New engine startup issues...

[aarvig]

Hey guys...I have a DART block 427W that was professionally built and run on the dyno. My build took 5 years to get to the point of driving so when I went to hook up the throttle I discovered a bunch of carb problems due to it sitting for so long. I had the carb professionally rebuilt as a result. I started the motor for the first time this weekend. Initial startup was great. Started right up and needed a little idle adjustment other than that ran fine. It ran so well that I took it for a couple spins around the block. After about the 3rd loop (I was driving with the air cleaner off) I got a bunch of gas that splashed out of the carb and hit the windshield. From there that led into an overheat (temps got up to 230F) and the engine quit. Was able to start after a few minutes, got it home, it quit again. Restart, temps started coming down to normal (added coolant) and returned to normal running and idle. However, I had a bunch of dieseling when I went to shut it off.
Fast forward a couple of days...started it again this morning and ran really rough, wouldn't stay running, backfired, and even started a little fire in the carburetor. Decided to leave it off after that.
Its got a Quickfuel 4 barrel with electric choke. It has a pertronix electronic distributor with no box.
Initial timing is set to 9.5, total timing set to 30.
The other issue I noticed is that the engine will continue to run when I turn off the electrical master. Not sure if this is normal behavior or not.
Anyways, I am wondering if I have a needle and seat problem, float adjustment problem (gas splashing out of the carb), an ignition problem or if the 230 degree heat fried my motor somehow (can't imagine that is the case but you never know).

[Fman]

FWIW on my dart 427 my timing is 16 base, 32 total with a mild cam. I would contact your engine builder and ask what he recommends. 9.5 sounds too retarded to me but maybe this is where you should be. Your dieseling and backfiring could definitely be timing related.

For cooling make sure and burp all the air out of your system. Amazon sells a $20 kit that will take care of it. Also dont let your overflow run dry because it will suck air back into your cooling system and you will be back to zero again. Assuming you are running a 50/50 mix for coolant? 20 lb cap?

230 will not damage your engine, although definitely on the hot side. I'm running around 190 on average for temps.

Here is a link for burping system
https://www.amazon.com/Thorstone-Radiator-Multiple-Adapters-Vehicles/dp/B085759CPH/ref=mp_s_a_1_2_sspa?dchild=1&keywords=coolant+burping+funnel&qid=1622585601&sprefix=coolant+burping&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFHRkU1WEgzVlQzNzYmZ W5jcnlwdGVkSWQ9QTAwMzQ5MDYzQkE3QlI4R0RONUZKJmVuY3J 5cHRlZEFkSWQ9QTAzNDkzODAxUTlORU0yMTBIRDZCJndpZGdld E5hbWU9c3BfcGhvbmVfc2VhcmNoX2F0ZiZhY3Rpb249Y2xpY2t SZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=#

[CraigS]

If you can keep it running long enough get to the carb and look down in it as it idles. Also look at the fuel level sight glasses. I am wondering if the needle/seat is leaking or the float sunk so it is pouring fuel in faster than it can burn it.

[rich grsc]

JMO, but 16* is a little too much for a 427, and 9.5 is too little. I would think 12-14* would be a good starting point. But each engine likes and runs what it likes.

[GTBradley]

If you can keep it running long enough get to the carb and look down in it as it idles. Also look at the fuel level sight glasses. I am wondering if the needle/seat is leaking or the float sunk so it is pouring fuel in faster than it can burn it.
Just don't rev it while you're looking down it - when I was 16 I found out the hard way that's a good way to become eyebrowless.:mad:

[Gordon Levy]

Set your initial timing to 12 and see if you have a total of 33. Any more than that is pointless. Check your fuel pressure, 7-8 is normal. More than that and you can push fuel past the needles.

[aarvig]

Thanks for the replies guys. It has an Edelbrock 1725 mechanical fuel pump on it. That pump is supposed to only max out a 6 psi. I don't have a fuel pressure gauge on it but I suppose it is worth a check. I did remove the carb yesterday and sent it back to the carb shop that rebuilt it. They are going to check it over. Once its back on the car I am going to bump the initial timing to 12 as Gordon recommended-maybe even up to 16. Several people have told me to go to 16 but Gordon is an experienced pro...so I'll start at 12 and work my way up.
Has anyone ever heard of a mechanical fuel pump breaking and causing excessive fuel pressure?

[Norm B]

If you still have all the spec sheets from your engine build the cam card should give you a recommended timing setting. If not then 12 degrees should be a safe starting point. I would pull the plugs and have a look. Might tell you something.

Norm

[Avalanche325]

Since you have been spewing fuel, pull the dipstick and give it a sniff. If your oil smells like gas, change it soon.

[aarvig]

If you still have all the spec sheets from your engine build the cam card should give you a recommended timing setting. If not then 12 degrees should be a safe starting point. I would pull the plugs and have a look. Might tell you something.

Norm

I did pull the sheet and it calls for 10 degrees of initial and 28 of total. Currently set at 9.5 and 30. Called the tech folks and he told me the timing should definitely be set to 16 intial and 30 total. I'll get that adjusted once the carb comes back. Whats weird is that it ran great for about 5 miles and then went to crap. I'm banking on it being some loose crap in the new fuel system/tank etc that got in there during the build process and plugged or blocked somthing in the carberator.

[Avalanche325]

One of the best things I did while tuning was to put advance limiters on. I was running a little too retarded at idle for my full advance setting. It really helped with idle consistency and cold running.

[aarvig]

UPDATE:
Yesterday before taking the carb off to send it in I was checking the electrical connections to the electric choke on my carb and got burned when I touched the choke cover. It was hot as H E double hockey sticks. Took the carb in and the builder found a stuck needle and a fried choke.
Getting a complementary overhaul on the carb again-excellent customer service. They are installing a new choke and we should be good to go. I'll report back once its on the car and running.

[Gordon Levy]

The car and key were off and the choke was hot it is getting constant power and not wired correctly.

[aarvig]

The car and key were off and the choke was hot it is getting constant power and not wired correctly.

It is wired to key on power. When the ignition is off there is no power to the choke. I had the key on checking the choke function. Grabbed a hold of the connector to wiggle it and make sure it was tight and burned the heck out of my finger...