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Topic Review (Newest First)
04-16-2008 08:02 AM
Sixtyninemercury After BG said that they aren't sure if their carb is bad - even though I said that I have a tuned Holley carb to verify my motor's integrity? So what did BG expect? For me to send the defective BG carb back to them so they could say that they tested it and found no problem? B.S.!!! I sent it back to Jeg's and they are good with their word - in three days I got a total refund - no questions asked!
04-07-2008 10:03 AM
Sixtyninemercury To the BG tech - thanks - I can see that you did try to help me. That's good.

It's already heading back UPS-wise to the vendor who sold it to me for a full refund. If it works like that outta the box one time I don't play anymore. I've had an Edelbrock carb, two fuel pumps, seven Holley's and everyone of them worked well enough to drive outta the box. PERIOD.


The silver lining in this dark cloud is that because of all of this I ended up later putting on a 3/8" aluminum open element spacer (not the Holley pressed-fiber spacer that I was using to troubleshoot the BG carb!) between my manifold and my Holley. I had tried a 1" open spacer years earlier and it wasn't drive-able because of not enough idle vacuum. The 3/8" spacer is totally drive-able and a nice gain at the top-end of my powerband - see SBF Air-Gap manifold is totally dual plane up top so at WOT each cylinder can only be feed from two barrels - but with the open spacer now each cylinder can get feed from all four of my Holley's barrels!!! I'm stoked!
04-05-2008 02:13 PM
Sixtyninemercury
Quote:
Originally Posted by Kruzin Karl
This thread begs for the question, (and trust me, absolutely no sarcasm intended) if the car runs that good with the holley (sounds nice!), why did you lay out that kind of money to change out the carb?
Because I've tuned Edelbrocks - then in my opinion moved up to Holley - and then I've heard that BG carbs - especially the annular ones - are something to look into. I was planning on learning the tuning process for the BG carb that I bought and to have my excellent Holley as a back-up. (Having a back-up is a real good idea - trust me!) In my case I needed a back-up carb - 'cuz if you read my thread everyone kept thinking it's my motor or my A/F gauge. Of course in the beginning I wondered too - but the tuned and working Holley removed any doubt - otherwise I could have been distracted and maybe wasted more time chasing problems that aren't really there!
04-05-2008 12:45 PM
Kruzin Karl This thread begs for the question, (and trust me, absolutely no sarcasm intended) if the car runs that good with the holley (sounds nice!), why did you lay out that kind of money to change out the carb?
04-05-2008 11:40 AM
malc If that is the case then don't you think that it would do it on the Holley, too?!?


Ya got me there, I must have had a brain fart.
04-05-2008 09:59 AM
Sixtyninemercury
Quote:
Originally Posted by malc
Air could be getting in at the manifold to head gasket.

Have you checked the plugs ?

Edit: BTW, areŽnt you going to wait for that spacer ?
If that is the case then don't you think that it would do it on the Holley, too?!? Ah - yeah! My motor is very sound - trust me. Have a listen with the Holley on it:
http://media.putfile.com/My-69-Merc-...Flowmaster-50s

The 3/8" Holley gasket (open-element) that I just posted is a spacer and I checked - it fully covers what I thought was open carb base vacuum passageways - spraying of the carb cleaner would have tipped me off if there was a vacuum leak present, also.
04-05-2008 09:32 AM
malc Air could be getting in at the manifold to head gasket.

Have you checked the plugs ?

Edit: BTW, areŽnt you going to wait for that spacer ?
04-05-2008 09:09 AM
Sixtyninemercury This morning I drove the car until it got to it's same-ol'-same-ol' lean condition - pulled into a park - left the motor running and sprayed all around the carb's base, vacuum fittings, etc. No difference in idle at all! No vacuum leaks anywhere - that carb is sealed up tight.

I switched back to my Holley (0-82750) and the car runs again like it should for thirty minutes, an hour or whatever. I'm not going to say the BG stuff is junk - because to be fair that is the only product that I've ever bought that is a BG - but this carb obviously does not work - and it has nothing to do with my tuning skills (I've been tuning carbs for years - Edelbrock and Holley) nor my A/F meter.

I'm through with the headaches this carb has given me - now it's refund time.
04-04-2008 09:16 PM
Sixtyninemercury Put on Holley's 108-12 thick flange gasket - no good progress - car runs excellent until it warms up fully to operating temp and then goes to a lean condition. What is now really strange is that that flange gasket is real thick and made from a pressed paper type substance that appears to not conduct heat - yet the motor still leaned out after about 7 minutes - the same time as before when it was metal on metal with the thin OEM gasket in between that was sent with the BG carb!

After I started the motor and got it to run on it's own well I sprayed carb cleaner around the base and didn't get a reaction. I wanted and needed to spray after the motor went to it's lean condition but it is Friday night - I'm tired from the week and it's too dark.

Tomorrow morning I'm gonna bring the spray and also cap off the manifold vacuum fitting on the carb that I was using for my vacuum meter (it's next to the tach) just in case after everything gets hot the ill-fitting (?) hose might be letting un-metered air in.

Now that I've calmed down a bit I know there are only two things that are causing my lean condition:

Only after the motor gets warmed to operating temp:

1) Somehow un-metered air is getting into the manifold's plenum

or

2) The fuel supply in the carb that is supposed to be exiting through the annular boosters is getting reduced - that I don't know how to check without a high-speed camera which I don't have?
04-04-2008 03:52 PM
Sixtyninemercury
Quote:
Originally Posted by Tech @ BG
We have not only answered your pm but also posted in one of the many other threads you have posted. Seems the members here are telling you to start the same place we did as well as the members on the other boards. We are glad to help but please dont trash us because you have multiple threads going on multiple boards and we dont answer the same question in all of them.
I have not trashed you - I have not said your carbs are crap or other things that others have said and that I have read. I PM'd you and you did not PM me back for a long time after I received notice that my PM to you was read - when I posted that you had NOT posted anything anywhere - I've been watching.

I have posted in other forums because I want different opinions to help me fix it - I'm sure the only one who really knows right off of the bat doesn't exist.

I noticed that you read my PM very early this morning and took what - ten or more hours to reply this? I've been paying close attention.

Obviously I'm not going to put the carb's jetting back to baseline because it will further lean out my motor and I know you don't want me to waste my motor.

I'm gonna check the carb's base for vacuum leaks and install a carb spacer to see if it will seal any openings for air to get in when hot.
04-04-2008 03:40 PM
Tech @ BG
Quote:
Originally Posted by Sixtyninemercury
I have PM'd the guy on this forum who says he is the BG tech - I can tell that he has read my PM but hasn't returned me a PM yet with any advice.
We have not only answered your pm but also posted in one of the many other threads you have posted. Seems the members here are telling you to start the same place we did as well as the members on the other boards. We are glad to help but please dont trash us because you have multiple threads going on multiple boards and we dont answer the same question in all of them.
04-04-2008 01:45 PM
Sixtyninemercury I'm still awaiting for the BG tech's reply to my PM that I sent him.
04-04-2008 12:51 PM
Sixtyninemercury
Quote:
Originally Posted by malc
I have never had mine installed without a spacer.
First off I had a half inch to give me clearance for the brake booster vac. under the rear floatbowl.
Be patient the BG tech guy will eventually get back to you, heŽs pretty good.
Thanks - it's just frustrating because this is my umpteenth carb I've owned/tuned - but the first of BG carbs - and I just dropped $560 on it and the fuel plumbing accessories! I've never had this problem before. I guess this is a time to learn something new - but for that money I'm not pleased!
04-04-2008 12:44 PM
Sixtyninemercury Maybe here or there (the red circled ones)???

[IMG]
04-04-2008 12:43 PM
Boosted89RS
Quote:
Originally Posted by Sixtyninemercury
Yes mine is heated. This motor has had many carbs on it - Edelbrock and Holley - and this is the first time I've ever had this crazy experience on my A/F meter. I am experienced enough to tell how it drives after it warms up and the meter is just confirming what I am feeling through the gas pedal.

It is not the meter!
alright figured id throw that up there alot of ppl dont realize that those narrow band meters are not accurate at all
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