Intake manifold

[Brian French]

has anyone ever seen anything like this bolt before?

If so, what was it used for?

i replaced the intake manifold because the bolt had only 1 1/2 threads, and it created a serious vacuum leak.

Thank You;

Brian French

[tbirdtbird]

someone wanted some type of vacuum accessory in a bad way. The bolt was an attempt to block off the hole

[dmdeaton]

Might be taper pipe tapped. Try a pipe plug, wont get any points, might save the manifold.

[DaWizard]

Well, that is the same fix as putting a 3/8-24 bolt in the oil pump pressure hole. What you have there is a 1/8 pipe thread, and it just so happens, a 3/8-24 thread will start into it, BUT like you said, it won't seal on a tapered thread. So, pull the bolt OUT and get a small pipe plug and use that to fill the hole with a bit of high temp sealer, NOT Teflon tape!! It could have been used for an external vacuum gauge OR the MMO auto-oiler.

[tbirdtbird]

we do not know if it is NPT or machine thread. Some farmer type dude drilled it so all bets are off. There isn't supposed to be a hole there at all. I got the impression he already replaced the manifold

[DaWizard]

Exactly, that is why I suggested a pipe thread to seal off the hole where the straight thread didn't.

[Brian French]

Thank you, I think I understand now.

It is not a tapered pipe thread, so if I can, I might sandblast the manifold and a short sliver of the bolt, and silver braze it shut, and sand it flush. Should be good to go after that.

Thank you all, for your comments.

Thank You;

Brian French

[Brian French]

Now I’m wondering if the intake manifold had a vacuum gauge in that threaded port.

I saw this picture on MAFCA, Facebook post.

Thank You;

Brian French

[Tom Wesenberg]

I usually see a wolf whistle in an added intake hole. Too bad they do that because a brass tee would have worked just as well.

[plyfor]

hole for vacuum gauge to tune or permanent gauge per Brian has my vote!

[tbirdtbird]

In that pic i think the vacuum gauge is in the OEM port

[Tom Wesenberg]

Now I’m wondering if the intake manifold had a vacuum gauge in that threaded port.

I saw this picture on MAFCA, Facebook post.

Thank You;

Brian French

That's a cool fan belt, but with all those segments, it will cause wind resistance and slow the engine. LOL

Years ago my dad had a segmented belt like that on his bench grinder. I wanted one for my old motorbike, but they are quite expensive, even at Harbor Freight.

[Brian French]

Tom:

I actually use that type of belts on my table saw. They reduce vibration because the belt does not learn the rest position on the pulleys. It will result with a much finer finish cut.

All The Best;

Brian French

[tbirdtbird]

Brian, I find this very intriguing.
Can you elaborate on what you mean by the 'rest position'
Do you find it reduces vibration on your A? Certainly there are plenty of sources of this famous A vibration

[Brian French]

Tbirdbird:

i use a standard belt on the Model A.

The V belt on the table saw, or plainer or jointer, will conform to the pully diameter when sitting for a period of time. Typically when you shut off the machine the belt is warm, and cools into the shape where it stops. So..when you go to use the machine again, it will vibrate some, until the belt heats up, and then it will mostly smooth out.

The link belt does not achieve that memory like a solid belt, therefore when it starts up, it runs quite smooth.

I learned this this from a woodworking class, many years ago.

All The Best;

Brian French