YSM8 and hunter 30

[newhunterowner]

I just recently bought a hunter 30. The engine is a ysm8.
The engine starts fine,but when first started the oil pressure is around 50 +/-
after I run the engine a while the oil pressure starts to drop to around 20.
The engine never seems to overheat,but i can't push the engine very hard.
The harder i push the engine or the longer i run it, the pressure drops til about 5.

This means i can rarely get more than a couple knots out of the boat.

I have read that the 8hp was too small for the boat.

What is the likely cause of my problems? we are considering rebuilding/repowering. Which is cheapest and most practical?

If repowering, what size motor should it have?

thanks

 

[Chuck Creel]

Dear guest,
!st of all Welcome aboard. Now to help with your delima. I also have a H-30 with a YSM-12 Yanmar that is original from 1979. It pushes the boat abt 5 MPH on calm seas and no wind. I am repowering to the 2Y15 from Yanmar because I plan on cruising some next year and will be facing some curretns of 2 MPH or better in places. Let me share an experience the wife and I had this year.
We left out ahead of a front and got caught with 30 plus MMPH winds on the nose and 4-5 ft seas. Running at full throtle on the YSM-12, we were going backwards at .5 Mph at times and barely holding our own when quartering into the swells. On 4 different occasions, the ENTIRE hulll came out of the water when cresting the swells.

My humble opinion, the engine is an auxiliary engine designed only to get you in and out of the slip. NOT cruising. If you have a solid hull then I would consider repowering. The H-30 is a GREAT design and will suffice very well for coastal cruising if you choose to go there.

HAppy Sailing.
Captain Charles Creel
www.gulftel.com/charlesc

 

[newhunterowner]

Chuck

Thankyou for replying. Like most owners, I don't think i will be sailing abroad much. A trip to the Bamahas would be nice eventually. Our first biggest trip will probl. be to the Keys. Right now we are just sailing around Charlotte Harbor in Punta Gorda.

Would the engine you recommended fit in the area the YSM8 is now? What modifications would likely have to be done?

How fast would that engine likely push the hull. (I know it will only go about 7 knots to begin with)? At this point evne the 5 knots you were getting would be a great improvement as I can usually only make about 2 knots on still water.

Does any body have any ideas about why my motor does what it does? Is it just old and needs to be retired/rebuilt?

Does any one know how those motors usually performed when in good condition?

Thanks

 

[J Page]

The symptoms you describe seems that when you power up, you start losing pressure prob. are passing oil past the rings. Do you see any obvious smoke or oil sheen behind the boat when powering up? If so then a rebuild might be in order. As far as other questions, yes the ysm8 is a drastic underpower for our boat. I have a 1979 hunter 30 with the ysm12 and mine is underpowered. Moving up to a three blade prop won't help much but some. For my sailing, the motor is fine but up here in Michigan, no currents, no tides and if I'm caught out in a storm, I did at least 3 things wrong already so I deserve it.

Pray for Wind,
Lugeman

 

[newhunterowner]

smoke/sheen

Thanks for answering
No, i don't see much smoke and no oil out the exhaust. The engine uses very little oil. I don't have alot of time on the motor since i bought it, but I changed the oil and have not added any to it so far. (I prob. have about 20 hrs so far).

I hate to put an outboard on (I like the looks of the boat, course i am biased). But a new Deisel is pricey, not to mention any modifications that would have to be made.

I really don't know what is up with this motor and don't have a clue which motor i should use if I repower.

 

[Clark]

The first thing that comes to mind on the oil pressure is that the bearings are worn. Oil pressure is generated when the pump encounters resistance when trying to push the oil through the passageways that terminate around the cam bearings rod bearings and crank bearings (primarily). Also, there are outlets around the valves. The cylinder walls, rings and wrist pins get lubricated by the splash from the pan. I've had a few old cars over the years that did the very same thing . . . when cold the pressure was OK but the pressure dropped as it got warmer all because of bearing wear. Another factor could be a worn oil pump.

Also, by the time the bearings are worn, the rings are too so you don't get the compression (=horsepower) that the engine used to have.

Sorry this sounds so negative but dropping oil pressure is usually indicative of a worn out engine.

 

[newhunterowner]

Thanks for replying.

I suspected that the bearings were worn. Esp. since i didn't see any signs of oil usage.
Now all i have to figure out is should i rebuild or repower.

Has any one repowered this sailboat and know what is involved.

I will try to find someone locally who can do the work.

The hull isn't in too bad of shape, there is a softspot in the cabin sole (cracks underfoot).
I am going to try and flood it with epoxy first. I have removed a cabin sole on a previous boat and believe me it wasn't much fun.