Hot Rods small block chevy won't start

I have a 305 chevy that won't start. I had the motor running a few weeks ago and found it had a flat cam so I tore it down and put a new cam in. while in it I replace the timing chain re-ringed it and did a basic overhaul. I got it put together and it won't start. I checked spark and it fires correctly on the correct compression stroke. the only think I have noticed is that I have a blub blub out the exhaust and it seams to have fuel getting in the intake but not to the spark plug. do you think this is a vaccum issue. I am no engine guru and really could use some expert help from some hambers

 

are you sure the timing is correct?

 

a 305 is just another gasoline engine and gasoline engines need three things to run.

Fuel/air mixture, ignition spark and compression. It does need them in the right amount and at the right time.

You did get the timing marks on the timing gears lined up right? And rotate the crank twice to make sure that you indeed had them lined up correctly? The books don't tell you to do that but it has saved my**** a couple of times when I was off a tooth with the cam.

Since you are getting burbles out the exhaust are the valves adjusted correctly? You may have them too tight and some are holding the valves open.

 

I think so I did it by the book put the two timing marks on the sprocket together then turned it over 180 degree on the top dead center mark then inserted the distributor matching numger one cylinder to that on the distributor. do you think it could be 180 out. I can put my finger over spark plug hole and it pushes off at the same time I get spark from the distributor.

 

You have a timing issue either at the cam or distributor. You might be 180 degrees off. Make sure that when the dist is pointing to #1 that the piston is on the compresssion stroke, not the exhaust stroke. Good luck. Keep us posted as to your solution.

 

I will turn the distributor 180 and see if it will start. The cam is a little larger too. I might also loosen the valves and see if that will help

 

Marks should be pointing at each other, then put in the distributor to #1, your are 180 degrees off...been there done that on a 396
On another 396 the owner ran the valves too tight, ran a compression test....40 lbs......maybe both problems as it should of backfired......

 

No firing at all? Usually, when the dist is 180 off, it'll try to fire, and you'll get an explosion.

I'm thinking tight valves maybe...especially with the "lub-lub" sound. Even with a vacuum issue, it'd run...not good, but it would run. The wet carb/intake, yet dry plugs...fuel not being*****ed into the cylinders...also leads me to believe that the valves might be adjusted too tight, and not providing a seal to cause vacuum during the intake stroke.

Or not.

By the way...read a thread recently about wiping cams, and how the metal fragments can clog oil galleys, and stay there even during a rebuild. Watch your oil pressure closely.

 

Scott, did you pull all of the oil galley plugs and the cam bearings and totally clean out all of the oil passages? I know this is not anything you want to hear, but it needs to be done if you haven't. If you look with the search function, we have discussed this before many times. I gave one HAMBer this*****ogy, take your old cam, your favorite grinder and some safety glasses. Now clean a spot on your shop floor and grind down a couple of cam lobes. Sweep up all of that metal, go out to your daily driver and open the oil fill, and ask yourself this question. Would you put all that metal into your engine? If you haven't done the above THOROUGH engine cleaning, maybe it's good that it wont start. I'm not trying to be a**** here, but those parts you bought with your hard earned money were probably not cheap, and they are just going to get destroyed, as well as maybe the crankshaft, maybe even the block. You can easily smoke a main bearing journal so bad the block is trash. Its just not worth it. I know its not what you want to hear, best of luck with your decision and your ride , TR.

 

sounds like timing to me...I've also heard of the valves not being adjusted corectly as well!

 

I'd say timing and valves.

 

If you are sure you have your timing marks lined up.....Bring #1 cylinder up to top dead center. install distributer so rotor is pointing to the number one spark plug wire on cap. even if valves were tight it would start. You have your ditributer in wrong.

 

look at the valves on #6 cyl.when there in "valve overlap" (exhaust closing,intake opening) the timing mark should be lined up!drop in the distributor or make #1 wire the ne that the rotor is pointing too.& start it up.This is a basic question so just re trace your steps & you'll be ok.
One thing though alot of 305 have the timing mark at the top of the damper(12 o'clock" & if you replace the timing cover there usually at about 2 o'clock.I don't know if you replaced the timing cover but its just another tidbit that might help.
JimV

 

Reading what you state dots at 12 oclock on crank 6 oclock on cam is correct.Without doing anything from here you have the engine at tdc.

TDC #1 on exhaust. not compression. At this time #6 is also at tdc on compression. If you don't turn the engine from here you must install the dizzy with rotor pointing at #6.Turning the engine one full turn from here 360 deg gets you tdc @1 compression.
You say you turned it over180 deg?? from the mark?? What mark?Are you talking crank rotation or cam rotation. You are all mixed up in your statement.We know the cam is in correct.Bump it over until you feel compression in #1 cyl Line up timing tab @tdc install dizzy pointing to # 1 and it will go.All this is****uming that you have the lifters adjusted correctly but you haven't discussed that here.

Tig

 

hey thanks everyone, I am going to try the 180 but think the valves may be the issue. I will go thru all the steps an hope it will start. thanks again for the help.