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Charles, Marine Mechanic
Category: Boat
Satisfied Customers: 3976
Experience:  US Navy (Ret) Certified Mercury Marine Tech with over a decade of repair experience.
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I just purchased a 1988 268 sundancer with a 7.4 mercruiser

Customer Question

I just purchased a 1988 268 sundancer with a 7.4 mercruiser inboard outoaord engine. the enjine sound great but i only get 11 mph at full throttle. I the bow is up in the air and the stern is extremly low with a kind huge following sea type wave.
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Is there anything else the Marine Mechanic should be aware of?
Customer: not really
Submitted: 2 months ago.
Category: Boat
Expert:  Charles replied 2 months ago.

Hello, my name is***** will assist you.

Expert:  Charles replied 2 months ago.

Was the engine drive trimmed all the way down when this was happening?

Customer: replied 2 months ago.
im sorry i was waiting on an email resopnse but yes it was.
Expert:  Charles replied 2 months ago.

What drive and prop are on the boat?

Customer: replied 2 months ago.
Charles im kinda new to boats and I can't tell you what kind of prop i have but its*****
Expert:  Charles replied 2 months ago.

The drive is the big unit that is located outside the hull. It will say either Alpha, Bravo I, II.

Customer: replied 2 months ago.
Man, im sorry that im unprepared but wont be able to check that until the morning.
Expert:  Charles replied 2 months ago.

Thats fine, there are no time limits here. Just let me know when you can.

Customer: replied 2 months ago.
all i have to do is log back on with the answer?
Expert:  Charles replied 2 months ago.

Yes. your reply will come straight back to me and we can continue from there.

What was the full RPM that you got from the engine today?

Customer: replied 2 months ago.
about 4000
Expert:  Charles replied 2 months ago.

I really feel that the trim was not all the way down on the drive. If you try it tomorrow, press the down trim button until you hear the tone of the trim motor change. This will tell you that the drive is all the way down. If you were going by a gauge reading, the gauge could be bad or the sender on the drive could be bad.

Customer: replied 2 months ago.
when I pushed it to the max , it started cutting out kinda, then it she just slows down until i come back on the throttle. It sat up for six months and I dont know if the last owner winterized it or not but it doesnt get that cold hear. should I have drained it?
Expert:  Charles replied 2 months ago.

It is always best to drain the black and the manifolds, just to make sure. While you are at the boat, check the oil level on the engine. Make sure that it is not over full or a white milky color.

Customer: replied 2 months ago.
ok i will try it let you know. I hope it is that simple. Thanks
Customer: replied 2 months ago.
OK I will check oil again. it was kind of low but didnt know what kind of oil to put in that 7.4
Expert:  Charles replied 2 months ago.

Let me know what you see tomorrow and we can go from there.