1975 F-36 Engine issues!!

gofish103 · Post by **gofish103** » Wed Jul 06, 2011 10:49 am

I have twin 440's.

Went out Saturday on lake erie, right off the bat coming out of the marinia the port engine started stalling. made it out of the channel into the main lake, eased into the throttles got the engines up to 3200-3500 rpm and had no power to get up on plane. then the engines started getting hot. turned around to get back into the marinia, at idel the engine temps came back down. and both engines started stalling.

kept losing the engiines trying to get into the dock!!! thank goodness for the neighbors willing to help get me into the dock!!!

Now keep in mind that last July I changed all fuel filters on the boat and they have minimal hours on them.

Once at the dock, I pulled both fuel/water separators and dumped the fuel that was in the cannisters into clear bottles to check for water none was visible.

the port side cannister was as clean as new. the fuel had a good light yellow color.

the starboard cannister had about a 1/4 inch of crude in the bottom of it!! The fuel was a darker orangish color to it!!!

cleaned the canisters, replaced the water separator filters and the inline fuel filters next to the carbs.

removed the spark plugs from the starboarboard engine and the port side plugs appeared fouled and the starboard plugs appeared normal. I replaced all 8 plugs and set the gap to .35

removed four plugs from the port engine and they appeared normal. checked the gaps and they were ok.

both engines fired right up on the first turn of the key.

Sunday afternoon adventured back out. stopped at the marinia fueling dock, put approximately 50 gallons in each tank. got out to the main part of the lake, eased in the throttle got up to around 3500 rpm's and still could not get up on plane. again engines got hot. backed the trottles down to idle and temps came back down.

from the beginning, both engines were sharing tanks. on the second trip out, I isolated the fuel tanks to each engine. and had the same issues!

I've come to the conclusion that it is definetley a fuel issue and that the starboard tank is an issue with the crude in it and will more than likely have to be cleaned out. but is there a filter on the inlet end of the fuel line within the tank???

Any suggestions???

also, this boat has four tanks, two within the salon, and two under the aft deck. the previous owner had never used the aft tanks and they are shut off at the tank. but tapping around on the tanks they sound like there maybe something in them.

I thought that I have read in previous posts about the fill tubes being crossed. I have four fill tubes (2 port side forward and aft and 2 starboard side forward and aft). I only put fuel in the forward openings assuming that they feed fuel to the forward tanks.

any input would be greatly appreciated!!

Stripermann2 · Post by **Stripermann2** » Wed Jul 06, 2011 11:50 am

I have changed my fuel filters and separators as much a 4 times a seasons.

Be sure the manifold is closed off for the fuel tanks you're NOT using, as to no draw air.

You don't say what temperature your engines are over heating up to...rw or fw cooled...?

My guess is that you have a fouled bottom and running gear. This coupled along with the likelyhood that your water intake scoops and seacock are clogged or restricted, causing the over heating. And with this condition, you can not get up on plane. At the rpms you mentioned, you should easily be able to.

Spend a few bucks, have the boat hauled and cleaned...then go back out and run her. Good luck.

prowlersfish · Post by **prowlersfish** » Wed Jul 06, 2011 12:57 pm

I agree Fouled bottom making 3500 rpm and not getting on top is not a fuel issue .

gofish103 · Post by **gofish103** » Wed Jul 06, 2011 9:21 pm

the bottom and running gear was cleaned at haul out last fall, and the boat has only been in the water since beginning of may of this year.

Big D · Post by **Big D** » Wed Jul 06, 2011 10:29 pm

Dam ethanol

prowlersfish · Post by **prowlersfish** » Wed Jul 06, 2011 10:52 pm

Did the boat run ok at 3500 before ? and not now ? if so its the boat not the engines 3500 rpm is 3500 rpm , some has change with the boat , start with the running gear.

k9th · Post by **k9th** » Thu Jul 07, 2011 9:46 am

Only other thing I can think of would be trim tabs - if they are in the full bow down position that may cause issues with getting on plane.

But I agree with Paul, 3500 RPM is 3500 RPM and you are generating sufficient HP to get on plane.

stevocom · Post by **stevocom** » Mon Jul 11, 2011 10:23 pm

What part of lake Erie are you on?