Rebuilt 351w question

I've been rebuilding a 351w for some time now and I've finally gotten to the point I can test it. I have it hooked up and mounted on an old harbor freight engine test stand. Last night I got it to fire, then promptly shut it down. The reasons are that when it fired it shot a softball size fireball out of one of the exhaust ports and it scared the bejesus out of me. The other is the stand is designed to use water from the house to cool the engine and I'm on a very finicky well. I can't even wash laundry without problems. So I'm wondering how long the engine can be fired up without water, I'm guessing none, and if i should put exhaust manifolds on it, which would shoot any fireballs at me.

I wouldn't run it for longer then 30 seconds every 10 min with no water ... but I wouldn't at all without headers, just saying

Why not just take a little time to fabricate a bracket on the stand to mount a radiator on to the stand? Then you can run it as long as you want! If you installed a new flat tappet cam in it specially a performance cam it needs to be properly broke in and running in short burst before cam break in isn't a good idea! And I would absolutely install a set of headers or manifolds on it before running it!

1. Regarding water, get a 40 gallon+ cooler and fill it with water. Put the intake and outake hoses into the cooler. You should be good for at least 5 minutes. You can also use a garden hose nozzle or clamp on the end of the outake hose to restrict the flow a little bit.

2. Regarding the 5 minutes, not sure how long it takes to seat the valves to the cam. I think it is 2000 rpm for 5 minutes, but your mileage may vary.

3. Make sure your ignition timing is working. Take off the cap, suck on the vacuum line and make sure your points plate rotates.

I wouldn't run it without headers or exh. manifolds. The breakin recommendation for my cam was 2000RPM for 20 minutes then change the oil (using high zinc oil).

I would create some type of water delivery system before breaking in the engine.

Make sure your distributor is mounted correctly. The fireball may be due to having inserted the dizzy one tooth off. Or it may be way out of timing, which could be determined by turning the dizzy each direction until you get some semblance of "smooth" running.

Why not just take a little time to fabricate a bracket on the stand to mount a radiator on to the stand? Then you can run it as long as you want! If you installed a new flat tappet cam in it specially a performance cam it needs to be properly broke in and running in short burst before cam break in isn't a good idea! And I would absolutely install a set of headers or manifolds on it before running it!

Click to expand...

1. Regarding water, get a 40 gallon+ cooler and fill it with water. Put the intake and outake hoses into the cooler. You should be good for at least 5 minutes. You can also use a garden hose nozzle or clamp on the end of the outake hose to restrict the flow a little bit.

2. Regarding the 5 minutes, not sure how long it takes to seat the valves to the cam. I think it is 2000 rpm for 5 minutes, but your mileage may vary.

3. Make sure your ignition timing is working. Take off the cap, suck on the vacuum line and make sure your points plate rotates.

Click to expand...

Two problems with trying to run a radiator. 1. I can't weld about the only thing i can use fabricate with my skill set is superstrut. Its expensive and i don't know if I can attach it to the stand. 2. I would also now need to put an accessory belt system on it.

I was thinking of finding a water tank and putting it on my hill, it's really high so I should get good pressure. Of course then run time becomes finite and then there's the problem of filling the tank.

This engine is a stock rebuild I'm doing mostly to practice building engines for future performance builds so the cam is unchanged for now. I lapped the valves but they are also unchanged.

I'm pretty sure the fireball was from the carb flooding the engine. There was a problem with the accel pump and when I fixed it I may have pumped it too many times. The system is using a duraspark ignition I wired in myself. Currently the only foreseeable problem is I don't have a resistor in the system so my coil will burn out if I run it too long. I'm probably going to by a dodge resistor from a parts store to fix that though. I have a spark tester on it so i know its working.

Heard ya on the manifolds I'm looking for some now. I was hesitant to put them on because of the way the stand orients the engine.

I was thinking of finding a water tank and putting it on my hill, it's really high so I should get good pressure. Of course then run time becomes finite and then there's the problem of filling the tank.

Click to expand...

Just recirculate the water in the tank by having the outtake put the water back in the tank...don't dump it out..

Heck, go buy a couple of blocks of ice and stick it in the cooler. At 2000 RPM you might not need that much heat removal...at least maybe not enough a few block of ice wouldn't take care of.

What is 8# of ice block, like $4??? Buy 8, keep 2 in the cooler. When they melt 1/2 way, add another...and keep adding blocks when they melt.

I think you'll be good.

AND GET THE ZINC OIL....VERY IMPORTANT...at least for ISKY cams.

Don't run it open port. SBF manifolds and shorty headers are soooo cheap and common, there's no reason to rik the exhaust valves, let alone your hearing.

I think a fireball video would be cool addition to the site.

I think a fireball video would be cool addition to the site.

Click to expand...

Daredevil....

I think a fireball video would be cool addition to the site.

Click to expand...

Daredevil....

Click to expand...

If you only knew. Lol

Tonight (4th of July) we prefer ground burst fireworks instead of the usual air burst. So we usually turn them upside down and then stick them into the ground. It is soooooo much better when the colors are exploding all around at ground level. We are careful about doing it this way but it only burns for a very brief moment if someone gets hit and we wear old clothes because they will get burn holes. That's the only danger to it...we are at least 15-20 feet away when the big explosion goes off.

The best part is it keeps the neighbors at bay because they know we like guns too and if we are that crazy with fireworks then who knows what we'd be like with a gun. HOA my arse.

Previous post X 10.

I have some manifolds now. I will be mounting them today or tomorrow. Timing is currently set at zero which will change once I have everything to keep the engine running without burning to the ground.

Looking forward to hearing how things go with the manifolds on and timing ready for adjustment.

The manifolds are mounted. Unfortunately solving one problem seems to have caused another. the passenger side manifold is now aimed directly at my Duraspark module.

Shorty headers for windsors are cheap. Cant get em for clevelands unfortunately

I just had a random thought. Can I swap side with the manifolds? Usually you don't want the exhaust sticking out of the front of the car but if they went forward instead of the conventional way neither the duraspark or me would get tourched

I just had a random thought. Can I swap side with the manifolds? Usually you don't want the exhaust sticking out of the front of the car but if they went forward instead of the conventional way neither the duraspark or me would get tourched

Click to expand...

I was just about to suggest to swap each one to the other side. Should work out for you just fine.

I still want a fireball video.

I though I should post an update. Both exhaust manifolds have been swapped so they now point out front.





My well has been behaving so I decided to give it a go and test the engine yesterday. I turned the water on and I immediately began leaking out of the front of the engine. Seems I outsmarted myself



This is the original timing cover for the engine. It's a serpentine cover since the engine is a 1990. (Cast code was 1989)



This is the v-belt timing cover off a 1986 302 that I used so I could test the engine using a carb.



And finally this is the serpentine water pump that I bought because "hey it's a serpentine engine" LOL.

The devil is in the details.