348 engine problems

[july2849]

59 Camino I had a 348 rebuilt with Edelbrock 409 heads, 409 dual quad intake, mild cam, pair of Edlebrock Carbs qnd a MDS HEI Dist and coil. Used Dougs Headers. Started right up @ 6 degrees BTDC. ran it for a few min to test motor sounded and ran good. Last attempts to start the Motor has become harder and harder to turn over. I did get it running last weekend but it died after about 5 min. Now it won't start at all. Had Starter tested-its OK. Got fuel, Got Spark timing checks out.
Pulled all plugs this evening and it would barley turn over, battery is new, all wires are new, ground wires new. Put a socket and cheater on pulley and could barley get it to move. Pushed Clutch in-tranny in neutral.
This motor has less than 20 min run time on a brand new build. What should next step be? Was thinking of squirting oil in plug holes to see if I could free up a bound ring, that fails pull the motor. Any Ideas would help.
PS: Block did have a welded up water jacket, which did start to leak a tiny bit after maybe 15 min run time. Was able to seal by grinding and JB Weld....so far.

 

[La Hot Rods]

Pull the valve covers and look for oil.
If this was a fresh rebuild and a new flat tappet cam, the engine should have been primed and checked that it had oil to all rocker arms. then start and run at 2200 RPM for 20 to 25 minutes and kept at operating temp.

 

[july2849]

I'll check tomorrow-but I did pull Tappet Covers and re-torqued and sealed head bolts-thinking I had a bolt not sealed, remember seeing some oil but I'll check again-I'm old and forget.

 

[La Hot Rods]

What does the oil look like?

 

[Phil Reed]

Piston to cylinder wall clearance too tight??

 

[1964SuperStocker]

No mention of it slowing down as it starts. Does that sound any different like its slowing or struggling when you turn it over? I say that because you might have welded your mains to the crank. What is your water temp and oil preasure specifically when it was running? Bad coil, Bad plug wires, bad cap, bad rotter. Clogged fuel line, I love that one. Had a really really nice $80K prostreet drag car we paid another shop to figure out why it was acting so funny with its high end fuel injection system. I bet it was a $10 fuel filter and no one believed me until the $300 bill came back and said "trouble shoot, fuel filter".. LOL!
What kind of die? Is it a sputter at first, does it cough or back-fire, maybe you hear a squeak or a rubbing noise? If you haven't spun a main before it can fool you because everything can act fine, then it just slows and stops spinning without notice basically. Once it cools it will run again until it gets warmed up and hot where it stops again. This cycle will get worse with each try until your breaker bar won't turn it over. Could be the Rod bearings too. As they say, if its not a cheap fix then its an expensive one. I'd be tempeted to pull the oil pan and inspect it from below. I have a $15 inspection camera I can attach to my phone for just that purpose.

 

[1964SuperStocker]

Piston to cylinder wall clearance too tight??

Also wondering what kind of pressure your cylinders are giving you. Yank your plugs and check each one and report back. Also tell us if it cranks hard with the plugs out. Should spin pretty freely with them all out.

 

[63impalass409]

I beleve he said it would hardly move with plugs out so I'm with the above comment from 1964superstocker on the mains welding themselves. .

 

[1964SuperStocker]

I beleve he said it would hardly move with plugs out so I'm with the above comment from 1964superstocker on the mains welding themselves. .

Yes, dah. To many things going on at once, he did mention pulling the plugs.
I had a crank do that to me once but it was due to an oil pump failure on a well worn engine. Dummy light didn't kick on. Have had gauges for everything ever since.

 

[july2849]

yes I did pull the plugs and the Motor will barley turn. Oil is fresh-(added some Zinc at first) and looks that way.
I have a pressure gage on the fuel line so I know its getting fuel and the carbs are squirting their fair share-plugs are wet w/ gas.
I did notice after I charge the batt over night the motor and the motor sits-it spins more freely for a very short bit.
When it dies from running it simply slows down no backfire. For sure is slows down as I try to start it and struggles to start. It appears that its degrading itself the more I try to start it. Will pull tappet covers and look for oil.

 

[wristpin]

Id call the engine builder and have him get his ass over there. Something internally is welding itself together. Dont do anything except take pictures and document everything thats happened in case he doesnt stand behind his build.

 

[Don Jacks]

Pull it back out,pull the oil pan,and start inspecting every thing down there.Bearing clearances,bearing orentation[rod in backwards?],main clearances,ect.look at cylinder walls for scrapes,scratches that would indicate things like cylinder to piston,or incorrect ring gaps as the cause.Even things like too rough a hone job for the type of ring being used can cause some of this.

 

[Iowa 409 Guy]

I'd cut the filter open and you'll more than likely know why Don is recommending to pull the motor. Damn, that's too bad. Welcome to the forum.

 

[Fathead Racing]

Some of us here that build our own engines know this disappointment. I've been there. Had less than 10 hrs on my first 348 build and had a rod knock. Oil pump problem that I should have caught but inexperienced I let it pass. Don't let it get you down. I used to kick shit until I hurt my foot.

 

[Jim Sullivan]

And now you just shoot it Ray?

 

[Don Jacks]

Ray's learned in his advanced years that shooting something is less painful to him than kicking it.

 

[1964SuperStocker]

Pull it back out,pull the oil pan,and start inspecting every thing down there.Bearing clearances,bearing orentation[rod in backwards?],main clearances,ect.look at cylinder walls for scrapes,scratches that would indicate things like cylinder to piston,or incorrect ring gaps as the cause.Even things like too rough a hone job for the type of ring being used can cause some of this.

Rod in backwards...forgot about that too.

 

[wristpin]

Rod in backwards...forgot about that too.

Wouldn't it be really obvious that the crank end of the rod was wobbly on the wristpin and the piston end was tight on the crank? I've been drunk before....

 

[1964SuperStocker]

Wouldn't it be really obvious that the crank end of the rod was wobbly on the wristpin and the piston end was tight on the crank? I've been drunk before....

There you go using logic again.

 

[july2849]

yes its very depressing-but its Feb with 3' snow in Nebraska what else is there to do. The only other possibility a friend brought up was I used too long bolts on the flex plate - but I'll pull the motor and take it to the builder. But of course the original builder just retired and moved out state and I get the new guy. Trouble is not many builders here and I am tossing around taking it to another shop out of townt-BUT I did Hedge my bet and have a spare 348 out of a running car sitting on a stand, I only need the bottom end-all the upper parts are 409 heads-intake. And I wanted a mild easy running motor to tool around in.
One question is did the 348's have a tapered bore?