1997 3.0 mercruser engine problems need advice , please help

[Bayliner1997]

Okay ill try to make this short, I just bought this boat right before summer and paid alot for it. its a 1997 baliner capri 19ft. with the 3.0 mercruiser LX , when i bought it the guy said it had a idle problem when cold and he would have to warm it up at the dock before takin off. He said he had it serviced regularly and just had the carb rebuilt and had recipts for it.. anyways this is the problem, after a couple of minutes at full throttle it started pinging like hell, and before i knew it it was really idleing bad so i did compression test and had 0 compression on one of the cylinders , all others were good, so i pulled the head off and found one of the exaust valves had chipped and went out the exaust and did not do any damage to the piston or cylinder walls so i took the head to a machine shop to have a new valve put in and when they were grinding down the valve ceat area they found a hairline crack where the valve ceats, they said eventually it would leak water into the cylinder and they could have it welded and fixed for a couple hundred bucks, i didnt have the money for that so i had them pop in a new valve and put head back on engine with new gaskets and such and checke the compression and it was great, but still had that idle problem, took it out on the water again and the same thing happened started pinging like hell and running bad again , so i knew the valve chipped again, and then the head gasket blew, pulled the head and found the valved chipped again and water started to leak in cylinder like they said it would . so my debait is should i have the head fixed and put it back together or buy a new longblock on ebay for 2,500 , because even if i put it back together i know im gonna have that idle problem and i think it could be a timming issue but i have advanced and retarded the distrubuter to try to get it to idle a 700 or so but it shakes like hell and dies , i had to advance the distributer to let it idle at 1,000 rpm so it wouldnt die,(this is before i lost compression) and my timming marks and the timming cover have corroded and part of it is gone due to that so im not sure what to do, i dont have alot of money and the short block is ready to pull out but is there a good way to check the timing with the head off? wondering if the timming can change internal where the chain is? just wonderin what i should check before removeing the block if i dont have to. i always ran premium fuel in it, so i dont know if the carb got clogged up and leaned it out or if its a problem with the timming in the bottom end, because i know pinging is usually detonation , this thing supposovley has low hours on it . any advice would help,

 

[Bondo]

Re: 1997 3.0 mercruser engine problems need advice , please help

Okay ill try to make this short,

Ayuh,.... Welcome Aboard,...... Actually,... Longer would be easier to Read,...
Paragraphs,+ punctuation Help,.. Alot...

so i dont know if the carb got clogged up and leaned it out

My waGuess is it's going Lean,...
I doubt it's the Cam timing,+ I can't believe you've done all this work Without timing the Igintion.....
You probably otta check,+ change the Fuel filters too,..

There's factory manuals up in the Adults Only section of this forum,.... Have a Look...

 

[fat fanny]

Re: 1997 3.0 mercruser engine problems need advice , please help

Bayliner as Bondo said , and start reading in the stickies section to educate yourself especially on timming procedures. I know $ is tight but if you don't spend it now your gonna later. If anything get a new head or reman pull the engine flush and clean and research your next steps theres allot of good usefull info in the stickies.

 

[cr2k]

Re: 1997 3.0 mercruser engine problems need advice , please help

Gee I wonder if the slight crack was spraying water on the hot exhaust valve and making it crack.

It seems odd that you didn't have a few hundred bucks to fix the head but now are looking at spending 2 grand on a new engine?

 

[havasuboatman]

Re: 1997 3.0 mercruser engine problems need advice , please help

Cr2k is right on the money.
Your crack is getting bigger as the engine is heating up. The pinging you are hearing is that water getting into the cylinder and raising the compression to the point or detonation. (like a diesel engine) This increased compression is also what blew out the head gasket.
Now, I hate to rub salt into the wound, but saving that couple of hundred bucks seems a little dumb now doesn't it? Putting a know defective MAJOR componant was probably the... Well, you should have known better.
But before you go throwing more more money away, fix what you have. To replace a motor because it idles poorly is asinine.
Replace the head, and don't cut corners this time. If your are still idling rough, fix that next.

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

I know it seems dumb that i didn't fix the head at the time but i had plans with freinds to go out to seafair (hydroplane races) the next day out on the water so i just needed to get it running, and the water had not started leaking yet, also the headgasket blew out on a totaly different cylinder than the one that started to leak water the second time.

I did try to time it at first too, but like i said the positive timming marks on the timming cover are gone. But im gonna have to fix the head now for sure so does anyone know where to find a head? Im gonna either fix or find another used head and get the carb gone through again and slap it back together and time right and hopefully she will run good. Anyone know a good place to get a decent deal on a gasket set too? Im a pretty good car mechanic but im new to the marine engines.

 

[bruceb58]

Re: 1997 3.0 mercruser engine problems need advice , please help

Curious, why did you not use a timing light and set the timing correctly? Did you torque the head dowm with a torque wrench using the tightening sequence described in the manual?

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

I did use a timming light, If i remember corectly i was supposed to set it at like 2 degrees positive and the positive timing marks are gone due to corosion on the timing cover. I used a jumper wire for the distrubuter also just like it said in the manuel. I torqued the head correctly also with my snap-on torque wrench. I think the distributer was set correctly , because it would idle at 700 rpm before i messed with it but it shook like hell and died sometimes . maybe the head was already cracked when i bought it. I bought it from the original owner and he was like 80 years old and he never reved it up . and my first time out i full throttled it and then all the problems started.

 

[CharlieB]

Re: 1997 3.0 mercruser engine problems need advice , please help

Rusted/corroded exhaust manifold will allow water to spray back onto an exhaust valve.

While you first had the head off did you notice the color of the piston tops?

If they were CLEAN, as in steam cleaned, then it would be wise to pressure test the exhaust. Over ten years it quite well may be a problem contributing to your repeated valve and head gasket failure.

Replace the head, either with a new or good used from one of the marine recycler/salvage yards. It may be possible to also get a low hours exhaust. Either way, do it right, or as you now know, it won't be long before you will be doing it again.

 

[180shabah]

Re: 1997 3.0 mercruser engine problems need advice , please help

everybody s quick to jump on the crack as the source....I have to go with Bondo on this one. pinging = lean or incorrect timing. detonation likely caused the valve/head issue. Install a water seperating fuel filter, probably don't have one. Start with good fresh gas. Premium is not required, if it actually makes a difference, then you have other problems. Replace the head - don't get cheap. Agree that the exhaust should be tested. Take it easy on the WOT runs, especially on an engine that you know ain't right yet.
Your description of an idle problem - "runs rough when cold" sounds like a carbed 3.0 but could be related to not having a proper tune up. could also be contaminated fuel, exhaust leak, carb needs rebuilt etc, etc.....

Slow down, and tell you "buds" they will just have to wait for another ride - or get thier own boat. Your learning the hard way but, it is always cheaper to do right, than do it twice.

 

[victorc1]

Re: 1997 3.0 mercruser engine problems need advice , please help

Hey, I bought a 1996 Monterey 180 SCR with a 3.0 LX in June 2009, I got tired of guessing for repairs so I rebuilt the motor, didn't spend the 2500 your planning on spending, I spent a little less than 1/4 of that. The internal parts I used automotive parts and the rest I bought on that auction site. The idle problem you have could be a filter, check the filter on the fuel pump.

 

[fishrdan]

Re: 1997 3.0 mercruser engine problems need advice , please help

I did use a timming light, If i remember corectly i was supposed to set it at like 2 degrees positive and the positive timing marks are gone due to corosion on the timing cover.

What ignition do you have on the engine? Check out this Service Bulletin if you have the EST ignition and 1997 3.0LX Sterndrive Engines: S/N 0K001529-0L000000 If you are setting the timing at 2* BTDC, that might be causing your problems....

http://www.boatfix.com/merc/Bullet/98/98_14.pdf

For your timing marks, is the tab completely gone or just rusty? If it's just rusty you can shine it up with a small SS brush and mark your setting with some white paint/finger nail polish/etc. Same with the TDC mark on the dampner.

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

Thanks for all the advise everyone. I am gonna try to find a used good cylinder head and then have it checked out and then ill put it back together and time it correctly and Ill have the carb rebuilt again . The fuel filter looked good but i will replace that too. Ill have to get one of those fuel-water seperators too because im pretty sure i dont have one. If anyone knows where to find a Cylinder head please let me know. Thanks

 

[bruceb58]

Re: 1997 3.0 mercruser engine problems need advice , please help

Also, are you setting the timing properly? There is a definite procedure outlined in the manual to when you jumper it. Has to be running first..then add the jumper.

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

I was goin by the book when i was timming it and I will definately go by the book when i do it again.

 

[fishrdan]

Re: 1997 3.0 mercruser engine problems need advice , please help

1997, you do have a 97 3.0LX, correct? Did you read that service bulletin I posted?

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

Yes I read that sevice bulletin. Thanks alot, Im still a bit confused though are they saying to set it at 1 degree positive?

 

[Don S]

Re: 1997 3.0 mercruser engine problems need advice , please help

Thanks alot, Im still a bit confused though are they saying to set it at 1 degree positive?

There is no such thing as 1? positive. Only Before and After.
Set it at 1? AFTER just like it says in the bulletin and shows in the picture at the top of page 2 of the Service bulletin.

 

[Bayliner1997]

Re: 1997 3.0 mercruser engine problems need advice , please help

Ok got it, I will be sure to set it and 1 degree After TDC, My buddy tells me that crack where the valve sits is why it wouldn't idle, even before it was leaking water, and even though i had good compression before the valve chipped, I guess it was probably cracked when i bought it dammit.

The guy provided recipts from the boat shop showing a tune up and carb rebuild a couple months before i bought it, He also had a complaint on the work order that said it wouldn't idle, so i figure it was internal if they couldnt figure it out and thats probably why he sold it..

So i am gonna bring the head to the machine shop and have them weld it and fix it, unless i can find a good used head for a ok price.

Thanks for all the help , ill let you guys know the outcome of all this shortly,