Well I just finished putting in my new engine. I primed the oil pump and fuel pump but not 100% sure if I did this correctly and when I went to start it, the engine turned over before I heard a very loud pop...I assumed it was back firing from old fuel in the engine (I couldn't tell as I was inside the driver seat)

I tried again and this time it started like it should but with alot of grey smoke from the fuel and seeing this I chickened out and shut off my engine.

Started it again and it struggled to turn over and this time another loud pop before I shut her down.

The final attempt the car struggled to turn over and when it eventually did it sounded like the car was running off one rotor as the car was shaking and all

Please don't tell me I blew the engine? I'm assuming there wasn't enough fuel in the car to begin with so did I blow a seal or something?

 

a fresh rebuilt engine or one that you find in some friend house sitting for a long time?

 

It was from a front clip i bought so not too sure how long its been sitting for. Couple of months I'd say.

 

I've checked my plugs and they smell of gas so I'm going to do the unflooding procedure. Is there anything else I should do before I try starting her again after this?

 

The popping could be from fuel in your exaust igniting. Turn your engine over several times with the fuse removed to get some of the extra fuel out, I think this is part of the unflooding proceedure you spoke of, clean the spark plugs, and put some atf in the spark plug holes. This will cause a lot of smoke, so don't panic, but it will give you compression at startup. Keep an eye on the exhaust so that it doesn't overheat due to a clogged cat. My cat clogged after restarting with a new engine I think due to all of the fuel in the exhaust. Also make sure everything is hooked up right. The guy helping me had plugged in my coil igniter harnes incorrectly whiched caused issues. Luckily it didn't blow the engine.

Good Luck, don't panic yet.

 

Cheers for the info. I'm not in panic mode yet but close to it. Can someone reassure me that you can't blow an engine by starting it?

I want to at least sleep at ease tonight.

 

You can't blow a good engine just by starting it, assuming that the system has oil and coolant.