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| | | | Joined: Jun 2009 Posts: 235 'Bolter | | 'Bolter Joined: Jun 2009 Posts: 235 | Sooooooooo, apparently I'm an idiot. I asked a question about a timing bb on the flywheel being 180 degrees off, as i thought my cousin was saying he found tdc near an arrow 180 degrees from the bb. I WAS COMPLETELY WRONG
On the flywheel there are these markings:
UIC. A bb with a number 5. And about 5 teeth in front of that is a triangle i was calling an arrow. He said he found tdc closer to that triangle. I have no idea where i got it being 180 degrees off.
So, can anyone explain that? Its a flywheel from a 53 truck on a 56 to 57 235 from a car. Could that affect it?
Sorry, you all must think im crazy for even thinking my original question was possible.
'53 Chevy 3604 Five Window Cab ('56 235)
| | | | | Joined: Feb 2004 Posts: 29,774 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,774 | Depending on the year of manufacture, there are several flywheel marks. All of them are close to top dead center, but not necessarily exact. The only way to know for sure which is which is to use a degree wheel mounted to the crankshaft while the engine is being assembled, and physically check each one. There is a way to establish true TDC with the cylinder head on the engine, but I'm not going to try to explain it online. Call me!
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 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | I haven't use the marks for timing in years. I time to the fastest and smoothest idle. Works for me.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Start at BB on no. 1 compression stroke. See where no. 1 on dizzy is. Be sure plug wires are right per firing order. Start and tune to ear and performance as Martin says. You can also use a vacuum gauge. If you are like most you don't have a degree wheel or want to dig do deep just to time a motor. Paint the ball white.
Don't look in the wrong timing hole. Should be on pass side. Could be a hole on each side. Use the hole that has a pointer in it to align to the ball. There can be a plug in the hole, covered with grease and you will not see it.
I believe the way you read the flywheel markings is as follows. Time with the ball right on the pointer. The 5 next to ball indicates the ball is at 5 deg BTDC.
The UIC is actually "Upper Center" with a hash mark in between U and C. This is TDC. Which is a reference to when pistion is topped out exactly. The triangle is a factory test spec mark.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I use Tony's method, then slightly advance it 'til it just starts to ping under load, then retard slightly. At higher altitudes(5,000' plus here) one can advance and lean out slightly over sea level settings. Lower octane fuel works fine here.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | Tiny, in two posts you went from being you to being me to being some guy named Tony. That’s got to be some kind of record!
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Holy cow!! I was reading an old timing post. Had both post up. Martin said he tunes it by how it idles and runs. Then I posted an agreement on this post. My multi-tasking days are over. Tiny had already said the same here as Martin did 4 years ago. What a goof up by me. I apologize to whoever I'm talking to. I don't know anymore. The caretaker already went to bingo.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 |
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Tiny, in two posts you went from being you to being me to being some guy named Tony. That’s got to be some kind of record! Martin, I've been called much worse. 
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Dec 2015 Posts: 52 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2015 Posts: 52 | set your timing at bb, then get a timing light with an advance built in, and proceed to 10 degrees advanced with vacuum disconnected . i found 235/261 run best | | | | | Joined: Dec 2015 Posts: 52 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2015 Posts: 52 | set your timing at bb, then get a timing light with an advance built in, and proceed to 10 degrees advanced with vacuum disconnected . i found 235/261 run best | | |
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