85 305 died while running wont start
ok guys i have a 85 c10 305 also have a problem as well.... i was driving
down the highway about 70 mph and it just shuts down. tried to start just
cranked and back fired a couple times. i've since checked the distributor
everything is fine cap and rotor so everything is fine there. never pulled
distributor out so as to not loose time. but took timing cover off and noticed
that it had jumped time. replace the timing set and set everything correctly,
put everything back together. also checked spark yes has good spark and
fuel still no start acts like it wants to sometimes but also has backfired a few
times..... any ideas?
Did you rotate the engine over 2 revolutions after changing the timing chain to see if the timing marks line back up? This almost sounds like the firing order is off also.
Since it jumped time I bet the distributor is out of time. I would make sure when on the compression stoke and #1 is TDC check the rotor to see that it is pointing at the #1 distributor cap tower.
Check the compression if Rowefast's suggestions don't get you going. On some engines the timing chain marks are 12 o'clock crankshaft sprocket and 6 o'clock camshaft sprocket. But others can be both sprockets at 12 o'clock. Your distributor may need to be reset as Rowefast said too. Over time as the timing chain wears this also changes your ignition timing. People will often adjust the ignition timing as part of a tune up not realizing that the timing chain is wearing. HTH. -Jim
Say Js08016, when the crankshaft is at 12 o'clock and the camshaft is at 12 o'clock, 1 revolution of the crankshaft makes the timing marks at 12 o'clock on the crank, and at 6 o'clock on the cam gear, thus the lining up of the gears are easiest to do when the gears are dot to dot, 6 & 12 o'clock. It takes 2 revolutions of the crankshaft gear to spin the camshaft gear 1 revolution so your timing marks line back up dot to dot.
Also, when the timing gear marks are lined up, crank gear at 12 and the cam gear at 6 o'clock, then you are on the compression stroke for the #1 piston. Dot to Dot. Then you plant your dizzy in so the rotor is pointing at #1 tower (on a '85 engine) on the distributor cap. 1996 V8 on up Vortec engines are the same, but the distributor cap inside lead for #1 is at 7 o'clock because of the design of the cap. All the same for the V6 Vortec engines.
Hi Rowefast. You're 100% correct. But for some reason on some older GMs they want you to have the timing marks at 12 o'clock on both the crankshaft and camshaft sprockets when setting the valve timing. Cadillac and Pontiac in particular. This actually puts the #6 cylinder at the top dead center (TDC) position of the compression stroke and #1 at TDC of the exhaust stroke. I realize that we're dealing with a Chevy here but just wanted to throw that out there just in case. This drove me nuts one time on a '68 Cadillac 472! HTH. -Jim
Yea, I remember you telling me about that. Still I see what you say on that, but you have more chance for error doing it this way. I would think you need to know where #1 is on a motor you are working on, and rotate the engine so the timing marks are like this so it is on the compression stroke on TDC to plant the dizzy. When putting my engine together with my extremely smart buddy, he did my timing marks this way. It took me a year to figure out he was a tooth off. I had to tare it apart and reset it. I was not too happy. But knowledge is the key, in this case there is more than one way to skin a cat.
I agree, Rowefast. I hope the original poster let's us know what they find out. -Jim
Well. Here we go... I've reset the distributor nothing.... checked the valves and rods to make sure nothing was bent either.... still nothing. Has fire has fuel timing set Still will not start. Backfired a couple times and still nothing
Did you do a compression test? -Jim
No But it died running down the road. Hell I don't know what to do with it
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