Chevy 350 v8 issues

[Gunner3456]

It sounds like our e-10/e-15 gas loosened up some fuel system varnish and some of it is lodged in the needle/seat assembly(ies) on your Holley.

This is a good thought because it's easy, and checking the float level is a good idea. I don't, however, see how plugged jets could cause both backfiring (yes I know a lean condition can cause backfiring) and black smoke which indicates a lot of unburned fuel. ?? I still agree it should be checked as routine maintenance.

And don't let anyone talk you into scrapping that Holley for the far more complex and inferior edlebrock carb!

Agreed!

 

[Weebs]

Well good news and bad news...

First the good... (i'll make a 2nd post with the bad)

As requested here are photos of the project.

Start:
As you can see it has very splotchy paint. The previous owner rattle canned over the top of flaking paint and it looked like crap.


Finish: (sort of)
As you can see it's quite a bit different. There's still a lot to do, but at least it's good looking now.


If anyone is interested in reading/seeing my build progress I did blog about it. You can look here: Weebs' blog

 

[Weebs]

And now for the unfortunate bad news...

You all were very helpful yesterday in giving me suggestions as to what to look for. Unfortunately I think some of you were right...

I got home last night and hooked up a ignition circuit tester and it seemed that all of my plug wires were working fine.

So I started doing a compression test.

plug #2 tested at 90
Plug #4 tested at 90
Plug #6 tested at 90
Plug #8 tested at 150 but I think this was a false reading because the line filled with gas.
Plug #1 tested at 95 but was filled with gas
Plug #3 eventually got up to 90 but took a lot of cranking... also filled with gas
Plug #5 was skipped because of the 350 conversion this plug is a PITA to get to.
Plug #7 eventually got up to 90 but took longer than #3... also filled with gas.

With the way 2,4,6 tested I would assume that is the "norm" and all my others are acting up.

Every plug that I pulled was very wet and possibly fouled. They were cleaned and brushed and regapped before re-install.

I truly appreciate all of the help guys. But at this point I'm thinking I might be in over my head and needing to call in a family friend who does mobile auto repairs.

 

[deadeye]

I have not had good success with newer plugs cleaning them and reusing as once they foul they are not good/up to par, they're cheap just replace em. A cylinder that has oil or fuel in it will produce a higher compression and if they have had fuel in them for long I would change the oil once it is running properly.

Nice looking rig hope your friend gets you going cheap and easily.

 

[Gunner3456]

+1 I have not had any luck with cleaning and re-gapping newer plugs. Be sure to spin that engine to expel excess gas before replacing plugs. Then check the float level, replace the float needle, and check the primary and secondary jets before attempting a restart.

There are several things which cause me to wonder if that engine is worn out. Low compression might indicate a lot of miles. On a small block Chev, the rings often last longer than the cam, lifters and cam timing gear and chain so if the rings are worn...

The heads are notorious for burning valves, often caused by worn valve guides. Worn valve guides can allow the engine to suck oil down the guides and burn it.

Does the smoke coming from the exhaust have a bluish color to it? If so, it's probably burning oil in excessive amounts. If it's black, it's probably unburned fuel, which might be cured by carb work unless the engine has problems where certain cylinders aren't firing due to burned valves, bad cam and lifters, or even broken or otherwise bad rings.

Please read the instructions with your compression tester. You aren't supposed to spin the engine until you get max pressure. Usually, you just turn it over a couple of times.

 

[moose]

And we need pictures...some of us are TLC junkies!

I have a '76 Fj-40 with a small block chevy.

 

[Gunner3456]

I forgot to mention. Especially when plugs are hard to reach, it's very easy to crack them, and the cracks can be very hard to detect but they won't fire.

I hate to say this, but you have to pull that last plug even if it means removing the distributor so you can jack the engine up after removing the bolts from the motor mounts.

If you have to pull the distributor, use a felt tipped pen to mark the position of the rotor to the housing exactly, and then mark the position of the distributor housing to the intake manifold. I do that at the vacuum advance. Now, DON'T turn the engine over at all, and you can drop the distributor right back where it was.

 

[Weebs]

RESURRECTION!

After a couple weeks it's back up and running. About 2 hours ago I got home from my test run.

3 issues were found, 2 were problems.

1st: after it died I replaced the cap and coil. In doing so I didn't put the ground in. It ran (terrible) after doing this but after it wasn't right.

2nd: Timing was overly retarded. THat is now fixed.

3rd: this is the big one... All you people who guessed carb... pat yourself on the back.

My holley needing a complete overhaul. Instead of inventing the time and money to do this I hopped on craigslist and bought a Carter AFB carb. Put it on, adjusted the screws. BLAMO. Back to working.


THank you all for the help!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Weebs]

ohh more info on my compression test...

My harbor freight gage... WORTHLESS.

All cylinders tested above 140.

 

[rusobr2]

just a note for you, and the rest of "shade tree" mechs. out there..... shucks, or O'rileys has all the little testers out there that you can rent for a couple of bucks each ! our store here in "prineville" has all the "pullers" & "gauges" to boot, and they keep em ready to go.......
i was going to say, that with your orgl. comp. test (you need a motor) i'm glad you come up with a better comp. test !!
also for another note... i'm not sure if your new carb. is a center pivot float, and being you put it on a "JEEP" type chassis, i'm going to figure you mite do a little four wheeling down the road . if you experience some flooding when you get the jeep over to side or heavy corners, check your float..... also a stock 350 can only handle about a 650 carb., and idle good, anymore, and you can experience rough running at slow speeds or corners....
just my thoughts....

long time chevy runner......steven

 

[Redcap]

RESURRECTION!

After a couple weeks it's back up and running. About 2 hours ago I got home from my test run.

3 issues were found, 2 were problems.

1st: after it died I replaced the cap and coil. In doing so I didn't put the ground in. It ran (terrible) after doing this but after it wasn't right.

2nd: Timing was overly retarded. THat is now fixed.

3rd: this is the big one... All you people who guessed carb... pat yourself on the back.

My holley needing a complete overhaul. Instead of inventing the time and money to do this I hopped on craigslist and bought a Carter AFB carb. Put it on, adjusted the screws. BLAMO. Back to working.


THank you all for the help!!!!!!!!!!!!!!!!!!!!!!!!!!

I can't stand Holleys. First thing I do when I buy a rig with one is throw it in a pile of scrap in the front corner of my barn and throw an AFB (or, if the motor will support it, a TQ) onto it.