Oil (piston) squirter......

[boyt911sc]

I'm in the middle of an engine rebuild and would like to know or understand how the oil (piston) squirter/s work. Attempted several times to trace and follow how the oil is delivered to the squirter/s but to no avail. The engine has undergone a catastrophic failure before that no one has determined the exact cause even after posting this picture in a previous post. BTW, bought this running engine with broken head studs from another Pelicanite hoping for a top end work only.


I would like to know and understand how the oil flows to the squirter/s. How is oil delivered to these piston squirter/s?. Being able to know or determine that these squirters work would give me some piece of mind that I need to finish this project.




I would appreciate very much if someone would try to help me understand by explaining how the oil is delivered to these locations (squirters). Thanks.

Tony

[tadd]

The hole the squirters reside in is drilled right into the main galley in each case half. The squirters themselves have a small ball that is spring loaded as a low pressure check valve. No need for them to be open at idle.

The main galley feeds the main bearings.

t

[cgarr]

Your second picture shows the passage to the squirter. You can put some pressure on that hole and it should open at about 20 or so pounds. They are just a ball and spring. You should not be able to back feed them, if you can then they are shot.

[vmisquez]

Tony,

Oil pressure within the throughbolt holes feeds these squirters. Stomski Racing makes a cool little tool for sealing the passages to clean and test the squirters. Others use screwdriver/rubber or wooden dowels to seal the passages. I have also tried these other methods but favor the tool from Stomski Racing.

You should also read and re-read Waynes book on 911 engine building. the Bruce Anderson book is also help full.

Good luck with the rebuild

[PFM]

Plus one for the Stomski Racing tool for oil squirters and piston wire lock tool!!!

PFM

[Flat6pac]

What do your rod bearings look like? I was under the impression the squirters were for cooling to back side of the pistons and the splash effect of the oil to the rods lubing the walls of the cylinders.
Bruce

[boyt911sc]

Originally Posted by Flat6pac

What do your rod bearings look like? I was under the impression the squirters were for cooling to back side of the pistons and the splash effect of the oil to the rods lubing the walls of the cylinders.
Bruce

Bruce,

This was how the old pistons looked like when I tore the motor up. The engine was running with a broken head stud when I bought it from a fellow Pelicanite. I was expecting to do just the top end but to my surprise, the engine was in such a bad condition that it needed a complete overhaul.

Up to this point, nobody could give me a definite answer as to what could have caused the pistons to get to this horrible condition. The cylinders were not as badly scuffed as the pistons. So I'm paying more attention to the internal oil circulation for this particular motor which had a bad history. The main bearings, crankshaft, connecting rods, and other internal parts are in good condition except for the pistons and cylinders.

Tony

[cgarr]

Did they use the wrong pistons? not iron coated with Alusil cylinders?

[brads911sc]

take a piston out and type the part number. also type the part number of the cylinder...

[lindy 911]

To me it looks like the motor tried to seize. Piston squirters (or lack of) did not cause this in my opinion. It looks as though the induction leaned out somehow and the motor got hot and the pistons grew bigger than the cylinders.

Check my rebuild thread and see how we checked the operation of the squirters. Not hard to do and a little Seafoam injector cleaner will do wonders. I tried carb cleaner and the like to no avail until I found out about Seafoam; a few drops, wait 10 minutes, apply some air pressure and poof they open right up and blew a nice spray.


Lindy

[gsjohnson]

Looks like after market pistons that swelled in the cylinder too much, which is typical when using after market pistons...and I agree, it does look like it was trying to seize as a result. Either that or the engine was running too hot. Doesn't look like a oil squirter problem to me.

[lindy 911]

To me these look like stock CIS pistons based on the dome shape which are only available from Mahle or KS. I definitely think the motor leaned out to the point of seizure.

In the pictures I posted, the top pic shows a rubber hose tool I made in the through bolt bore blocking the oil inlet from the bore to both the main bearing and the squirter. The hose is 3/8 fuel line with a 8mm stud to fatten it up a bit. The through bolt bore narrows at the point where the oil passages are for the main and squirter. The hose is tapered at the end to wedge into place.

Once the hose is in place, a couple of drops of Seafoam are placed in the main oiler and allowed to seep down to the squirter and sit for about fifteen minutes. Then pressured air is applied through the main oiler and viola.

[TdiRacing]

Make sure the squirters seal both ways. Meaning spray, then seal back up. Just leaned this and ended up replacing all of mine because a few would spray but not seal. Not an expert but was told that this will cause low oil pressure at low rpm, and idle. Makes sense now. I did have oil pressure issues first time around. There is a little ball and spring in there. Allows it to open at higher rpm and spray. Closes at low rpms.

[billjam]

This might help as well ...