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Dual to Single Carb Conversion AQ151C

"E.P. and others,

I've

"E.P. and others,

I've been watching this Weber Carb swap discussion for some time now. There was a guy who did his own version with a friend building the adapter last year. It sounded like he was well pleased with the outcome.

Here's where I'm at on my project. I'm almost ready to do sea trials on a total restoration project on a 17-1/2' Campion (former hardtop that now has a mini-cuddy about 2' forward for more deck space aft).
Long story short the motor is an AQ140 now temporarily converted to a single Solex downdraft with matching VP manifold. Making it, in effect an AQ125A with an oil cooler.
A machinist friend set up a CAD/CAM program and machined an excellent aluminum adapter to match my rebuilt Weber 32/36 DFAV carb to the factory manifold (The Weber is jetted for the same size--in CC's-- but for an Automotive application). It will have the flame arrestor and tube from fuel pump, etc..

I'm hoping that if I set this up right, the boat can run on the primary 32mm most of the time and only kick in the secondary 36mm when I need an extra boost for a straight run out and back to a fishing site. That's the plan. Hopefully this should squeeze a little extra out of each gallon of gas. We will see as it progresses.

Any further insight concerning making up some Push/Pull linkage that sits near the carb would be appreciated. My cable extends out when the throttle control is pushed forward and it needs to pull down or back to open the throttle on the little (temp) Solex OR the Weber replacement. I've got a pretty good plan for my homebuilt linkage version, but always open to better ways to do it."
 
"I don't know what make yo

"I don't know what make your throttle cable is Dennis but the dealer tells me that I can convert my Morris cable to either push or pull and that is done via the linkage at the throttle handle. I was going to attempt that but with the bracket and bell crank I'm getting from Weber it won't be necessary (I hope).

Weber may come up with a box to fit over the two solex carb ports to carry a single Weber 2bbl carb, so they say. That would be a less expensive conversion than the carb/manifold option.
fwiw, Tom"
 
"I have an Aq145A with the twi

"I have an Aq145A with the twin Solex carbs. Seems like I always have some kind of issue, a needle will stick, they get out of sync, sometimes stall when docking (motor is in my houseboat so stalling around the dock is not good) then start hard right after,sometimes a minutes or so. Have to warm it up for 10 minutes or so before I even think about leaving the buoy. The mechanic at our Marina is against putting anything other than Volvo original equipment in these old motors and wasnt in favor of the Weber conversion but after reading the posts on the subject it sounds like that will solve most if not all my problems that appear to be fuel related."
 
"Don't forget about conver

"Don't forget about converting the distributor to electronic (Pertronix or HotSpark), that will solve many of the common ignition problems."
 
"Just wondering how the Weber

"Just wondering how the Weber worked out. Do you have it running yet. If so what are the results?

Have a great day,

Rob"
 
"The Weber is on the engine an

"The Weber is on the engine and it runs, however, I discovered that the raw water pump gasket is leaking and that will have to be replaced before I can tinker with the carb. Pictures to follow.

Tom"
 
"Does anyone know if the weber

"Does anyone know if the weber kit makes the carb sit higher than origional? I have a Tiara 2500 with twin Aq140's in the floor, and there isn't any room for a tall carb or gumpy flame arrestor once you put the floor covers on. Any one have pics of this kit mounted? I need to know before I order mine. If the carb or flame arrestor sits higher than the valve cover it'll be too high."
 
"Here are the first three pict

"Here are the first three pictures; I have a couple more and I'll try to get them on another post.

http://tinypic.com/view.php?pic=io3jad&s=4
http://tinypic.com/view.php?pic=jikqv8&s=4
http://tinypic.com/view.php?pic=303h4p3&s=4

the first pic is the base, pulleys and pushrods available from Weber. They make for a smooth operation.

The second shows the height of the installation and it fits easily under my engine coop.

The third one is a but blurry; it is a picture of the bracket I made and it is attached at the original throttle attachment on the block."
 
"Here are the next two picture

"Here are the next two pictures.

http://tinypic.com/view.php?pic=331p2zp&s=4
http://tinypic.com/view.php?pic=2s7fc5s&s=4

These two are of the general assembly showing the throttle connections.

NOTE: When I first started the engine it ran very rich and I could not get it adjusted. After I had turned the idle screws ALL the way in and the engine continued to run, I twigged that the electric choke was still on. I changed the choke power source from the oil pressure sender to the +ve side of the coil and that cured the problem. A little more tweaking and I should be in business.

Tom"
 
"Hi Tom,

Anxiously waiting

"Hi Tom,

Anxiously waiting for the performance update. How is it running with the new carb? Is it worthwhile?

Have a great day,

Rob."
 
"The first sea trial was a bus

"The first sea trial was a bust, very rich and bogging at higher throttle settings. I've had issues with vacuum leaks (I think now solved) and my ignition timing is acting up so it is difficult to get the carb adjustments set right. I'll check out the timing today and if it is still acting up I'll change out the Hot Spark for the Pertroncis and clean the counter-weights to see if that corrects the timing wander.

I'm getting great support from Weber (private phone # for after hours questions). They will walk me through changing jets, adjusting float level if required."
 
"That is good to hear that you

"That is good to hear that you are making progress and that you are getting good support from Weber. Hopefully your next sea-trial will be a success.

Good luck and have a great day,

Rob."
 
"Another thought, spray carb c

"Another thought, spray carb cleaner around all the gasket points where you can have vacuum leaks. Change in engine rpm = vacuum leak, no change = no vacuum leak. Easy way to find leaks.

Have a great day,

Rob."
 
"I finally plugged all vacuum

"I finally plugged all vacuum leaks and got the timing to behave so I took it (Malibu 18.5) out for another sea trial. I do not yet have the carb low rpm circuit spot on but it holds rpm under load.

I set my new trim tabs to 'bow down' and advanced the throttle. This boat has never reacted like that. I'll bet it was on the plane in 5 boat lengths. The RPMs ran up smooth as silk. I never did get to wot; at 3400 rpm the boat held the plane and then some. Ran it for about 15 minutes and it never missed a beat; temps and pressures all great.

Although I have some issues with the fit of the intake manifold that I'll take up with Weber, the carb itself was never one of my problems. From what I've seen so far today, this conversion is going to be all I had hoped for and more.

Anyone want more information, email me and I'll put you on to the right people at Weber.

Tom"
 
"I have a 140A which has been

"I have a 140A which has been rebuilt but has yet to be fired-up. I would rather ditch the twin Solex downdraft carbs and intall a single carb as the Solex ones are trashed (I have 4 of these carbs). A while ago, I came across an adaptor on ebay (picture attached) which can be used on the single carb intake manifold in order to use a two barrel carb. Unfortunately, I cannot find the supplier of the adaptor as the ebay posting has been deleted. Does anyone in the Forum have any idea where I might find this adaptor? Although I'm aware of the Redline Weber conversion, the cost is too prohibitive. Your help would be greatly appreciated

216027.jpg
single barrel to two barrel adaptor
 
"Robert,

I just did a quick

"Robert,

I just did a quick search and found this website:

http://www.wpsracing.com/cpprcaad.html

They have a lot of adapters.

I had a machinist friend make up an adapter for an AQ 125A manifold that allows me to bolt on a little Weber 32/36. Early Pintos and Capris used some Webers (or "Holley-Webers" licensed to be built by Holley) for 2.0 and 2.3 liter motors. Be aware that you've got to use a flame arrestor, and a few other modes like the kits that Weber sells. With some "engine-newity" you can get it done for around 1/3 of the kit's cost."
 
"Dennis K.....thanks for the i

"Dennis K.....thanks for the info. Although WPS Racing does not have the adapter I was looking for, you encouraged me to continue looking. I finally found jameng.com who has a universal one barrel to two barrel adapter for $47.00. Their adapter looks exactly like the picture I previously posted. They are located in Monterey, CA.

Again, thanks for your help"
 
"Make sure you have enough ver

"Make sure you have enough vertical clearance to accommodate the height of the carb, flame arrester and the adapter. I know this has been an issue with some covered engine installations."
 
For Lee Stein or Harvey Freder

For Lee Stein or Harvey Frederick or anyone who has the Weber conversion installed.

What size idle jets have you installed? My carb came with the 50 jets and it idles a little rich. I just received the 45 jets and I'll try them tomorrow but I'd like to compare notes with other users.
 
"I just installed the 45 jets

"I just installed the 45 jets and they have leaned the idle to just right. The primary and secondary jets are about $4 each from Weber and it takes about 3 minutes to change them out, very simple. Then you just repeat the 'best lean idle mixture' routine. It is worth the couple of dollars as the leaner mix is better for the health of the engine.

The old engine has never run better and I cannot believe the power. I'm finished tinkering with it until the next thing breaks
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"
 
"Tom, if you don't stop po

"Tom, if you don't stop posting all the wonders that the Weber conversion has done to your 4 banger I think I will end approaching the guy who bought my previous boat from me and ask him if he is willing to sell it back, so that I can convert the AQ140 to Weber!!
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Boy, you are making me feel jealous.
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"
 
"After I get my motor (AQ

"After I get my motor (AQ 140A) back I'm going to install my Weber 32/36 DFAV. We'll know then how the little Weber PROGRESSIVE 2-barrels work on the older 4 cyl. Volvos. Hopefully about 2 weeks from now.
I'm convinced that starting these motors with non-choked carbs shortens their life. Having to pump the throttle and rev up the motor until it warms up can't be good. The Webers seem like an excellent solution to a smoother, longer running motor--plus more power and maybe better gas mileage.

E.P. GET YOUR BOAT BACK!
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...."
 
"ok do i have this right, i ha

"ok do i have this right, i have an aq110 with 2x zenith carbs, the b20 weber kit should fit???

thnaks tg"
 
"I've decided to bin my so

"I've decided to bin my solex carbs and replace them with the 38DGAS weber conversion. A quick question on the choke possibilities. I can get the carb with either a water, electric or manual choke. I think I'm discounting manual, since the cable run would be a pain, so the choice is electric or manual.

So far posters here have gone with the electric option, but how does this work? Do I need to wire up a control on the dash to activate the choke or does it work automatically somehow? I'm hoping to have the manifold and carb on Tuesday, so I'd like to get any other parts I might need before then.

Thanks,

Paul."
 
I just realized a benifit to t

I just realized a benifit to the kit that I never would have expected which made the kit THE best money I ever spent! My wife saw the reciept a told me she wants a divorce because I spend too much money. The boat is going to be much quieter now too.
Any single women want to go for a boat ride?
 
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