Where should I spray seafoam on an MPI engine??

JP_R

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Hello Guys,

Long story short.... I parked the boat at my house and did not start it for like 3 months. I tried firing it up last weekend and after several tries it fired up but like 10 seconds max. I then kept trying until the starter just gave up. The starter sounds like it is spinning but not engaging (broken bendix/fries selenoid??) the ring gear/flywheel.

I am replacing the starter on wednesday (hoping it is the starter that is damaged) but I would also like to treat the engine with seafoam for hopefully a better start.

Now to the question. If I were to use the seafoam, can anybody point out were should I spray it or pour the liquid in? keep in mind my engine if fuel injected. Can anybody send a picture of the vaccum line I should pour it in??

Thanks in advance
JP
 

Don S

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Re: Where should I spray seafoam on an MPI engine??

Seafoam for what? DO NOT spay anything in the intake of an MPI engine. Not even fogging oil.
 

bruceb58

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Re: Where should I spray seafoam on an MPI engine??

What would you want to use SeaFoam in the first place?
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

What would you want to use SeaFoam in the first place?

well from the advertising I just saw about seafoam, it said it would help on starting engines that have been sitting for a while.

I guess I need a mercruiser knowledged person that can help me out figuring my problem.

any advise on what I should so to try to fire up the engine quick after I install the new starter?? I already changed the spark plugs, new oil, I dont know how to check the timing..
 

robert graham

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Re: Where should I spray seafoam on an MPI engine??

Spray some WD-40 or penetrating oil on that bendix gear on top of your starter before you replace it$$ Also check all battery cables/starter cable connections, etc. before you replace starter$$. You could spray some Seafoam into air intake after you get motor running. Probably need to check your entire fuel delivery system from tank to motor, may have some stale fuel problems. Good Luck!
 

Don S

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Re: Where should I spray seafoam on an MPI engine??

You could spray some Seafoam into air intake after you get motor running.
NO, it will never get to the engine. As I said earlier, DO NOT spray anything into the intake of a MPI engine, not even fogging oil.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

Spray some WD-40 or penetrating oil on that bendix gear on top of your starter before you replace it$$ Also check all battery cables/starter cable connections, etc. before you replace starter$$. You could spray some Seafoam into air intake after you get motor running. Probably need to check your entire fuel delivery system from tank to motor, may have some stale fuel problems. Good Luck!

DB electrical already shipped the new starter. I am so mad as the starter that went bad was practically new. I replaced it 6 months ago and used it 3 times. I think the selenoid fryed.

Before even installing the new starter I am going to test the old one bypassing the selenoid and see if it works. It is my fault because I held the ignition for too long trying to get engine to finally start.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

NO, it will never get to the engine. As I said earlier, DO NOT spray anything into the intake of a MPI engine, not even fogging oil.

Don, any suggestion as to what should I do to get the engine started?? I am tight on cash right now and would like to maybe fix this by myself.
 

Don S

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Re: Where should I spray seafoam on an MPI engine??

I guess I need a mercruiser knowledged person that can help me out figuring my problem.

First off, we need a SN for the engine to figure out which MPI system you have.
The SN is located just above the starter on a metal tag.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

First off, we need a SN for the engine to figure out which MPI system you have.
The SN is located just above the starter on a metal tag.

I dont have the exact serial number right now as I am at work but the range is between 0W060000 THRU 0W309999. If it helps, it is a 5.0 MPI with alpha one
 

Gary H NC

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Re: Where should I spray seafoam on an MPI engine??

Never crank an engine for more than 5 to 8 seconds or you will keep buying starters.They need time to cool off.
You need to find the problem.Fuel or ignition related.
Is it getting spark? Is it getting fuel? Throwing parts at it can get really expensive.
SeaFoam is not a magic fix for a hard starting engine.
 

robjen1019

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Re: Where should I spray seafoam on an MPI engine??

Make sure the tank is full of gas. I completely tore apart my volvo last summer chasing down a low fuel tank. Felt pretty stupid.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

Never crank an engine for more than 5 to 8 seconds or you will keep buying starters.They need time to cool off.

well I guess I learned the hard way. I've got the new one on the way and I will make sure I do not cranck the engine for more that 8 seconds.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

Make sure the tank is full of gas. I completely tore apart my volvo last summer chasing down a low fuel tank. Felt pretty stupid.

Tank is full!! I filled it up last time I used it. what I did forget was to put some stabil to it.
 

Don S

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Re: Where should I spray seafoam on an MPI engine??

The first thing you need to do is head up to the Adults only sticky and download the manuals for your engine.
#31 for the engine, #36 for the ECM.
Before you try to start it again, might want to read this service bullein on priming the fuel system.

http://www.boatfix.com/merc/Bullet/01/01_04.pdf
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

The first thing you need to do is head up to the Adults only sticky and download the manuals for your engine.
#31 for the engine, #36 for the ECM.
Before you try to start it again, might want to read this service bullein on priming the fuel system.

http://www.boatfix.com/merc/Bullet/01/01_04.pdf

Oh man I sure did not know that. Thanks for that service bulletin Don.

I already have the service manual but I am not suuuuper experienced. Don't get me wrong I do as much as I can but some things I just do not have a clue, for example adjusting timing!!!.
 

Don S

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Re: Where should I spray seafoam on an MPI engine??

I already have the service manual but I am not suuuuper experienced. Don't get me wrong I do as much as I can but some things I just do not have a clue, for example adjusting timing!!!.

Timing is easy on that engine, it's NOT adjustable, the ECM does it all, and don't even think about turning the distributor, or you WILL have a problem.
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

Timing is easy on that engine, it's NOT adjustable, the ECM does it all, and don't even think about turning the distributor, or you WILL have a problem.

Oh ok. good to know. For now I am going to try to get the boat running. After that, I will call a mechanic for a final tuneup. I would like the boat to be turn key. When I first got it, I would turn on Ok but not after maybe 5 seconds of crancking.
 

mkast

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Re: Where should I spray seafoam on an MPI engine??

I guess I need a mercruiser knowledged person that can help me out figuring my problem.

Have you looked in the Mercruiser maintenance manual in the troubleshooting section?
 

JP_R

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Re: Where should I spray seafoam on an MPI engine??

Gentlemen,

I just read something on another thread that might contribute to the problem I am having. To explain further..... one day I was working on the boat changing the oil sender unit (because needle in dash was bouncing) and saw a cable right next to it disconnected. I left it disconnected not knowing what it was for. Turns out that same day I was replacing a damaged switch in the dashboard and noticed one cable going to the alarm was disconnected (Let me just clarify that I bought the boat used and it is my first boat).

So I go ahead and connect the cable to the alarm and when I fired the engine two beeps started to sound every minute or so. I then remembered about the disconnected cable in the engine and decided to connect it. Sound went away....
http://i1012.photobucket.com/albums/af248/jeanpablo/lancha/IMG00022-20090916-2132.jpg
I later discovered this cable is for the oil pressure switch. Weird thing is that next time I launched the boat, everything seemed to be ok until I wanted to accelerate. At this point a steady alarm started to sound and the engine to stutter (protection mode) until I reduced speed to idle. Because I had used the boat many times before I connected the alarm and that cable, I decided to disconnect both and continue my day. No problems at all.

To my point... I just read on a reply by Don S to another threat that the oil pressure switch cable must be connected in order for the fuel pump to operate correctly??

would that have something to do with the boat having trouble starting after sitting for a few months? also why did it work perfectly before without that cable connected?

Thanks
JP
 
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