Newbie with a question - what is this plug on my intake manifold? (1 Viewer)

[jmcm]

Hi Everyone!

I'm new to the boards - been lurking for a few years on google and decided I'd finally join. I'm located outside of Houston and mostly drive my cruiser around town for now, haven't taken her offroad.

Got a question that I can't seem to find the answer to in the manuals - what is this black bolt in my intake manifold? It looks like it has three holes and smoke testing indicates that they're allowing air into the manifold. I should have circled it, it's the black bolt about a half inch down the photo from the carb.

I've got a whistle after I warm up. Any chance it's this thing?

jmcm

 

[1911]

Welcome to Mud!

You've posted in the wrong sub-forum, maybe a moderator can move it for you - should be in the 40 or 60 sub-forum, since you have a 2F engine.

But to answer your question, that is what Toyota calls a "gas filter" (Engrish) in the Emission Control Repair Manual . It is a vacuum source for some of the emissions control equipment, and more importantly for the vacuum-powered vent system for the distributor cap.

It looks like your 2F has been de-smogged, so whoever did it broke off the three little vacuum line nipples that should be on top of it. If they're just broken off and not capped, then yes it would be a small vacuum leak. To find a vacuum leak, spray some carb cleaner around the suspected leak with the engine running, and if the idle rpm changes then you have found a leak.

 

[jmcm]

Thank you! And thank you for correcting me on the sub-forum. I'll try to get in touch with the moderators to move the thread.

On the bolt topic, is there any issue with removing this bolt and plugging the hole with a steel bolt to fix the vacuum leak?

 

[65swb45]

Thank you! And thank you for correcting me on the sub-forum. I'll try to get in touch with the moderators to move the thread.

On the bolt topic, is there any issue with removing this bolt and plugging the hole with a steel bolt to fix the vacuum leak?

No.

 

[shawnfj40]

Use a plug and not a bolt. The threads are different.

 

[jmcm]

Thanks guys.

Any reason I'd want to use a steel vs aluminum vs zinc finished plug? My metallurgy isn't very strong.

I've heard steel to aluminum can seize and the engine is cast iron, so that would make me guess I want to avoid aluminum.

 

[Poser]

You will likely not ever want to/have to remove the plug after it is installed; any of the finishes listed will work fine.

1/8" BSPT is the thread, iirc.

 

[shawnfj40]

Brass gets along with everything if your concerned.

 

[Spike Strip]

Good dollop of Anti-seize or high-moly grease on the plug if you plan to remove, later.

 

[jmcm]

Thanks guys.

Looks like these plugs are pretty hard to find. Lot of 1/8" plugs available but BSPT not so much.

Appreciate the help.

 

[Spike Strip]

1/8" Male BSPT Steel Socket Head Pipe Plug | Fastenal

Pair 1/8" BSP BSPT Pipe Thread Allen Head Plug Chrome Plated Brass +W1 | eBay

Literally 2 mins of Googling...

 

[71FFJ40]

Any Hydraulic hose supply house will have 1/8 bspt plugs.There are several hydraulic hose suppliers near you as per Google

 

[jmcm]

You're the man. I found some online but couldn't find anything in person, which I prefer in the event it doesn't fit.

Will check hydraulic hose suppliers.