Wrong Carburetor??? Holley V Weber

[ekeef01]

Have a '94 5.7 350 Mercruiser engine. It originally came with a Weber 4 Barrel 750cfm carb. Unfortunately the metering rods went out on it and I replaced it with a Holley 4 Barrel Carb. Could this cause me to run lean on my gas, cause a knock, and horrible engine performance? I can barley get the secondary's to open on the holley and I have the lightest vacuum spring in it. Just want some other opinions before I drop 400+ dollars to get the Weber rebuilt. Thanks!

 

[SeanMcl]

Re: Wrong Carburetor??? Holley V Weber

I replaced it with a Holley 4 Barrel Carb. Could this cause me to run lean on my gas, cause a knock, and horrible engine performance?

Holley carbs use a Power Valve that open to add fuel at a given manifold vacuum. If you have a PV that is wrong for your application you will have poor performance and either run lean or rich, depending. Incorrect jets will also cause you grief. I would get the list number off the choke horn, call Holley tech support and ask them what jets and PV you should be using. It's not so much the name on the carb as it is getting the carb setup for your application

All this assumes you are not using a carb that is all gummed up or isn't made for marine use. If that's the case all bets are off. Marine Holleys use different jets and PV than auto, due to the different load characteristics. Marine carbs also are less likely to burn your boat down to the waterline.

 

[ekeef01]

Re: Wrong Carburetor??? Holley V Weber

Thanks for the info I will give that a try and yes it is a marine carb that is clean.

 

[jtybt]

Re: Wrong Carburetor??? Holley V Weber

Holley makes a number of 4 barrels. You gotta ID the model before anyone can give you definitive answer to questions.