Problems all summer long
 

It all started towards the end of April when I put my boat in the water for the first time this summer. My boat is a 2003 supra launch ssv with the inmar 325 assault TBI engine. I checked the oil before I put the boat in the water and it was good. Afte the boat warmed up I was checking over everything and checked the oil once again and noticed it now had water in it. Well long story short on that part was I had the engine replaced because of a cracked cylinder. (Dropped off in april and picked it up around the end of may.)

Ever since the engine has been replaced and this was occuring during the break in of the new engine I notified the dealer that installed the engine that it was having a hard to start problem. Also another problem where when you would return to neutral the rpms would drop to around 200 or 300 and almost stall and other times it would stall. I had none of these issues before the engine was replaced. They first said it was the fuel filter and changed that. The problem still occured after that was replaced. (Sometime in May)

Now it is july and the problem is still here and now that said my fuel was bad. So they drained the tank and filled with new gas. Long story short the problem was still there. (July)

Now still July and I took it back with teh same problem and they said the computer was showing codes (81)Inj A low/open and (81) Inj B Low/open. Said they contacted indmar and they said inj driver was bad and ecm needed replacement. They replaced the ecm and it did not correct the problem so they put the original ecm back in. Now with the original ECM back in they said it was the map sensor. They replaced that at my cost and it did not correct the problem. (Picked it up beginning of august)

Took the boat back after the weekend with the same problems and the sent some run files to indmar this time. According to an email from indmar and info from the tech that it is normal for engine rpms to drop when returning to neutral. The tech at teh dealer said they found erratic issue with ignition circuit and IAC valve wanting to stay closed not allowing idle air to bypass causing the hard to start problem. THe replace the ignition key switch and the IAC valve and Im still having the same problem.

My boat never did this before they replaced the engine and for Indmar to tell them it is normal for the engine rpms to drop that low is ridiculous. You boat should not stall out just because you are returning to neutral. Im not going to mention the dealers name at this time but am looking for advice on what my next step should be. As of right now I am in this about $7,150.00.

Is the $7,150 just for the repairs? Ouch if that is the case.
Not sure what you can do except let them fix it again till they get it right. Is the engine work still under warranty?

Could be an intake manifold gasket or some other gasket causing a "vacuum" leak (Drawing in air through places other than the throttle body). A small leak that allows air in that's not "seen" by the MAP/MAF might throw the air fuel ratio way out of whack at low RPMs but might not flow enough air to have much of an affect at higher RPM. You could test by getting a propane torch (not lit) and release propane around the throttle body and intake manifold while it's idling. If it revs the engine when you spray a particular spot then you know that it's getting air there. 1) don't do this while the engine is really hot to avoid starting a fire (I'd run the blower and have a fire extinguisher handy just in case) and 2) don't spray it at a place where it will be drawn into the intake in large concentrations and give you a false positive.

Some people use carb cleaner for this purpose but it tends to eat at paint. You can use it but be real careful about letting it puddle on any painted surface. I suppose you could use starting fluid (ether) too but it's really flammable.

Sounds like they're trying to point the finger at peripheral issues that aren't covered under the engine warranty so they can milk you for a bunch more money.

Oh, ask the mechanic to do a compression test on each cylinder and tell you the numbers. Given the problems you're having with their engine I can't imagine they'd charge for it. I'm not sure what you should expect from your particular engine but they should all be relatively close to each other. If one or more is way low then there's your problem.

They could also do a leak down test on the block but that's a bit more involved.

More than likely it's the new block or some peripheral that they removed and reinstalled during the replacement process.

try advancing the timing just a little by turning the distribitor clockwise!

It's an '03 and still has a traditional distributor? My MasterCraft is an '00 and has distributorless ignition.

I guess it's a TBI so it would make sense for it to have a regular distributor since it isn't exactly bleeding edge technology to begin with.

Why have you paid for anything other than the engine replacement? They saw you coming and have been milking this for all its worth and more.

why take it back to someone who obviously can't fix it. do some research and find a good mechanic they will fix it.

this weekend
 

Well I will be checking all of these things this weekend when I get to our lake house. I have a compression tester so I will check the compression my self before I take it back in and have them check it to make sure they are telling me the truth. Thanks for all the advice on things to check. Will post back on sunday or monday with results. Thanks again.

i would put a vacuum gauge on manifold
, should be steady around 12-15
if not stuck valve, hence the map sensor issue

yes bad gas would freeze an injector

I don't know your engine/boat setup, but what about the throttle position sensor? If they replaced the engine, did they adjust it for the new engine?

Also, keep us updated as to how things are going. I feel bad for you that you have 7k into this and it is still not working. Dealer sounds like an issue to me.

winterize
 

I winterized my boat yesterday and have not had time to do a comp test or leak down on it. I did notice all of the plugs looked the same except for one. The tp still looked new compared to the rest. Also the casting number on the block is 10243880 which mean it is a 350...95-00...2 or 4...Vortec truck, Gen.I crate motors and "ZZ4", roller cam, one piece rear seal. DOes this mean they sold me a remanufactured engine and not a new. How do you get a 10 year old engine new?

Vacuum guage should read 18 to 22 and steady on a healthy engine not 12 to 15 as stated above...