EGR blanking plugs

[Alan L]

Anyone cracked the answer to stopping EGR blanking plugs coming out of the head?
I am using brass (tapered I think) 914 plugs. I believe they belong to the 914 brake system.
Every now and then, just when I think the problem has gone away, one blows out - comes loose and disappears.
I am guessing there is no loctite gunk that can deal with the CHTs so am thinking of tie wiring them. That will probably mean drilling a hole in the cooling fins on the head - which may be difficult in the car. I don't plan tearing the heads off to fix this. But would contemplate such a fix at some point when I have the heads off. Right now, hoping for another solution.
Thanks
Alan

[Bucketlist]

Alan,
Its been a while since I had a problem with mine so maybe I have a cure. I put a little bit of JB weld on the threads when I had them out about 4 years ago and they haven't been a problem since. I don't know how much trouble they would be to remove now.

[dannobee]

The proper way to safety wire would be to wire all three together. (Those are air injection plugs, not EGR plugs, which are entirely different)

SAFETYMETHODS

[Alan L]

OK, I will try some JB weld - the universal fixit. If that don't work, I will try and wire them. The system in the link by dannobee looks ideal - but implementing it may be a challenge. That would def be problem solved tho.
Thx
Alan

[Bucketlist]

Originally Posted by dannobee

The proper way to safety wire would be to wire all three together. (Those are air injection plugs, not EGR plugs, which are entirely different)

SAFETYMETHODS

Brings back memories from the '60s laying under a T-37 working midnight shift safety wiring fuel pump bolts in the rain, snow, wind, being visited by west Texas scorpions, tarantulas and other critters. I got pretty fast at that job.

If you could find pre-drilled plugs and safety wire pliers it would help. JB weld until it fails. I don't race mine so there's that....

[flightlead404]

Originally Posted by Alan L

Anyone cracked the answer to stopping EGR blanking plugs coming out of the head?
Alan

safety wire

[bleachii]

I left my air injector spider on the car even though I no longer have the EGR after going with the euro exhaust on my '79. Does everyone else remove the injector and replace with plugs? Any issues with leaving the injector on the car? My car is otherwise stock other than replacing the thermal reactors with the euro exhaust.

[Alan L]

So I am going to have a crack at wiring them. They are recessed - so really difficult.
What I am thinking is getting some M10 bolts with a part unthreaded shank. Cut thread to right length. The shank needs to be about 30mm, to protrude from the head enough to run the wire thru.
Thats the current plan anyway. It is really inconvenient when they blow one out on the track.
Thinking of using some 0.8 stainless MIG wire - since I don't have any of the proper stuff.
Thanks
Alan

[reclino]

I think part of the problem is the difference in CTE between a steel or brass plug and aluminum head. I have a theory that aluminum plugs made of the same alloy as the head or an alloy with the same CTE should stay in place. However I can not find the CTE.of Y alloy,.or RR350 alloy.

[Alan L]

Yes - the temps are extreme so these small things probably matter.
Just tried fitting my modded bolt to the #3 head. Won't fit in - the head on the bolt hits the fins on the cyl head. It might work if I machine the hex head down on each bolt.
So I have wired a plug in place as best I can.
Some proper Al welding (as compared to B Weld) may be the final answer. But getting to #3 may not be easy (unless I remove the X over pipe).
Alan

[Alan L]

OK - hoping this will work. Had to use cap screws in the end - the hex heads on the bolts did not have enough clearance. Thought the cap screws would be harder grade of steel to drill, but they went OK.
Tried to change the title of the thread from EGR to air injection in case someone wants to search the topic. But it would not let me.
Alan

[Bucketlist]

This looks like it may work but I always thought the twisted wire between the bolts was what kept the tension on them and kept them tight. Without the twist wont the bolts just get loose but not fall out? This is where a good set of safety wire pliers are necessary.

[Alan L]

Yeah, I don't have the proper pliers. But have routed the wire so that if they want to undo they are in fact tightening the wire more. I have thought how I can tidy a couple of loose ends - stick a nail between the end loops and rotate tight. Not easy getting in there.
Another advantage of the bolts is there is 2-3 x the thread engagement compared to the plugs. I cut the thread length on the bolts to match the thread length in the head. They are tight.
Fingers crossed.
Alan

[TurboKraft]

Alan -- If we have tired threads in heads, we use a hex head fastener (like in your first photos), cross drill them, and also drill a hole through one head fin to wire the fastener to. Safety wire pliers are really inexpensive now, but this can be done by hand.

[Alan L]

Thanks Chris - I will revert to that if this does not work. But I am reasonably confident with this fix. I have tidied up the loose ends on the wires and all is tight. Fingers crossed.
FWIW, this car has been on the track now for about 9 yrs, and just clocked it quickest time ever a week ago. And the driver is heading for his 70th b/day in a month.
We are growing old disgracefully together.
Regards
Alan

[infraredcalvin]

Just figured I’d have them welded up when sending heads for rebuild…. hopefully soon….

[Alan L]

Thats what I would do if the heads were off and I knew I had no need for the air injection at some later point.
I wondered if I could do it with them in place - possibly. But chose this option first.
Alan

[David]

Here's an old picture of what I did: I tapped the hole all the way through the exhaust port and made threaded aluminum plugs to go in. Then blended the plug smooth to the port.



NOTE: this is my 10,000th post (In case I ever wonder what my 10,000th post was )

[Alan L]

Now that is nice - a proper job.
Alan