1985 90 HP Mercury fuel problems?

[drdetroit3]

I have a 1985 90 HP Mercury, went to the lake the other day, 32 degrees!!! I went to start the boat , chocked it it started, but would die if I gave it any gas? I started it again and when it was going to stall push in hechoke and it revs alittle but every time I gave it any gas it died??

I am thinking change the fuel filter (does anyone know where it is located)?
Change the spak plugs.

any other suggestions??

I am a carpenter, not good wit hmotors, trying to sell th bat o trying to avoid taking it in the shop. Ran great a few nths before.

Thanks, Mike

 

[Lone Duck]

Re: 1985 90 HP Mercury fuel problems?

I have a 1985 90 HP Mercury, went to the lake the other day, 32 degrees!!! I went to start the boat , chocked it it started, but would die if I gave it any gas? I started it again and when it was going to stall push in hechoke and it revs alittle but every time I gave it any gas it died??

I am thinking change the fuel filter (does anyone know where it is located)?
Change the spak plugs.

any other suggestions??

I am a carpenter, not good wit hmotors, trying to sell th bat o trying to avoid taking it in the shop. Ran great a few nths before.

Thanks, Mike

(1) make sure you have good fuel(no water ) (2) Vent tube is clear (3) All lines and connections are air tight (4) bulb is in good shape and pumps up hard (5) check fuel pump diaphragms are in good shape and screen is clean. Fuel filter could be in the line from tank to fuel pump or between fuel pump and carbs. If all is in good order,then it is time to remove carbs and clean, maybe new carb kits with floats. Tell us what you find before doing carbs.

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Sorry don't mean to sound dumb! but how do I check the fuel pump diaphragms are in good shape and screen is clean.

I assume fuel is good I had a little left in the tank and added 7 new gallons, how do I check for water?

Thanks, Mike

 

[oldman570]

Re: 1985 90 HP Mercury fuel problems?

Sounds as tho your motor is cold blooded and it might take it longer at a fast idle to warm up than what you are use to beening that it was only 32 degrese out, rather than say 60. Some older mercs are cold blooded and they will stall until the get up to temp and then work good. Try letting it warms up good and you are getting warm water out of the tell tail, then see if it will work better. Otherwise do as Lone Duck states. JMO
Oldman570

 

[Maxz695]

Re: 1985 90 HP Mercury fuel problems?

View attachment 180357 Here is a 70 HP just to give you an idea. The diaphram is located inside the fuel pump indicated in the picture and the screen is located inside the black plastic cover and may need cleaning. Try that before undoing the fuel pump.

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

OK, I went out today got the boat running, after about 10 seconds it would start to stall.
If I squuze the fuel ball it would keep running so I assume its the fuel pump.
Next question where is the fuel pump?


The first one is attached to the motor and has a screen in the bottom?
The second with the wires id attached where the fuel come into the motor from the ball?

I also call a local shop gave them my serial number 6623946 85 90 HP inline 6) and he said the old style is not avalable but the new style is but he is not sure if it will work??

Any help here would be great, thanks to those that have already posted.

Mike

 

[narvlebenoit]

Re: 1985 90 HP Mercury fuel problems?

The top picture is the fuel pump you proble order a kit here at iboats its easy to put in.l

 

[carholme]

Re: 1985 90 HP Mercury fuel problems?

Your s/n comes up as:

MERCURY - ( 90 H.P. (1985 ))
Serial No: 06623946 Model No: 1090625

Parts list for model 1090625:

90/115 H.P. (INLINE) - Mercury, Mercruiser, Force, etc. Parts Lookup

See your pumps under FUEL PUMP AND FUEL LINES (OLD STYLE FUEL PUMP)

The pumps may not be available but everything is there to overhaul them.

If you want to see how the pumps work, here is a link to the condensed version of the Clymer manual. Download it soonest to your computer as the link is short lived.

Small Engine Repair Reference Center Home: MERCURY - MERCURY IN-LINE SIX-CYLINDER MODELS (1969-1988).

Gerry

 

[P3FE]

Re: 1985 90 HP Mercury fuel problems?

Assuming you are using electric choke. Correct!

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Thanks guys, not sure if I can tackle this rebiuld myself, not sure exactly what parts I will need?
Is it difficult or pretty straight forward once I get it off?

Mike

 

[carholme]

Re: 1985 90 HP Mercury fuel problems?

If you look at the parts list under Fuel Pump, old style, you will see the pump disassembled and the kit for the check valves. Here is a picture of the kit on ebay and you can see that it comes with instructions.

Quicksilver Mercury Check Valve Kit 21-30430A14 #84 | eBay

Doubleclick on the picture to blow it up and see what you get.

Gerry

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Gerry,

Thanks so much for your help!
I think I will give it a try, so is the part above the one for my motor??

Mike

 

[carholme]

Re: 1985 90 HP Mercury fuel problems?

Yes it is. See item 2 from the parts list

Mercury, Mercruiser, Force, etc. - FUEL PUMP AND FUEL LINES (OLD STYLE FUEL PUMP) - 90/115 H.P. (INLINE)

Gerry

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Thanks, ordered the part, let you know how it goes.

Mike

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Gerry,

Got the rebiuld kit today, have a ? do I use any gasket seal on these?

Mike

 

[carholme]

Re: 1985 90 HP Mercury fuel problems?

Mike

I have never used anything on the pumps and never really seen a need to.

Good Luck with your project.

Gerry

 

[drdetroit3]

Re: 1985 90 HP Mercury fuel problems?

Gerry,

I rebuilt the pump and went to lake for a test drive, started right up and ran the best it ever has!!!!
Thank you so much for your help..

I did notice today a few times when I went to start the starter would click two or three times in a row then start right up?
I guess I need to replace the starter? At least that should be pretty straight forward.

Thanks again for your help.

Mike

 

[kjspylite]

Re: 1985 90 HP Mercury fuel problems?

The clicking sound could be the starter solenoid. A much cheaper fix and very easy.

 

[mercuk]

Re: 1985 90 HP Mercury fuel problems?

The clicking sound could be the starter solenoid. A much cheaper fix and very easy.

+1^ very good advice ^
It is exactly what you have pictured in the second photo with the chunky yellow and red wires going to it.. I would change that before thinking of starter motor replacement. Good luck let us know how you get on.

 

[Lone Duck]

Re: 1985 90 HP Mercury fuel problems?

Gerry,

I rebuilt the pump and went to lake for a test drive, started right up and ran the best it ever has!!!!
Thank you so much for your help..

I did notice today a few times when I went to start the starter would click two or three times in a row then start right up?
I guess I need to replace the starter? At least that should be pretty straight forward.

Thanks again for your help.

Mike

Check all your connections first. A click click click then start usually means a bad ground or + wire to solenoid or starter. Could also be a poor connection a batt.