another MT trihull (engine help please)

[Ab5851]

hey all im new to site but not totaly new to boats, i have just purchased a mark twain 1973 16' trihull w/140merc cruiser

now this is wher i hope yall can help i bought it from a man that was over seas for a couple of years and come home to this boat that whould not start so he put it on CL and i bought it for CHEAP

after pulling the plugs they wher all rusted up(i mean soild!!) he said the boat run fine when he put it on the trailer the last time and had the hitch keys with him in iraq so he knows the boat hasnt been out

i also tried to turn the engine over with a bar and it didnt move a bit so i figure the rings are rusted to the cyl. walls

i have been searching all afternoon with the engine ser #3509854

ther is no othe tags on the motor ecept that one and the "merc cruiser 140" tag on the vavle cover,

can yall help to tell me what this engine is?
has anyone had this rust problem before?
do i have to pull this thing apart?

oh ther was no water in oil?

thanks in advance , dusty

 

[Bondo]

Re: another MT trihull

Re: another MT trihull

can yall help to tell me what this engine is?
has anyone had this rust problem before?
do i have to pull this thing apart?

Ayuh,... It's the 3.0l Chevy motor...

If it's Rusted, it otta be torn down, cleaned up,+ rebuilt...

 

[Ab5851]

Re: another MT trihull

Re: another MT trihull

thanks!!

wher is a good place to get parts or can i get them at any local parts store?

also any ideas how it got all that water in ther and how do i keep this from happening to me after rebuild?

thanks, dusty

 

[Don S]

Re: another MT trihull

Re: another MT trihull

Depends on what parts you need and are looking for. First thing you have to do is take it apart and and see what parts you actually need, or if you need an engine instead.

 

[Ab5851]

Re: another MT trihull

Re: another MT trihull

well i figure i whould just rebuild it from top to bottom that way i know what i have when it was done, im a mechanic by trade so this dont seem like much of a job and i found a basic rebuild kit localy @ NAPA for about $300. that includes all gaskets,seals,bearings,rings,wrist pins, head set, plus a few other misc. marine gaskets.

the gaskets are all felpro and clevite bearings i was just wanting to know if ther was a better line out ther being as this is my first marine engine also if that was a good buy or am i over paying?

as far as wher the water came in at i dont have a clue and was hoping one of you could tell me what i need to look for besides the head maybe cracked

the boat was bought in phoenix AZ and has been ther its whole life till i brought it home so i know it hasnt frozen and broke anything that way. thanks for the help from all

 

[Bondo]

Re: another MT trihull

Re: another MT trihull

Ayuh,... Fel-pro,+ Clevite are quality parts,...

The water may have run down through the carb, or there may be a cracked casting...
Close Inspection during tear down will hopefully answer that question...

 

[Ab5851]

Re: another MT trihull (engine help please)

hopefully it was just water threw carb.... gonna tear it down fri and see

thanks!!

 

[Ab5851]

Re: another MT trihull (engine help please)

im gonna order parts for this thing in the morning i know you guys said its a 3.0 but is the bore size the same? may seem like a stupid question but it aint making sense to me that a 140 (which mine is) and a 120 are the same 3.0cu. in. or am i missing somthing?????

also i have done searches all week on a good site find a rebuild ie. pics and such and have had no luck.

is ther any on line site that anyone knows of or am i gonna have to buy a manual

thanks in advance
dusty

 

[Ab5851]

Re: another MT trihull (engine help please)

ok guy i pulled the head and found the cyl full of water and rust now i know im going to rebuild it but how did the water get in ther?

i inspected the manifold and the elbow and didnt find any cracks but couldnt really see inside of them either.

the intake ports on the head were full of rust also but the exhaust was clean.
also the head mating surface was clean and did not look to have any cracks.

so i figure its got to be somthing with the manifold.......right?

is ther any gaskaets or somthing like that that could of led to this or am i going to have to buy a manifold?

thanks for the help

dusty

 

[Ab5851]

Re: another MT trihull (engine help please)

well i guess this forum aint what its cracked up to be i am a member of many off road forums and crawler builder forums and always try to help a newby thats trying to start out (ya know a family atmophere) but i guess it dont work like that in the boating world . not on this site anyway. all i have got is a bunch of bland ansewers . oh well take it easy to all

 

[woosterken]

Re: another MT trihull (engine help please)

hey at the top of this forum is a sticky note titled "adults only"
in there you will find down loadable merc. manuals

woosterken

 

[fuzzybob]

Re: another MT trihull (engine help please)

Dusty, welcome to iboats.

I'm NOT a mechanic by trade so probably not qualified to answer your ?'s but I can tell you to go to the top of this forum page click on the "Adults Only" sticky. There you can find a gold mine of boating info, related to care and maintenance. You will also find the OEM manuals for your engine and outdrive. You can download them for free.

Don't give up on the forum just yet. It's a great forum with tons of expert advice. Sometimes a post will kind of slip through cracks like yours did.

Welcome and good luck on your project.

 

[Bondo]

Re: another MT trihull (engine help please)

well i guess this forum aint what its cracked up to be i am a member of many off road forums and crawler builder forums and always try to help a newby thats trying to start out (ya know a family atmophere) but i guess it dont work like that in the boating world . not on this site anyway. all i have got is a bunch of bland ansewers . oh well take it easy to all

Ayuh,... Sorry you aren't getting the replies your lookin' for....

I answered your Questions once...
Just because you ask the same question, reworded don't change the Answer...
"The water may have run down through the carb, or there may be a cracked casting..."
Follow the rust trails to see where the water came from....

And, of course,...
This is a Forum, not a chat room...
I can't/ won't answer every single post, nor will anybody else...
Also, it's up to You to build Interest with your title,...
Naming the hull in a Motor forum probably ain't the best start...
After that, it's the Luck of the draw....
If you're lookin' for somebody to hold your hand,...
I guess your Right,... This Ain't the forum for You,... We're all Big boys here....
If you want Help,.... It's Here....

Oh,... 1 last thing,... Many of Us just won't/ don't bother pecking out an amswer than can Easily be found if the poster puts in just a tiny bit of effort, by Readin'...
I'll make an exception,...

im gonna order parts for this thing in the morning i know you guys said its a 3.0 but is the bore size the same? may seem like a stupid question but it aint making sense to me that a 140 (which mine is) and a 120 are the same 3.0cu. in. or am i missing somthing?????

As was Already said,... Don't buy parts til it's torn down, inspected,+ meassured.....
The 2.5l, 120hp is 1 motor,+ the 3.0l, 140hp is Another motor,...Sisters, Not twins...

 

[haulnazz15]

Re: another MT trihull (engine help please)

I would also guess that there was water that came down into the carb or through a leak somewhere if it only showed rust on the intake sides.