Need help on my 1995 Volvo Penta

[Cobalt222]

Hi, I have a 1995 Cobalt with a carbureted 7.4L GL. The carburetor needs rebuild or replacement. I want to swap the carb out for a throttle body EFI system and trying to find options. So far, I have only found the Holley Sniper system. Anyone have any experience with this type of project or any suggestions? Thanks

 

[jimmbo]

That system requires an O2 sensor for feedback That complicates the matter somewhat as the manifolds are water cooled and as the exhaust exits the manifold elbow, water is then introduced to the exhaust. Holley makes several EFI systems. It would be worth the time to call Holley and Edelbrock, explain what you would like to do and see what they can offer in a non feedback system.

 

[Cobalt222]

Thank you. But I called Edelbrock and they have no marine systems available and when I talked to Holley, they said, as you just did, that I need an O2 sensor. They suggested Howell who has an adapter for the O2 sensor. I looked it up and I can probably install the O2 adapter myself. Though I was hoping for more options for throttle body EFI kits from different companies. Not impressed with Holley.

 

[Lou C]

Honestly you would be better off as far as repairability, by just getting a new carb. If the engine came rigged with the Holley I'd either rebuild the original or replace it. Keep in mind that an EFI system requires an ECU and sensors, and this is often where the troubles start in a marine application due to the exposure to moisture. Also, if the system gets discontinued, you can be out of luck if you need an ECU 5 years later. A well set up Holley should give good performance on that boat, and they can be easily rebuilt because marine mechanics are familiar with them and all the parts are available from Holley and the aftermarket.
If you get the model # off of the air horn and call Holley they can probably tell you the exact model that was used and what to replace it with....

 

[Cobalt222]

All really good points. I'll have to think this through. I'm just tired of dealing with temperamental carburetors, especially when going to high altitude lakes like Tahoe. Thanks for your input.

 

[jbuote]

Not a pro here in the least, but ...

I'm just tired of dealing with temperamental carburetors, especially when going to high altitude lakes like Tahoe.

You don't say where you normally are.
Do you often switch between low altitude and high altitude lakes?
Depending on the change, the jetting could be wrong, mixtures etc...

Just as a thought..
Would it be feasible to set up a carb(s) for the low altitude and have a second set for the high altitude?
That way, you could have a good setup or lower altitude, and another for higher altitude..
Maybe it's just a set of jets and you do the swap based on altitude..

Again, I'm NO pro...
It's just a thought that occurred to me when reading this.
Not sure it'd be worth it, but I'm guessing you and the others might know where I'm heading with this, and can guide you better if such a thing is worthwhile..

Edit: Sacramento is about what? 32' above sea level, and Carson City on the other side of the lake is 4,802' above sea level..
With Tahoe being at 6,224' above sea level, there may be changes needed...
Maybe I'm way off base with this, and I apologize if so..
Again.. Just thoughts..

For what it's worth..

 

[jimmbo]

You think carbs are a pain in the butt to troubleshoot. They are easy compared to the mischief and headaches a FI system brings to troubleshooting, diagnostics, and repairs. Give me a carb any day.

Jets, power valve calibration, Secondary opening calibration, are some of the calibrations that might need changing/adjusting when there is change of over 3000 ft. The Holley 4bbl is an easy carb to clean, reassemble and check/adjust tolerances.

 

[Scott Danforth]

Spend $35 on a carb kit, or spend $2000 on an efu system. If you cant figure out a carb, you wont figure out an EFI

Swapping jets for higher altitude takes 10 minutes and that is with cleanup

 

[Lou C]

I have found that Holley has pretty good tech support depending on who you get. Explain to them that this boat is used at altitude and they may be able to suggest a compromise on the jetting that will work better. Keep in mind that as you go up in altitude, your fuel mixture will become richer if it has been calibrated at sea level because the air is less dense at altitude. You therefore need less fuel to maintain the same air/fuel ratio. At least the Holley is a lot easier to work on than the Quadrajet that some OMC's had. However, on a 20 year old boat, I might be replacing the carb if it can't be cleaned properly or if there is corrosion inside.