Camshaft movement

[achris]

... however the spark plugs were white and "looked clean". ....

Running lean, and overloaded....

 

[Searay205]

So with a carburetor how do you set the mixture screw? He has a Mercarb so there is only one. You adjust to highest idle than adjust idle screw. Similar to using a vacuum gauge and adjusting to highest vacuum. One little screw all he has to adjust fuel mixture.

Also strange he used same prop for years and it rears its ugly head now.

Is it possible his timing is off causing all these issues? I just see how he will mitigate in future, small prop definitely won't hurt.

 

[achris]

So with a carburetor how do you set the mixture screw? He has a Mercarb so there is only one. You adjust to highest idle than adjust idle screw. Similar to using a vacuum gauge and adjusting to highest vacuum. One little screw all he has to adjust fuel mixture.

Also strange he used same prop for years and it rears its ugly head now.

Is it possible his timing is off causing all these issues? I just see how he will mitigate in future, small prop definitely won't hurt.

Mixture screw only affects the idle and 'off idle' throttle positions. Once into 'mid range' the idle screw doesn't have any influence on fuel mixture.

And yes, engines can survive for quite a while being overload, and run lean, but eventually they will go bang. All it requires is a very small variation for it to go 'over the edge'. Like an extra person on board, or a bit hotter day...

Chris....

 

[TMcDaniel]

I'm going to get the rebuild kit tomorrow from my local mercruiser shop. Should I look into getting a different carb setup or just do the rebuild?

 

[Scott06]

I'm going to get the rebuild kit tomorrow from my local mercruiser shop. Should I look into getting a different carb setup or just do the rebuild?

Just properly rebuild what’s there. No need to waste money on a new carb unless inside is corroded from fuel contamination.

dump your fuel filter into a glass jar or freezer bag, should be nothing but clean clear gas. If otherwise clean out fuel tank and fuel system

 

[alldodge]

Agree just rebuild
What is the number tagged on the carb?

 

[TMcDaniel]

807764n
18 9z11

 

[alldodge]

Yes, that is a Merc 2bbl, full part number 3310-807764A1
So unless someone changed the metering jets it should be the right carb

Main jet 811835
Power jet 9435 (0.74mm)

https://www.mercruiserparts.com/bam/subassembly/31490/9021/80

 

[TMcDaniel]

How do I upload a short video or sound file?

 

[alldodge]

Upload to youtube and link here

 

[TMcDaniel]

Here is a video with the knocking im hearing.

https://youtu.be/zTuL1Eu3dA4

 

[alldodge]

That's rod bearings and the motor is toast

 

[TMcDaniel]

They have less than 30 minutes on them...

 

[TMcDaniel]

Will a new crank and bearings fix it or should i spend the $1500 (which I don't have) for the short block.

 

[Bondo]

Ayuh,..... I recommend ya short block it,..... for reliability,......

 

[alldodge]

I do know what your going thru, been there many years ago when just having 2 nickels to rub together was an issue

You don't need a short block but you do need to have the crank, rods and bearings sized to fit. The issue is going low cost, which has come to bite ya again. Don't know what a local shop will cost to do the work, but do some checking

Might have better luck with cost if you can find a rotted out hull with a good motor. Strip the boat and junk it

 

[TMcDaniel]

2 shops said it would be faster and just as "cheap" (I use the word cheap lightly) To get a short block, one shop is buisy for 4 weeks and the other 6. And I dont want a used motor cause I dont want to be dealing with my current issue next year. So I guess my son wont be eating for the next few weeks...

one other question, I rebuilt my carb but how will I know it's not running lean again? And any suggestions on where I should get the short block from? I've been looking online, some places have them cheap but after I get all the add ons they still come up to $$$$. If I'm going to starve my son I want it to be worth it

 

[achris]

..., one shop is busy for 4 weeks and the other 6. ...

Yep, it's called the boating season. It's normal. When I had my shop, during summer we were booked up for 3 months at times. Good shops will be... If you find a shop that can do it 'now', run! There's a reason they aren't busy!

... And any suggestions on where I should get the short block from? I've been looking online, some places have them cheap but after I get all the add ons they still come up to $$$$. ...

http://centerstateengine.homestead.com/remanengines.html
http://marineengines4less.com/marin...-marine-base-engine-replaces-years-1996-2007/

Chris......

 

[alldodge]

I'm finding fleybay and after shipping its over 1000
Rapido Marine does short and for 150 more it comes with heads.

Most here have bought from Michigan Motorz and had good experience but they are higher. I don't have a good place to recommend currently

 

[TMcDaniel]

So I've decided to with the long block from marine engines 4 less. It's only $400 more and by the time I buy a new timing cover a new gasket set and the other parts and pieces I think it's worth the extra cash. I hope my son gets a job soon cause hes going to be hungry for a while.

thanks to everyone who has helped me through my nightmare. I appreciate all of the advice.