Are carbed I/O motors preferred by mechanics?

[Chris1956]

Had a discussion with some boat lovers New Years Eve. (We were all sober, BTW. ) They told me that some marine mechanics refuse to work on the fuel injected Mercruiser motors. They consider them too complex and unreliable.<br /><br />The question is has anyone else heard this? Also, can you still get most Mercruisers in a choice of carb and fuel injection? <br /><br />If so, what sells best, carb or FI?

 

[DHPMARINE]

Re: Are carbed I/O motors preferred by mechanics?

Sorry about your New Years (grin)We are a small shop,and have seen few FI problems to date.Don't really see a lot of carb problems either.Most fuel related problems are on both systems,due to h2o in the fuel.<br />Between Mercruiser and Mercury Outboards though,the company seems to be having trouble as to what format is needed for FI diagnostics.<br /><br />DHP

 

[Capt Ken]

Re: Are carbed I/O motors preferred by mechanics?

Nothing wrong with either. What you have is a case like back in the 70's when everything went electonic ignition. Most mechanics disliked and distrusted the system due to them not taking the time to learn. Same with the newer EFI's. Now what makes it difficult is you can't take your new EFI to just any mechanic like you use to. The equiptment needed to troubleshoot is very expensive and the shop has to justify spending thousands of dollars for maybe a handfull of engines that may show up in a years time. The day of the shadetree mechanic has passed. The dockside or mobile mechanics who are not associated with larger dealerships won't have access to the equipment or the computer programs that will be needed in the upcoming years. The newer "everything is now run by a computer" engine is very dependable if proper procedures are followed when repairs are made. I saw an article from Yamaha about the future at our last Update school where possibly in a few years they will have their own version of OnStar. If the boat owner is having problems with his engine the data can be transmitted via satellite to Yamaha where it can be downloaded, problem located and the information passed to the nearest dealer for quicker repairs.

 

[newport dave]

Re: Are carbed I/O motors preferred by mechanics?

EFI all the way for me. Cause this (below) is way more fun than working on a carb'ed motor!<br /><br />Dave<br /><br />

 

[Buttanic]

Re: Are carbed I/O motors preferred by mechanics?

I have been a shade tree mechanic all my life. When electronic ignitions and computers came into use I did my homework to be able to work on them. I have not taken a vehicle to a mechanic for repair in over 30 years. The new systems are great but I still will not use them in my boat.<br />When I am 30 miles off shore I want something simple that is easy to trouble shoot and fix without high tech diagnostic equiptment. The new electronics are very reliable but when they go bad you best hope you are near the dock<br />and not 30 miles out. Newport Dave, you bring that diagnostic machine and a box full of parts on the boat when you go out.

 

[Boatist]

Re: Are carbed I/O motors preferred by mechanics?

I am also just a shade tree mechanic but I would not buy anything but a EFI or MPI today.<br />The benefit just far out weighs the risk.<br />It is a true turn the key and back it off the trailer.<br />No checking the choke to see if it is stuck open or closed.<br />I have spent far less time working on my cars with all the new MPI engines.<br />I would say 3 times as relibable. Also better fuel mileage.<br /><br />Do you trust it with your life? NO That is why you have a second engine for off shore.<br />I would not trust a Carb model with my familys or friends life either.<br />A kicker will get you in safe if set up right.<br /><br />Carb models it is start it and warm it for five minutes,<br />then hope it does not die when you kick if in gear.<br />If it does not start right away you wonder if you flooded or it did not get enough fuel.

 

[Sea Six]

Re: Are carbed I/O motors preferred by mechanics?

There's a lesson to be learned from the automotive industry. NOBODY uses carbs anymore.

 

[piratedude]

Re: Are carbed I/O motors preferred by mechanics?

efi is great in cars but read other posts about the problems w/boat efi. look at newport dave post. everybody i know who has bought a efi boat has been sorry they did. $$$ and time in shop not counting breakdown at sea makes simple better. fuel injectors alone are @ $75 apiece. yes they do run good and have slightly higher hp when they run but when they break, break hard and $$$. boat mechanics love em...pays for their new corvette!

 

[WillyBWright]

Re: Are carbed I/O motors preferred by mechanics?

If you can find a marine mechanic that can afford a CORvette, give me the name of the place he works for! More likely we drive a CHEVette. <br /><br />I find the EFIs much easier to operate and no more difficult to work on save the diagnostic equipment. A lot of people have no concept of how to operate a choke anymore. Many have never had one since cars have been EFI for quite awhile now.<br /><br />If you can find ANY MerCruiser dealer that shys away from EFIs, GO SOMEPLACE ELSE!!! There are those that rarely send their mechanics to school and those are the ones that cling onto old technology. The independents have a harder time procuring the test equipment, so if you do get an EFI you'll be kinda stuck having Dealerships work on them except for routine maintenance. You'll have to do a bit of shopping around, but if all you see is I/Os with 3Ls in stock you might want to check out others. Those are about the only ones available anymore with carbs and I hear they're going EFI as well.

 

[newport dave]

Re: Are carbed I/O motors preferred by mechanics?

Originally posted by Buttanic:<br /> Newport Dave, you bring that diagnostic machine and a box full of parts on the boat when you go out.

Well no, I normally woundn't bring my computer and engine analyzer on a normal day on the water, but to do so would not as impratical as it sounds. It's just a laptop and another smaller box. The Mercruiser Smartcraft equipped engines with the on-board display can monitor many of the same functions as a laptop, and they are always on board.<br /><br />Your point about the advantages of owner/user servicability is valid. But you still have to bring tools and parts and know how to troubleshoot. Also, consider that a computer controlled engine can protect itself from major failures, and a carbed engine cannot.<br /><br />The days of the carburetor are numbered. At least as far as new boats are concerned. Mercruiser, for example, has only four engine models left with carbs, and they are all two barrel models. <br /><br />Starting January 1, 2003, emissions requirements for marine engines (at least here in CA) began. By 2007, oxygen sensors and even catalytic converters may be required. Non computer-controlled (carbed) engines will simply not be able to meet the requirements.<br /><br />As a marine tech, independant (like myself) or otherwise, you will have to chose to fight it (like those mentioned in the New Years Eve discussion) or embrace the technology. It's a losing fight.<br /><br />Dave

 

[marinemech]

Re: Are carbed I/O motors preferred by mechanics?

your boat is for you not the tech<br />efi is now the only way to go a<br />gm doesn't make an engine with a carb therefore all of there r and d is on efi<br />all said up grade to a outboard or a volvo penta let the black stay back

 

[highaltitude]

Re: Are carbed I/O motors preferred by mechanics?

a dead battery is a dead battery. a good boater will always take a paddle. both carb and efi will work as designed.

 

[Boatist]

Re: Are carbed I/O motors preferred by mechanics?

Most people said the shad tree mechinic can not work on a car with EFI or MPI also.<br />I find it much eaiser even with nothing but a paper clip it will tell me whats wrong.<br />All my car you can ground a point on the test block and it will flash the error code.<br />Look up the error code and it will tell what the trouble is.<br />If you bought the book you will fine a trouble shooting procedure.<br />Yes it may say the EGR valve has a problem or the MAP Sensor or oxygen sensor.<br />Yes it may suggest you run a test but it also says check this voltage or the restistance.<br />At least you know the the general area of the failure.<br />With the Carb model all you know is it does not run.<br />Sure with a little knowledge you can determine if it is fuel, spark, compresion or timing.<br />I think with the equipment mechanic should be able to fix it faster.

 

[Buttanic]

Re: Are carbed I/O motors preferred by mechanics?

I agree that EFI can be easier to diagnose with the onboard diagnostic on most new cars, and most systems have some sort of limp home mode. But my problem with using them in boats is they have to live in a much more hostile environment, especially in salt water. How many carry a spare computer module, because if it goes you are dead in the water. Also if you carry one you must be careful when making the switch that you don't accidently fry the spare if there was a problem else were that caused it to fail in the first place. On my carburated, point ignition engine a kit of spare parts that will cover most any problem short of a gas tank full of water can be put together for less than $100. A spare computer alone will cost at least 3 time as much. For those who don't do any type of repairs themselves it doesn't make much difference if it's EFI or carburated, you call the tow service and take it to a tech. But when I am 30 miles offshore I want to feel I fix most any problem that may happen and keeping it simple is the way to do this.

 

[jimmythekid]

Re: Are carbed I/O motors preferred by mechanics?

point ignition???? whats that?? <br /><br />EFI= longer engine life, much more fuel efficient, less polluting (the best reason) very easy starts<br /><br />i have a carb on my boat, but givin the chance I would take EFI hands down

 

[waterone1@aol.com]

Re: Are carbed I/O motors preferred by mechanics?

This is one of those threads where everyone has a valid point. Long before I was working on boats, I was working on corvettes and cadillacs. Those two car "platforms" had more electronics than just about everything else combined. On one hand, once you get the education and practice to troubleshoot them, it's not that big of a deal. Yes, you will get more horsepower, better fuel economy and lower emissions......but I Have to agree, just a little too much salt water in the wrong place can leave you stranded. But lets face it, whether anyone likes it or not......mpi and efi are where things are going....get used to it.

 

[Stan's Customs]

Re: Are carbed I/O motors preferred by mechanics?

Like it or not EFI etc is where things are going for sure. Most young mechanics will never even know how to deal with the old ignitions and carbs before long...in fact many don't now. Electronic diagnostics and palm pilots are a way of life...fun if you will, for the younger set. <br /><br />Nothing ruins a hard earned vacation like a boat break down early on. Long way from home,it's a Holiday weekend or Sunday and you could'nt buy parts on a bet.. you're out in the water at the end of a rope and the boat quits when Mama hammers it.....dead and ain't gona start. Bad day in Mudville unless you got something simple to fix. Been there ...won't happen to me but once. <br /><br />That was years ago.... however I just bought new points distributor for one of my boats. I wouldn't have anything but a Quadrajet...so there you go. Bottom line to me is ...run what you can keep running best and cheapest. Usually it boils down to what you know the most about....in my case the one I know the most about is also the simplest. Simple is good sometimes......especially if you plan on being 30 miles out......

 

[mellowyellow]

Re: Are carbed I/O motors preferred by mechanics?

prob. easier to find a wrench who has "years" of<br />experience working on MY carbed '76 140/4cyl...

 

[Chris1956]

Re: Are carbed I/O motors preferred by mechanics?

Thanks for the opinions and insights. Now I have another observation. It would appear that I/O motors although they are based upon automobile engine technology, lag behind in getting the technology updates. For example, automobile fuel injection started to be standard on most autos by mid 1980s. I/O motors didn't start to get fuel injection until the mid 90's. Alternatively, outboard engines received technology updates before automobile engines. For example, a 6 cylinder 1978 Mercury outboard had distributor-less ignition (ADI), and had CDI Ignition for 6-7 years already. A 1971 auto had points and autos in general had mechanical distributors until the late 1990's. <br /><br />Any comment on this?

 

[outboardguy]

Re: Are carbed I/O motors preferred by mechanics?

Do you think Mercruiser,Volvo,and Omc wanted to go to EFI,MPI,DFI. Probably not.The reason they changed is that they were forced to change.If you were a big marine manufacturer would have shelled out the big bucks for EFI in the 80's.Nope it's much easier to stick with old technology and sell more units for a bigger profit.These days they are being forced to meet certain emmission requirements and are willing to spend the extra money to stay in business.In todays society people don't mind spending the extra money on an engine that they know will be cleaner for the environment.