View Full Version : Major engine issue 89 Maristar 240

06-12-2006, 11:13 AM
I have a 1989 Maristar 240 with 900+ hours on it. The engine is a 425 hp "high Performance" vs the other option for that boat which was the normal 330hp. I was running normal at about 2800 RPM and it slowed down like I was pulling back the throttle. My first reaction was to do just that and then it stalled. I tried re-starting and it would turn over and the first time or two, but then quickly stalled...the next couple times I turned the key it would just turn over, sounding sluggish like the batteries were low, and then it would not even turn over. The batteries, I have two, are both brand new and 800cca. I tried it on each one battery then I tried it on both at the same time. I noticed the engine was hot when this happened, but not pegged and I smeeled a strong burning oil smell... The oil is OK, could be changed, but not milky or empty. None of this seems too good to me, but I am not a mechanic and will need to take it to someone for serious look. If anyone has suggestions on starting to trouble shoot and diagnose this I would really aprreciate the feedback.

-john o

06-12-2006, 12:50 PM
That doesn't sound too good. You may want to try pulling the plugs and seeing how it spins then. It sounds like it ground to a halt and doesn't want to turn freely any more. I'm not sure what would cause that, other than an oil related failure of some kind. It's not normal for an engine to 'seize' while running unless it runs out of oil somehow. It doesn't sound like a battery/starter issue. I would suggest pulling the plugs and if it spins freely, do a compression test. There is a possibility that it could be in the valve train as well. Timing chain maybe? Broken rocker arm? push rod through the rocker?

I's suggest a compression test. It will give you a reasonable idea of how the internals of your motor are working.

I'm sure someone with more motor skills than me will have a suggestion for you. Hopefully it's not too serious.

Good luck.


06-12-2006, 05:24 PM
Thanks Bruce. That will be our next step is a compression test.

06-13-2006, 10:50 AM
Hey johno,

I've the same boat...I second the compression check...BTW, how do you know you have an HO 454? The only way I can think that I might is by the horrific price a paid last year for a replacement head after one was found to be cracked - compression in that cylinder was 62 psi. - all others were around 130 ish...mine has unknown hours but I'm sure equal to yours.

Someone here suggested that a head was a head for these motors but apparently the port shape IS different for the HO version so....

Good luck

06-14-2006, 01:09 PM

I spoke to Mastercraft and had them give me the specs/history of the boat by the serial number. The person there was explaining the nomenclature of the serial number and it has an H or HP in it and they said that was for High Performance and said that that boat came with two different engines...That was several years back, so maybe a little fuzzy on specifics, but that was the gist of it.

Hopefully that compression check will be done today...

Did you ever get a reason as to why or how a head might have cracked?

How did you know you had a problem? Were there any early signs?

I will get some photos posted for you soon.


06-14-2006, 08:08 PM
Hey John,

Actually mine started with a starting issue...I initially had my stater and alternator rebuilt which helped, I then moved on to running in a new wire from the key switch ("S" terminal I believe) to the solenoid - this made ALL the difference in my case (some fine folks at Mammock's Motor Electric here in Annapolis gave me that tip...that wire has to be PERFECT or you'll eat solenoids) so I ate a few solenoids and in fact need to change one out now - apparently 454's or just tough on staters/solenoids...

Another component was the carb which I rebuilt this month - made a bunch of difference.

So one day I did a compression check last season, just on a hunch and found a low cylinder (62 psi) which upon further inspection revealed the cracked head (between two cylinders - due to overheating...before I bought the boat) so I must have bought the thing that way not realizing - it really WAS NOT loosing alot of power.

I am VERY careful with engine temp as mine has no alarm so I monitor it constantly - never goes above 160 while running, maybe a 170 after sitting but immediately cools. Just now I am in denial or if it ain't broke don't fix it....

Sorry for the long post but in short - other than the starting issue which I beileve I've finely overcome (or come to live with) there was no real "event" that lead me to believe I had a problem, just sort of running sluggishly...

The compression check will tell a story, a leak-down test will tell more...

07-11-2006, 09:49 AM
First excuse the poor wording...I am new to the engine rebuild world so am looking for advice as well. We had the engine pulled and found it has a cracked block. One major crack on the top where it meets the heads and runs about 3 inches, another smaller one where you can see a rust spot running along it on the outside of the block. There are a lot of metal shavings in the oil pan. The guy who did this work (an independent marine reair shop) showed us all that was wrong. He said the valves were "mushroomed", cranks weraring unevenly, needs a valve job, "naturally" and maybe a few more things...He said to do all this would cost about $5000. Includes the pulling, tearing down, evaluating, completely re-building & machining new block, and putting back together...

My bro-in law, who is my partner on the boat, recently had a a guy put a rebuilt engine in his 67 El Camino. He says this guy is "really good" and is his own machine shop. He has said he can re-build with new block for $2600, or possibly repair old block for less once he sees it.

We would have the marine guy put it back together and back in the boat. He has quoted us $1000 to do this. That includes upgrading the rotor & cap to electronic ignition...So my question is this: Do we go to the 2 different guys to try and save $1000 to $1400 or just leave it with the marine guy for $5000? I am sure there are a lot of questions I should ask but have not...Any advice greatly appreciated!

07-11-2006, 10:56 AM
tough decision....

1) if the b-i-l's friend is really good, you shouldn't need to pay the marine guy a grand to reassemble things (just to have it disassembled again) - he should be able to deal with all the parts as is. Have the friend put the electronic ignition on it. Just make sure this friend knows there are some significant differences in marinized engines vs car engines (camshafts, heads, etc.)

2) if the marine guy did it all, you'd end up with a 'one throat to choke' repair (if there were any post-rebuild problems) - what's that worth to you?

3) In the end, it becomes a 'confidence and reputation' decision. If you trust the marine guy more, spend the extra. If you're confident that b-i-l's buddy is knowledgeable enough to deal with a marinized engine rebuild, go that way.

good luck- let us know what you decide.

07-11-2006, 11:25 AM
Thanks Neil. Just to clarify...the marine guy has already pulled and taken apart to learn what we know now...he has about $500 in it now. We would take the dis-assembled block to b-i-l's buddy then when re-built bring back to marine guy to re-install in boat. That along with electronic ignition would be another $500. But as you said, in the end I think it is a confidence issue too. Thanks for the advice.

07-11-2006, 11:43 AM
I think most machinist/rebuild shops could rebuild just about anything. One thing I personally have found is they have a harder time finding a "marine" source for parts. I would stick with the boat guy, if for no other reason, for future maint or "Warranty" problems. IMO

07-11-2006, 12:58 PM
if you decide to rebuild scrap any engine parts that have been damaged, cracked block, heads etc. do not weld and re-use them.

a marine long block or a complete motor would be my choice and have the guy with the most marine experience install the engine. also if it had a BB keep it a BB, don't swap it out for a SB to save money, you'll devalue the boat

of-course after it's all back together find out why it over heated

still some summer left get on it !


07-11-2006, 04:32 PM
Thanks Jeff.

Sorry to be so ignorant, but is what we have a marine longblock?? And when you say a complete motor, do you mean, buying one already rebuilt?

I assume BB & SB is big block & small block? It is a 454 high performance, 425 HP and we have said we want the same. I have been told that high performance & horsepower is from differrent size of pistons,type of pistons, and heads...is that correct?

We think it cracked because the drain valve on the side of the engine where the big crack is, was not working properly. We ran 3 gallons of antifreeze thru it, but maybe not enough or still held water somehow???

Any thoughts?


07-11-2006, 09:22 PM
long block and you would reuse your sheet metal intake & exhaust.
if you severely overheated I'd be concerned about the ex manifolds being damaged, warped.

complete engine would be a drop in motor with everything installed from the builder, manifolds, pan, pump etc.. might be hard to find one given the age of your boat.

www.skidim.com has two 496 cid base engines, HO and normal.