Hey everyone, so I just got done rebuilding and installing the 400 engine in my 79 F250. Before pulling the engine the truck ran great at idle but not so great when driving (I think because of the cheap hei system I installed) but it had basically zero lbs of oil pressure. It already had an edelbrock intake and Holley 600cfm carb on it before the rebuild. I decided to ditch the hei system and go back to the original duraspark system with a new ICM.

When I went to start it for the first time yesterday the engine didn’t even pretend to start. Absolutely nothing. I checked to make sure the 1 cylinder was at TDC on the compression stroke by putting my finger over the spark plug hole and cranking till it got blown off. I then installed the dizzy so the rotor was pointing at the 1 post and I seem to be getting a healthy spark. My problem seems to be I’m not getting fuel to the spark plugs. I’m getting plenty of fuel to the carb and I have an in-line pressure regulator set to 5.5lbs. I filled the float bowl with fuel and I even poured a little directly down the carb but the spark plugs are still completely dry. They don’t even have a faint gas smell to them. Any ideas what could be causing this because I’m at a complete loss. I really appreciate any advice y’all have.

 

If you any gas and any type of spark no matter how it's set something will happen.

Check to see if you have spark, if you do pour a little gas down the carb and try it again. if you crank until you fill the cab it's too long it's taking your cam lube off, always prime a fresh rebuild with gas so it fires instantly.

 

Assuming--- hoping---- everything is rotating. Is the engine rotating? if it is, is the cam shaft rotating? Is the distributor rotating? Are ALL the parts and pieces installed and torqued in this "new" engine? does this new engine have all of the pushrods? All of the lifters? All installed? a mere presumption that if it has fuel and spark "something will happen" is only true if you have a known running powerplant. Before you go pouring anything anywhere verify everything, especially if it was a "professional" job. The last "professional" 460 ford that came to me with their so-called assembly job had rocker arms not even ran to finger tight- just fastener started in threads and thats it, not even ran finger tight and had I not caught it before and called and chewed some a$$. NExt was a 545 stroker that the heads were "race ready" I didn't triple check and guess what, a rocker loosened up and fell off and shot a lifter up into the valley. They had tightened the poly locks so far they had cracked one because of an underlyinig issue in the stud. Next is a mercruiser boat engine chevy 3.0l "NEW NOT REBUILT" --- PRODUCT OF MEXICO, piece of piston skirt was laying in oil pan, broken not on the thrust side, likely dropped during assembly. along with countless others from reputable suppliers we have all known of. It might not run if it was assembled poorly or not assembled at all.

The fundamental of an engine is if the cam is not turning but the engine is, (broken or missing timing chain, snapped key or dowel, missing chain wheel, who knows what. I have had experienced professionals argue and attempt to install a 460 timing set into a 400, "same same same its fine" If the cam is rotating in time with the crank shaft, properly, but rocker arms are not installed, installed too loose or too tight, or pushrods are missing or wrong, then i do not care what you pour in there, "Something" is not going to happen. Verify that the engine is rotating. if it is rotating, verify that the distributor is turning. Finally, someone is going to be smart and say "if it blew his finger off it must have compression so the valves must be working" Not true an engine that has no rocker arms installed will still blow your finger off while cranking. the piston comes up and makes air pressure enough definitely pop your finger. please follow up on this NEW engine with verified information as to what EXACTLY is or is NOT happening.

 

Luckily checking that should be straightforward. Pull the valve covers and distributor cap, then crank the engine over by hand and make sure all the bits are moving.

My guess is no spark. Hard to say without being there to look at things. Pics might help. My favorite way of screwing that up is getting the distributor out 180*

With gas down the carb, and the internals pumping properly, you should smell the fuel out the exhaust.

 

Did you replace hard parts besides seals and bearings? Things like cam, lifters, pistons, etc. I only ask as "rebuilding" can mean different things to people.

Spark in the presence of fuel and air means boom. You say you have fuel at the carburetor, even poured some in the throat. You say you have spark, but no fuel at the cylinders. Didn't leave any tape over intake ports or wrags stuffed in them did you? It is strange that it doesn't even pretend to start.