1977 Thompson Mercruiser 470 - identity please

nhhockeyplayer

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Hi Folks,

I am trying top identify what I got here... I been had... again.

I was sold a boat who claimed it had 400 hours on the engine and it ran. I trusted them only to find after fixing coil ignition and fuel systems that the 3rd cylinder is only outputting 35 psi's

And the out drive appears to have been hacked by a beginner.

So I am going to give this another round of fixing.

Can someone identity for me what this beast really is ? I thought it was a gm engine and I dont know what alpha is or M or MR or R of Bravo.

All I know is I got to repair the power trim lines and pins/bushings and see about what this cylinder is up to.

Any tips on what to do with the engine and cylinder is appreciated.

I fell in love with this thing but it isnt returning on me.

this site wont allow me to attach an image

: (
 
here are the photos

the out drive says mercruiser 470
 

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CAN SOMEONE ADVISE ME AS HOW TO ATTACK THIS BLOWN CYLINDER ?

I wonder about how it got that way... its a car engine and has antifreeze... wouldnt this hold up over winter ? I am a newbie on boats.

Ok if water freezing was the causing issue what could it affect and why the third cylinder if any cylinder ?

Do I start tearing this thing apart from the top down ? From inside the boat ?

I dont have any lift of any kind.

Wondering what I might find. It made some god awful godzilla sounds when last attempt to turn over... it did make one last cough with flames coming from carb. I am hoping for a miracle and that it might not be blown and my read on the cylinder was in error. i got a crappy compression checker.

thanks for any help

just trying to give a boating summer to my poor legally kidnapped baby girl who is 11

Anyone who wants to leave a large bag of money on my front door please remit... it will go to a good cause of demolished kids ...mine in USA
 

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I paid $1200

he rooked me... told me everything he could possibly told me and it all came to light after the fact... it was all lies.

He claimed he had 8 boats too and ocldnt give ma a break... even lied saying he wold refund me... he didnt... and his < removed > sister too helped him sustain the sale...

no help in NH

ANyway, I am trying to find out hwo to read the symptoms. The oil is really BLACK. I changed it but it remains evil BLACK.

I will redo my compression check when I install new batteries.

I am praying it might be a head gasket.

But I am also praying it isnt a frozen water expansion low end top end crack somewhere from wate4r freezing.

I woudl like to fix it.
 
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my complaint about these mercruisers is the "power trim"

what a dumb name
and worst place of anything... wires submerged in water ? Heellooooo..... did anyone think that might have a quantum effect on the structure of the material? Oh yeah they might last forever... dont think so... the owner will have to rip the back end apart and replace them only every 3 years.
One would think... why not a backup design... like MECHANICAL. ???

no they had to ruin the whole design with this stupid feature. and clog up the whole back side of the boat with fifty different wires going all over the place like spaghetti.

I see too many boats for sale with these dumb wires just torn right out.

and I see a bad design overall with ALL boats.

its only for rich people who have money to burn and the DESIGN was just to burn more money.

so I am sittin here with a masters degree in high tech U.S. ARMY and watching INDIA children blow doors on our kids by happiness alone and their moms and dads both work as software engineers (yea we gave them our industry) while they got five different job oiffers in their back pockets.

Lookin atboat designs in general I see the light.

All we do is screw ourselves to no end and I would never want to be a kid here in USA... we cant even go on a damn boat ride... we have to worry about the loser up the road (and he was my neighbor <removed other person's personal information>) taking our last dollar for a broken boat that induced a new foreclosure.

Have I violated any posting ethics? sorry

I say the boat design stinks and is all dumb. The stern drive. It could have been done better. Mechanically.

And we say we are the biggest and the best ?

I have lost all respect for this place and the people for what they have become.
 
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its not the dollar

its the principle... see the forsale sign

thats what we have become

but coming from a guy who is forced to heat his house with his kitchen oven... yeah I am off my rocker

just make sure you keep your kids and family out of NH

its not the place if you want to make in USA
 

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Burt you might want to consider the dollars already put into it... and hours?

at $90 per hour mechanic rate it topples $10,000 already

I REFUSE TO DO THIS TO SOMEONE ELSE...and I wont..including all of the other things that the people of NH have done to us here.
 
Awwww...... sounds like the world in general is not conforming to your expectations. There are only two ways to address this problem, adjust your own expectations, or go about the onerous task of changing the world. As a wise man once said, in the contest of you against the world, back the world ! :D
 
Well I shouldn't come off too bitter...
at least we dont have to worry about fitting thru the eye of a needle.

:P
 
I'm sure it was a long depressing winter up there, the sun will shine again soon ! :cool:
 
Welcome to the forum, and very sorry that your experience with this boat has been frustrating; however it's probably time at this point before the thread spirals off topic entirely to insert a request to please keep the topic more technical. The forums here are meant to be a place to ask technical questions and get (technological/design) advice. The forums here are not meant to be a venue to air grievances against other people or a whole state or country, etc. so let's please try and focus the topic on the technical questions and please direct the personal stuff to facebook or another site. Thanks very much for your understanding.
 
The 470 was an engine custom made by Merc, it has a big block Ford ( 428) cylinder head and same size Ford engine bore.
They came factory filled with coolant so they usually are immaculately clean on the inside.
You need a very large battery to crank them with being that they are a huge 4 cylinder which is close to the hardest design to crank.

The drive has later housings than the original so could either be just a 1 drive or the lower might have the alpha internals but the old style housing look. You will need to separate the 2 to see what the driveshaft looks like to determine that. Either way its no issue that engine couldn't break the original drive. All the drive upgrades were made to allow the the drive to survive with a V8.
 
thanks guys for all the good feedback.
and I apologize to moderator for slidin off topic. its a new day a new start.
i like this boat. its fun sittin in the sunshine working on it.

not sure what will tell me if the low end internal is alpha or pre-alpha

i will tear it down though

i still need a read on whether its a head gasket.,.. water in the oil ? or oil in the coolant ? compression loss ? oil or water or both in the cylinder ?

and I will check for snapped piston if such a thing can happen

folks have told me these boat engines cannot cool right and they rot from the inside out... maybe its disentegrated?

peace
 
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