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 Post subject: Holley questions
 Post Posted: Sun Mar 25, 2012 11:24 am 
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I'm putting a 4500 back together and the discharge needles are not the same. One looks like brass and the other looks like every Holley needle I've ever seen. The diameters are the same and the lengths are almost the same. Does it matter where they go?

I adjusted the idle on a friends carb with "O" ring seals for the idle A/F adjusters. The "O"" rings would come out as the screw was adjusted out, but didn't go back in as the screw was turned back in. This resulted in the screws vibrating out to the point where the car would hardly run. Did he have junky O rings, did he put them in wrong or are they just not the way to go? I put some cork seals in and the problem was fixed.

I put BLP banjos in and 2 of the 4 have some play. The BLP go in very easy by hand, which seemed odd to me. I've installed Holley's before and had to tap them in. Is this worth worrying about?

Thanks for any advice.


Last edited by Ron Gusack on Sun Mar 25, 2012 3:04 pm, edited 1 time in total.

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 Post subject: Re: Holley questions
 Post Posted: Sun Mar 25, 2012 12:22 pm 
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Ron I assume you're talking about the accelerator pump check valves? They make them in both brass and SS but I don't think it matters unless you're running methanol. Methanol has been known to make those brass valves stick when the fuel corrodes them.

I use the "O" rings on idle screws and haven't had a problem to date? Maybe they weren't all the way in to begin with. I put those in and take a small screw driver and push them to the bottom of that hole. Use a little lube on the screws which will help putting them in. Once you've bottomed the screw and backed them out the needed amount there "shouldn't" be a problem with them coming out unless they are the wrong size, which sounds like the problem.

Not sure on the boosters as I've never installed them with the stake tubes but I'd be concerned if it was me. I know they are suppose to be a little snug and maybe some punch marks along the sides will tighten them up a bit.

Maybe Mark or Bruce will have a suggestion on that.

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 Post subject: Re: Holley questions
 Post Posted: Mon Mar 26, 2012 6:33 pm 
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Thanks Ken, I didn't explain the banjo thing very well. Two of them will wiggle about 1/32. I had to tap the banjo lightly to get it to seat in the main body, but the pins went in very easy. Mark at BLP told me most 4500 boosters have a little play. I've messed with 10-12 4500's over the years and never had one with loose boosters. Maybe it's not enough to worry about.


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 Post subject: Re: Holley questions
 Post Posted: Mon Mar 26, 2012 6:42 pm 
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I've seen a few loose, but the pins usually go in snug and keep them tight. The newest banjo's I've got recently actually have to be reamed for the pins to fit right.


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 Post subject: Re: Holley questions
 Post Posted: Wed Mar 28, 2012 9:48 pm 
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I've started using plastic idle screw seals from QFT. They work real well. Really all they are is a small piece of clear plastic hose cut about 1/8" long. These: http://www.summitracing.com/search/?key ... -100&dds=1

pn: 27-100

They will not back out and will not leak like the cork ones sometimes do.

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 Post subject: Re: Holley questions
 Post Posted: Wed Mar 28, 2012 10:39 pm 
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Another McMaster Carr buy for mixture screw seals, you can get 1/4"OD/1/8"ID silicone tubing. They have a rigid and soft, either works but the rigid is what I've seen used. 10 ft will last a lifetime. Cut to length about 3/16-1/4".


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 Post subject: Re: Holley questions
 Post Posted: Wed Mar 28, 2012 11:25 pm 
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Mark, are you sure that silicon tubing will work with gas? Put a piece in some gas and leave it there a while and see what happens to it. The silicon tubing might work OK on methanol or maybe even E85 but I'd check it in race gas before I went to the trouble of changing to that material.

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 Post subject: Re: Holley questions
 Post Posted: Thu Mar 29, 2012 8:08 am 
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Ken may be right on the silicone tubing. Ask any model airplane builder. Silicone is for methanol/nitro and rubber/nitrile for gas and diesel. Gas and diesel make the silicone swell up. I think the ones from BLP are plastic. I did recently buy some yellow stuff for my weed whip. It came in various sizes. That may work as well.

However, I don't think there would be much fuel coming back along the mixture screw threads so it may not be a problem. I'm fixin' to try it myself soon.


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 Post subject: Re: Holley questions
 Post Posted: Thu Mar 29, 2012 10:21 am 
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nomad wrote:
Gas and diesel make the silicone swell up.


THAT has been my experience int he past. Over time gas will cause the silicon tubing to break apart and it will crumble up in little chunks. If you leave it in there long enough I'd bet it will completely disintegrate. :-k

But yeah Bruce, Model boats/airplanes in my past taught me this. I've got 3 R/C boats hanging on the wall here now. Built one airplane and few it ONCE! O:) =;

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 Post subject: Re: Holley questions
 Post Posted: Thu Mar 29, 2012 9:55 pm 
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Ken, sorry if you've already seen this RC SR71, but if you haven't, give it a look. The fly by at about 3:20 in is unreal. This guy is pretty well known in the RC airplane world.

http://www.youtube.com/watch?v=SDbQ5xvsrIU


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 Post subject: Re: Holley questions
 Post Posted: Fri Mar 30, 2012 12:03 am 
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Ron Gusack wrote:
Ken, sorry if you've already seen this RC SR71, but if you haven't, give it a look. The fly by at about 3:20 in is unreal. This guy is pretty well known in the RC airplane world.

http://www.youtube.com/watch?v=SDbQ5xvsrIU


Thanks Ron, I had seen that one before but it was a while back.

Faye and I went to the Aero Space museum about 10 years ago and they got a real one of those in the middle of that place. I walked around that thing for probably half an hour and was amazed. That was the best thing on display there!

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