The Stovebolt Site Forums The Shop Area The HiPo Shop Newq guy here with a dual carbed 235

Hi guys, I'm new here, just bought my first true stovebolt... i used to have a '64 chevy II with a stock 194, but i just bought a '62 chevy LWB fleetside with a 235 (i assume, unless a 261 was available in '62, how can you tell?) it has a Edelbrock 2X1 intake, with 2 Rochester B's and a split header, dont know the brand. I'm having some issues with it, as far as a stumble off idle, and it runs rough while holding speed under 50 mph. any thoughts?

Welcome to the 'Bolt Jay.
Most liely, it is a 235. If you can get the #s by the distributor, that might help us decipher what it is.
On to your question., I'm going to suggest that you check the timing and/or that operation of the advance. I had a similar problem, especially at the lower rpm band, and found that I needed more advance. Also, check for vacuum leaks.
One more thing. You got any pix of them (I want to see them both!).

these are some pics of the truck
Dual Carbs

Side

Front

Welcome to the best site on the 'net for these ol trucks. Stick around,,youll learn alot.
It looks like theres some serious leaking going on with those carbs. Maybe a rebuild would help? Or a float adjustment.
Good Luck,
Marty

I'm pretty sure that's a 235. If it were a '62 261, it would have big 1/2" NPT oil hoses going out from behind those exhaust manifolds to a big oil filter, and it would have been painted green. However, check the casting numbers to be sure.

That looks like a pretty straight truck, for the age. I've got a 61 fleetside and it looks about the same , color and all. Of course the front grille and hood are different. I know on my 235 on the passenger side, the pushrod cover is one large cover. I believe the 216 has 2 separare covers, but not for sure. Casting #'s would take the geusswork out of it.

Cool, two 1 barrel carbs., I love it! Was that an option or is that an after-market package?

Aftermarket. GM did offer triples on a 235, but only on the '53-'55 (early) Corvette. Lots of us on here are running a similar setup, here's mine.http://rides.webshots.com/photo/2791114620092261295pSVaee
Now that I've seen a pic, I'm inclined to agree about a posible float/carb overhaul problem. I also notice the hose coming off the port on the manifold plugged with a screw(?). That could be a potential vacuum leak. Nothing major. Just needs a little TLC.

Well, that leak was the first thing I attended to... the 1/8" NPT fitting going into the carb as loose.. It seems the timing was my problem. it was too far advanced, as i noticed some pre-ignition knock when i loaded the engine down... backed the timing down a little, and she's doing pretty good now! the Blocked off vacuum hose has been removed and replaced with a pipe plug. Hopefully, I'm gonna get some glasspacks installed this week,, it already has duals, but it's got some el-cheapo super turbo mufflers poorly welded on, and it sounds like poo. Also need to change the waterpump, because it has a little slack in the bearings.

Glad you fixed the fuel leak, Nice looking truck I have a 62 also.Welcome aboard Jay.

Jay,

If you still want to know what engine you have, either post the number that is pressed into the block to the rear of the distributor or post the block casting code (I think it is behind the upper right of the starter - maybe someone else can give the location).

The valve cover is from a 59-62 passenger car but it could have been placed on any 54-62 235/261. The 54-62 side cover (push-rod cover) on 235s/261s did not extend over the spark plugs or above the block (it also did not extend above the block on 50-53 235s but yours is not an older 235).

As stated by 4ontheFloor, a 58-62 261 would have 1/2" NPT holes for an oil filter. Can you get us a clearer/closer picture of the oil line holes at the lower right of the manifold side of the block?

The engine color is not a good indicator because many people re-painted 216/235/261 engines that passenger-car blue color (most 261 were green but some were yellow).

Those Rochester carbs (which I like for originality) are jokingly called "leak-chesters" because they commonly leaked at the top-to-bottom joint. There are other things that can cause leaks - it looks like your might also have worn holes where the throttle valve pivots in the body.

Nice looking truck. That engine and carb set-up is a nice conversation piece and far more interesting than putting a modern engine in that engine bay.

Tim

Ditto on the "Welcome" Jay!! Looks like you've got a nice clean truck right from the gitgo!!! As Tim pointed out, the block casting numbers under and between the road draft tube and the fuel pump should help you lock in on the year of the engine.

Speaking of fuel pumps....I along with others have worked on solutions to the "leaking Rochesters" issue. Some of us have "jumped ship" and gone with Carter/Weber progressive 2 bbls. on our dual setups and some (the faithful) have stayed with their original equipment. One common thread that I've noted is that regardless of the type carb you're running, the addition of a fuel pressure regulator and a mini pressure gauge (from your local auto parts store) that adjusts the stock GM pump down to 3.5 psi cures the fuel dumping problem. No, it's not going to make a dirty carb in need of cleaning and a kit stop leaking, but it will improve your chances of salvaging the original equipment and driving with an engine that idles and accelerates without hesitation.

If you do a "search" of carb options, repairs and upgrades you'll see how others have cured the problem and get to enjoy their trucks as economical and fun drivers.

Once again, Welcome aboard!!!

Dave

Ok... an update, Today i removed the 2 super turbo mufflers and I'm just running straight pipes now... this thing is 3x as loud ad my old nova, i used to have straight pipes on it... is really raspy.... definately sounds a little meaner... is this because of the split header? or do i posibly have some other stuff done to this engine that i dont know of? or is the 235 just that much louder than the later model 194's/230's ??

The original mufflers for trucks were straight thru(I believe steel pack?) that sound very good as duals with larger than stock pipes. I heard one not too long ago and preferred the sound over my stainless dual in/dual out Bazani.
When I installed my headers, I drove it from my house to the exhaust shop with no pipes. That was the coolest sound ever under 2000 rpms. Anything over that was way too much to take for an extended period. Kinda like standing directly behind 2 phat, high revving Harleys.

It also appears that your intake is not heated. It is debatable here, but many including myself will agree that that it is essential for smooth consistent idle and better mileage as well. It's not AS important in warmer climates, but important nonetheless.
I have fentons, and my stock intake (as well as my future 2x1 intake) is water heated. Do a search on intake heat and you will find a lot of info. Good luck and Cheers! Matt

Welcome to the Bolt. It's good to have new blood here on the HiPo .