Mercruiser Engine Blues

[koicarp]

Have been experiencing engine problems on my 260Hp Merc Engine 5.7L, engine start to misfire under load especially when towing toys in turning tight corners (2200-2800rpm). Engine lacks power and misfires, changed the fuel seperator on the engine which helped heeps. But engine still still seems to hold back when running at full throttle 4000 rpm max. Engine starts fine when not under load no misfire or holding back any ideas?

Just wondered what is the max revs of the engine thought it would do 4500?

Ski is a PRE2000 1997 with low hours 400, new to ski would appreciate any feed back or experience from Tige owners.


Andy

[ghollow]

There are several things you might try that are not real expensive. Check your distributor cap and rotor and replace if they are too corroded. Replace your spark plugs. Run a bottle of Chevron Techron Fuel Additive in your next tank of fuel. Spray a can of carberator(?) cleaner through your carberator or throttle body. You might want to try replacing your fuel seperator again. If you had a lot of water in your tank, it may have filled up with water again. You should also keep your tank filled when not in use. You will get less condensation on a full tank.

[koicarp]

Mercruiser Blues

Thanks for feed back, I was going to try distributor cap plus rotar arm, just did not want go through just replacing everything. I disassembled pump and checked diaphram which look ok I really think it is fuel as changing the fuel water seperator really made a major improvement, would like to just sort out the last little bit.


Thanks for heads up and I try your suggestions.

What is maximum rev range this engine should go to?


Regards



Andy

[ghollow]

mine will run up to almost 5000rpm. I do not suggest running it that high for qa very long period of time. I usually try to keep mine under 3500rpm unless I am making a hole shot or showing off. The engine is built to run at waterskiing speed which is usually about 42 mph or less. Is your engine carburetored or fuel injected? Let me know and I can check the service manual

[latchstige]

If this only happens in tight turns you might be experiencing cavitation on the prop. That could mess with the engine. Not a mechanic but that could be a problem.

[koicarp]

Mercruiser Blues

Hi Ghallow,


My engine is Carb 260hp, it will not pull 5,000 rpm only 4000. I see you have 98 PRE2200 do you have injected Merc or Carb? I am based in UK and here the spares are expensive, hence the reason why I do not want to try changing lots of bits.

I have ordered serivce manual for Merc web site which should help a bit more.

Regards



Andy