20 year old 470 ran well 2 hours then limped

[Cavaliermike]

Hi,
I'm a newbie here. Just boat an 89 boat with a 470 in it. Filled it with gas and it ran beautifully for about 2 hours...then died...it restarted with difficulity, but would only turn about 1000rpm and mainly die when the prop engaged...barely limped back to the dock...oil pressure showed about 80 or so, temp 120-160...all fluids look good...are there things I should try and do or just call the mechanic...the plug wires, coil and the distributor appear pretty used...could there be a fuel contamination problem?
Thanks for any and all help...
cavaliermike

 

[HT32BSX115]

Re: 20 year old 470 ran well 2 hours then limped

the plug wires, coil and the distributor appear pretty used

Howdy,

Appearances can be fairly deceiving and usually aren't an indication of performance.

Just from your description it sounds like a fuel problem.

You should ensure that you have adequate fuel delivery. You may have a partially plugged filter or tank screen, a carb or fuel pump problem.


Regards,


Rick

 

[Rocky_Road]

Re: 20 year old 470 ran well 2 hours then limped

First guess is fuel starvation...probably from clogged fuel filter.

Today's E-10 ethanol pump gas will 'clean' any crud build-up in the tank, and lines...and end up in the filter. With any luck, you have a spin-on fuel/water seperating filter, between the tank and the fuel pump. If not...make that your next project!

 

[flatiron14]

Re: 20 year old 470 ran well 2 hours then limped

I agree with Rocky Road. Ethanol, when put with regular gasoline, acts like a solvent of sorts and breaks down garbage and puts it in your fuel lines and causes clogs and all sorts of problems.

 

[a1nowell]

Re: 20 year old 470 ran well 2 hours then limped

Mike,
I have a M/C 470 that did that to me about a month ago except I could not get it to restart. I pulled the fuel pump off and was about to convert to an electric . I decided what the heck, and I took apart the old fuel pump that was frozen up. You cannot believe how much crude was in the pump. The vent port that vents back to the carberater was completely packed with solid material. I cleaned everything up, put the old pump back on and it cranked right up. I now have a water seperator filter plus a clear inline filter on the fuel line.

Hope this helps,
Larry

 

[Cavaliermike]

Re: 20 year old 470 ran well 2 hours then limped

Thanks all...each of you display the true delight of boating...having fun and helping each other....Mike