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Holley carb disassembly tips

33 IMP

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I have a 4781-3 850 dp. It's was run a little bit by a previous owner, and a little bit by me. The problem is, I need to look inside, clean it out, etc. to make it usable.
The problem is.... it was put together by Holley with the non non-stick gaskets, and it might as well be welded together. I can get the choke parts (plastic) off, and some accel pump linkages (also plastic) but the base, bowls, metering blocks and accelerator pumps are NOT coming apart.
I MIGHT be able to pry the base off, but there is NO place to pry on the bowls or metering plates.
Any good solutions out there? Chemicals to try? I don't really wanna dip the whole carb intact, and I'm not sure the currently available dip would get the job done anyway. Help?
 
I would submerge the whole carb in solution of your choice with the screews out and leave it for a few days at least. after that see how it goes
 
You could try spraying gasket softening spray on the joints and let it set overnight but I doubt it would help much. Probably a small, thin, sharpened edge paint scraper carefully used to pry them apart. The gasket remover spray will definitely help remove the old gaskets once apart.
 
Try keeping the seam wet with WD-40, hopefully it will soak in and help release the gasket bond.
 
On the crazy side of it. I purchased a cheap sonic cleaner from a cheap supply company. Mixed up simple green solution. Put carb in turned on heat and the vibrate for about an hour. The only thing is you have to keep resetting timer. Once done you have to really clean up the carb with carb. Cleaner. I was at a nothing to lose point. So figured if it didn't work would buy new one.
 
On the crazy side of it. I purchased a cheap sonic cleaner from a cheap supply company. Mixed up simple green solution. Put carb in turned on heat and the vibrate for about an hour. The only thing is you have to keep resetting timer. Once done you have to really clean up the carb with carb. Cleaner. I was at a nothing to lose point. So figured if it didn't work would buy new one.
From what I understand, the simple green will eat the color off the carb. The zinc color coat on this thing is perfect, and I'd like to keep it.
 
I use a big rubber hammer to pop the bowls off, the shock impact seems to do it, always works, never done any damage. Seen friends try to pry off bowls and sometimes there was damage.

Had friend that was a GM Dealership mech back in the '80s and that was how the factory training class taught him to get the valve covers off big block Chevys when they just used RTV and no gaskets to seal them.
 
I use a big rubber hammer to pop the bowls off, the shock impact seems to do it, always works, never done any damage. Seen friends try to pry off bowls and sometimes there was damage.

Had friend that was a GM Dealership mech back in the '80s and that was how the factory training class taught him to get the valve covers off big block Chevys when they just used RTV and no gaskets to seal them.
Thanks for that. I did try that, maybe the rubber hammer i used wasn't heavy enough, or hard enough, but no joy.
 
From what I understand, the simple green will eat the color off the carb. The zinc color coat on this thing is perfect, and I'd like to keep it.
Don't blame you there. Mine had none. It was covered in rat crap. In fact the entire top of motor was covered. Paint was dissolved. Like I had said, had nothing to lose. Good luck
 
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Whacking or prying with the carb mounted on the intake in the car. Usually the gasket rips between the two pieces and then the job gets worse.
 
My 30+ year old Holley was no fun getting apart or cleaning... even with gasket remover. I damn near threw it in the trash...
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A rubber mallet works pretty good for me with the blue gaskets but those old brown Holley gaskets are a real pain to separate and clean up.
 
As said ; beat the thing apart. This isn't your first carb rebuild, but maybe the most obstinate one. I had one like this recently. Crack the bowl off, then a screwdriver in the emulsion plugs on the the top of the metering block and pey off. Yes welded is the best description.
 
All of the ones I've ever torn apart required a nut driver or screwdriver, I've never needed anything else to get them apart. Since the handle on both are hard plastic I always just turned them around and whacked the float bowls with the plastic handle, it's worked on all of them so far and the plastic handle has never damaged anything.
 
Im in the same fix as 33 IMP, my carbs have been hanging on the wall since before ethanol was added and wielded together seems the correct term. I got a bowl tore off but damaged the metering block trying to chisel it off. Contacted a close advertised carb rebuilder and even he does not want the job. Nothing I have used to soften the brown gaskets on the out side has seemed to work. What do the pro rebuilders use for this or just don't do em, with out damage to the soft aluminum or factory dyed plating. I have thought about trying soak one in E15 gas in hopes that would assist in disolving old gaskets , but that seems rather extreme and dangerous.
 
Wow, this is a timely post. I was just about to start a thread about this same topic and my surprising success.
Preamble: I am working through reviving a barn find ski boat (story in itself). I always was leary about what I would find with the carb and prepared to purchase a new one, worst case. Being a Holley marine 4160 that is a $900 option. This carb only had 160hrs on it and appeared new on the outside but had not been run since about 1995. Shouldn't have been much ethanol fuel issues from that period. However, it was extremely difficult and time consuming to get apart. I soaked it in every carb cleaner and other potions I had and spent nearly 8 hours in the ultra-sonic bath. Eventually got it all apart except for the metering block from the main body. Strategic tapping and prying was not successful. The power valve did show a lot of corrosion on the fuel bowl side so I was expecting the same on the hidden side. After a couple of days of this I was ready to bite the bullet and place the order for a new one with Summit. At the end of the day, as beer:30 approached I soaked the perimeter, every orifice and screw hole of the metering block with Kano Kroil penetrating oil. The stuff in the can, not the aerosol. Anyone not familiar with this stuff it is the best industrial penetrating oil for rusted, heat soaked parts. Then I headed in for my beverage and let it sit overnight.
Much to my surprise in the morning and a bit of disbelief the stuff had soaked through everywhere, even the gasket and the metering body popped off with minimal force. Saved me a very expensive carb purchase and I now have a new use for Kroil.
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