I am having a problem with the idle on my 235. I did a complete tune up including valve adjustment intakes at .006 exausts at.018. New plugs gapped to .035, points at .019. Also rebuilt the carb. carter type yf one barrel. I have run the truck for couple hundred miles without any problems and it runs very good. All of a sudden after running the truck until it is warm it does not want to idle. This does not seem to happen all the time but only occassionally. I can adjust the carb and get it idling rite but then the next time i drive it It will be idling to high. When I adjust the carb to bring down the idle drive it for A while then it will start not wanting to idle again. I have not checked the timing. Any ideas? Thanks
Look at the bakelite insulator block under the carby ~ they often get tiny cracks , once you touch it , it'll crumble stranding the truck until you buy a new one... Intake manifold to head joints might be loose too .
Thanks Nate I will check it out and let you know. Glad to here you are alright. Although I have never met you I feel like I know you from reading all your archived post. The information I have gotten from you and this site has been very helpful in getting my old truck going. Thanks again
Anytime ! Most of the best part of my life has been spent under a hood ya know Just remember : my advice is free and worth maybe 1/2 that . I forgot to mention , you're truck looks good . I assume you've allready checked the vacuum port to the dizzy doesn't get _any_ signal @ idle ? some carbys have two nipples , one pulles vacuum @ idle , the correct one for the dizzy always has ZERO vacuum @ idle . You can always disconnect it for testing but the power will be off a bit sans vacuum advance . To find those pesky intake vacuum leaks , I use a foo - foo can of aerosol starting fluid with the plastic snorkel in it , my '57 235 leaks from the underside of the inlet to head joints , burned the crap out of my knuckles finding that out
Nate, The carby insulator does look worn and apears to be starting to crack (chipped arounde the edge). Looks like a small amount of fuel residue around it as well. The truck still runs good and will be idling fine and then out of the blue at a stop sign the idle will just drop RPM's and the truck will just about cut off. Still runs fine though. Ordered a new insulator and base gasket. Checked the rusty manifold bolts and all seem tight. I have not checked for vacuum leaks around the manifold will do. What are the indications of a leak when checking with the starting fluid? Dont quite understand. The dizzy does nothing at idle but if If I advance the accellerator on the carby it starts to advance very quickly and if I rev the engine a little it advances all the way. Was going to by a vacuum guage and set the idle with that once I replace the insulator (Is this the best way to adjust the idle correctly). Also I have not checked the timing. Was going to buy a timing light and check that as well, but the truck runs so good have just not done it yet. All this stuff is new to me so I am learning. Is it easy to check and set the timing? Is a timing light the easiest way to do this? Thanks for your help.
O-Kay ; The truth comes out ~ timing not set means not ' tuned up ' Get a nice inductive timing light , it will have a plastic clip thing that slips around the # 1 spark plug wire then there's two battery clips you connect directly to the battery , not the coil or dizzy . I highly recommend the Sears Craftsman brand one , it's $50.00 and is a chrome steel case , mine has been in continual commercial service for 30 years..... cheap at ten times the price IMO . They make an upgrade version with an advance dial on the back , this is very helpful both in trouble shooting and tuning the mighty Stove Bolt 235 to maximum power and economy , makes the small block guys embarrased Setting the timing is fairly simple if fiddly , look above the starter for a window in the bell housing , it has a thin needle pointing down from about 10:00 , the timing mark proper is a small ball bearing pressed into a hole in the flywheel , what you want is to line up the ball and pointer @ 600 RPM's or so , if you can find a Dwell tachometer it'll help setting both the timing and idle adjustments _plus_ *perfect* adjustment of the points , even when they're 30 years old... I''m dying here , sorry . please look up my old tune up posts , if they're not clear ask me again and I'll write morw ehn the pain gives me a break , I have more messages to check right now .
Okay After reading many archived post on tune ups, timing set,dwell set, vacuum etc... (Thanks Nate). I decided to work on my truck a little while the wife was away. I purchased a timing light, tachometer-dwell meter-volt meter at auto zone. Had to search the net for the analog dwell meter. Auto zone has them ($24.99). They also have vacuum guages. As I mentioned earlier the truck was not idling smooth. Decided to run it up to the store to see how it was running and it was not running smooth at all. So I pulled it back into the drive to check a few things. Decided to recheck the points and plugs first. Hooked up my dwell meter and turned the truck over the point dwell was way off. I dont think I would have ever gotten it perfect with feeler guages, gap was way to wide. Set the dwell at 33 degrees. Rechecked/gapped spark plugs to .035 some of those were off as well. Reinstalled plugs. Decided to crank the truck and it was running much better but still sputtering and not real smooth. Sounded kinda like it did before I rebuilt the carb. Some white smoke out of exaust as well. Looked down into the carb while it was running and that nice smooth stream off gas I had before was now very erratic and dribbly. Also could see some trash down in the throat. Looked kinda like the brillow filling in the oil bath air cleaner had somehow gottin in there. Went ahead and removed the carb for cleaning and to replace the worn and cracked looking bakelite insulator spacer. Will also check timing and set idle with vacuum guage when carb is back on. I hope this will take care of my erratic idle. I will let you know. Since I have the carb off I have decided to go ahead and remove the intake and exhaust manifolds for easier access to two leaking freeze plugs (rusted) and replace them with brass ones. Should I put loctite on the new freeze plugs before intallation? Any advice on putting in/removing freeze plugs? Any advice on the manifold removal? I do have a new manifold gasket and will replace while the manifold is off. Will re-install and torque to factory specs. First time I have done this. I am also going to degrease and paint the manifolds and the engine and replace the pushrod cover gasket that is leaking oil. Anything else you would recommend doing while I have the manifolds off? Thanks
This 'N That O.K. , gotta set the timing dead nuts before you even *think* of carby fiddles as you cannot possibly adjust the carby unless the ignition system is bang on . Intake manifold , should (must) have three sheet metal alignment rings , one for each port , often gone missing and specific to 235 & 261 , cheap to but new if lost . Offer up the manifold and install all the bolts and special washers by finger then tightn just the two middle ones then the next one fore then the next one aft , it's critical to tightn the installation from center on out , evenly . NO bols/nut on the ends ! locating stud nubs ONLY ! . Freeze plugs , bash 'em in from the edge using a 3/8" long extensoin then grab the edge with BIG water plup pliers and fold a bit until they'll slide out . Probe deeply in the water jacket with a bent up coat hanger to loosen up the inevitable rust silt stuff , hose in the radiator helps flow it all out as you work at it , time consuming to do right but any job worth doing...... Yadda Yadda , old man drivel yes but who wheezes across Death Valley fully overloaded with three adults in the cab going 75 MPH in 125° heat ? No sealant needed on the new plugs , brass is very smart choice , just use a lipped driver or a big socket that fits them snugly.... Did I forget anything ? . Work carefully , truck parts you can get , new knuckles and eyeballs are on premanent backorder .
Okay got my intake and exhaust mainfolds off and guess what? Exhaust manifold has a hairline crack about four inches long. Can this be welded or should I replace the exhaust manifold? Where can I get a 235 Exhaust ?manifold? Thanks
Scrap it . Flea Bay etc. , if otherwise make sure it's returnable if the heat risor is damaged or it has broken off struds .
The heat riser is not damaged at all physically, it is locked up and rusty though (maybe this means its damaged dont know). The flap looks fine on the inside (black). The weight and spring are there. No boken studs. The only damage is a four inch crack on the underside of it. It apears to have been that way for a while. Will start searching for one soon. Any advice on where to look? Cost? Will any year 235 exhaust manifold work? Thanks again for your help Nate hope you get to feelin better soon!!
Sorry , I wasn't clear : Your NEXT 235/261 exhaust manifold needs to have a good flapper on it , no broken studs etc. Yes , any one will fit but be aware sopme years have a different angle on the outlet . $75.00 usually gets you a good one , ask in the classifieds section .
The old truck sure did run good for a while with that cracked manifold. Probably put close to five-hundred smooth running miles on it in the last three months. I wonder if I cracked it twenty five years ago when I used to drive it in high school with no worries? Probably would have been a little easier on it if Id known one day it would be mine. Will update once I get it back together. Thanks again for all the help!!
To help you in your search: 50 to 62 all 235 manifolds are the same the casting # 3835587 . always make sure the heat riser is moveable..
Thanks. Just curious if the heat riser does not move can it be repaired? How would one go about freeing it?
