Blown Head Gasket on 3 L Mercruiser?

[jimmmy]

I recently bought a 89 Oliver1650 with a 3 L Merc. The beast was running poorly, so I drained and flushed out last years gas (and water) and had carb rebuilt by mechanic. He also installed exhaust flapper valve as it was missing. After 4 weeks just got it back in the water!!! Runs smooth but still won't go over 2600 RPM under load. In neutral will rev to 4500. With 4 adults in the boat can't get it to plane??<br /><br />Looking for advice!! Still the carb? Coil?Timing? (Compression test was good)

 

[iwldntli2u]

Re: Blown Head Gasket on 3 L Mercruiser?

Is that at WOT? Does it sound like it is boggin down? Have you checked you prop size? Does it make any other noise? Tells us more about your problem.

 

[jimmmy]

Re: Blown Head Gasket on 3 L Mercruiser?

Yup! That's at WOT!! She gets to about half throttle and bogs a little if you give her more. Also hesitates a little when you first give her throttle. Have tried prop change. Went from 4 blade 23 pitch to 3 blade 19 pitch which made very little difference. When I bought the boat, the carb had just been rebuilt. My mechanic, then had to re-rebuild it, as he said it was flooding. Maybe it still is?? I've heard people say, once a carb gets pitted by water, no amount of rebuilding will fix it and you need a new carb??

 

[jimmmy]

Re: Blown Head Gasket on 3 L Mercruiser?

Anybody out there willing to add their 2 cents?

 

[Ralph 123]

Re: Blown Head Gasket on 3 L Mercruiser?

Sounds like one too many carb rebuilds. If you have the $ why not go out and buy a brand new Eddlebrock or Holly marine carb and elliminate that as an issue once and for all. That is what I would be inclined to do.

 

[cajunglen]

Re: Blown Head Gasket on 3 L Mercruiser?

Pull some plugs see if they are black (soot) if they are, most likely still flooding. if your carb was pitted really bad at top of bowl vacuum might be pulling fuel between gasket and bowl,I've seen some pittrd bad enough they even have pinholes between carb throat and bowl. that one would leak fuel after shut down and add it to the oilpan. owner checked oil level and found it to be about two quarts over full.Could have blown!

 

[jimmmy]

Re: Blown Head Gasket on 3 L Mercruiser?

Sent the boat to a new mechanic (got fed up with old one after 4 weeks!!!) They found a blown head gasket between #2 and #3 cylinders. Head warped and gone out for machining. This explains why it revs to 4500RPM in neutral but under load could only get 2500RPM. First mechanic apparently did 2 compression checks....don't you think that would show up?? Anyhow, seems like we finally found the cause....I HOPE!!!

 

[jimmmy]

Re: Blown Head Gasket on 3 L Mercruiser?

Anybody hazzard a guess on what kind of repair bill I can expect for blown head gasket with machining the head?

 

[MrDumb]

Re: Blown Head Gasket on 3 L Mercruiser?

I just replaced my head gasket and t-stat myself on a 3.0l for $68.00 for all the parts. But I had all said and done atleast 10 hours labor in it. So if you figure a Marine mechanic @ $60/hour theres $600.00 labor, $40.00 re-deck/magna-flux, $70.00 parts. Theres $700.00 to have it done by a mechanic. Go figure, that is why I did it myself!

 

[denniz]

Re: Blown Head Gasket on 3 L Mercruiser?

$70.hr x 10 hr= $700.00 plus machine shop and parts..If I used both hands I could have it done in 5hrs. Apparently your first mechanic NEVER took a compression test. HE LIED to you plain and simple. Id ask for my money back. If I screwup like that at our shop you wouldnt have to ask for a refund ITS expected.

 

[Northern Eclipse]

Re: Blown Head Gasket on 3 L Mercruiser?

Jimmy I think you should be in for a about 500 to 600 loonies this is a common repair on the older 3.0l.If you have any spare change, you might want to consider doing the timing gears also the parts are cheap enough.