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Newly rebuilt Q-Jet leaking at front at fuel inlet
Just rebuilt the Q-Jet and put in new fuel filter with o-ring, put it in correctly, and tighened the fuel line well. Noticing it dripping out the front where the fuel line comes in (see pic). Any ideas?
Was it leaking before you rebuilt the carburetor? If not, my logic would suggest the line is not yet tight enough. Be 100% you're using two wrenches when tightening.
Please describe exactly what you mean by o-ring. An o-ring doesn't belong in that fitting.
An o-ring goes on the end of the fuel filter between the fuel line and the body of the carb. It came with the kit and the few videos I watched showed it - and when I took the old filter out it had one.
Okay, a round nylon gasket. Around the outer diameter of the filter as it went it.
"Typically" an O-Ring "generally" implies a rubbery type black O-Ring. I thought you meant a "gasket", but Sugar Bear was right in asking. It's actually a very hard round white gasket.
^x2^ Agree it would be nice to see a fuel line w/o a kink in it.
I will get new metal fuel line, properly bent. I am 99% sure it did not leak before rebuild. And 99% sure it didn't leak for the first week or so - and running 8 or 9 times - after reinstalling it on the engine. Just noticed a few drips coming out today. I'll address the issues mentioned and report back. Thanks all.
I recognize it's like walking on pins & needles when tightening the fuel inlet lines to the carburetor - makes your teeth crush thinking you're going to go too far. If it's just a real small amount of a drip, I'd still suspect you just need to tighten it up a tiny bit more. With a new gasket, you should ever so slightly feel a little crush to the gasket - just a cinch.
"Typically" an O-Ring "generally" implies a rubbery type black O-Ring. I thought you meant a "gasket", but Sugar Bear was right in asking. It's actually a very hard round white gasket.
I should have chosen my words my carefully. thanks guys.
Definitely not trying to split hairs ( I don't have any to spare) but hoped it was an o-ring in there... would have been an easy solution. That connection is one where experience helps.
Definitely not trying to split hairs ( I don't have any to spare) but hoped it was an o-ring in there... would have been an easy solution. That connection is one where experience helps.
Doh! Not sure what I was thinking there with that comment. Too much sun today, I guess. Yeah, if it was an O-Ring it would have been an easier fix to remove it. Some days for me....
Break the line loose (9/16” wrench iirc), check tightness of filter housing (1” wrench iirc), retighten the line. My personal **** retentiveness calls for anti seize on the flare face ( just barely a film), on the back of the flare and line inside the nut and some on the threads. Prevents corrosion and binding which is likely the reason for the kinked line. Re tighten the line and the leak may be fixed due to the slightly tighter connection.
Strangely, my retentiveness does not absolutely dictate a new line, that would probably only cause an issue on a long, heavy load and throttle situation but definitely better replaced. Anti seize both ends of the new line.
Break the line loose (9/16” wrench iirc), check tightness of filter housing (1” wrench iirc), retighten the line. My personal **** retentiveness calls for anti seize on the flare face ( just barely a film), on the back of the flare and line inside the nut and some on the threads. Prevents corrosion and binding which is likely the reason for the kinked line. Re tighten the line and the leak may be fixed due to the slightly tighter connection.
Strangely, my retentiveness does not absolutely dictate a new line, that would probably only cause an issue on a long, heavy load and throttle situation but definitely better replaced. Anti seize both ends of the new line.
Make sure you are using flare nut wrenches on those nuts.
As was suggested, the flare may be leaking because it is not seated fully due to the fuel line not lining up very well. Probably why it was bent in the first place. Between the replacement fuel pumps and the reproduction lines, it is kind of hit or miss on getting them to line up well. Worth also investing in a little tube bender, so you can make tweaks to the line without getting what you have now. It also may be easier to loosen up the carb mounting to intake bolts so you can wiggle it a little bit to get the fuel line to line up. Tighten the line, then tighten down the carb bolts in a cross pattern order, like when you are tightening down a wheel.
Hopefully the OP isn't in need of that and his threads are good.
Thanks guys. Yea, hopefully the threads are good. I think if I get the new fuel line, (I have the bending tool), and then loosen carb bolts and put a slight film of anti seize at end of flange and on threads as described, I should resolve the issue.
Hmmmm. Just wondering if i have a flange tool to flare the ends, like I do for smaller brake lines....
I'm sorry. I've been following this thread and I still don't know for sure if the leak is between the fuel inlet fitting and the carb body or between the flare nut and the inlet fitting. Qjet inlet fittings come in two flavors, the 7/8" fittings on early carbs that use the fiber washer (top in the photo below) and the 1" fittings on the later carbs that use the nylon washer (bottom in the photo). Your fuel fitting almost looks like the early style that uses the fiber washer. Is this what you have? It's hard to tell from your photo above.
I'm sorry. I've been following this thread and I still don't know for sure if the leak is between the fuel inlet fitting and the carb body or between the flare nut and the inlet fitting. Qjet inlet fittings come in two flavors, the 7/8" fittings on early carbs that use the fiber washer (top in the photo below) and the 1" fittings on the later carbs that use the nylon washer (bottom in the photo). Your fuel fitting almost looks like the early style that uses the fiber washer. Is this what you have? It's hard to tell from your photo above.
One way to avoid this happening is to use a fuel filter on the rubber hose to the fuel pump inlet. This way you never have to remove the hard line at the carburetor.
April 3rd, 2023, 03:08 PM
