Plug size for air injection? (1 Viewer)

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Aug 11, 2005
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Gig Harbor, WA
Can anyone please tell me the correct size/threads, etc for 1978 FJ40 2F engine? The air rail is coming off this weekend for a set of Downey headers (without the EGR fitting), and I'd like to source appropriate plugs beforehand. Thanks.

Looks like a search reveals 1/4 NPT?? So...never mind!! Thanks anyway...
 
I believe it is 1/4" pipe thread.
GL

Ed
 
Or you can just make some. I did that once and made them flush to the head with screwdriver slots. Disapeared under a coat of black paint.
 
1/4 NPT is actually close, but not quite there...it's a little small. The actual size and pitch is M14 x 1.5 IIRC, now I can't find the post I made where I confirmed that...I still had exhaust leaking out with the 1/4 NPT. If you take it in and compare the threads you'll find it. Try to find a metric supply company near you. :popcorn:
 
If I Recall Correctly
 
I'm glad I can finally contribute something useful :D
 
subzali said:
M14 x 1.5

I searched for a LONG time both at local 'got everything' bolt houses and online sources and never was able to find a suitable plug with the correct threads. I wanted a recessed allen head plug - not a big bolt head sticking out. AFAIK, no such animal exists, although the 3FE factory plug sounds promising.

The brass 1/4" NPT plugs can be had at any hardware store and they seal fine in my experience. A little high-temp sealant or loctite probably isn't a bad idea, though.
 
I just had the Man-A-Fre 2-piece headers put on my '78 FJ40 and when the shop was doing the work they found my EGR and Air injection were toast. (oh gee, too bad.) It was recommended that i use 1/4" brass allen head pipe plugs to plug up the air injection ports. I found them on-line at:http://www.kimcoweb.com.

the question now is, what sort of plug do i use to fill the pipe the comes off the carb where the EGR attached. Does this need to be heat resistant? Seems not as the exhaust manifold is now divorced from the Intake.

the other issue is finding a nice way to cap the pipe that comes off the air cleaner top that fed air to the air pump. Specter shows one that was apparently available for Canada, but is discontinued. i was just going to use a big black rubber stopper and jam it in there with a bead of weather strip cement around it.

any thoughts?

btw, i LOVE the way i can hear the CO2 molecules singing in the headers as i accelerate. my shop acknowledged that the Man-A-Fre tuned 2-piece headers are the nicest they've installed and they do a lot of Cruiser work.
 
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oh and i've owned my truck since February of '82. yeah, i'm a lifer.

did a 1st gen suspension correction 15 years ago as well as Canadian Vac. Adv. Dist and Carb. otherwise pretty much stock, though i made the mistake of a Mallotte Fiberglass tub and front end parts. I'm now back to an entirely OEM steel front end, and just replaced my badly rotted driver's door with a NOS one. sweet. Got a NOS left Ambulance door that will go on soon. Still looking for RT Ambulance and passenger doors in good consdition.

i laugh and say that at some point, even though the VIN is the same, every part on the vehicle will eventually turn over so it will be like building a new city on top of old.

yep, there ya go. bury me in my Cruiser.
 
Air filter hole

I used an aluminum An plug for plugging the hole coming from the air filter. I RTV'd it in place and painted it black. seems to work pretty well
cap.jpg
 
e rock said:
I searched for a LONG time both at local 'got everything' bolt houses and online sources and never was able to find a suitable plug with the correct threads. I wanted a recessed allen head plug

my local ACE hardware has them,,, at least they did when i bought 6
 
Colorado Boy-74-FJ40 said:
I used an aluminum An plug for plugging the hole coming from the air filter. I RTV'd it in place and painted it black. seems to work pretty well

my eyes hurt when I look at that picture....

bk
 
sorry to have hijacked this thread with the puzzling about other plugs. i posted the full deets on where to get brass 1/4" plugs in a seperate thread.

that said, yeah i'm havin a hard time seeing what's going on in the shot above. for the air cleaner hole i just jammed a black rubber stopper in and that should do it.

now to figure out what to plug the EGR port on my carb with.
 

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