HELP -can't get it to run

[Bungy]

This might be a little off topic from the 58-65 era, but with all the brain power on this site maybe someone can help. My brother recieved a 305 from a 80 half ton for free. After we found out it turned over we tried getting it to run (if only for a minute) Why? cause that's what gearheads do. Its just sitting on an engine cradle with the starter hooked up and a hot wire to the HEI. Battery pos to starter and neg to intake manifold. The fuel pump works, the carb works (squirts gas in when throttle is depressed) We have spark on 4 of the plugs we checked. It seems to crank slow so we tried three different starters (one a high torque) but the same results. We even loosened the rods and the mains, but still cranks slow. With the plugs removed it turns faster. The firing order was checked and rechecked about ten times. We tried a different HEI cap and coil. We can barely hear a pop from maybe one cylinder.
Is it possible that the compression is too low for ignition? We checked all the cylinders and got 75-75-50-40 and the other side 75-0-30-50 psi
Anyone have any ideas or tips to get this POS to run? Are we missing anything? I have to get it to run as I've spent too much time on it to give up. :

 

[No409]

I just checked my Mitchell, spec is 150 cranking compression on a 83 305( as far back as my computer goes), with a minimum of 100 psi

Hope this is of some help

 

[oldskydog]

I'm sure you have already checked the obvious but timing chain/gear comes to mind. Another thing that I remember from back then is that some of the 305s had a reputation for cams going flat and I had one of them. It just quit making power but it would start.

 

[models916]

NO compression

sounds like the valves are shot or stuck slightly open. That 0 is a giveaway. If you have 0 on compression, how much do you think you have on intake?

 

[Bungy]

We have taken off both valve covers and all valves are moving. Even so I would think we could get at least ONE cylinder to fire or pop. That's the most frustarting and baffeling thing about this pile. The distributor rotor is turning. Once again if the timing chain had jumped we should still get it to pop someplace. We have good spark when the plugs are removed but its as if they quit firing once they are screwed back in? We removed the plugs and sprayed some WD-40 right in the cylinders and put the plugs back in and still nothing. Then the battery went dead so that's where we're at now. It just doesn't make any sense

 

[dq409]

Any engine that sits for a long time can loose compression due to dry rings among other things.
I always squirt some oil or trans fluid in the spark plug holes BEFORE trying to start it. WD 40 is too light of an oil.

if it is really bad leave the oil in there over night then turn it over the next day with the plug out.
install plugs and give it a try.

 

[bluescreamer]

get it to run

Bungy
I would think if a motor sat for a long time , the oil in the lifters would have bleed away. Thereby causing wrong cam timing. You have to spin motor
quicker to build oil pressure. Back off valve adjustment and try again.
Just a thought.
Allen

 

[dq409]

You can check the valves and rings.
Remove the valve covers and one cylinder at a time bring the piston to top dead with both valves closed.
Then with compressed air, (i made a screw in adaptor from a old spark plug) add air to that cylinder.
Listen for air leaking into the crank case through any hole going there. This will show leakage around the rings. Some air is OK,, alot is not

Listen for air coming out the intake and exhaust ports. This will show leakage from the valves. You should hear no air if the valves are good.

Squirt some oil into that "0" hole, rotate the engine by hand a few revolutions then retake a compression test in that hole and see if the value comes up.

Good luck,, dq

 

[Bungy]

These are all really good sugestions. I don't know how long that engine sat before we got our mits on it. I did prime it with a drill before we started anything and the primer has a bushing for lifters. When doing this I saw some oil coming out the tops of the pushrods.
We also poured some oil into the cylinders and it did spin faster but we never rechecked the compression. I guess my main question is could the low compression or lack there of be the reason there is no ignition? No matter how far off the timing is, I would think it would at least pop out the exhaust, the carb or someplace.

 

[dq409]

You stated you lossened the mains and rods."We even loosened the rods and the mains, but still cranks slow." Try and start it loose? Did you retorq them?

You said it turns over slow. Does it still do this? Is your battery good and fully charged?
What cables are you using to hook to the starter and ground?
These should be standard battery cables or a very good set of jumper cables.

"I guess my main question is could the low compression or lack there of be the reason there is no ignition?"
Yes! But you should be able to get a pop or something.


Do the plugs get wet when you try and start it? Gas fouled plugs won`t work.

Do the oil in the cylinders again with each piston at the bottom of the stroke, rotate by hand between adding oil to each cylinder.
Then with the plugs out rotate with the starter.
take another compression test.

If the numbers go up try and start it. Use some starting fluid .
If not ,,,, boat anchor it,,,, dq

 

[Bungy]

update on the 305 pile

I wasn't able to work on it this past weekend because of back to the fifties and it's at my brothers place 30 miles away.
Well it looks like dq might be the closest. fouled plugs?
I was thinking this: The engine sat for a long time and all of the gas evaporated out and the floats in the carb dropped. Then they froze or stuck in the down position so the fuel pump was pumping gas right into the engine. Possible problem #1
Second problem. My brother noticed the flexplate was bent (did I mention when we removed it from the tranny there was only one tight bolt into the torque converter, one half way out and the other missing?) He called and said he took it off and put it on the ground and stomped it flat (or close to flat) He also shimmed the starter to move it farther from the flexplate. This worked as it now spins a whole lot faster.
The fuel pump was disconnected and starting fluid sprayed into the carb, Eureka!
He said he got it to pop on a few cylinders and then the battery went dead.
It looks like these were the main problems, fouled plugs and slow cranking.
One more thing. we never did torque the rods and mains, just snugged em up.
So, I predict it will run this weekend (and maybe toss a rod)