My 83 F-150 302V8 was running ok. I stopped to run
in a store and came out fired up and went about 30-50Ft and it cut off. When the engine spins it has a different sound. Engine will turn over,but will not start, checked rotor button and it turns, and I have spark.Engine has ~135k on it. How can I tell if the timing chain is off or jumped? Also how difficult is it to change? I know that's a relative question. Can timing chain gears/sprockets be changed w/o pulling motor? How do I find TDC w/o pulling the head off?Sorry for the numerous questions, but I could ask a hundred more......

Thanks,
Gary

 

Gary:
Pull off a valve cover and turn over engine if you see the rocker arms moving up and down the chain is not off.If they dont move then your assumption is right.I would imagine if the chain skiped a tooth it would be backfiring. If this is your first time changing a chain get a chilton manual on your truck their around $15 or so.There is no need to pull the moter for the job.The easiest way to find TDC is to take out the spark plug on #1 cylinder and waud up a piece of paper and shove in the whole (just into the threads not in the cylinder)turn moter over when the paper blows out your at TDC on compression stroke.You can also put your finger over the whole and have someone turn the moter over by hand when you feel the air pushing through your finger your there. Look down at the timing mark on the harmonic balancer and line it up on the 0.
Good luck and hope I was of help.

 

Jay I'll try it out and let you know what I find.
I saw a Haynes manual in Autozone are they pretty good?

 

First I think a Chiltons manual would be better than a Haynes. I have a Haynes for 73-79 F series and Broncos and with all the different engines and chassis and trannys ect. It is kind of generalized. I have disassembled a 302 that I had 1980 block 1985 heads. If you need to change the timing chain, you will need a gasket kit and keep track of which bolts went with which holes. The timing chain cover is integrated with the water pump. It has passages that the coolant travels through to get between the block and the water pump. Some of the water pump bolts go through the timing cover. I didn't have trouble removing the bolts but I had a friend with a 83 Tbird who broke several bolts while trying to remove. I believe that the timing pointer hides a mystery timing cover bolt. You will probably have to rent some tools like a harmonic balancer pulling tool and maybe a timing gear pulling tool. I got by with just needing a harmonic balance puller and using 2 long screwdrivers to pry off the cam gear. I replaced my first timing chain recently on a 390 and then did it over again after replacing the cam. I didn't seem to have any problems. You will need a torque wrench. There will be several gasket seals that will have to be redone when you reassemble the front of your motor so you will need the gaskets, and some adhesives. I used grey RTV for timing cover and oil pan and some sticky greenish crap that was recommended to me at the auto parts store for water pump and fuel pump gaskets. I haven't started rebuilding my 302 yet (I not sure I will I may use a 351W instead or transfer my 390) I would keep real careful track of the timing cover water pump bolts because they come in various lengths. Also I have busted a couple of timing cover bolts by over torquing them. I have a busted one in my 390 block in a waterjacket. I just plugged the hole with RTV and hoped it didn't leak. It didn't. Regarding finding TDC, remove the valve cover off the passenger side. Cylinder #1 is the front most cylinder. Compare the timing mark on your balancer with the valves. Every other time your mark comes around you are at TDC. The valves on #1 should be shut. Also pop the distributor cap. Figure out which contact is #1. trace the wire, it should be near 2 oclock if 12 were pointing back towards the cab. See where the rotor is pointing. If your timing chain broke, or spipped a whole bunch, your distributor is driven off the cam and it will be wrong. However if it is not radically off it helps to figure if you are on TDC or 180 off.

 

Anouther thing that you can check is the distibuter drive gear pin. I have seen several of these things break. Sometimes the rotor still appears to spin. You can take the dist. cap off and try and turn the rotor back and forth with you hands. If it goes in circles the pin (or whole shaft) has broken. If this has happened be sure and install the dist. with out the gear on it and see if it spins. If it does not your oil pump has locked up. If it does spin install gear and you will be set. Good luck.

 

I appreciate all the help guys and will use it whenever this rain stops. I'll let you know what I find out.
Gary

 

THE LAST THING YOU SAID WAS THE KEY TO MY REPLY. IF IT WAS RAING OR HAD BEEN RAINING ON THE DAY YOUR TRUCK DIED, YOU SHOULD FIRST CHECK ALL ELECTRICAL COMPONETS UNDER THE HOOD. SUCH AS: SOLENOID ON THE FENDERWELL, IGNITION MODULE ON OPPOSITTE SIDE FENDERWELL, ALL CONNECTIONS INTO THESE COMPONETS, AND MAYBE EVEN THE DIST. CAP ITSELF FOR ANY CRACKS. ANYTHING ELSE ELECTICAL SUCH AS FUSES, RELAYS, FUSIBLE LINK SHOULD ALSO BE CHECKED. THE REASON FOR THIS IS IF THE MOTOR AND ALL OF THE COMPONETS WERE HOT, WHEN THEY WERE HIT WITH WATER THEY COOLED AND CRACKED OR BROKE. JUST A THOUGHT ANYWAY, ITS EASIER THAN PULLING THE FRONT OF THE MOTOR APART. BEST OF LUCK!!

 

Gary D.,

I agree with sean rose concerning the rain issue. The first thing I thought about was a cracked distributor cap. I would also advise to check all of your electrical options under the hood before anything else.

Steve

 

I finally got to check things out, when I got to TDC on the compression stroke rotor was nowhere near #1, so I started tearing in and sure enough the old nylon gear was really worn and the chain had slipped. Should finish replacing it tomorrow, hope it didn't damage anything else, I miss ol red. An 86 Accord is not a he-man vehicle.....
Thanks for your help everybody.

Gary