85' 90hp mercury power loss

[rjsizemore]

I engine is very slow getting on a plane with just me. Will not plane with 2 people. This engine is on a 15.8 fiberglass fishing boat. The stator trigger both power packs have been changed new sparks plugs. This engine is an inline 6 compression ranges 125 to 130 psi except #3 is 118 could anyone help with my engine does it need rebuilding how much would it cost

 

[Fishin4fun]

Re: 85' 90hp mercury power loss

I have a complete 90hp powerhead with 142-148 lbs in all cyls, she runs great. Let me know if you are interrested. I will make you a sweet deal on her! and can have her delivered to your house in time to be on your boat this weekend.

 

[Clams Canino]

Re: 85' 90hp mercury power loss

Prop it to make 5500 WOT with just you aboard.<br /><br />Max advance set to 21 degrees.<br /><br />Throw a can of Mercury power tune through it.<br /><br />-W

 

[rjsizemore]

Re: 85' 90hp mercury power loss

well i dont have a tach so I cant really tell the rpms but doesnt seem to run like it should. Seems to me its not getting enogh fuel it will idle fine but if you put the throttle down fast it boggs and quits. the primer bulb still hard after this happened it is about 2 weeks old. Could my fuel pump be the problem I took the hose off while it was running and their was very little coming out is this normal or is their another way to check the fuel pump.

 

[rjsizemore]

Re: 85' 90hp mercury power loss

how can I check my fuel pump

 

[rjsizemore]

Re: 85' 90hp mercury power loss

how can I check my fuel pump

 

[Gus Mortimer]

Re: 85' 90hp mercury power loss

check fuel pressure at top carb with fuel pressure tester.

 

[NathanY]

Re: 85' 90hp mercury power loss

Compression on that motor is fine, does not need rebuilt. Sounds like to me that you just need to have the carbs cleaned, or rebuilt.

 

[achris]

Re: 85' 90hp mercury power loss

The IL6 90 hp should only be propped to 5000 rpm. They don't have the porting to cope with higher revs. Have you checked the usual suspects? Spark on all cylinders, firing on all cylinders, advancing the timing correctly, all carbs opening together, no choke shutters closed?<br /><br />Use the KISS principle? (Keep It Simple Stupid)<br /><br />Chris..........

 

[rollnover]

Re: 85' 90hp mercury power loss

Originally posted by Clams Canino:<br /> Prop it to make 5500 WOT with just you aboard.<br /><br />Max advance set to 21 degrees.<br /><br />Throw a can of Mercury power tune through it.<br /><br />-W

 

[rollnover]

Re: 85' 90hp mercury power loss

I might be interested in that powerhead. what is a sweet deal? How much

 

[rollnover]

Re: 85' 90hp mercury power loss

Hey you with the powerhead! you say you are from southern NH. I need you man. I have an in-line six the runs real bad. But it runs. how can I drop it off to you? Where are you?

 

[Fishin4fun]

Re: 85' 90hp mercury power loss

I have the powerhead, but I am not from NH. Email me at edward.abrahamson@us.army.mil and I will talk with you if you are still interrested.

 

[jimmbo]

Re: 85' 90hp mercury power loss

Had this happen to me too. Sounds like a dead cylinder or two. Check the plugs for spark. If not the problem, then see one or more of the carbs has a stuck float. Pukes fuel out of the bleeds when primer bulb is squeezed.

 

[rjsizemore]

Re: 85' 90hp mercury power loss

if i messed with the throttle linkage would it mess the timing up I screwed it in alittle so it would idle better

 

[jimmbo]

Re: 85' 90hp mercury power loss

Do you mean the idle stop, the timing advance limit, the linkage between the ignition plate and the carbs?

 

[rjsizemore]

Re: 85' 90hp mercury power loss

i messed with the one going to the throttle cable

 

[jimmbo]

Re: 85' 90hp mercury power loss

I doubt any adjustment on the throttle cable will cause your trouble, it might make the idle inconsitant or the shifting stiff. I think you have a bad switchbox.