block/deck oil restrictor

[iTurbo]

Just how important is it to have the block/deck oil restrictor in place?

Right now I'm just about to put the head on an '87 Turbo II motor I'm building. It doesn't have a restrictor at all. I ran it this way for a long time in my Shelby Lancer with no issues that I could tell at all. I didn't even know it wasn't there until tear-down; although I will say that many years after installing it, I did toast a rod bearing racing a VW Golf GTI. There was also some 'chipping' of the main bearings. I probably over revved it.

I've since rebuilt it all, but finding one of these restrictors is proving to be very hard, since they are NS1.

I did find a thread about a guy that made one out of a 9mm casing, but when I tried it just didn't quite have enough outside diameter and it would just fall through the hole. Any ideas here?

[going4speed]

Does Martin have any at arizonaparts?
Believe the restriction from that part keeps oil pressure in the bottom end and stops all the oil from pumping out of the pan into the head.

[johnl]

Won't any chunk of rod, of the same length and OD and drilled to the correct ID, work?

[iTurbo]

Won't any chunk of rod, of the same length and OD and drilled to the correct ID, work?

I got lucky on one of the last engines I built (a TI), and found a guy that had the stock part. I'm starting to think maybe just a small pipe plug with the proper size hole drilled and chamfered carefully should do it. Or maybe if the 9mm casing could be resized just slightly.

[iTurbo]

I talked to my Dad tonight for a while about this. He has much experience in reloading ammo. He got his Hornady book out and the 9mm round is .380" diameter. It is just slightly too small to fit. The .380 ACP round I have is even smaller so that is a no-go. He says my best bet is to try a 30-30 next. It necks down from the mouth to head, but at least I can put it in the hole and get an accurate measurement of the oiling hole with it (measuring where brass contacts the hole and measuring the score line with a micrometer). I'm guessing it's right around .400".

Does anybody know the *inside* diameter of the oiling hole? The primer pocket of these rounds is obviously larger (about 1/8"), but the firing hole behind them might be very close. Brass seems like an ideal material here.

[ajakeski]

I have a junk block on the engine stand. I can measure the ID of the bore and the OD of the restrictor.

[iTurbo]

I have a junk block on the engine stand. I can measure the ID of the bore and the OD of the restrictor.

That would be awesome. And if you can get a close approximation of the actual oiling hole diameter with a drill bit or something that would also be great.

[raccoon]

Whats this thing even look like? Im redoing my first engine I built for my acclaim years back and low and behold, no restrictor.
I was nothing but abusive to this poor 2.5 for 150k kilometers, till it started to have bad blow by. didn't even have a lubrication failure.

maybe just maybe its redundant.

Still, knowing what I know now, I wont be able to reassemble this thing without it.

[ajakeski]

The oil gallery bore ID in the block measured .400 inch. (13/32 inch)

The restrictor is tapered with the widest point of its OD being .460 inch. (3/64 inch)

The ID of the bore of the oil restriction is about .142 inch. (9/64 inch)

The restrictor is an interferance fit and compresses slightly when pressed in the oil gallery.

The fractional equivalents posted above are approximates taken from an engineering chart.

[4 l-bodies]

Jeremy,
.125 to .150 hole is about what you are looking for 8v applications. The factory varied the size throughout the years. 16V applications were smaller yet. If you find some used ones you can braze the hole shut and re-drill, as sometimes removing them makes hole a bit bigger. I use to to buy them at Mopar all the time. Not available anymore through Vintage Parts?
Todd

[ajakeski]

I would think you could tap the oil gallery and thread a set screw in there. Drill what ever size hole you like in the set screw.

The 0.40 bore is just under 10mm.

[iTurbo]

Thanks for the help and information Andy and all. Very much appreciated and I'll let you know what I end up doing for a solution.

Hopefully I can make my own, since they aren't available at the dealership and I can see this happening again on future builds. I haven't tried Marty or looked into Vintage parts yet though.

[Vigo]

Last one i did i just tapped it for 1/8npt (which is 0.407) and then drilled the npt plug with the biggest drill bit i had that would fit through the restrictor hole in another block that still had the restrictor. I didn't want to mess with trying to remove and reinstall it when the real problem was needing more of them than i had, so i just made one.

[83scamp]

Last one i did i just tapped it for 1/8npt (which is 0.407) and then drilled the npt plug with the biggest drill bit i had that would fit through the restrictor hole in another block that still had the restrictor. I didn't want to mess with trying to remove and reinstall it when the real problem was needing more of them than i had, so i just made one.

+1.


That's what they did in the old days. Especially when they were running the IMSA motors. The pressed in plugs would work loose in the high rpm environment. Plus they wanted less oil to the head anyways because of the mechanical cams, so they made their own thread in plugs with smaller restrictors...

[iTurbo]

+1.


That's what they did in the old days. Especially when they were running the IMSA motors. The pressed in plugs would work loose in the high rpm environment. Plus they wanted less oil to the head anyways because of the mechanical cams, so they made their own thread in plugs with smaller restrictors...

I have thought about this, and also trying to get a ~.400 brass plug to press in and drilling it to match. I'm not wanting to stick a tap in there at this point because the short block is already built. I'm sure I would do everything in my power to get the iron shavings out, but I'd rather avoid it. With a good press-fit, I doubt the restrictor would move, and with the cylinder head on, it seems like it would just stop at the HG anyway...

I plan to put this motor in with a FWDP S2 roller cam. Seems like that would need even less oiling than an old slider considering there won't be cam oil squirters in the caps.

....this would so be a non-issue if I could only buy like 4 of them at the dealer. If I'm not mistaken, even the later 2.0/2.4 used these, so I'm surprised they are no longer available. I'm not sure how you'd go about removing one after the fact, unless you had some sort of super special slide hammer.

[Vigo]

like it would just stop at the HG anyway...

The headgasket doesnt stop it and the head has a pretty large recess above it so if it WERE to pop up i think it would stop restricting oil at all and then you'd probably run into oil starvation issues at sustained high rpm.

The NPT plug i used actually had a tall square 'head' for tightening that stuck well up above the block. I actually drilled the orifice in it sideways so that if it backed out enough to hit the head it wouldnt block the oil hole.

[iTurbo]

I worry a bit about the length of the oil passage. It seems to me a .125-.150 oil passage (like Todd mentioned) would be more restrictive through a longer passage such as that drilled through a 1/8" NPT pipe plug (~1/2" thick) versus the stock part or a shell casing or a press in plug (thin).

As long as a decent press-fit is attained (like with the stock part), I can't see it getting dislodged or even moving at all by oil pressure alone. Seems to me this restrictor was incorporated by the factory after about '86 or so to better balance the oil pressure/volume to the block and top end to prevent the kind of failure I've already had.

[going4speed]

the pressure drop over such a short distance is negligible. However if this is the concern enlarge the drill hole slightly to over come the pressure drop. The factory used all manor of sizes for that hole size anyway.:)

[supercrackerbox]

I've got a few handfuls of spent .40 cal brass if that helps . . .

[going4speed]

40 cal ftw

[supercrackerbox]

40 cal ftw

Darn tootin'

[mech1nxh]

With respects to All,
The 'restrictor' is a simple CORE PLUG... Picture oil galley plugs that need to be removed
& reinstalled after proper block prep on some domestic V/8's.
The sizes & materials available are into the hundreds ( if not thousands).

No need to 'modify' the block/ head --- I am a Puritan TurboMopar Geek ---
I.e, cheap is good !!!

[iTurbo]

With respects to All,
The 'restrictor' is a simple CORE PLUG... Picture oil galley plugs that need to be removed
& reinstalled after proper block prep on some domestic V/8's.
The sizes & materials available are into the hundreds ( if not thousands).

No need to 'modify' the block/ head --- I am a Puritan TurboMopar Geek ---
I.e, cheap is good !!!

Actually, it's not. It actually is quite long ) ~1" and looks somewhat like a hollow bullet (the lead part). It tapers at one end. Not a simple core plug though a core plug could work.

I will try the 40 cal next.

[iTurbo]

So far I haven't been able to find a 40 cal shell casing. Still looking though.

Has anybody out there successfully removed one of these restrictors from a block, and if so, what tool did you use?


EDIT: My friend at NAPA found me a 7/16" steel plug (not brass unfortunately, but .4375" which is the closest I can find), and my step dad is letting me borrow his 40 cal tomorrow. He doesn't have any empty casings so it looks like I'll just go fire off a few rounds tomorrow on BLM land and collect the shells..

[black86glhs]

I have used a long screw threaded into the restrictor and 2 pry bars to pop it out of the block.

[iTurbo]

I have used a long screw threaded into the restrictor and 2 pry bars to pop it out of the block.

Thanks! I will give that a try. Unfortunately the only block I have lying around is an '89 2.5L TI, and I plan to build that soon too..

The closest thing I've found yet is here:

http://freezeplugfactory.com/expansion-plug-size-chart/

It's listed as part #104, it's 13/32"; 10.32 mm. That equates to a .406" plug. It's also brass which seems ideal.

[Dr. Johny Dodge]

could you not make one out of a piece of round bar stock with a hole drilled through the center ?

it could be made long enough to be stable once hammered into the passage

[iTurbo]

I've never had to use round bar stock for anything as far as the limited amount of fabrication work that I've had to do in the past (forgive me).

Would it be available in 13/32, 11mm, or something close to just over .400"?

If it were available in a diameter close to that, but only available in steel, it would be harder to work with (for me). I like the idea of using brass so that I could use a slightly oversize piece (like the brass core plug listed above) and use emery cloth to carefully sand down the outside diameter for a proper press-fit. Steel would be more difficult. This is why I'm seriously looking into a bullet casing (like the 40 cal) which seems to have worked for others in the past.

The passage is quite long, probably 3-4". The OEM piece was probably 1"-1.25" long. I will look into this option since I'm stuck finding a solution to this so I can finally bolt the cylinder head on!

If anybody has one of these lying around or in the Mopar bag I'd love to buy one. I'd love it even more to find a DIY solution because I have lots of engines to build. Some of the blocks I have just don't have one at all. I do NOT want a repeat of spinning rod bearings and chipped main bearings!

[supercrackerbox]

So far I haven't been able to find a 40 cal shell casing. Still looking though.

I could have mailed you some by now. :lol: PM me your address if you want.

[iTurbo]

I got the 40 cal shell casing to work tonight! After a little work it fits perfectly.

Basically I used a 1/16" pin punch to get the primer out, the skewered the shell through the primer hole with the pin punch and held it very lightly against the bench grinder to take down the outside diameter of the lower half of the shell (the side with the primer). This spun the shell casing very quickly like a lathe of sorts, and I was able to get the outside diameter ground down and still maintain roundness. The first time I tried, the shell casing broke in two when the brass got too thin about 1/2 way up the shell. To avoid this, I only ground the lower half of the shell (the primer end) just enough to get it started into the oiling hole in the block. I then ground two notches 1/2 way down the shell casing from the bullet end with a Dremel and cut-off wheel. This made it so I didn't have to grind the brass too thin (causing breakage) and also let the shell press in tight (by closing the notches together as it went in) I drilled out the primer firing hole to .125" After some wire wheeling and cleanup, I used a hammer and a very small deep socket to pound it just below the deck.

It took about 15 minutes to make, with the majority of that just carefully grinding and wire wheeling it clean for a good tight fit.

[Fuzz's '87 Shadow]

Big question on this subject...I've heard that the plug was a hit or miss on the motors. My 88 CSX-T didn't have one when we tore it down, so how important are these really? We just did an inframe on the motor and put everything together, but now this subject has got me wondering. Is it different if you use a roller versus a slider? Is it for racing application or general driving?

[83scamp]

Big question on this subject...I've heard that the plug was a hit or miss on the motors. My 88 CSX-T didn't have one when we tore it down, so how important are these really? We just did an inframe on the motor and put everything together, but now this subject has got me wondering. Is it different if you use a roller versus a slider? Is it for racing application or general driving?

They were put in at the factory. The orifice size varied over the years. I believe the slider cam motors had the larger orifices. According to Chrysler, it is needed. It prevents flooding the head with oil, and maintains priority oiling to the mains & rod bearings.

[iTurbo]

They were put in at the factory. The orifice size varied over the years. I believe the slider cam motors had the larger orifices. According to Chrysler, it is needed. It prevents flooding the head with oil, and maintains priority oiling to the mains & rod bearings.

This mirrors my somewhat anecdotal experience.

I've had two engines so far that I've found did not have the restrictor. One was an original 2.2L TI engine out of an '85 Shelby Charger, the other is a 2.2L TII engine that originally came from Mopar Performance R&D (I bought it from Dave Grove back in '99). This is the one I'm working on now.

The TII ran great for a long time, but I finally spun a rod bearing racing it. I didn't have any sort of oiling issues or oil out the PCV system or anything like that. After teardown, I found a couple of rod bearings that came out in many pieces and main bearings chipped (#5 especially). For that reason, (and what 83scamp described), I would not build another 2.2/2.5 without one. The '87 FSM clearly shows the restrictor in place in a technical diagram of the engine's oiling system. Hopefully having it in place will prevent future rod/main bearing premature failures.

[Vigo]

I think the simplest explanation is you don't need it for low rpm operation, but at sustained high rpm it keeps the engine from pumping all the oil into the head and starving the pickup.


So the way most people drive, they may never blow an engine because of it, but anyone who does sustained high rpms needs it and really everyone 'should' have it.

[supercrackerbox]

They were put in at the factory. The orifice size varied over the years. I believe the slider cam motors had the larger orifices. According to Chrysler, it is needed. It prevents flooding the head with oil, and maintains priority oiling to the mains & rod bearings.

According to one of my factory service manuals (either '88 or '91, can't remember right now), they were only put into the 2.5 engines, and NOT the 2.2 engines.

Either way, I've got them in both the Daytona (2.5) and the Charger (2.2).

[going4speed]

my omni 1986 has it.

[bamman]

Chrysler has been using a 0.125 inch oil restrictor in the 2.2, 2.5, 2.0, and 2.4 blocks from 1986 onward and the 1996+ 3.3 and 3.8 blocks, as mentioned in the FSM and in the parts manual.

1985 and before blocks used a different size oil restrictor.

[4 l-bodies]

Chrysler has been using a 0.125 inch oil restrictor in the 2.2, 2.5, 2.0, and 2.4 blocks from 1986 onward and the 1996+ 3.3 and 3.8 blocks, as mentioned in the FSM and in the parts manual.

1985 and before blocks used a different size oil restrictor.
Yeah that is what the FSM will tell you, but if you bought any oil restrictors from Mopar and measured them, you would find most of all the current ones were around .140" or larger. The last six or so I've bought were all well over .125", closer to .150 than .125.
Just measured a restrictor from a virgin 89 2.2 TII motor I pulled apart. #27 drill fits (.144") & #26 (.147") does not. This is typical and not out of the ordinary.
Todd

[Vigo]

Now i'm left to wonder if my early 3.8 is going to oil starve if i stay at high rpm long enough.

Ah well, it won't happen if i never drive it. :D

[DodgeZ]

I think Cindy has them. I found some oil plugs at oReillys drilled a hole and hammered it in.

I had a Lancer with oil pressure problems After it warmed up it couldn't hold oil pressure. As the RPMs went up the oil pressure went down.

I had short block built and was in process of installing it. Pulled the head and saw it was missing the restrictor. I rolled the dice added the restrictor and reinstalled the head. No more oil pressure problem.


In my review of the problem the I found on other motor types, is that aftermarket pumps evacuate the oil from the pan quicker. So on a stock pump you may get by with no restrictor. If you have a high volume pump you may end up sucking the pan dry.

[mech1nxh]

With Most Humble Respects Honored Posters---
The 'restrictor' , with its many varied orifice sizes was a 'band aid' to supply
oil to the aux shaft, & a casting dependent 'fix' ;) more to follow as the thread evolves.