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tahoe healey

tahoe healey

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After a nice ride where the BJ8 ran very well in the HEAT and some traffic, there was surging for a few blocks after stopping for lunch. It was less in third and forth at higher RPMs. It diminished as it cooled and finished the trip fine. It has happened before. Any ideas as to what I'm dealing with? Thanks.
 
A bit of fuel starvation from fuel vaporization in the float chambers or carb passages. As soon as you get more fuel flowing & things cool from increased air flow it's ok. Good heat shielding & more fan flow might reduce the problem, but the problem is not unusual. A metal fuel filter near the carbs can trap quite a bit of vapor which has to be forced through before liquid fuel can flow into the carbs. Make sure that the carb float bowl venting is working well & not obstructed, so that vapor can escape.

The RVP (Reid Vapor Pressure) of the fuel is often tailored to seasonal temperatures & altitudes. A fuel formulated for higher altitudes & or hotter weather should vaporize less easily. You may find that a different fuel supplier would help. This happens most often when low volume fuel suppliers get "caught" with winter blends during an early hot spell.
D
 
Thanks, Dave. How can I tell if there is a venting problem? I have the BJ8 with the float tanks between the carbs. I use a clear plastic filter but it is near the front carb. I have talked to others who have experienced this also.
 
Rich,
About all you can do is see if there is free air passage through the banjo & its tube. One thing to check, the washer between the carb top & the banjo should have internal scallops in it to permit air passage around the center bolt from float bowl to banjo. Moss # 370-160. If the scallops are missing, no vent. The washer on top of the banjo should of course be non scalloped to prevent leaks. Moss # 370-130.
D
 
Okay. Thanks, Dave. But how does the vent work? There is the scalloped fiber washer but with metal above and below. Does that nut not get tightened all the way? The fiber washer sits on the top, then the brass banjo,right?
 
Hello TH,The venting is through the overflow tube. The assembly procedure is: Scalloped paper washer.Brass Banjo, Aluminum washer and a carb ID plate If you still have it. The bolt is inserted throught this entire assembly and tightened down securely.---Fwiw---Keoke
 
Hi TH,
The holes in the lid & in the banjo are larger than the shank of the lid hold down nut. The vent path is around the nut shank, through the scallops, to the banjo. Scalloped washer (370-160) on lid, banjo, aluminum washer (370-130), hold down nut head.
D
 
Thanks. As soon as I shut down the computer I realised how stupid the question was. I allow one stupid mistake a day. I thought I was doing great. I made it all the way to 10:30 PM. The banjo has a "vent" pipe. Dah!
 
[ QUOTE ]
The banjo has a "vent" pipe. Dah!

[/ QUOTE ]
Yeah, that's the purpose of the banjo. A place to connect the pipe. Don't feel bad, we all do it once in a while. In my case, more often.
D
 
I always recomend throwing away all after market filters and relying on the little factory screens in the float lids for this very reason.
 
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