85 Nissan 720 4x4 Weber Strainer inspection plug leak.

[Thomas Perkins]

Hi ya'll.The strainer inspection plug on my Weber just wants to leak.It is the big screw plug that holds the little fuel filter in.I even bought another plug,nothing wrong with the original one.I tried teflon tape and that didn't work.It is not a drip leak.No fuel stains on the intake but has stains running down the Weber.The little fuel filter is like new.You really can't see anything if you look at it from the front.But if you run your finger down the bottom of the plug,gas will be on my fingers.You can see the trail of the gas stains leaving from under the plug.The teflon taped worked for a very short time.When it leaks,it causes the idle speed to go up and down.This plug has always leaked and never thought it was the reason my idling was going up and down.So not long ago ,i used some valve cover black sealant around the bottom of the plug.But I didn't get it completely covered,so yesterday,I got a mirror and put some more on their and now it is idling perfect.What I need to do is,remove the Weber and remove the Sealant and re do it,you can't see under there.The  fuel fitting where the gas line goes to has a sealant washer that keeps it from leaking,I bought extra's and they work.Metal on metal will leak.Just wanted to let everyone know that the  plug leaks and you can't really see it,just run your finger under the plug and gas will be on your finger.I guess most people including me thought it was the gaskets that cause this idling problem.Now I know what really causes it.This weekend,I will take the Weber off and redo the sealant,i.. Here is the plug. See part 101 and 102,the fuel fitting and a little plug.,it has a sealing washer.https://www.carburetion.com/diags/3236DGAVDiaginfo.asp

Edited August 25, 2022 by Thomas Perkins

[datzenmike]

Probably the washer, either viton or copper. (may be missing?)The threads are likely for tightening and not a pipe thread that is tapered and seals the more you tighten it.

[thisismatt]

Looks like a conical seat. Maybe tighten it more...smack the wrench with your purse.

[Thomas Perkins]

If you tighten it too much,it will cause the little fuel filter to crinkle.Their is no washer missing.Does not come with one.That is why I bought another little fuel filter,it crinkled,I put the original fuel filter on a tire gauge to straighten out.You can see in the picture of the parts list that I sent in the first part that is showing no washer.The inside of the plug pushes the fuel filter into the hole.So if you tighten it all the way,it still leaks and the fuel filter is damaged.Both plugs leak.So far the sealant is keeping it from leaking and it is idling perfect.This is what I am using.I used it on the outside of the plug,not on the threads.I also use this on my valve cover screw holes and 2 half moon end pieces.Does not leak.Here is a 2 year old picture of my Weber,see how the plug is leaking.The bottom picture is when I removed the Weber,took it apart,cleaned it up,put new gaskets on it and the sealant around the plug.My Weber is 6 years old.I have put a new air filter on it.Also I have shorten the fuel feed line.The last picture is what it look's like now

Edited August 26, 2022 by Thomas Perkins

[Stoffregen Motorsports]

Yes, the filter will crinkle, but that means it is sealing inside against both surfaces.  Give it a good wrenching and tighten that sucker up good.

 

I have seen both copper and fiber gaskets. I like the copper ones best, and if they are worn, you can anneal them with a torch and reuse them.

 

 

[datzenmike]

http://www.carburetion.com/images/weber/61002.018.jpg

 

This better shows the sealing surface.

[thisismatt]

2 hours ago, datzenmike said:

http://www.carburetion.com/images/weber/61002.018.jpg

 

This better shows the sealing surface.

Exactly, it's a seat like an AN fitting, or other kind of flare fitting. Just gotta crank it down a bit. Maybe shave the inner end of the plug a little if it's crushing the filter inside?

[Thomas Perkins]

Yeah ,thisismatt I will shave the inner surface on both of my plugs to keep from crushing the filter.What it is doing is twisting the filter as you tighten the plug.In reality,the filter is too long.Since it is doing good right now,I will leave it alone,But I will shave my other one now.But I do have it tighten all the way.No more room to tighten it.I can use a drill bit the same thickness as the filter and drill into the plug a little.

[thisismatt]

Maybe the sealing surface is damaged. I've just never heard anyone mention this issue before

[Thomas Perkins]

Mine has always leaked.It leaks where you really can't see it cause of the location.If you have a Weber,just run your finger under the plug or look for leak stains.But I never thought it would cause my idle to go up and down on the tac and you can hear it.Kinda thought it was from the O ring on my idle cut off solenoid.If you use a O ring size a hair to big,it will idle real low.I have been looking everywhere to find out about my idle issue and found it to be the plug is leaking.Once the sealant stopped the leak.The idle is perfectly steady.I am now looking for my other plug to see what the inside look's like.I never thought a leak from the plug would cause this,but it does.When you screw the plug in,you have to use the box end and not have it all the way in or it won't screw completely in.If you look at the plug,you will see that the hex head is real thin.Putting to much wrench into it will cause it to bind and damaged the hex head.Not much room,Wrench is kinda too long.Back to looking for my other plug.

[Thomas Perkins]

Check out what I found.By using this with the rubber gasket.It will give it more room so the filter won't crush.What do ya'll think.

 

Edited August 26, 2022 by Thomas Perkins

[datzenmike]

It defies all understanding. It's under fuel pressure and is a very small leak. Can't possibly affect the idle. Bet wrenching on the carburetor sealed a small vacuum lean between the carburetor base and the intake. That's more believable.

[Thomas Perkins]

But it is idling perfect now Mike.Explain that.The leak is sealed,idle is perfect.Problem is solved,but the plug will leak without sealant.Tried another plug,it leaked too.Small things can make a difference,I have a brand new gaskets on it .Sometimes you have to look elsewhere and I did and have solved the problem.Simple things don't always work.A small leak can do these things.had the same thought as you but the problem was still there till I sealed that plug.You have to experience it to see it.

Edited August 26, 2022 by Thomas Perkins

[datzenmike]

When you tightened it the carburetor moved on the gasket to the intake and sealed a small vacuum leak. Go out and grab the carburetor and give it a good tug while it idles and the poor idle will probably come back.

[Stoffregen Motorsports]

17 hours ago, thisismatt said:

Maybe the sealing surface is damaged. I've just never heard anyone mention this issue before

Because it's not an issue.

 

All due respect Thomas, you're overthinking this.

[Thomas Perkins]

Up grade on my Weber.Since I have put that black Silicone on my leak.it is not leaking and the idle is perfect.Plus on the right bottom of the Weber.Their is a little copper plug.It has always leaked.When I always removed Weber and put new a new gasket in it and cleaned it up.It don't take long before gas stains appear their.But anyway I put some silicone on that and it's not leaking.Webers are very funny.Just a little leak will effect the idling.

[Thomas Perkins]

On 8/27/2022 at 12:09 PM, Stoffregen Motorsports said:

Because it's not an issue.

 

All due respect Thomas, you're overthinking this.But how come it is idling perfect now that the leak is fixed.

 

[Stoffregen Motorsports]

Don't know, but the fuel bowl is not sealed. It has a vent. And for a leak at the filter to cause it to run poorly, the fuel under pressure at the filter would have to be leaking so much that it would be puddling on the ground.