87 Olds 307 questions

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Csilvy2000

Master Mechanic
Mar 14, 2012
251
87
28
Texarkana, AR
I'm guessing it jumped timing. Move the distributor around a little and see it'll fire off. First pull a plug and see if there is any fresh gas on it.
 

jetsetw31

G-Body Guru
Sep 9, 2010
678
67
28
Petersburg, VA
Did you fill the radiator while you were cranking the motor? If you didn't, I'd fill it with water for now and try and crank it. If it tries to start up in any way, then you have a blown gasket.
T
 

88hurstolds

Royal Smart Person
Jun 24, 2008
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Timing chain could have jumped too... common on 307s when the chain is stretched.
Make sure timing is set correctly.
When Im by myself I usually put a piece of tin foil in the #1 plug hole and crank till it pops out and then set the cap so that #1 is just passed to get a general start on timing.
 

81Regal

Royal Smart Person
Apr 5, 2009
1,557
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Terril Iowa
I did the tinfoil tip and when the foil was blown out the distance rotor was pointed to the #1 spot. The plug was damp so I put a bit more gas on it. Still no start. Put antifreeze in the radiator and didn't make a difference on the cranking.
 

jetsetw31

G-Body Guru
Sep 9, 2010
678
67
28
Petersburg, VA
Check the condition of the plugs again. look for antifreeze, excessive gas, or very dry.
If you see:
Antifreeze= blown gasket.
A lot of gas moister or strong gas smell = its flooded. Leave all the plugs out for a day, then try again without pumping gas into the carb.
A dry plug and no gas smell means No fuel to the plugs. But I think you have fuel, so its likely one of the first two.
T
 

81Regal

Royal Smart Person
Apr 5, 2009
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I went to the parts store this afternoon and got some new spark plugs. Pulled out the old ones, gapped and put the new ones in. The old plugs didn't really smell like gas except a couple of them, but they were damp, didn't smell like antifreeze either, guessing water. The previous owner did fill the gas tank full a short time before the radiator hose blew off.
Checked spark again with a new plug and it did still have a weak spark so Im thinking bad/weak coil or pickup coil.
 

81Regal

Royal Smart Person
Apr 5, 2009
1,557
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Terril Iowa
OK, swapped in a known good coil and module, the module in there was an aftermarket piece and did not look to be in the best shape. Getting better spark but still no start. Turned the distributor advanced and retarded, no difference in the cranking speed.
Noticed that the mixture solenoid in the carb didn't click when I turned on the key so I pulled the fuses, both were OK.
Radiator is still full of antifreeze so that is not seeping in the cylinders.
 

jetsetw31

G-Body Guru
Sep 9, 2010
678
67
28
Petersburg, VA
Ok check the plugs again and see what they are doing and look like. Right now the plugs are your best indication to what's happening. get a good idea would be to remove the 4 most outer plugs. 1,2,7, and 8. The condition of these plugs tells most of what going on. if they are still clean and unused, then keep changing ignition parts because you know the ignition is not properly firing. If the new plugs appear brownish the ignition is firing ok.
If the plugs smell of gas, then take all of them out and disconnect and cap the fuel line going to the pump from the tank. (Put a cup or container under the hose when you take it off, so to use it for starting later.) Disconnect the pink coil wire from the cap. Take 2 long screw drivers and prop open the carbs front and rear butterflies. Now crank the motor a few times. (It will spin real fast) This will free it of any fuel residue in the cylinders and intake.
ONLY if you smell strong of gas should you do this. After a few spins then put everything back EXCEPT the fuel line to the pump. leave that off and try to start the motor with no fuel. then pour a little fuel into the carb and see if it wants to start. Keep the fuel line off till you get a good start and run. Otherwise you will keep flooding it out while you figure what else could be wrong.
Keep us posted.
T
 

jae

Master Mechanic
Oct 11, 2006
460
2
16
It appears you checked everything and agree w/ jetsetw31, this will help in case there is a flooding issue. I could also help diagnose a weak pump or trashy fuel. A couple of things that haven't been asked / mentioned are:

1. Did you check the wires for resistance & to make sure they are routed in the correct order. Wires with excessive resistance can cause your weak spark issue.
2. What were the conditions he ran it under at that 285* temp, i.e. in garage idling, changing / flushing fluid, driving on highway, run time at that temp...
3. In terms of the hose blowing off
a. what made it blow off
b. where did the antifreeze go and did he clean up EVERYTHING
c. were any and ALL WIRES & GROUNDS cleaned and or replaced
4. Is cranking speed actually enough the fire engine
5. Has oil been checked for milk-shakishness - not just pulling dipstick but draining some out the pan / filter (also for petrol)
6. Is the carb fuel filter / spring installed correctly? If using a golden sintered-styled filter make sure it's in the correct direction (had an issue on a '66 Impala where I placed it in backwards, engine would start but after a few seconds or so it would sputter / die or shoot fuel out the carb if I tried to increase engine speed. Reversed it and no issue)
7. Have valve covers been pulled to ensure there are no valve train issues, like broken or loose rockers, pushrods
 

bill

Royal Smart Person
Jul 11, 2008
2,332
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38
southside va/lake gaston
Extreme pressure usually causes hoses to blow off....and blown head gaskets are the usual culprit for that. Or, somebody used plain water instead of antifreeze and there was a leak or low water level, which can cause steaming inside the engine/radiator/hoses, etc. Sounds to me like theres not enough compression to create ignition of the fuel/air mixture.... Just my two cents.
 
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