1975 351w not moving

I got a 1975 E150 Van with a 351w and a C6 in it. I left it for about 3 weeks and the temperature dropped from like 40s and 50s to like 20s and 30s.

Now it wont start or move by hand.

I know it may have had a loose timing belt with a rough idle.

I know the transmission leaks from the bell housing. I inspected the flywheel where the starter stopped and it slightly round, but doesn’t seem like it is so bad to stop the starter from turning it. I checked one plug and have spark. The battery is good.

This is the series of events…

I got in it and cranked it. I slammed the starter once and have since replaced it. The starter gears were worn. It kicked over a little bit but wouldn’t start up. It was leaking gas out the bottom of the carb and flooded.

I replaced the starter and rebuilt the carb. Charged the batteries. Pulled two plugs. One was wet with gas.

It would turn sometimes over then stop. Now completely stuck. I’ve pulled the plugs and can’t move it by hand either way.

I’m thinking the valves are stuck or the timing belt is wrapped around the gears or something… Any ideas?

Try turning it over by putting a breaker bar and socket on the crankshaft pulley there is no timing belt on this engine it uses a chain.

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Might be hrdrolocked, pull all the plugs, then see if it will crank. It may spray gas through the spark plug holes. Check you oil level, gas may have drained into the crankcase.


So it sounds like he pulled all the plugs and tried to turn it over with a wrench, no go. So could be the timing chain is jammed, I guess.

I am not a mechanic so I don’t see a lot of timing chains but the ones that I did see were stretched just enough to cause it to be out time and not broken it seems to me that if it was stretched enough to jam it would have to be broken right.

The cylinders have been washed with gasoline, this will cause a lot of friction with the rings in the cylinders. Give each cylinder a squirt of motor oil.

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I missed that, saw he pulled two plugs, overlooked the second comment that he pulled plugs.

If the oil in the cylinders doesn’t work, you might remove the starter and try to turn the engine by hand. May not be plausible, but I’m wondering if the starter might be locked against the flywheel somehow, preventing the engine from turning. Not sure if that’s possible, so if it’s not, correct me. I’m thinking it might be possible with a cracked or badly damaged flywheel.

Sprayed PB Blaster into the cylinders twice in intervals while trying to work the engine from the front. Not budging.

Now attempting to get to the timing chain… I know it is plastic, so maybe it did completely fail…

Old and the carb was a little rusty by the throttle, so maybe something is rusted stuck…

Thank you.

Ford 351 Plastic timing gear - YouTube

Common problem with Ford carburetors was the power valve in the bottom of the float bowl leaking so that could explain gas down low. Same principle with Quadrajet carbs; jet well plug leaks.

It could be that the starter motor ramming the pistons against a hydrolocked cylinder took out the timing chain gears and/or snapped the chain. If the timing cover is removed, check the coolant ports (facing the block) carefully for severe pitting. This is a common problem and you may need a new cover.

And check the trans fluid level. Sounds like a front pump seal leaking and that can get away from you very quickly when it comes to fluid loss.


Doesn’t a 351W use a timing chain rather than a timing belt? If the timing chain has jammed it could explain this symptom. Best not to force it to turn if you think that’s the problem. You might could gain some clues by removing the dist cap and watching the dist rotor as you gently try to manually rotate the crankshaft. I think the way it works, the crank shaft turns the timing chain, which turns the camshaft, which turns the distributor shaft, which turns the oil pump. If you run out of ideas what to do, suggest you remove the timing chain cover next.

Fuel leaking from the carb into the intake manifold could be a defective power valve.

Worth trying to free it? Taking the top cover off? Don’t really have the tools for pulling the pulleys right now…

Watch the video on the plastic covered timing gear teeth again.
If you can not turn the engine with a breaker bar with the spark plugs removed, that timing gear cover has to be removed. Sorry to say but there is a possibility the engine is toast.

I was surprised and baffled that Ford and GM did such a thing to make there engines quieter.

autozone and a lot of auto parts store have a free loan a tool program. you leave a deposit and get it back when you return the tool.

Oil is thick. 10w30 in it…

vacuum port under the automatic choke was opened unfiltered

Plan to rebuild by taking the van to the diy shop and pulling the engine and transmission…

The port that’s located sort of under the auto choke on my Ford 302 isn’t for the vacuum. It’s called a heat riser I think, heat from the engine goes through that path to close the choke sooner, helps control the fuel mixture & reduce emissions. There is a vacuum component I guess, as the engine vacuum is what pulls the heated air through that circuit. But I don’t think if that was left open it would cause a vacuum leak, at least not enough to affect engine performance. It being open could allow dust/dirt into the carb though. Normally the air in that circuit is first cleaned by the engine air cleaner, then down to the exhaust manifold cover, and the warmed air goes back to the choke.


The one to the left of the fuel inlet is what I’m talking about… carb had a good layer of sediment in the fuel bowl of sand or rust. Yes, was leaking near the power valve.

Broke down a bit out of the way… I wish I had easy access to power for the block heater. No plugs nearby.

Gonna have someone look at it and bring a big pry bar to try to work it from the flywheel tomorrow…

That looks more like one of the the vacuum sources for the distributor’s vacuum advance. Below the throttle plates.

Took the inspection plate off. Flywheel looks good. Planning on having to rebuild or replace the motor. Want to take the heads off next. Got to the valve cover and everything is basically old and rusty…

Will the motor come straight out of these vans with it on the ground?