How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jeremy R. Your Own Question
Jeremy R.
Jeremy R., MarineTechnician
Category: Boat
Satisfied Customers: 9020
Experience:  Multiple factory certifications 20+ years of experience.
Type Your Boat Question Here...
Jeremy R. is online now
A new question is answered every 9 seconds

I just bought my daughter a 1987 Starcraft with a 2.5 120hp

Customer Question

I just bought my daughter a 1987 Starcraft with a 2.5 120hp mercrusier. Two issues I noticed , heats up going slow but runs nice and cool when driving .
Hard starting , it takes several attempts , I'm new to I/o's , is there a trick ? It doesn't have a center button to push on the throttle just to add throttle in neutral .
Submitted: 2 years ago.
Category: Boat
Expert:  Jeremy R. replied 2 years ago.
The heating up a little more at idle than at speed is normal as long as it stays within it's range.The reason is the impeller in the leg probably is past due for being changed and it's weak.These older engines you push the center button to remain in neutral and then pump the throttle 2 or 3 times.The carb has an accelerator pump on it and this will help get it started faster.Alternatively the choke may be bad or just not adjusted properly.It's a bimetal choke so it opens as the engine comes up to temperature.At cold the choke plates should be closed.You can unscrew the 3 screws on the side of the choke plate and rotate it a little to help adjust this.But just make sure when the engine is warmed up that the plates are open. Otherwise you'll run too rich, waste fuel, and foul spark plugs.
Customer: replied 2 years ago.
Thanks . The choke makes sense.
I took the boat on a 2 hour ride at varying speeds and also at idle.
Sometimes it get near 200 while below 1000rpms , and cool off as I go above 1200. Once cruising it stays near 115-120.
Is it possible the pervious owners removed the thermostat ?
Should it remain at a steady temp once warmed up like a car ?
I'm only familiar with OB.
Expert:  Jeremy R. replied 2 years ago.
They may have with that big of fluctuation but it should never get to 200 so that tells me the pump needs redone.