3FE "Magic Screw" (1 Viewer)

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remac226

remac226

Joined
Apr 13, 2007
Threads
65
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Location
Columbia, SC
I found this over on the 60 forum:

https://forum.ih8mud.com/60-series-wagons/220869-what-deuce-thing.html

I still am not clear on what it does but I checked mine yesterday and the screw was lying on top under the cap. The threads were all messed up so I went to lowes and bought a M3 x .5 x 10 screw (hardware section) and a new o-ring (plumbing section) and installed it. I did notice that the idle smoothed out some immediately. Not that is wasn’t before but smoother. As far as a power increase I do not notice much if anything. I have not driven far enough to comment on the mileage increase that is claimed but we will see. If I can go from 10-12 to around 15 it will be the best $3.00 ever spent. I will update any increases once I have driven some miles.
 
do not get your hopes up. i have tried about every free or cheap mod on here, the ones that helped the most were timing advance and desmog, the others might of helped a little but those 2 made the biggest diff, timing being the biggest.cryo sparkplugs helped as well.
 
If you read the entire thread you will learn that it's the fuel pulsation damper. If the screw has backed out, then the unit needs to be replaced with a new OEM one as they are calibrated from the factory. Simply replacing and tightning the screw may yeild some results, but the pressure in the fuel rail will be effected.
Parts like this should be replaced with new, not repaired. If your $3 fix leaks you'll be dumping fuel on your manifold.
 
Jon I am with you and am going to look into a new one. With that said, I do not see why it would start leaking with the screw back in it since it was not leaking with the screw out of it?
 
The screw limits the flexing of the internal diaphragm of the FPD. If the screw has been out of place for some time it is possible that the diaphragm is compromised. Add that to the fact that i's likely 20 years old and lives on a pressurized fuel line, I'd vote for replacement.
 
All good stuff. I hope it works out for you.
I have a new FPR and FPD along with plugs, cap and rotor on the way to me this week. I'm hoping this solves my hard starting issues and brings back some power.
 
Fuel pressure regulator. The FPR and the FPD control the fuel pressure in the fuel rail that feeds the injectors. If fuel pressure gets too high injectors start to leak and seals can fail.

The FPR controlls the overall pressure and the damper helps to equalize or absorb the transients caused by groups of injectors being pulsed.
 
Would accidentally turning the screw on the FPD cause some hurt? I was a dummy and turned it a few times while performing the headjob. I set the screw back as best as I could remember, but I never backed it out or turned it down completely. I have been trying to figure out my idle issue lately where I dip low on the tach. I didnt remember my screw up until I read this post.
 
Well, I removed the plastic cap and there the screw was just laying in there with a rubber o-ring on it. I think I'm with Jon to replace the unit but why not try to screw it down a bit. Anyway, looks like the threads on the screw are compromised I'm planning on getting another and report back.
From the original 60 series thread, the screw is a m3, .50 pitch and 6mm long. Going to ACE to spend a quarter. Update, it's not 6mm long more like 8 to 10mm (actually 8.5mm). Bought the 8mm, seemed too short, couldn't find any threads and dropped it down the back of the engine. Can't find it and will try a 10mm long with a flat m3 fender washer and a new nitrile o-ring tomorrow.
 
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I could not get the 6 to grab so I used the 10 and it worked fine as far as I can tell. Jon is right and the best thing to do is replace the thing. That is on my list but it was not leaking before or now but I am going to keep a close eye on it. As far as proper adjustment goes, I have no idea. I would say try adjusting it and see if it makes a difference for you. From what I read the new ones come with a rivit instead of a screw. Also seen to be a real PITA to change out because of where it is.
 
The 6 just turned and turned and never grabed anything. I did put blue locktite on the threads. I slowly screwed it in until it was snug. Once it stopped the screw did not protrude out of the housing. In thinking about it the threads on the original screw are only about a third of the way up it. I bet that was like that so when it stopped turning it was "in adjustment". I may have it too tight. On the other hand, I dont know if the screw will screw in futher than the original would anyway. I think I am going to lossen mine and play with it and see if I see any difference. Did you get the 6 to grab?
 
remac226 said:
The 6 just turned and turned and never grabed anything. I did put blue locktite on the threads. I slowly screwed it in until it was snug. Once it stopped the screw did not protrude out of the housing. In thinking about it the threads on the original screw are only about a third of the way up it. I bet that was like that so when it stopped turning it was "in adjustment". I may have it too tight. On the other hand, I dont know if the screw will screw in futher than the original would anyway. I think I am going to lossen mine and play with it and see if I see any difference. Did you get the 6 to grab?
Click to expand...

I couldn't even get the 8mm to grab. The stupid thing was I bought it in stainless steel which could not be held by my magnetic screwdriver so it got lost. Anyway tonight I put a 10mm in with a m3 fender washer and a nitrile o-ring. I tightened it until it became very snug. Enough to make the o-ring seat. Used blue loctite on the screw and a drop of super glue on the head/washer to help hold it in place. No leaks, idles normal and performance is unknown right now. Need to check fuel mileage and report back. I would be very surprised if a "magic screw" helps my fuel mileage. We'll see. I really wanted to post that I got my first 2nd gear scratch and I did my first 4 wheel burnout but not.
 
Anyone have photos of the screw in question and these parts to post up?
 
My threads were also toast. picked up my new part today, seems to have really smoothed out my idle, and maybe even picked it up a little.
Gonna road test shortly..
screw [1024x768].jpg
 
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