help needed to bringing a 470 Mercruiser, Alpha 1 back to life

[Striker89]

Hello All,

Firstly im well aware of all the problems and dislikes towards the 470 mercruiser,
im working on getting my fathers boat up and running and useable for the summer and possibly put on the market.
The boat has laid dorment in excess of 7 years,

im looking for some guidance and information on how to go about this,
Once replacing all fluids and batteries, draining fuel etc, cranking over without spark plugs, is it safe to try and start and let run it up?

following this, replace all hoses and fuel lines, flush cooling system, ,replace water pump and impellor, bellows, inspect heat exchamger and elbow.

if i have missed anything or parts please let me know.

cheers,
Jeremy

 

[Scott Danforth]

welcome aboard

first and foremost, I would not simply crank it up especially if it has been sitting that long. even if it starts, you run the risk of sending impeller pieces into your motor and sucking all the crud in the fuel tank into your carb

first, drain the cooling system, pressure test and make sure you do not have a leak, specifically at the cam bearing, manifold, head gasket or heat exchanger
do an oil change and make sure you prime the oil system. this will require pulling the distributor and using an oil priming tool
re-install the dizzy and set timing
drain the fuel tank (you will get to cleaning it later)
remove the carburetor and clean it (requires disassembly, a carb kit, etc)
using a small outboard gas tank with fresh fuel, plumb the fuel pump to the gas tank
clean all battery cable connections
remove the outdrive. then simply use duct tape to secure the end of the garden hose in the water passage on the gimbal housing

now you can fire the motor up

back to the outdrive. with the drive still off:
check alignment
check gimbal bearing
replace bellows
replace raw water pump
change gear lube
perform an anode maintenance

reinstall drive

clean the insides of the fuel tank (use the search function, plenty of methods to clean the fuel tank)

inspect the anti-siphon valve.

now you can re-connect the main fuel tank

 

[stonyloam]

Yeah Scott has it pretty much covered, I would add that once you get it running, do a compression check to evaluate the head gasket health. Best way to check for the cam seals leaking is to look for antifreeze leaking out of the small weep hole in the engine waterpump while it is running and up to operating temperature. Don?t know if you mentioned it, but change the points too.

 

[QBhoy]

As mentioned and if you insist in persevering with this jinx of an engine...check the water pump seal and seating surface for wear. Most will have a groove worn tjere and makes it difficicult for all the countless seals you will have to replace every other time you use it.
Also make sure your phone is fully charged for when it breaks and need a tow home....haha. Cruel, but accurate

 

[stonyloam]

I have owned mine since ?91? and NEVER been towed. If your compression is good and you keep it cool by replacing the impeller every two years it will be just fine. Read all of the ? how do I winterize? posts here then go out and pull the aft plug on the underside of the exchanger (takes about two minutes) and you are done. Then in the spring you can read all of the ? milkshake oil ? posts and say to yourself ? maybe that ol 470 ain?t so bad?

 

[QBhoy]

I have owned mine since “91” and NEVER been towed. If your compression is good and you keep it cool by replacing the impeller every two years it will be just fine. Read all of the “ how do I winterize” posts here then go out and pull the aft plug on the underside of the exchanger (takes about two minutes) and you are done. Then in the spring you can read all of the “ milkshake oil “ posts and say to yourself “ maybe that ol 470 ain’t so bad”

Stoneyloam, I'm convinced you actually have a 4.3 with a 470 decal....haha.
Seriously though, fair play to you for keeping that engine in good health. You deserve a medal or some sort of recognition.

 

[stonyloam]

Thanks Q! Yeah you need to be on top of a 470 all the time. Keep an eye on the coolant level (check EVERY TIME you go out), track down any loss, watch for leaks, check the compression, and look for white ? steam cleaned? plugs. And never ever let it overheat. Mark your temperature gauge at normal operating temperature and if it ever creeps up at ANY rpm, find out why. They do not like to be neglected! All lessons learned the hard way

 

[Benny67]

As mentioned and if you insist in persevering with this jinx of an engine...check the water pump seal and seating surface for wear. Most will have a groove worn tjere and makes it difficicult for all the countless seals you will have to replace every other time you use it.
Also make sure your phone is fully charged for when it breaks and need a tow home....haha. Cruel, but accurate

What's up with you?

If this engine was as bad as you say why did Mercuiser make 10's of thousands of them..maybe more ?

The real issue with these engines is poor maintenance and lack of understanding from the owners....and that's due to the fact that there are so many of them out there and that the majority of boat owners are novices when it comes to mechanics and relate a boat to their automobile thinking that they can just turn the key and go and then when it breaks they call it a "piece of s**t cause it broke

Bottom line, it has it's deficiencies but there are way many other designs out there that are just as bad or worse.

Qboy,

I would think your experience with these engines may be due to the fact you are socializing with people who have little to no mechanical skills.

I say that due to the fact it seems you have never owned one..or at least that's what I have gathered from your previous posts.

 

[Scott Danforth]

Benny67 Mercruiser abandoned the 470 due to high warranty costs and high production costs (it cost them more to make than it did to buy a V8 from GM because of the required heat exchanger). the manufacturing volume isnt as high as you think. from a design standpoint the motor has way too many known design flaws against it, primary three being an iron head on an aluminum block, the open deck (floating bores), and the non-hardened camshaft. the two good things are the alloy block and the heat exchanger. as far as worse designs, Mercruiser came out with the Vaser too (much worse than the 470). OMC and Volvo also have their edsels as well as their tuckers

As stonyloam can attest, constant attention is required with these motors. one little hickup of a leaf or plastic bag getting stuck on the intake grate of the water inlet and the temp spikes more than 10 degrees.....the floating bores will spit the head gasket faster than you can imagine.

the design flaws on the motor are well documented. However the OP Striker89 simply wanted to know what he needed to do to resurrect his fathers boat and stated he is aware of the issues. Since he hasnt returned, this may be a dead thread

 

[salty3rd]

I maintained and used a boat with twin 470's for 12 years. I learned the hard way how to take care of them. This past season I bumped up to a boat with twin 305's and I don't miss the 470's one bit. If I were to give advice to a potential 470 owner I would tell them if you want to enjoy your boat instead of constantly tweaking or fixxing it than the 470 probably isn't a good choice.

 

[Benny67]

Benny67 Mercruiser abandoned the 470 due to high warranty costs and high production costs (it cost them more to make than it did to buy a V8 from GM because of the required heat exchanger).

Huh?

You can't put the 470 and V8 in the same category. Two totally different types of powerplants.

The GM small block is a no brainer as far as a effective, reliable and cost effective powerplant...For christ sake it's been pushing automobiles around since 1955.

You simply cannot use a small block in every application you could a 470. And vice versa..

Like I said in the past, it has it's weaknesses, I'm not doubting that. My argument is this plain and simple, maintain the engine and it will be effective and reliable.

I can understand the frustration of a lot people that do not have the skill set to properly understand what is required to keep the motor working effectively and reliably. To most of the masses, It's just easier to call the engine "junk" and move on.

However, like I also said, it's usually the people with the lack of true mechanical skills that are so dead set against it.

We could go at it all day but you have your mind made up about it. Good luck to you.

 

[QBhoy]

What's up with you?

If this engine was as bad as you say why did Mercuiser make 10's of thousands of them..maybe more ?

The real issue with these engines is poor maintenance and lack of understanding from the owners....and that's due to the fact that there are so many of them out there and that the majority of boat owners are novices when it comes to mechanics and relate a boat to their automobile thinking that they can just turn the key and go and then when it breaks they call it a "piece of s**t cause it broke

Bottom line, it has it's deficiencies but there are way many other designs out there that are just as bad or worse.

Qboy,

I would think your experience with these engines may be due to the fact you are socializing with people who have little to no mechanical skills.

I say that due to the fact it seems you have never owned one..or at least that's what I have gathered from your previous posts.

What's up with you?

If this engine was as bad as you say why did Mercuiser make 10's of thousands of them..maybe more ?

The real issue with these engines is poor maintenance and lack of understanding from the owners....and that's due to the fact that there are so many of them out there and that the majority of boat owners are novices when it comes to mechanics and relate a boat

I have never owned one. Towed a few home though My closest friend had one, then another and another. Before he replaced with a 3.0.
As for Mercruiser and the production of these engines. In comparison to the other engines, the 470 reign was a drop in the ocean. They were discontinued because of their reliability....or lack of it.
Honestly, I admire you guys who have the time to keep them running, honestly I do. I'd most likely be the same if I had one and the time to spend fixing and maintaining g them. Just that most people want turn key reliability and as mentioned, this engine has ruined many great days out in the water for us and out friends. Something not soon forgotten.
I am all for maintenance and best practice, but when you are dealing with a piece of machinery with an inherent and recognised fault, it's harder than it should be.
I was astounded by the power and punch of these engines, being fair....but like I say. Unless the boat owner has the know how, time and patience for these engines, I couldn't recommend them. Could you ?
A scenario for you...
Two identical boats are for sale, same age, condition and price. Only that one has a 4.3 175hp and the other has a 470 160/170hp.
The potential buyer has no mechanical knowledge, has a full time job and just want to use the boat reliably on the weekend with only the usual annual maintenance.
Are you telling me you would honestly recommend the 470 over the 4.3 ?
Tell the truth now !

 

[stonyloam]

Yeah, I would recommend a 4.3 over a 470 any day, except today when I hauled it out for the winter. Took my brother in law less than 3 minutes to winterize it, right on the ramp

 

[nola mike]

I've had mine for 9 seasons now. Rowed home once, blown outdrive when I first got it. On water fix once when a wire rubbed through. Alternator fix after year 6. Still on original cam seals. No blown head gaskets. 31 year old engine. Only (maybe) 470 specific failure was bent valve after exhaust gasket leaked into #4 over the winter (ok, I did the head gasket then, and with an automotive gasket). Many other repairs/maintenance that go with an old engine in the salt. My buddy's MPI 305 has left him stranded once this season and we had to take mine out last weekend because his won't start (gonna be fun to diagnose that black box computer system). Going to throw it in for a ride now.

 

[ondarvr]

I've had mine for 9 seasons now. Rowed home once, blown outdrive when I first got it. On water fix once when a wire rubbed through. Alternator fix after year 6. Still on original cam seals. No blown head gaskets. 31 year old engine. Only (maybe) 470 specific failure was bent valve after exhaust gasket leaked into #4 over the winter (ok, I did the head gasket then, and with an automotive gasket). Many other repairs/maintenance that go with an old engine in the salt. My buddy's MPI 305 has left him stranded once this season and we had to take mine out last weekend because his won't start (gonna be fun to diagnose that black box computer system). Going to throw it in for a ride now.

So one of them did work as designed, nice to know not all of them failed.

 

[nola mike]

Yeah, I would recommend a 4.3 over a 470 any day, except today when I hauled it out for the winter. Took my brother in law less than 3 minutes to winterize it, right on the ramp

Your brother in law must not be mechanically inclined if it took him 3 minutes. Maybe that included finding the wrench?

 

[stonyloam]

Your brother in law must not be mechanically inclined if it took him 3 minutes. Maybe that included finding the wrench?

Always the critic Mike . On our boat we need to pull the ?doghouse? and put it back and that that takes a little over a minute, and another 15 seconds to pull the transom drain plug, reach in, pull the plug and drop it in the cup holder, about about a minute and a half, and yeah I had to hand him the wrench. All in, about 3 min. start to done for the year

 

[achris]

the design flaws on the motor are well documented. However the OP Striker89 simply wanted to know what he needed to do to resurrect his fathers boat and stated he is aware of the issues. Since he hasnt returned, this may be a dead thread

Quite right Scott. Jeremy (and his father) are very good friends of mine. I directed him here as I'm away and can't help him. He just needs some pointers to get the engine going and to be able to use it for a while. We have no need of winterizing in Australia so that side of it is not a concern. When that engine was going, it was one of the smoothest 470's I had ever heard.

Unlikely a 'dead thread', Jeremys' work also takes him out of circulation for days at a time.

Other things all of you 470 haters need to consider. In Australia we have no cars with GM 4.3 litre engines. Just 'swap it out for a 4.3' is not an option we have. People in this country with 470s are pretty much stuck with them, or facing a $eriously expensive update (more than $15,000). And in some cases that isn't even possible. The engine box for a 4.3 is considerably wider than that of a 470. Some boats will not accommodate that...

So when someone asks for advise with their 470, the very last thing they want to be told is to swap it for a 4.3.... So please stop doing that!

Chris. ...

 

[Scott Danforth]

Chris, you probably already know

changing the head to an alloy edelbrock Ford FE head (429/460) helps with the thermal expansion issue. a laser-welded 6mm bore girdle, tig welded in place to stabilize the bores helps the floating bore issue.

two mods that are definitely worth it if the motor needs to come out and the head needs to come off.

 

[Benny67]

What's up with you?

Man, I'm just not into the negativity...it's a pet peeve of mine.

Like my mother said, you got nothin nice to say..well, everyone knows the end.

That's what's up with me.