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"I've got to give my merc

"I've got to give my merc 470 a thumbs up guys. while I will agree it is an odd set-up, and I had to add another joint in my fore arm in order to reach everything to winterize the heat exchanger, she starts every time, runs beautifully, and gets my 19 1/2' century to 42 mph with only my skinny carcass in it, and the fuel consumption is light. I see nothing to make me fear this motor.

I am just a back yard tinkerer with a mercruiser manual, chainfall, and old oak tree, but this motor when properly cared for and paid attention to can give alot of reliable service.

I watch my gauges, and go through a checklist the night before I head out, just a routine check to make sure all is good. That should be a part of any boaters prep. While there are lemons (no matter size or name brand) I find alot of motors die just because of neglect and abuse, then they get pawned onto some unsuspecting boater who doesn't ask for a test drive before making a purchase.

just my 2 cents"
 
"Swift Jeffy - you and I agree

"Swift Jeffy - you and I agree on this. I'm almost afraid to brag on the old thing, for fear it will go haywire next time I go to run it. Mine's a 1979 and I am the third owner. It has its quirks but all in all I can't complain. I hate working on the outdrive, but I suppose they are all similar. This is my only I/O experience so I really can't compare.

A few years ago on the first Spring use I didn't realize that the impeller was shot and the exhaust bellows about caught on fire, burned the trim and limit wires, ruined the water-cooled V rect, and scared my wife into jumping onto the first boat that come alongside. When the smoke cleared I had a lot of work to do. Replaced the rect with a new belt-driven alternator. Installed a water pressure gauge where the old rect was - on every crankup I check that gauge and feel of the exh manifold, just to be sure the pump is working. Thinking of installing a washing machine water level switch to a horn on the dash. Or to kill the ignition, or both. (Oh, oh, I have mentioned a non-marine part! I will be sure it is explosion-proof.)

This has been a long and informative thread. You know, if would be nice if we could agree to disagree without being disagreeable.

Cheers and have fun on the water. JW in Dixie"
 
"Just remember, if anyone asks

"Just remember, if anyone asks, Larry Whitehead started this whole rigamaroll!
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"And, Larry never really defin

"And, Larry never really defined "needs a little work" or told us what parts he wants to replace."
 
"I do not want to reignite the

"I do not want to reignite the old arguments etc, but I do find the whole auto/marine parts issue interesting.

I also want to be clear that my previous post was not intending to disrespect anyone, or fan the fire etc.

Anyhoo 470 or any other model I have found that many, many people find marine parts a burden on their wallets, and attempt to find value or savings on their purchases, and this is what drives them into the auto parts direction.

Heck I am guilty as well, but I can not see how anyone without some reasonable experience in boat engines and systems as well as auto related as well could be able to make inteligent decisions.

I can see how it would be easy to get trapped into "a part is a part" etc, and have had inexperienced parts people try to talk me into trouble in an attempt to sell, or even to help.

As some have pointed out already there are areas that are more sensitive than others, and I totally agree with this. From my own experience and testing there are some areas where with a little work and common sense you can save a few $$.

I remember one time in the past where I needed to get a water pump swapped out for a trip the following day, and there were not any marine units available local. I understand that the auto unit I swapped in with the SS back plate borrowed from the old marine unit was running fine when the engine was removed for a repower.

Would I recomend this with a starter or alt etc? Not unless the installer knew how to properly install the shields or screens into the auto pieces.

Its scary business, and the idea of convincing people to spend a few extra $$ for the marine parts and the safety that comes with them seems to be a good one even if some of the prices being charged for marinized auto parts are little less than criminal."
 
"Lenny, you have a sound appro

"Lenny, you have a sound approach to this issue. A Person has to be real experienced on boat engines before he can decide what parts can be substituted in a boat motor. I'm rebuilding a merc 260. A good example of what you are saying is I chose an RV type cam instead of the stock Merc cam. The specs are very close and I saved a few $$$. I doubt anyone here will be able to tell the difference when in my boat.
BUT, you really have to be smart about it!! I believe any advice on this subject in a public forum such as this is "stick to MARINE parts"
As far as being a "burden on their wallet" excuse, I don't buy it. If you can't afford to boat properly and safely, don't boat at all. Besides, you don't always have to spend a ton of money. The Internet has some GREAT deals on marine parts. Also, some good used parts are on Craiglist and Ebay or your local marine salvage yard. Just adding my opinion.
Chris"
 
"Chris

Thanks for the kind

"Chris

Thanks for the kind words!!

Interesting you bring up the cam issue as this is one I may have to tackle myself on my Merc 7.4.

In preperation I tried to ID the specs on the marine cam used by Merc so I could match them up and maybe even improve on it during my selection just in case I end up needing to change it.

Well low and behold those specs are not readilly available, and the way to decide on a proper profile or grind seems to be limited to being from experience and knowledge on valvetrain and how it relates to power (hp torque and rpm range etc) and what would work best for your specific engine and use.

Sure you can trust someone in the industry or just try and locate an OEM part, but that is very limiting, and your at the mercy of person who makes the recomendation.

I have learned from experience (both boat and non marine related) that the people at the dealer are not as experienced as we would like, and its especially true when you step outside of std oem stuff and are looking for performance or mileage gains etc.

My issue with this is that though I have areas where I have put in my time, and fully understand every working area of the engine and systems (right down to comparing and testing changes in lift and duration etc to that of flow and velocity, and how it effects torque and hp curves) but these engines are not marine related, and I honestly do not want to have to become an expert marine engine builder just to maintain my boat.

This is why our forum here is so valuable, and the information some of you guys offer is more than enough to get someone with basic mechanical/engine knowledge the info they need to make inteligent decisions.

Also something I mentioned above about "trusting" someone in the industry is not as simple as it sounds. I wont get too much into it as it would be great as a thread of its own, but basically not everyone in the business is honest, knowledgable, and trust worthy and therefore many boaters have had poor experiences with marine mechanics and yards.

Then again those expensive, incompetent, and questionable repairers are what drives so many people to do their own repairs and maint, and also makes this forum so popular and important!!

Thank You All!!"
 
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