haasad]

Hi, I just did this to my 7R cases. It really wasn't a problem . First it is essential to remove the internals of the little squirters to do this I drilled by hand at 6.0 mm diameter directly into the accessible side of the squirter to a depth of 3 mm . This removes the rolled lip that holds a small alloy disc with the squirt hole in place. Behind this disc is a spring which bears on the steel ball which acts like a little valve allowing the oil to pass up through the squirter. Now you need to hook out the disc , the spring and the ball. If the ball is stuck it can be blown out with an airline from the oil gallery. You are now left with an aluminium cylinder with the ball seat at its bottom stuck in the case web.

I waited for the new squirters to arrive so I knew the outside diameter and depth to drill to. I think mine were 6.2 mm diameter and 25 mm deep but am not sure . The new ones give an easy guide.

I did not heat the case web but simply drilled very carefully right down through the old part at 6 mm diameter. The alloy is soft and the mag 7 r case relatively harder to cut so the drill almost self guides and its very obvious when you are right through.

I then opened the hole up to size with a 6.1 mm drill ( they always cut oversize) to leave a new bore for reaming at 6.2 mm diameter( using a backed off drill ) ready to accept the new squirters.

The new squirters were a nice slide fit into the case after this work so I cleaned it all perfectly with brake cleaner and fitted the new parts with the minimum of Loctite engineering adhesive required to ensure a good bond and seal. I then "staked" the top of the new bore with a square tipped punch.

I proved each new one with the usual methods.

I did this at home with basic tools just a Makita battery drill and and good quality drill bits...however I am a time served mechanical engineer with 30 years plus experience of metal and machining. I'm not sure alloy cases would be so "friendly" to work since it may be harder to follow the alloy squirter body with the drill. I would consider making a simple jig if it was a problem but getting the right angles could be troublesome.

For the record I tried drilling and tapping then slide hammer ( I even made a mini slide hammer ) but had no luck.

Hope this practical experience is some use..and offer a warning that new cases are expensive but temper that with the fact that if they are alloy a repair to an over drilled hole may not be so much ...your choice.

regards.

andy

[VitoV]

Excellent post, Andy.

[Walt Fricke]

Andy

I found the hardest part was restaking (pressure cast aluminum case). I thought I had made a suitable punch, but wasn't satisfied with the result. At which point I regretted not using green Loctite sleeve retainer. So I added some more stakes.

Later a friend asked if I had tested the new squirters. No, why? Because he had found some which did not work, perhaps because staking distorted them. Oh, well I'll find out at first teardown. Hope it won't be for a burned piston.

This got me to thinking that, at least for a race motor you expect to rebuild every couple of years, there must be a better mousetrap to hold these things in.

What about overboring the outer little bit of the hole, and taping it. Then using a threaded collar (open in its middle) to hold them in? With a screwdriver slot, so it could be removed as needed?

The collar could maybe even stick up some over the web? In which case it could have a hex head?

[boyt911sc]

Originally Posted by Walt Fricke

Andy

I found the hardest part was restaking (pressure cast aluminum case). I thought I had made a suitable punch, but wasn't satisfied with the result. At which point I regretted not using green Loctite sleeve retainer. So I added some more stakes.

Later a friend asked if I had tested the new squirters. No, why? Because he had found some which did not work, perhaps because staking distorted them. Oh, well I'll find out at first teardown. Hope it won't be for a burned piston.

This got me to thinking that, at least for a race motor you expect to rebuild every couple of years, there must be a better mousetrap to hold these things in.

What about overboring the outer little bit of the hole, and taping it. Then using a threaded collar (open in its middle) to hold them in? With a screwdriver slot, so it could be removed as needed?

The collar could maybe even stick up some over the web? In which case it could have a hex head?

Walt,

I had similar experience when I found 2 of the 3 oil squirters for bank 1-2-3 to be defective (clogged). I spent several days using Seafoam and high pressure air to de-clog the two (2) squirters to no avail. It looked very intimidating drilling out aluminum squirters out and had to ask advise from Bruce A. and Mike B. (both from Southeastern). Advise was to drill it out and stake the edge of the hole to keep the squirter in place.

I couldn't make a good stake or close to what the factory had on the engine. Getting a decent stake on the metal was quite a challenge. However, pressure test showed all 6 squirters having nice spray patterns and holding up against pressure. Below is the picture of the clogged oil squirter with factory stake marks.





The aluminum oil squirters for 3.0 liter engines are 6 mm in diameter and less than 22 mm long. So selecting the right drill size is critical. I used a 5 mm drill bit to take the old squirters out. See picture of the extracted squirter and the new one.

Tony

[haasad]

All great points, I too worried about how good the staking might be but have absolute confidence in the Loctite anyway . I think it was 241 engineering adhesive but cannot remember. The surface area it is working over is massive compared to the negligible load imparted by the oil. Looking forward a different fixing method may be an option which may if neccesary allow routine replacement . It may be possible to fit a small grub screw into the web instead of a collar at the top ? Those who do this frequently may come up with something but the diameter must be sealed to the bore to prevent a loss of oil pressure methinks.

I have a 2.2 on the bench now which appears to have had squirters retro fitted they are all glued in with no evidence of stakiing . They all seem very secure and have cleary seen some time in the engine with no problem , they all washed clear though so I'm not replacing.

Comments about diffrent sizes are true there are diffrent types listed by porsche for various engines the key is get the right ones and then remove the old ones .

I wonder if any alternative manufactures are out there for the squirters since they are common in many other engines and the OEM ones are very expensive.

TTFN

andy

[fastfredracing]

Thanks for the reply's, and that was real helpful Andy. If anyone else has anything to add, I would love it!

[KTL]

Maybe ask Mike Bruns (MBruns here on Pelican) @ JB Racing if he's willing to share how he replaces the squirters. I know he does this as a service on customer engines.

[neilca]

Since we are talking about piston squirters, has anyone drilled out a standard squirter to a 2mm turbo size? Not drill out to replace the squirter but just step up the exit hole.

[fastfredracing]

Finally made some headway today. Got all 6 squirters out of the case, new ones in, and staked back into case. I figured I would share how I did it, if it can be of any help to others out there. Although I was uncomfortable going at my case with a hand drill, it was actually pretty easy, and not too dangerous if you are not hamfisted about it.
First off, I delicately dremeled off the bulge from the stake into the squirter bore. I went easy, and kept checking with a magnifying glass . Next, I drilled out the top of the squirter with a 5/32" drill bit. Only drill down deep enough to get through the top of the squirter, and get the spring out. I was real careful here , I did not want to hit the spring with the drill bit, and break it off in there. That would be a mess. After you have drilled out the top, fish out the spring, and ball. A few of my balls were still stuck, and took a bunch of air pressure, and coaxing with a wire to get them out. Once you have the spring and ball out, I drilled down the rest of the way through the squirter. I then cleaned out all the chips, and ran a 5x80 tap down through the squirter. I was also careful with the tap, breaking off a drill bit , or tap would be just about the worst thing you could do here. The nozzles are soft alum, and drill easily, and tap easily also.
I then cobbled up a slide hammer with a 5 mm screw. I threaded the slide hammer/screw into the piston squirter bore. I threaded it all the way down , there are not many threads to grab onto, down in the bottom, so you want to make sure you are engaged as far in as you can be.
I then gently heated the case with the mapp gas torch. I watched it with a heat gun, and only went to about 120deg. It was early, and cold in the shop, and the case was only about 50 deg. at this point. A few gentle taps with the slide hammer, and they walked right up out.



At this point, I dressed the top of the bore, and made sure the new squirters would slide right in. I made sure to clean the squirter bore with brake clean, and q tips, and then the case went back to the tank for a good rinse and re clean of all passages . Install was easy peasy. I made a quick install tool out of one of the old squirters, and a long screw. I lightly coated the squirter in locktite 241, making sure there was no excess that could get under the squirter, and gently tapped them down in. Although the new nozzles were the same length, they had more of a chamfer on the bottom, and did not sit down as far. I then used a small chisel to re-stake at the factory spots, and added 3 more new stakes just for good measure. I gave the locktite a few hours to cure, and checked all 6 squirters. All opnened at low pressure, had a nice spray, and no more dripping out of any. Here is what it looked like after I was done

Have everything all layed out and ready, and can now seal up the case in the morning.

[neilca]

Nicely done,

Thanks for documenting the procedure also. I know it will help someone in the future.

[lindy 911]

Fastfred,

Are the through bolt holes chamfered on both sides of your case?