Rebuilt 502 with new carb problems !! Help !!!

[Longstoryshort]

I just got back my 502 from a full rebuild . Had a major leak down in a couple of the heads. With the new rebuild , did a new carb. Went with the Brawler 850 . Unfortunately, I wasn’t able to get to get the boat motor dyno in time before our Havasu trip . Went out today to Elsinore to water test it and was out there all day !!!

Motor started fine, tuned and timed it. Once I put into gear , boat died. Did that like 5 times . Pulled it out of the water and check the new plugs . There were fouled . Got new plugs and locked out the distributor. Went back in and the same but a little better . We were able to get it out past wake and it ran ok at high rpm ! 50-65 ish . Idle and bottom end is terrible ! Can keep the boat running. Please help ! Called a distributor guy in Havasu , hopefully he can save our trip for the weekend . Please help anyone ! Thanks

 

[port austin pirate]

make sure your not a notch off on the dist to number one, have you set the float levels in the carb and have proper idle settings also check acclerator pump shot and what size shooters they are also may need to check main jet size as well just a couple things off the top of my head some of the real mechanics on here will probably be along shortly to give some better suggestions. one more can check that spark is hot enough and make sure all connections are tight

 

[LOBOATOMY]

Engine Masters last Friday, how to tune a carburetor, may be worth finding it streaming for carb setup.

Also O2 sensors are a must for tuning a carb motor and to keep it running.

 

[rivermobster]

I just got back my 502 from a full rebuild . Had a major leak down in a couple of the heads. With the new rebuild , did a new carb. Went with the Brawler 850 . Unfortunately, I wasn’t able to get to get the boat motor dyno in time before our Havasu trip . Went out today to Elsinore to water test it and was out there all day !!!

Motor started fine, tuned and timed it. Once I put into gear , boat died. Did that like 5 times . Pulled it out of the water and check the new plugs . There were fouled . Got new plugs and locked out the distributor. Went back in and the same but a little better . We were able to get it out past wake and it ran ok at high rpm ! 50-65 ish . Idle and bottom end is terrible ! Can keep the boat running. Please help ! Called a distributor guy in Havasu , hopefully he can save our trip for the weekend . Please help anyone ! Thanks

This is a blower or super changed engine?

Where is the carb that it ran with before?

 

[obnoxious001]

What did you do with the idle air screws? Summer air is hot and thin, needs a lot less fuel to idle correctly. I just went and adjusted carbs on a blower engine I built that had been dynoed in winter months. 5 minutes I had my friend smiling.

 

[pickleforkcanuck]

If it isn't a blower application, single carb, I would look into primary power valve, not sure what brawler comes with but maybe to high a number

 

[4Waters]

To be honest I've never had much luck tuning aftermarket holleys especially BG (reason why he was the only one running them in prostock) I'd go with factory holley