Holley carb kit, adjust float level? Help!

[GaryWilkinson]

 

My 95 Nautique was running rough-ish at the end of last year and decided to do a carb kit. Got it all done and started it up to what sounded like a Topfuel dragster on the staging line it was that rough. Couldn’t hold and idle less than 1500 rpm and it was loud and tons of grey smoke and burnt oil coming out. I figured it was the fogging oil (hopefully) shut it down and talked to mechanic who said did you set the float levels?

 

Can’t find those screws on my model of carb.

 

Any ideas?

 

 

[Jetsetr]

The Holley 4160’s either have non adjustable float bowls or adjustable...

I’m THINKING you have a stuck float/needle and seat or two. Tap the float bowl with a hammer (seriously) sometimes that’s enough.

 

Otherwise you need to remove the bowl and slightly bend the float tab to lower the float.

Pull the air cleaner off and see which side is dumping the fuel in...report back and we will go from there.

[Orlando76]

Marine Holleys aren’t externally adjustable.

[Jetsetr]

I swapped the adjustable bowls onto my 4160. Pretty sure your correct Orlando76.

[GaryWilkinson]

@Jetsetr @Orlando76 agree, no external adjustments.

The gas is FLOWING from the primary side. Nothing (yet) from the secondaries.

 

Any documents / videos you could point me to would be great. Haven’t found anything yet.

 

Is it as simple as taking off the 4 bolts that hold each side on? Gotta be careful of those transfer tubes that crossover to the other side.

 

Any info is really appreciated. Thanks fellas.

 

 

[Orlando76]

Not to be a smartass but YouTube and google. Keep in mind it’s a MARINE 4160. Auto 4160 has external adjustable floats. Open it up and make sure needle is seating properly. Does your engine sit level? Some inboards don’t sit level so primary float typically overflows and secondary starves.

 

Most carb guys will disagree with me but next time just buy a brand new marine 4160 from Summit calibrated for the Ford or Chevy. Bolt it on, adjust idle and voila it’s good. You’ll always be happier with a new carb vs a rebuild.

 

Edit-Nevermind I re-read thread. 95 Nautiques sit level.

 

We know your carb is jacked now, but back to last seasons issue, what ignition system are you running on that boat?

[ReallyGottaSki]

Well not exclusively..

Indeed most marine holleys have no external adjustment but its not hard and fast.

But what you shouldn't see are any bowl plugs for setting the level.

for instance list 9022

http://www.holley.com/0-9022.asp

 

Gary

 

Holley Blue bowl gaskets let you take the bowl off a couple times with no damage and

 

Yeah something is amiss with the primary float/neede/seat. go in there and chech for gunk. If trash in there, investigate how it got past the filter.

 

A little oil on the xfer tube orings help with leak-free assembly. then roll and push the xfer tube around fore/aft and seat the orings well after assembly.

 

[BraceMaker]

@Orlando76 - I don't disagree - but you can send them to a few people for tuning for less than half price and it works great. In some ways this also helps to get the correct power valve etc.

 

In future however I do not recommend doing a carb rebuild before checking on the ignition system. As often rough running is poor ignition while a strong ignition system will fire off some very poor carb settings.

 

[Jetsetr]

@GaryWilkinson remove the 4 bolts/screws in the corner of the float bowl. Also remove the fuel line (and use the correct wrenches or fuel line wrenches so you don’t round off the nut). Remove the fuel line FIRST. You can do all of this with the carb still on the engine, but you will need to catch the fuel in the bowl. Not that much, but enough to make a mess and fire hazard.

 

SAVE yourself a bunch of trouble and buy some blue float bowl gaskets and transfer tube O rings first! Nothing more frustrating than to have fixed the problem and and have the transfer tube leaking fuel and ya have to take it apart agin. Just replace them when the bowl is off, and make sure they’re not rolled and seated properly. I use a touch of a product called “fuel lube” but a touch of grease works well too, it lets them move a bit while installing. As mentioned the blue float bowl gaskets can be reused a few times. I’m guessing the needle is stuck wide open for some reason (junk, or hung up) or you have a bad float. A bad float will sink and keep the needle open all the time.

 

Where are you located???? If close I will fix it for you if it’s still giving you trouble.

 

These carbs are REALLY simple...

I have a 4160 on the shelve here and will take some pics of the internals for you...

 

@Orlando76 I’m really not into throwing $650-750 away on a new carb to fix a really simple problem, and as someone who grew up with nothing I always had to at least TRY to repair stuff.

 

Feel free to PM and I can give you my phone number if you’re still having trouble.

 

 

[2Valve]

I rebuilt one of these for a friend's boat some years ago and we spent a great deal of time getting the floats adjusted perfectly. It was a nice improvement in running and idle. People don't realize how critical float adjustment is on any engine.

[Orlando76]

@Jetsetr I partly agree with you, but....No disrespect to Gary but I feel no matter what he’s going to be into this for $600 IF he doesn’t solve this issue himself. I feel the mechanic he talked to isn’t a marine mechanic. As the mechanic should’ve said “how’s the ignition, and btw marine 4160’s (and all post 1972 marine holleys as far as I know) don’t have external float adjustments?” Now he’s going to have frustration and downtime to factor in. Is he in Canada? What’s that like a 5 day season? I like to fix and figure things out myself. I also know that if I don’t fix and make that carb perfect in 1 R&R, once I factor in frustration and downtime, I could have easily gone to work and made that $699 for a brand new carb with minimal frustration.

[Jetsetr]

@Orlando76 I totally understand your point/position....

[Jetsetr]

Pic 1 Inside float bowl. White plastic guard comes right out. Brass vertical thing is the needle and seat assembly.

Pic 2 needle and seat removed, that small clip holds the float on.

Pic 3 transfer tube and O ring

Pic 4 needle and seat assembly.

This is a externally adjustable float bowl, what you have is similar. See if there’s any debris holding the needle off the seat. Shake the float and see if there’s any gas in it. If so it’s junk replace it.

[ALPJr]

SkiDim. I got a new 4160 from them for our Prostar. I was surprised how easy of a job the replacement was and how much better the motor ran.

[MDB1056]

Carbs are actually pretty easy and inexpensive to rebuild, and plenty of places for high quality kits and instructions. I highly recommend doing it yourself vs buying a whole new carb. That's a lot of gas money......

[Jetsetr]

If it was a Rochester Quadrajet I would tell you shit can it and get a Holley! Have a Edelbrock (Carter) 1409 on the SBC in the Malibu. It sat for 4+ years and I just changed the accelerator pump and it runs perfect (another simple carb to work on)...

[Wayne]

@GaryWilkinson when you rebuilt the carburetor did you compare the old gaskets to the new ones in the rebuild kit? Holly had a few gasket designs and the rebuild kits usually include a few different ones that look similar. Every little hole matters.

 

Having non adjustable float bowls is not a big deal. If the carb has plastic floats you can’t adjust float level. You need the metal floats so you can bend the float arm. Typically if you hold a float bowl upside down and look at the flat part on the float. If the flat part of the float is parallel to the inside wall of the float bowl your good to go.

 

For how much crap was on the ground and your description of the idle it would have to be running very rich. The little 180 degree tubes on the top of the carb are the bowl vents. Was any fuel coming out of them? If a float is stuck causing the needle and seat to be open, fuel will some times come out of the bowl vent tubes.

 

The behavior you are describing can also be from a blown or leaking power valve.

 

I highly recommend getting reusable bowl and metering block gaskets. Summit Racing or Jegs carries kits from Moroso which are much better than the blue Holly gaskets. You can also “make” the standard gaskets into reusable by using rubbing alcohol to remove the glue and then spray the gaskets with Pam cooking spray. However I wouldn’t recommend doing that unless you have some spare gaskets to learn on.

 

Not sure where you live, if you were local I would help you go through the carb again to be sure there are no issues with it.

[Wayne]

Should have made a clarification on the plastic floats, they are non-adjustable unless you have the threaded needle and seat assembly that was pictured. Also the plastic covering the needle and seat assembly slides out of the bowl if needed.

 

The plastic floats can also deteriorate over time and become “water logged” with fuel so the don’t float properly. I’ve never seen that personally but it’s stated in all of the Holly performance books I have.

[MDB1056]

@Jetsetr have to disagree on Quadrajet. Great carb, super easy to work on and rebuild, easier than Holly. Like all brands they all have followings. I know many who label Qjets as one of the best ever made. I’m a fan of both.

[Jetsetr]

@Wayne The pics of the internal float bowl assembly was from my 4160 with the adjustable floats. Was just showing the OP what’s inside. If I remember the non adjustable floats are a bit different, with a “arm” that you bend to adjust the level. Great tips on the power valve and vent tubes. That was a LOT of fuel to make a mess like that!

 

@MDB1056 Never had much luck with Q-Jets...lot of people do REALLY like them though...

[GaryWilkinson]

@Jetsetr @Orlando76 Thanks so much for the help guys. Truly great of you to take the time.

 

Few points: mechanic is a marine engine mechanic, that’s where it is now but he won’t get to it for probably 10 days. I trust him, knows his stuff. BUT I may go there this weekend and at least take some pics for myself and this thread.

 

I wasn’t there when my cousin did the carb kit. He knows engines pretty well but yes, could have made an error of course.

 

Ignition is stock, plugs, points etc. Tried a few years back to use upgraded wires ((Accell?) and ran poorly, went back to stock wires.

 

When the idle and general performance gradually deteriorated last season I admit I didn’t think of ignition components. Probably should have swapped out wires, point, condenser first instead of this world of hurt I find myself in. And yes, our season is very short, 2 1/2 - 3 months, most of it in wetsuits.

 

Ya Dave, you have to be really careful on the fuel line nuts. A perfect fitting wrench is the only way to go. In fact I’m going to check that it wasn’t cross threaded! (gasp)

 

The minimum will be to go to the boat in my mechanics years and take some pics with the bowls off. Hopefully I won’t need new gaskets to do just that.

 

What do you think about switching the bowls to external adjustment capability?

 

Thanks again for the help and tic, tic, tic. I can hear the season moving along goddammit.

 

 

[Jetsetr]

I swapped fixed to adjustable on a MC S&S...made getting float height set a lot easier with the non level carb in the earlier boats. We had an issue with fuel just dripping thru the Venturi causing a little bit rich condition @ idle, and after a while the engine would load up. However, removing the float bowl really isn’t that big of a deal for fine tuning the float. Like Wayne said if you turn it upside down and the float is level that’s going to get you pretty close. I think you have something stuck in the needle or a bad float for as much fuel that was going thru.

[Jetsetr]

Didn’t forget the needle???

[MDB1056]

@GaryWilkinson - Can't still have points ignition as noted earlier post you said "point". Assuming it's electronic ignition since a 95. Really hate to see you without for another 2+ weeks. I'd recommend you put the carb on the workbench (or kitchen table) and take apart and reassemble in an afternoon and be back on the water. It's really not scary at all....

[GaryWilkinson]

@MDB1056 ya believe it or not, it’s points ignition. Distributor cap, rotor, condenser etc. It’s all there.

 

I’m going to have another go at it this weekend.

 

Found this on the web also.

This with your collective advice above Will get me going hopefully.

 

GENERAL GUIDELINES FOR

ADJUSTING BRASS AND

NITROPHYL FLOATS

Two methods of float adjustment are provided for with Holley

performance carburetors depending on the style of float bowl

and needle and seat assembly employed. They are the inter-

nal (dry) setting and the external (wet) setting. The internal

float adjustment is accomplished with the fuel bowl off the

carburetor. With “internally adjustable” needle and seats, the

fuel bowl is inverted and the float tang, or tab, is adjusted to

the point where the float surface is parallel to the fuel bowl

surface, just underneath. An initial dry setting can also be

accomplished with “externally adjustable” needle and seats.

To achieve this, invert the fuel bowl and turn the adjusting nut

until the float surface lies parallel to the fuel bowl casting

surface underneath.

Another, more accurate adjustment can be made with the

side hung style float if measuring gauges, such as drill bits,

are available. Here, with the fuel bowl inverted, the primary

float can be adjusted to the point where there is a 7/64" gap

between the “toe” of the float and the bottom of the fuel bowl

surface underneath. The float “toe” is the part of the float fur-

thest from where the arm is attached. The secondary float

can be adjusted to the point where there is a 13/64" gap

between the “heel” of the float and the bottom of the fuel

bowl surface underneath. The float “heel” is the part of the

float closest to the point where the arm is attached.

A “wet” level float adjustment can be performed on either the

side or center hung floats, if the fuel bowls have provision for

the externally adjustable needle and seats. This adjustment is

made as follows. Start the vehicle up and move it out of the

garage and into an open area where plenty of fresh ventila-

tion is available. Allow the idle to stabilize. Turn the engine

off and remove the sight plug from the primary fuel bowl to

inspect the fuel level. If it’s been determined that adjustment is

required use a large screw driver to crack loose the lock

screw. With a 5/8" open-end wrench turn the adjusting nut

clockwise to lower the float level.

Conversely, turn the adjusting nut counter-clockwise to raise

the float level. Tighten the lock screw. Restart the vehicle and

let the engine idle stabilize. Shut the engine off. Remove the

sight plug to reinspect the fuel level. The fuel level should sta-

bilize at just below the level of the fuel bowl sight plug hole.

ADJUSTING DURACON (PLASTIC)

FLOATS

The Duracon float rides higher on the fuel than either the

brass or nitrophyl float and, therefore, a higher setting is in

order. A Duracon float, set at the same level as either a brass

or nitrophyl float, would make the carburetor run leaner,

everything else being equal. This is because there would be

less fuel available in the fuel bowl. The Duracon float setting

must be higher to compensate for this condition.

Dry Setting for Duracon Center Hung Float:

The primary side setting is .3125" (5/16"), measured with

the fuel bowl inverted, at the middle of the float. The second-

ary side setting is .3750" (3/8"), measured with the fuel

bowl inverted, at the middle of the float (back side).

Dry Setting for Duracon Side Hung Float:

The primary side setting is .2188" (7/32"), measured with

the fuel bowl inverted, at the toe of the float. The secondary

side setting is .3125" (5/16"), measured with the fuel bowl

inverted, at the toe of the float.

Wet Setting for Duracon Float:

Refer to “Wet Float Setting”, discussed previously.

 

[BraceMaker]

@GaryWilkinson - WILD I had thought that starting in 91 SN had gone to those funky electronic distributors protec?

 

[Orlando76]

@BraceMaker Protec was 92-94. Possibly 91. Then the went back to conventional distributors after that.

[BraceMaker]

@Orlando76 and by conventional - breaker ignitions?

[Orlando76]

Conventional: While this is called a “conventional” ignition system, it’s something of a misnomer. These are not used on modern cars, at least not in the US. This is an older style of ignition system that uses points, a distributor, and an external coil. They’re high-maintenance, but easily fixed and pretty cheap. Service intervals ranged from every 5,000 to 10,000 miles.

 

Electronic: An electronic ignition is a modification on the conventional system, and you’ll find these in widespread use today, although distributor-less systems are now becoming more common. In an electronic system, you still have a distributor, but the points have been replaced with a pickup coil, and there’s an electronic ignition control module. These are far less likely to breakdown than conventional systems, and provide very reliable operation. Service intervals on these types of systems are generally recommended every 25,000 miles or so.

 

@BraceMaker

[BraceMaker]

Ok we're on the same page I usually refer to electronic systems that replace a points set up with a hall effect sensor or similar while still in a mechanical advance distributor as a "breakerless ignition" as opposed to an electronic ignition and haven't referred to a points as conventional for the same reason as referenced I'm not sure the guy who changes my oil knows how to use a feeler gauge or dwell meter.

 

I use that nomenclature as I do not love breakerless conversions of conventional distributors but do like HEI conversions.

[Orlando76]

They all have improved. Module failures on conversion kits have gone down from what I’ve gathered tremendously... but, It’s hard to beat a clean 1 wire installation of a DUI. For some reason when you throw a ballast resistor in the equation people go brain dead.

 

 

[GaryWilkinson]

@Orlando76 would you recommend converting to electronic? I believe the kits keep the housing, sort of for the distributor, but the top end is electronic, no cap, rotor, condenser etc.

 

What do you think?

 

Back to my PDF and your posts to work on the carb this Saturday.

First thing is to remove the barrels, see what type it is, see if the floats are “gas-logged” and try and adjust them.

 

I shall take pix and report what I find.

[Orlando76]

You still have a rotor and cap for the with the conversion. But id keep points and condenser. If it ain’t broke, don’t fix it. No performance gains in our application. If you had rusty springs and sloppy distributor and it wasn’t advancing properly, then I’d entertain a DUI.

 

Only problem I ever had with points was moisture would build up on contact surface. If I’d let the boat sit for a a few days I had to pull dizzy cap off and prop motor box up to let ventilate. Eventually that dizzy broke and I put a new one in, never pulled cap since but I always maintained propping motorbox up to let that moisture escape from bilge.

 

I just copy and pasted the entire previous post stating “Conventional distributors are high maintenance” bc felt like Bracemaker and I weren’t on same page. The high maintenance statement I didn’t agree with, not for our application.

[LeonL]

Only other tip. If the O rings on the transfer tube fit properly (should since your cousin put a new kit in) just barely start them, insert carefully and they wil roll a full 360 and seat.

[Orlando76]

How did you do? Sorry I missed your pm over the weekend.

[GaryWilkinson]

@Orlando76 after hearing from a few experts and kind people like yourselves, I dove in deep and bought a new carb.

 

It seems the 10+ years or so of running less than premium gas that contains ethanol corroded the castings, ports and hard parts of the carb beyond anything a rebuild could fix.

 

I ordered it Monday, got it Tuesday! From SkiDim (fantastic people and service) mechanic put it on yesterday and called to say it’s ready. ??

 

Thanks again for your help.

 

So it’s premium gas from now on, you guys hear the same? (Avoid ethanol for our boats?)

 

[vtmecheng]

Ethanol is horrible on carbs and goes bad quickly. That's why many marinas have ethanol free gas.

[Jetsetr]

I will take the old carb if you’re going to toss it....will pay shipping...

Glad you have it back in service.

[DW]

@GaryWilkinson - glad you solved your carb issue, make sure that the gas you choose is ethanol free if that is what you are wanting. The premium fuel may be ethanol spiked and given your compression ratio, doubtful you need it for the higher octane. You might want to consider changing the fuel supply lines if you have not done that already as debris could get in the new carb from them.

[Orlando76]

I’m on the fence with ethanol. I hadn’t run any E-free in my Ski Nautiques in about 6 years.... knock on wood, no problems. In my Honda outboard I seem to run e free one year, ethanol the next. I hadn’t really noticed a difference in it, carb’s need gone through every 366 days no matter what. You aren’t running high enough compression for anything other than 87 oct.

 

And to summarize myself on about the 3rd comment on this thread about a month ago... most guys will disagree with me but don’t bother rebuilding carb’s. Spend the $700 or so, buy a brand new one calibrated for a Ford, bolt it on and ski within the hour. The money spent upfront will save money, time, and aggravation later. Season is too short, Go Ski!!!

[vtmecheng]

Just my opinion but I think ethanol is probably ok if you don't let it sit around for too long. Switch to e-free near the end of the season or if you know the boat will sit for some time. That's what my family has done for years and the carb seems to make it about 8 years between minor rebuilds.

[MDB1056]

@orlando76 for about $50 or so for a carb kit that’s $650 more for gas, gear, etc. Rebuilding is really pretty simple .

[steve97tj]

Bumping an older thread as this came up when I was trying to figure out my problem.

 

I have a 96 ski brendella sport comp open bow with the PCM 5.8 ho with Holley 4160 fueling it, 80456-1 is the list #.

 

I’ve continued to have issues with it in my short time of owning it, which has made me understand 4-bbl carbs more and more each time I go out.

 

Can I swap the bowls to the center hung externally adjustable bowls, getting the secondary bowl that’s for a vacuum secondary?

[Wayne]

@steve97tj you can but I would recommend getting side hung adjustable float bowls over center hung for a marine application. Side hung float bowls are less susceptible to the effects from bow rise/fall.

 

With center hung float bowls, the rear bowl has a tendency to over flow when taking off due to the way the fuel sloshes in conjunction with the bow rising.

 

 

[steve97tj]

@Wayne That’s essentially the answer I was looking for. I keep trying to find out why the 4160 marine has certain things that are different then a regular carb. I’ve had to learn about 4bbl carbs bc of this boat. I have a better understanding of how and what things do but still trying to iron out the tuning.

 

Reason I was looking into this in first place, I live 45-1.5hrs from the two lakes we frequent and had ignition and carb issues the several times I was able to take it out this summer, ran great in my driveway but crap once in the water. Last time out It ran so rich, fouled plugs and left be stranded in the cove of boat ramp. I had just rebuilt it and the floats were set what I thought were correct but after having the issue I figured they were out.

 

I winterized it recently and when running it in my driveway, the 2 screws on side of carb had no affect or change when I turned them all the way in or when screwing them out, which makes me believe the primary circuit has issue, listening to it I was guessing the float was probably not adjusted right and it was bypassing sucking fuel. I never took the spark arrest off but I have had issue with fuel dripping in the past. I hadn’t touched it since August as time hadn’t allowed and just gotten frustrated with it.

[Wayne]

@steve97tj all of my carburetor experience is with Holley and I’ve used the 4160 on several vehicles.

 

A few things I’ve learned over the years about Holley.

 

Replace the metering block and float bowl gaskets with the reusable kind from Moroso or a similar aftermarket company. It’s makes working on them so much easier.

 

Clean every little orifice with carb cleaner when you have it apart. The smallest piece of debris can cause crazy issues. Also make sure you have a good fuel filter in place. On cars I would pull out the little brass filters Holley puts on some float bowls but on marine applications I always left them in.

 

If you don’t have externally adjustable float bowls, add them. I always started with the floats so if I flipped the bowl upside down the top of the float was parallel to the top of the bowl. This is just a starting point and need to adjust from there with the carb installed as it would be under normal operation (in this case try to note the attitude of the boat in the water when in neutral, you can always uncouple your trailer and use the tongue jack to set the level).

 

If the carb was tuned correctly and then you started to have issues of it running rich there are 3 things that cause this on a Holley.

 

1) Debris in a metering circuit

2) Excessively high float level or a stuck open float needle and seat.

3) Blown/damaged power valve

 

All of the above can cause the idle metering screws to be non-responsive but so can a vacuum leak. I’ve missed capping a vacuum port on the base plate a few times on a rebuild and it’s thrown me off a few times. However a vacuum leak usually causes a lean idle condition and high idle but you can compensate the idle its adjustment screw and then you will be chasing your tail unless you can hear the leak.