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#28076 11/10/2001 6:35 PM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | I have a '53 235 in my '48 3/4T, still with the 4:57 rear-end. I'm pretty sure the engine is a full-pressure one from a car with an automatic (engine # LAQ 83376). The engine runs smooth as a top for my usual 3-5 mile trips around town every day. But when I take it out of town 10-15 miles at 40 MPH and really warm it up to the core, the idle speed increases and it seems to miss. It's kind of a fast slappity, bangity. When it cools down it goes back to normal. I haven't checked the timing when it enters this mode, but does it seem like a distributor problem?
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
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#28077 11/11/2001 3:20 AM | Joined: Jan 1970 Posts: 365 Shop Shark | | Shop Shark Joined: Jan 1970 Posts: 365 | You may want to check your heat riser valve to make sure it is not stuck. If the counter weight moves and the spring is there, you should be all right. Sounds to me like the heat riser is stuck in the shut (cold) position. | | |
#28078 11/12/2001 8:15 AM | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | Check to make sure your valves aren't adjusted too tight, in addition to the manifold heat valve.
Paint & Body Shop moderator
A lone amateur built the Ark. A large group of professionals built the Titanic. | | |
#28079 11/12/2001 11:56 AM | | Anonymous Unregistered | | Anonymous Unregistered | Also check that the intake is not sucking air after warm up. Common on a 235.spray some carb cleaner around the intake to head and around the carb base. CAUTION this can produce fire so dont use a whole can. Maybe retorque the intake(most times if its leaking its to late) I have also seen about 3 -4 warped 235 intakes that i had to cut.Check the carb gasket also and make sure the carb is tight. | | |
#28080 11/12/2001 6:29 PM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | I freed up the heat riser valve a bit. Should you be able to turn it with your fingers?
I'll use a little bit of carb cleaner around the intake manifold ports when cold and then hot. I will wait for one squirt to evaporate before hitting the next intake port.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
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#28081 11/13/2001 8:50 PM | Joined: Jan 2001 Posts: 230 Shop Shark | | Shop Shark Joined: Jan 2001 Posts: 230 | Wally - do the tune up thing , ALL of it , then follow the directions everyone recommended . I had and old Chevy 6 - banger that had a collapsed piston skirt - it slapped and banged terribly when fully warmed up and burned quite a bit of oil too - ran like that for years and years , keeping it properly tuned , of course .
-Nate
There is no problem so difficult it cannot be overcome by generous application of brute force & ignorance
| | | | | Joined: Mar 2011 Posts: 17 New Guy | | New Guy Joined: Mar 2011 Posts: 17 | Also, that dooflinkie spacer that you should have betwixt the "rot pot" and the manifold to keep the gas from overheating(vaporlock and all that)should be secure and tight, some guys use gaskets on both sides, as I have, the manual says its not needed, and we can all fight about that until the next war, but I noticed a HUGE difference in fuel milage after sealing it with bathtub sealer, some paint to make it pretty, two hail Marys and some salt thrown over my back for good measure.As far as piston slap goes, after a minute or 2, it should be gone. I have a 409 that has horrendous slap when cold,as these motors are known for and as scary as it sounds, theres no problems,Chevy dealt with this issue late '62, but my '65 "nine" still sounds like a box of rocks when cold. | | | | | Joined: Jun 2010 Posts: 384 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 384 | Hmm.. I had a friend who told med that the damned heat riser valve was not needed if you only drive it in the summer time.
So he removed it when he fixed a big crack in the manifold.
And of course I should have sealed off the intake from the exhaust with a thin plate or something. Now I guess I will end up with the same thing when it gets hot. =(
My Chevy Viking 1959Ulf Hedlund. Eskilstuna. Sweden [email protected]Also: Ford Galaxie 4 dr 1959 Ford Custom 4 dr 1964 Ford Mustang GT 2005
| | | | | Joined: Oct 2006 Posts: 1,847 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 1,847 | ok on the heat riser, which is open up or down? | | | | | Joined: Feb 2000 Posts: 5,213 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,213 | The weight pulls it closed. spring opens it so heat goes up.
Joe | | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | Wally
It sounds like the engine was tuned before it got to full operating temperature. When the engine gets fully warmed, many items expand and when this happens, things run differently.
Perform all the tune-up tasks, just get the engine good and warm first.
SWEET Sergeant At Arms: Old Dominion Stovebolt Society BUNS?!?!?!Where we're going, we don't need no buns.....1950 GMC 450 1951 Chevy 1/2-TonThe GreenMachineIn the Stovebolt Gallery | | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 |
Last edited by Denny Graham; 06/28/2011 1:35 PM.
Denny G
Sandwich, IL
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
Do you recent posters realize that this is a very old post "revived" by a jerk, ELKAYE, who has done this with several other posts over the past few days? He must be having a good time wasting everyone's time.
He should be warned and/or kicked off the discussion board.
| | | | | Joined: Feb 2004 Posts: 29,792 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,792 | Forget the warning- - - -find a tall tree and a short rope!
:mad: :mad: :mad:
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | Be nice, he is just a wayward newbie
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
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