rangerrick63

Been doing some boat shopping, I've sorta narrowed my selection down to a few.
The power varies between them (of course), & this has me "on the fence" so to speak. I like the simplicity of a carbed motor, but do I lose reliability that the EFI has. But then I go back to all the issues I had last summer with my Donzi, & the fuel system from an EFI motor.
I suppose I'm old school, from my days of playing with street rods. A carbed motor is easy to work on, not much to really go wrong with them, it's just the constant "tweaking" & "adjusting" to keep them running just right. Is that the same case with a marine carbed motor?
I guess I'm looking for insight from folks that have run or are running carbed motors, how do they do, overall, compared to an EFI.....Thanks....

Brad Zastrow

I have one of each now 525 EFI and a carb blower enigine. The EFI is real nice at startup and is easy on gas. However they can be a pain the rear when a sensor fails. I like both however. Carbs are bulletproof and make a lot of power but a little rougher at idle when cold and will use a little more gas. MUCH cheaper to do a carb setup.
Right now I am chasing down a EFI problem on one engine with a buzzer going off all the time. Twice they can not find the issue when hooked up to the computer.

In summary EFI is really nice when it works (all cars have it)and carbs are real simple and make just as much if not more power.

Griff

I agree with Brad. I like the efi for its easy starts and idling. I like carbs because they are simple and easy to upgrade. I will more than likely switch out my 502mpi's for a set HP500 carbed engines if/when I make the switch sometime in the future.

rangerrick63

That is my thinking, there are not many "issues" that can happen to a carbed engine, that you cannot somehow get it home (short of major failure). I mean, a carb can even be somewhat overhauled on the water, if needed.

Last summer I sure had my share of EFI woes, nothing real serious, just quite frustrating. I was never brought back to the ramp via tow rope, so I guess that is a plus ...but troubling none the less.

I will most likely go with the carbed HP motor set-up, it doesn't have the "cool factor" that a 500EFI, or a 525 has, but I suppose the trick is to keep the hatch closed....lol....

Thanks for the input....

Big Time

I've been looking for a new boat too and have come across the same question. Can anyone speak to the maintanance on either of these. I guess my question is specific to the old carbed HP 500 and the newer 500 and/or 525 EFI's....will both need to be rebulit at around the same number of hrs? Any other differences that I should be aware of?

Canada Jeff

EFI in stock form is far better than a carb engine. EFI has sensors to monitor if the engine is knocking, and then emediatly retard the timing. Bad fuel can take out a piston or valve. At least with EFi you have a far better chance. Some EFI's have a protection mode so if something does fail (sensor), you can limp home, without hurting the engine. MERC has gone EFI though out there line up for a reason. You don't see many custom builders doing EFI purely because they don't educate them selfs or invest in the technology.

Fuel efficienty, cold ideling, easy shifting without staling, incorperating electric throttle and shift (merc system), plus all the bennifits of Mercs new Smart Craft system.

My opinion. It's the way of the future, H ell it's here now, no one can argue that!

Griff

No real differences with regard to rebuild intervals. Carbed 500HP's just need to have the valve springs done by 200 hrs. The others need them by about 300hrs.

Griff

One bad injector will take out a piston just as easily and the ECM won't stop that. You can also install a knock sensor on a carb engine.

rangerrick63

Picking up on the idleing & shifting issue you mentioned. Is that an issue with a carbed engine, that it tends to stall when shifting? Or is that a "cold engine" issue?

DMOORE

Yep. Just aks my buddy with a hole in a 496HO piston.


Darrell.