The Stovebolt Site Forums The Shop Area Engine Shop 216 Engine Carb Advice

Since I got the 1953 Chevy I have notice that when I start it I get a lot of black thrown crud out the tail pipe when It first start it up. Also when parked and idling I get black deposits on the ground. My friend followed me home and say he could see puff of black smoke at the gear changes. The truck start very easily and I don’t think it would even need choke when cold is 2 C here. I check the plugs and the are covered in black soot, not oil black soot.

I think it’s probably over fuelling for some reason. Could be stuck float, but don’t really know the causes of such problems. I have ordered a rebuild kit from ebay for the 216 single barrel Rochester carburettor and plan to try rebuilding it. I have never opened up a carburettor and a little bit daunted at the idea.

I noticed I can get a replacement carb from classic parts but it carries this warning:

Rebuilt Rochester 1 barrel type only. This is a rebuilt carburettor and we will need a good core to have it rebuilt. Mounting bolt to bolt center measurement is 2 3/4" . Price does not include a $100.00 Core charge. **All carburettor cores that are returned have to be just like the one in the picture and no carbs with a choke.** **DO NOT USE ETHENOL FUEL AS THESE OLDER CARBS OVER TIME WILL NOT WORK OR PERFORM AS ORIGINAL**

My understanding is that all fuel in the UK now contains ethanol so wasn’t sure how to proceed with this.

Heard a few people mentioning using a Carter carburettor with electric choke. Most appear to be fitting these to the 235 engine rather than the 216 that i own.

So as usual just look for some general advice of how to proceed with investigating the problem, Carb rebuild or replacement options.

I have to say I am a very lazy mechanic so if there is an easy fix that just involves throwing some money at the problem that’s probably my preferred solution.

Please could you give me some thought ideas etc on how to proceed.


Thanks in advance for any comments and advice

Chris

Watch this video to see how easy it is to rebuild it:

Hello Gord

Thanks for the video link. I do admit to watching that previously and it has a lot to do with why I would rather just replace the carb with one that has already been rebuilt. It just looks like there a lot that can go wrong In the rebuild process and getting the parts together etc. I do have a rebuild kit on order but not sure how good it is.


I may just lift the carb of the manifold to see if it’s leaking fuel. I guess I should also check idle mixture screw

But thank you for the information

Regards Chris

When you take the carb off, look for a gasket between the carb and the intake manifold. I think that its a common error to install a gasket that blocks the vacuum port on the base of the carb. This vacuum port is for the power piston and a stuck power piston may be your problem. Carb kits come with this gasket - just because the kit includes the gasket it doesn't mean it should be used.

I suppose that there are garages in your area that could rebuild your carb. You could hand them the carb and the kit and let them do it. If it takes them more than an hour (not including soaking time), they don't know any more than you do. Don't give it to the guys at the Lazy Boy Garage!

If you DIY, I think that the biggest confusion is keeping track of the (5, I think) springs. Take some pictures as you disassemble the carb. The instructions sheet and the video are not really helpful in pointing out which spring goes where. It's mainly common sense where the springs go, but I trust pictures more than common sense and memory.

I would think that if you don't have gas leaking out at the bottom, which is easily seen, your problem is quite likely the power valve. As mentioned above, the wrong gasket under the carb can cause this. there is a little hole in the base flange that must receive vacuum.

Half of the "rebuilt" carbs you get any more are not good. It is best to repair yours or get someone that can. There is a lot of info & help on this website to help you through it.
George

Thanks for all the support. I wouldn’t trust it to any of the local garages as they won’t have seen a carburettor in years. I may see if I can find a carburettor rebuild specialist. I guessing it may be worth paying a little to get it ultrasonic cleaned as part of the rebuild. As you also say we live in modern age with digital photography and video. I have been making a video journal of my restoration and I’m sure you guys will talk me through any problems as you have advised and supported me in the past.

Thanks again regards Chris

Just don't mention the R word. If you want to throw money at it.

Chris - you asked about the carburetor (US spelling ) so all of your answers have been about the carburetor. And yes, it is quite easy to "throw rocks" at the Rochester B.

However:

A perfect (generally not a term one would use with the Rochester B ) carburetor coupled with a defective ignition system or poor compression will cause a very rich condition.

So, a suggestion:

Prior to rebuilding the carburetor, first make sure you do not have an electric fuel pump, then do both a compression test, and a comprehensive ignition test.

ONE TEST IS WORTH 1000 OPINIONS!

If both the compression test is normal, and the ignition is good, then look at the carb.

When new, the Rochester B tended to be slightly lean, with a slight bog or hesitation often occuring. As ethanol has less energy content, this condition is worsened by the use of ethanol fuel.

Over time, the Rochester B goes from slightly lean to very rich. This, as mentioned above, may be caused by a stuck power valve. But it may also be caused by warped castings. And, as mentioned above, the incorrect mounting gasket will cause the power valve to always be open from the moment the carburetor is installed.

Ethanol DOES do long term damage, but we are talking about decades, not months or years. Over a couple of decades, the ethanol can cause holes to form in the bottom of the zinc alloy fuel bowl. Again, very long term, not short term. Short term damage would be to a neopreme accelerator pump. For some reason, neopreme after being in ethanol and then allowed to dry out, will turn hard. As an accelerator pump must flex to function, this issue can cause the accelerator pump to cease to function. This is generally not an issue with a vehicle that is driven daily, as the accelerator pump never dries out. The really good rebuilding kits have leather accelerator pumps that eliminate this issue.

You mentioned a possible switch to a Carter. The replacement Carter's are a type YF which has a diaphragm style accelerator pump (also neopreme), so is subject to the same issue. Vehicles that are driven daily tend to have a lot fewer issues. Carter YF's in both hot air choke and manual choke are available for the 216. Since the YF uses a diaphragm, leather is not possible.

Another possibility which solves the ethanol issue is the older Carter W-1 used on Chevrolet up through 1949. The bowl is cast iron, so no porosity issues; the pump is leather, so no pump failure issues. Should you opt to go this route, look for either a Carter W-1 483s or Carter W-1 574s.

The Rochester B gets a lot of bad press (mostly well-deserved), but make sure that it is the problem. Even a Carter W-1 with a defective ignition or poor compression will run rich!

Jon.

Hi Jon

Your post makes perfect sense as the whole engine is a bit of an unknown so your idea of doing some basic compression test is dead right. I’m hoping the compression will be good as the last owner did a rebuild but then again much of the things I have found has not been so good.

I just replaced the electric facet pump with a new Delco mechanical pump, As the truck broke down on its first outing. It wouldn’t go up hill as soon as the throttle was open to climb the hill the engine would just die. After replacing the pump and very dirty filter it runs better. However on the second trip out it broke down again. This time weak spark. The coil felt hotter than the engine block so figured it could be breaking down. I replaced the coil and it fired right up. The car has a pertronic igniter and a pertronic coil that failed both these looked like new. Just bought a new pertronic coil and will fit it this weekend.

The engine does start in half a crank every time so hoping that is a good sign for compression

I don’t think the smoke is related to the pump or recent ignition problems as it been doing it since I bought the truck last September. However only actually been out in it twice as it was winter and had a lot of other jobs to do on it.

If you fancy watching me panic having not driven a manual transmission in 20 years and then breaking down here is a link to my first road trip Video



Thanks again to everyone that has offered advice. I will keep you updated on progress with the truck here in the not so sunny UK

Regards Chris

Chris - since you have the electronic whizbang, have you upgraded to an alternator?

We have had lots of customers with "carburetor idle issues" and a ew with no alternator. The generator does not provide a significantly stable voltage at idle. Generally, the problem (running rich) goes away when the engine gets above maybe a 1000 RPM.

Jon.

Hello Jon

Yes I have fitted a modern alternator

Regards Chris

Interesting that this has come up. I was just searching for a w-1. You mentioned that the truck hasn't been run much, so some of the issue may be that it needs to be on the road a little more. The compression check will tell you some good things and most likely ease your mind some on the previous owners rebuild. I am a died in the wool fan of the carter YF. It solved many of my issues with the rochester -b. They have suddenly become a lot more expensive on e-bay though.

Chris, NICE truck with all the great original sounds. After watching your vid and reading the above I've no doubt you'll have it all properly sorted very soon. We have many knowledgeable gentlemen here that give good advise. The only thing I'd change on your truck (aside from the fuel pump and perhaps carb) is the air cleaner. I personally like the original oil bath units, either converted to paper filters or just leave em totally original. But, lots of options to get a larger/better filter on your truck.

Good Luck,
RonR

Hi Chris,
Different Jon here. If you want to see the work/study on the warped Rochester castings, you might search using "straightening Rochester castings". Based on what I saw, every Rochester B or BC will have a warped casting to one degree or another. There is also some information on the power circuit/power piston and the problems caused by loss of vacuum, inadequate vacuum, etc to that part of the carburetor and the effect it will have on the rich/lean condition.

The Carter I'm using on my 235 does run much leaner and more well mannered than the Rochester did by the way.

Anyone use a Carter carb on a 261? Thoughts?

Carter was the original equipment carb on Chevy engines for a long time until GM started to build their own carburetors in the early 1950's. I believe a Carter YF for a 258 cubic inch International/AMC/Jeep 6 cylinder engine would be just about perfect for a 261, or maybe the same carb set up for a 300 cubic inch Ford six, which would run slightly leaner than the AMC carb when used on a 261.
Jerry

anybody know the last year the w-1 was used?

1949 - passenger
1950 - truck

Thanks Carbking

Hello All just wanted to thank you all again. I just bought an ultrasonic cleaner to do the carb plus some of the other vintage gear I tinker with. I don’t think I will be doing the carb this weekend. My list of things to do this weekend are to replace the radiator and water pump and fit a new coil. My pertronic coil failed last weekend when I broke down again.

I’m doing the water pump because you may have heard it squealing in my video. Previous owner installed a new pump but with the wrong side pulley.

Decided not to get stressed over the running problems. It’s a long term project. My guilty secret is I enjoy working on them more than driving.


Regards Chris

Mike - the last W-1 most would be familiar with would be the 684s, used on 1949 passenger, 1949 truck, and some 1950 truck.

However, the very last W-1 was the 747s which was used by the US military on a Chevrolet 1 1/2 military only truck. This truck has a 235 CID engine.

Jon.

Jon,

Thanks for the additional info. I have a couple 216's I am considering freshening up and I am out of carter yf's. (makes it sound like I do this a lot) and was thinking about using W-1's. Both had rochesters and both later than 1950. Did the 747 have a larger throat, base and manifold for a 235 or were the changes only internally to the engine?

Mike - I Have never seen one of the 747s. Too lazy to search the microfilm for a print. GUESSING, since the 235 truck engines in the late 1940's used the passenger carb, that the 747s was the same.

Carter DID make a type W-2 carburetor with the large throttle body. Good luck on finding one!

Jon.

A quest for the holy grail!

Thanks for the info and the new obsession!

You might want to look at the Carter 965s I just listed in the "parts for sale" section. Another episode of "The Carburetor Detective" but with a good ending this time I believe.

Mike - check this out:

[img]http://www.thecarburetorshop.com/Carter_W2_1.jpg[/img]

Jon

Jon, is this one of yours? It is tempting!

Mike, yes, it is mine, not currently for sale. In 45 years of searching, I have found only 3.

Jon.