150hp tower not getting enough power

[maagee79]

Ok I would like to thank everyone ahead of time for your input. I have a 1974 1500 incline 150hp. Last year I restored a 1976 15ft checkmate and put this motor on it. After a couple of months the motor started fouling plugs I could replace two and it would blow them all out. Today I started the boat from the winter it started fine just like new after letting it run for a few minutes I pulled one plug from each carb the top two were fine the bottom plug was covered in oil. I assume there is a problem with that carb. So all things are running through my mind is that the reason I wasn't getting the speed I was hoping for. I would top out at 43mph on a gps. Im running a 19p prop. Also I forgot to mention the last time I went out last year I put 93 octane gas in it no fouled plugs that day. Does anyone have any suggestions? I am a member on the checkmate site and others are getting up to 60mph with less motor than I have. Again thank you for your suggestions and or help.

 

[jerryjerry05]

Re: 150hp tower not getting enough power

First do a compression test.
Then a spark test.
That check OK,then a carb and fuel pump rebuild.
Then replace ALL the hose on the motor.
Ethanol is a bugger.
It's delaminating older hoses and melting the inside of some and it goes right to the carbs/pump.
Then after all that check for water in the gas.
Install a filter between the pup and filter.Wally World G12 or G2 depending on hose size.

 

[maagee79]

Re: 150hp tower not getting enough power

All of that was done before installing motor on boat except for replacing hoses.

 

[maagee79]

Re: 150hp tower not getting enough power

Any other suggestions would help. The motor has good compression 130 all the way across the board.

 

[aussieflash]

Re: 150hp tower not getting enough power

With normal weight load say 2 adults and gear fuel etc you should be reaching your max RPMs(to spec) say 5600-5800 for example.
I only use 95 octane in my outboard.Its never tasted ethanol......nor has my V8 holden (6 ltr Chevy).
In Australia we still have a choice of fuel...91 oct + 10% ethanol...95 oct.....98 oct.

 

[Faztbullet]

Re: 150hp tower not getting enough power

Which cylinders are fouling??

 

[Chris1956]

Re: 150hp tower not getting enough power

You should be seeing ~60MPH with that setup. I ran a similar setup with a 21P prop and got about that speed.
With motors of that age, sometimes water getting into the cylinders is an issue. See if the spark plugs are steam-cleaned (real clean like brand new). If so, that can mean water infiltration. if not maybe the carbs are flooding?

Check the spark plug wires for arcing to ground. The bottom ones especially. You should hear the snapping of the arc or see the flash.

The original floats can be disolved by the alcohol in our fuel. Replacement floats are hard plastic and can crack. If you suspect carbs, it makes sense to clean them, use new gaskets, floats, inlet needles and seats.

 

[maagee79]

Re: 150hp tower not getting enough power

Ok sorry been a while since I was able to read. Last year I rebuilt the cards before even going out on it. Today I went out and it would bogged down. I think it was getting too much fuel. I could unplug the fuel line run it till it was about starving for fuel plug it back in and go. It would jump out of the water. Then it sounded like I couldn't get it to rap out. I had the throttle pegged and not enough power. Itwould still run 40 to 45 ish I didn't gps it though. Im thinking it running too richhow do I lean it out? Im worried about making it too lean and scoring a cylinder. So any help would be appreciated.

 

[aussieflash]

Re: 150hp tower not getting enough power

Sounds like its gagging on fuel.Check float heights to spec.Check floats for damage and/or needle seat assembly not sticking.

 

[maagee79]

Re: 150hp tower not getting enough power

Ok great can someone help me with that explain in detail what to do. Just got home and there is fuel everywhere under cards.

 

[wired247]

Re: 150hp tower not getting enough power

I'm going with float level too high and flooding at higher speeds.

 

[aussieflash]

Re: 150hp tower not getting enough power

First locate manual for your model.It will have procedures and specs for you to follow.Post serial# and carholm might chime in with correct manual.
First you can check that your floats still float and are not saturated or split (if plastic).They cost around $10 and are still available.
Dont guess get a manual.

 

[maagee79]

Re: 150hp tower not getting enough power

I just sat down in the man chair I have the manual in hand going to read for awhile. Tomorrow I with post the ser # I do know its a 1974 1500.

 

[maagee79]

Re: 150hp tower not getting enough power

This is the break down I got

 

[maagee79]

Re: 150hp tower not getting enough power

So I need to make sure 15 is not cracked or sticking and make sure that 17 and 18 are not stuck correct?

 

[maagee79]

Re: 150hp tower not getting enough power

Ok tonight I dug into the carbs. All of the floats were fine the needles were also just fine. I did have this issue my bottom strainer. I took a picture for all of you to see. It seemed like sand in it but not really sure what it was but it was nasty.

 

[Chris1956]

Re: 150hp tower not getting enough power

Check or rebuild the fuel pump. If the diaghram leaks, raw fuel will get into the crankcase, causing the plugs to foul, and you will have great hesitation on acceleration.

 

[maagee79]

Re: 150hp tower not getting enough power

Ok fuel pump is in good order. I took it to the local dealer he said it looked fine. Tonight im going to clean everything with carb cleaner and put it back together. How can I tell if im getting enough spark on all cylinders? Would that be my next point attack?

 

[Chris1956]

Re: 150hp tower not getting enough power

I think you should start an updated thread, or do a complete update on this thread. I do not now know what your symptoms are at this moment. Still leaking fuel? Check your spark plugs for arcing to ground. Clean the distributor cap. The rotor is not removeable, and costs $200 so don't break it.

 

[maagee79]

Re: 150hp tower not getting enough power

Read post #8 after taking it out last weekend its leaking fuel because its either not burning it or its dumping too much in the carbs.