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BJ8 carbs

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CaptRandy

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BJ 8 Started car up today and found the front carb SU's is overflowing out the overflow tube. Does the bolt that holds the overflow tank on remove the chamber(float tank) itself and is the flow valve accessible then?
 
CaptRandy said:
BJ 8 Started car up today and found the front carb SU's is overflowing out the overflow tube. Does the bolt that holds the overflow tank on remove the chamber(float tank) itself and is the flow valve accessible then?
Click to expand...
The bolt on top of the fuel bowl cover is removed to take the cover off and access the valve. Easy to do. Sometimes dirt can get in the fuel bowls causing the overflow and you can usually tap on the that bolt to unstick the needle/seat. Another way is with the air-cleaner removed, rev the engine and place your hand over the air-cleaner hole briefly. This will cause a rush of gas through the needle/seat and sometimes it will clear it.
 
Thanks Patrick, will try bolt first as the bottom "felt: washer looks like it is not seated correctly. Tried tapping on bolt but not successful.
 
Here's about twenty (<20) pages of pictures from the last BJ8 carbs I rebuilt; shows just about every component part, and its relative function. Some of the pictures *might* have notes on them, but I don't do write ups or how to`s.

https://spcarsplus.com/gallery3/index.php/reMKIII?page=4


IMG_1368.jpg



IMG_1373.jpg



IMG_1763.jpg



IMG_1764.jpg
 
Randy, thank you very much, manuals are great but actual photos work so much better to see what I am working with.
 
pulled out the float and it appears to have something in it. Gas does cover the top of the float in the chamber. So it appears to be sinking lower than the gas height. Have it on paper towel to see if any liquid leaks out but after hrs nothing. Should the flat be pretty much empty? I did order a new one.
Randy what size drill bit are you using for spacer sizing?
 
CaptRandy said:
pulled out the float and it appears to have something in it. Gas does cover the top of the float in the chamber. So it appears to be sinking lower than the gas height. Have it on paper towel to see if any liquid leaks out but after hrs nothing. Should the flat be pretty much empty? I did order a new one.
Randy what size drill bit are you using for spacer sizing?
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From section D.8 of factory manual:
attachment.php
 

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    FloatSpecs.jpg
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Reassembled all parts using new gaskets. Set the level of lever at about 1/2'. The carb has a Grose type float valve. Started up and no leaks. Car stalled and then the fuel pump started to pump constantly and fuel flowed out overflow tube. Restarted engine and it still flows out overflow tube. Put a small hose on the tube to capture fuel rather than just dump onto the ground. Where to go from here?
 
CaptRandy said:
Reassembled all parts using new gaskets. Set the level of lever at about 1/2'. The carb has a Grose type float valve. Started up and no leaks. Car stalled and then the fuel pump started to pump constantly and fuel flowed out overflow tube. Restarted engine and it still flows out overflow tube. Put a small hose on the tube to capture fuel rather than just dump onto the ground. Where to go from here?
Click to expand...
Check to see what overflow tube the fuel is draining from. The tubes can become twisted and you could be troubleshooting the wrong one(don't ask), I put a piece of red electrical tape around the tube near the end of it, under the car, so i know what carb is giving me the trouble.
 
Pat that is why I put the hose on one then the other to be sure, it is the forward one leaking. Seems like fuel pump fills the bowl then keeps pumping and the overflow tube pumps out the excess as a stream.
 
CaptRandy,
I had the same problem. Installed Grose valves only to find random flooding and overflowing fuel.
No problems after I changed to Viton-tipped valves.
Good luck.
Douglas
 
steveg said:
There have been problems with the newer Grose valves. You could replace them with the stock viton-tipped ones.
Click to expand...

It's a shame, too. I bought Grose Jet valves for my BJ8 when it had about 80K miles on it. I now have almost 190K and it's never flooded. I bought some of the new ones for our BN2 and one was defective (on a GJ, the bigger ball on the bottom presses against a small ball that meters flow; sometimes, the little ball gets stuck and stifles flow).
 
CaptRandy said:
Pat that is why I put the hose on one then the other to be sure, it is the forward one leaking. Seems like fuel pump fills the bowl then keeps pumping and the overflow tube pumps out the excess as a stream.
Click to expand...
Just a thought: You might want to swap the needle/seat from the good carb to the bad carb and see what happens. At least you'll confirm your suspicion.
 
Reassembled with new float. This one felt much lighter than old one. Started right up and no overflow Still have the Grose valve in and it seems to be working. Rain today so not able to take it out on the road to make sure. But looks like problem solved. Thanks for everyone's help.
 
CaptRandy said:
Reassembled with new float. This one felt much lighter than old one. Started right up and no overflow Still have the Grose valve in and it seems to be working. Rain today so not able to take it out on the road to make sure. But looks like problem solved. Thanks for everyone's help.
Click to expand...

Does the old one have gas sloshing inside?
 
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