Holly Rebuild Help
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
Holly Rebuild Help
I got the Holly rebuild kit 510-37-754 and started to rebuild it. Even though it comes with "Instructions" there isn't one mention of which part goes where. Many of them are very obvious, but there are others that either I don't use or I haven't found them yet. Kind of frustrating there isn't better detail for all the small parts for first-timers like me.
Here is a picture of the kit with some of the parts in question highlighted. Any help on where the little white plastic pieces go? I've been all over the internet and on Holly.com but I just can't seem to find any specific information.
Here is a picture of the kit with some of the parts in question highlighted. Any help on where the little white plastic pieces go? I've been all over the internet and on Holly.com but I just can't seem to find any specific information.
Burning Brakes
Joined: Oct 2008
Posts: 1,037
Likes: 14
From: Mobile Alabama
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
Okay, now which parts are those on the diagram. I have seen many diagrams, it's hard to distinguish which items on the diagram are the little white plastic pieces, the cork with a hole in it, and little round disk sticker. Maybe everyone just uses a few items out of the kit and tosses the rest.
Racer
Joined: Feb 2009
Posts: 273
Likes: 11
From: Algona, WA
Okay, now which parts are those on the diagram. I have seen many diagrams, it's hard to distinguish which items on the diagram are the little white plastic pieces, the cork with a hole in it, and little round disk sticker. Maybe everyone just uses a few items out of the kit and tosses the rest.
Model 4160- has side pivot floats, single fuel feed with a secondary transfer tube. A primary metering plate and a secondary fixed orifice metering plate. Idle mixture screws on the primary side only. Vacuum secondarys.
Model 4150-has center pivot floats, dual feed with primary and secondary metering plates that have replaceable jets. They can come either 2 or 4 idle circuit. Either vacuum or mech. secondarys .
The 8 large white plastic gaskets that you have highlighted are for the front and rear bowl screw gaskets.
The gaskets on the left are fuel inlet gaskets, the center left is a power valve gasket. You will use the gaskets on the right which are 2 bowl inspection gaskets, upper and lower gasket for primary squirter gasket. The metal check ball on the bottom is for vacuum check ball in
the diaphram for the secondaries.
You only use the gaskets and parts that your carb needs. Yes there are extra parts left over especialy the clips and pins. The little square cork gasket is sometimes used between the choke rod and the main body where it pass's thru. Can't tell what the other highlighted parts are.
Good luck,
Dave
Pro
Joined: Nov 2013
Posts: 730
Likes: 37
From: Catoosa Okla
You should have two (2) of those little cork thick o-ring looking things that go into the front metering block of the Holley. The two idle air bleed adjustment screws then thread into the area where you placed the cork o rings. The white gaskets your referring to seal the float bowl adjustment screw. (on top of the primary of front fuel bowl). Some also used the black washer looking gaskets for the float level assembly.
Also understand, your carb "kit" is a rather universal kit designed to handle a plethora of different carburetors and applications. Your gonna have a nice handful of "extra" parts. You may have more than one power valves. I believe a 6.5 is a good average street power valve. The rating of the valve is usually stamped on it's side.
Also understand, your carb "kit" is a rather universal kit designed to handle a plethora of different carburetors and applications. Your gonna have a nice handful of "extra" parts. You may have more than one power valves. I believe a 6.5 is a good average street power valve. The rating of the valve is usually stamped on it's side.
Pro
Joined: Nov 2013
Posts: 730
Likes: 37
From: Catoosa Okla
You should have two (2) of those little cork thick o-ring looking things that go into the front metering block of the Holley. The two idle air bleed adjustment screws then thread into the area where you placed the cork o rings. The white gaskets your referring to seal the float bowl adjustment screw. (on top of the primary of front fuel bowl). Some also used the black washer looking gaskets for the float level assembly.
Also understand, your carb "kit" is a rather universal kit designed to handle a plethora of different carburetors and applications. Your gonna have a nice handful of "extra" parts. You may have more than one power valves in the kit. I believe a 6.5 is a good average street power valve. The rating of the valve is usually stamped on it's side.
Also understand, your carb "kit" is a rather universal kit designed to handle a plethora of different carburetors and applications. Your gonna have a nice handful of "extra" parts. You may have more than one power valves in the kit. I believe a 6.5 is a good average street power valve. The rating of the valve is usually stamped on it's side.
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
This kit is for a 4150/4160 carb. You only use the parts needed for your carb. The difference between the 2 are.
Model 4160- has side pivot floats, single fuel feed with a secondary transfer tube. A primary metering plate and a secondary fixed orifice metering plate. Idle mixture screws on the primary side only. Vacuum secondarys.
Model 4150-has center pivot floats, dual feed with primary and secondary metering plates that have replaceable jets. They can come either 2 or 4 idle circuit. Either vacuum or mech. secondarys .
The 8 large white plastic gaskets that you have highlighted are for the front and rear bowl screw gaskets.
The gaskets on the left are fuel inlet gaskets, the center left is a power valve gasket. You will use the gaskets on the right which are 2 bowl inspection gaskets, upper and lower gasket for primary squirter gasket. The metal check ball on the bottom is for vacuum check ball in
the diaphram for the secondaries.
You only use the gaskets and parts that your carb needs. Yes there are extra parts left over especialy the clips and pins. The little square cork gasket is sometimes used between the choke rod and the main body where it pass's thru. Can't tell what the other highlighted parts are.
Good luck,
Dave
Model 4160- has side pivot floats, single fuel feed with a secondary transfer tube. A primary metering plate and a secondary fixed orifice metering plate. Idle mixture screws on the primary side only. Vacuum secondarys.
Model 4150-has center pivot floats, dual feed with primary and secondary metering plates that have replaceable jets. They can come either 2 or 4 idle circuit. Either vacuum or mech. secondarys .
The 8 large white plastic gaskets that you have highlighted are for the front and rear bowl screw gaskets.
The gaskets on the left are fuel inlet gaskets, the center left is a power valve gasket. You will use the gaskets on the right which are 2 bowl inspection gaskets, upper and lower gasket for primary squirter gasket. The metal check ball on the bottom is for vacuum check ball in
the diaphram for the secondaries.
You only use the gaskets and parts that your carb needs. Yes there are extra parts left over especialy the clips and pins. The little square cork gasket is sometimes used between the choke rod and the main body where it pass's thru. Can't tell what the other highlighted parts are.
Good luck,
Dave
That is the first and only information that actually states what goes where. I may seem like an idiot, but there are things on this carb that don't match those parts, whether that was a previous bubba build or simply because it's older, I don't know. Those white plastic things, I don't have anything like that on the bowl bolts, most were missing gaskets and if it did have one is was completely different. I was assuming that is where they went, but in trying to do a rebuild the right way, I HATE assuming and was looking for positive identification.You can't seem them very well in the picture, but there are these little white coils of plastic that look like curled up wood shavings. I haven't a clue if they are something that I should be using or not.
I figured out the cork gaskets for the idle mixture screws and many of the others now.
By the way, the power valve was shot. Man am I glad I decided to tear this thing down and rebuild it. I could have been fighting many of these problems.
Guys, thanks so much for your help!
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Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
This kit is for a 4150/4160 carb. You only use the parts needed for your carb. The difference between the 2 are.
Model 4160- has side pivot floats, single fuel feed with a secondary transfer tube. A primary metering plate and a secondary fixed orifice metering plate. Idle mixture screws on the primary side only. Vacuum secondarys.
Model 4150-has center pivot floats, dual feed with primary and secondary metering plates that have replaceable jets. They can come either 2 or 4 idle circuit. Either vacuum or mech. secondarys .
Dave
Model 4160- has side pivot floats, single fuel feed with a secondary transfer tube. A primary metering plate and a secondary fixed orifice metering plate. Idle mixture screws on the primary side only. Vacuum secondarys.
Model 4150-has center pivot floats, dual feed with primary and secondary metering plates that have replaceable jets. They can come either 2 or 4 idle circuit. Either vacuum or mech. secondarys .
Dave
Dave, I'm not arguing this, I'm just confused. My list (R80508-1) states that it's a 4160.
However, this carb most definitely has center hung floats. All the other documentation like the exploded view show the 4160 as having side floats. You can see why I'm having difficulty sourcing good information on rebuilding this thing.
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
The float bowl screw gaskets have always been made of cardboard in the past. I guess they have gone with the plastic. Place them on the float bowl screws and slide them to the head of the screw. I have also seen them stuck into the float bowl recess and the screw inserted after. The white thin curls of plastic appear to be throttle shaft gaskets/bushings. Not something I would change unless you are sure to need to. The throttle blade screws must be removed and the shaft pulled out. This could allow the screws to come loose later as the penned over end is removed with the removal of the screw. mike...
Racer
Joined: Feb 2009
Posts: 273
Likes: 11
From: Algona, WA
Dave, I'm not arguing this, I'm just confused. My list (R80508-1) states that it's a 4160.
However, this carb most definitely has center hung floats. All the other documentation like the exploded view show the 4160 as having side floats. You can see why I'm having difficulty sourcing good information on rebuilding this thing.
However, this carb most definitely has center hung floats. All the other documentation like the exploded view show the 4160 as having side floats. You can see why I'm having difficulty sourcing good information on rebuilding this thing.
No one wants to look under a hood a see a carb that looks like it came of a truck.
Just use the parts in the kit that your carb needs. The little curly que white plastic things are probably the new throttle plate bushings. I wouldn't change those unless absolutely had to! Only bad things can come from taking the base plate apart if you are not truly competent in there reassembly.
Your carb is one of the later generations. On the base plate only remove the six screws that hold it to the carb body. Select the gasket that match's your old gasket exactly in size as well as hole placement.
DO NOT TAKE APART BASE PLATE ASSEMBLY!
Now separate between sub assemblies. They will be primary bowl, secondary bowl, main body, vacuum diaphragm assembly and front and rear metering plates, as well as the previous mentioned base plate.
Now e-mail LARS for his how to rebuild a Holley carb.
Good Luck!
Dave
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
See without your guys input I may have just tossed those pieces not knowing if they were for this carb or not. Only issue, there is only one set. I hope the primary isn't the same way.
Last edited by ctuinstra; Mar 15, 2014 at 03:24 PM.
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
If you are sure you have it back together correctly, use thread locker on those screws. Red if you are done with it forever, blue if you want to take it apart in the future. I agree with contacting Lars on all things carburetion. mike...
Burning Brakes
Joined: Sep 2009
Posts: 1,124
Likes: 140
From: Western New York
One more thing to check. Make sure the power valve you replace is the same number as the one you removed. They have a number on them, like 6.5 which is the vacuum at which it opens. Makes a big diff in how your engine will run if you use the wrong one.
Duane
Duane
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
I backed off the idle screws and set the plates in there and tightened the screws and made sure they didn't bind. Also helt it up the light to see a perfect halo around the plates. The return sripng wouldn't return the primary and now it slaps it shut. I'm very happy with the way it's turning out. I have a few more specific questions and I will get in touch with Lars about. Hopefully in the next couple of days I'll have it back on with new wires and plugs and I get back to tuning it.
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
Yep. Got a 65 to replace the 65. I'm curious to see how much that effected it but since there were so many things wrong ill never know.
Thread Starter
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
These are about the only left over parts (short of the e-clips, etc) I have not figured out if I have missed something or if these don't go to this carb. They don't fit the float adjustment screws/bolts. I've already replaced the float sight with different ones. They are metal.
I have no idea what the round cardboard is for.
I did figure out what the square cork with a hole was for; its actually precut and you can't see it until you bend it. It's for seal to the secondary vacuum assy. Goes between the vacuum assy and the carb body.
I have no idea what the round cardboard is for.
I did figure out what the square cork with a hole was for; its actually precut and you can't see it until you bend it. It's for seal to the secondary vacuum assy. Goes between the vacuum assy and the carb body.
