Hole Shot Power

[csl]

Deer creek reservoir or griggs. Both less then 30 minutes from home. Where do you go?

Never been to either one of those. Our closest is Eastwood lake near dayton or CJ brown Near Springfield. Neither one is very good so we end up going to kentucky some.

[csl]

AHHH!!!! I'm pulling my hair out on this motor. We put the new prop on and took the boat out friday night. It did seem smoother and cleaner than the old prop, but barely helped the hole shot and didn't gain any rpms. We had three people in the boat. Later we picked up three more and couldn't even get out of the hole unless everyone was in the bow. So i am back to the drawing board after purchasing the prop. I will give a breakdown of everything and hopefully someone can answer some of this.

Here is what the boat is doing: Idles fine and seems to run very smoothly. On the hose, you can't tell anything is wrong. Can rev it up to 5-6000 rpms if you want, so I know the motor can handle it and is running good. When we put it on the water it starts up great, idles great. When starting up, it will occasionally backfire through the carb. When we give it throttle for the hole shot, it just can't build the rpms at all. unless everyone is in the front of the boat it can't hardly do it. Once on plane, it runs real well but it does seem to have a very small miss every now and then. We are also drinking the gas way more than ever before. It also has no top end, RPMs are only getting to about 3,300. and speed only to about 30.

I don't think it is a performance issue, but a fuel or distributor issue. Will welcome all feedback
Here is what has been done so far. Tune up was done a year ago. Last fall the carb was rebuilt by a local carb shop. Timing was reset this spring on the hose, but not under load. New plugs this year also. Just changed the fuel filter tonight and there was some junk in it. Also ruled out the Fuel Pump. Took it loose from the carb and shot it into a jar. It had plenty of power. Ruled out the Power Valve in the carb with the two adjustment screws. Also my carb guy put ball float safetys in during the rebuild. He said all new holley carbs have that and it saves the Power Valve. Not really sure were to go next.

Here are some questions
Will the secondaries open up on the hose, or do you have to be under load? I had to rev it up to 5,500 or more tonight to see any action out of them. May not be a real good test until in water.

Could my carb need attention again so quick?

If it is my distributor, how do I check it. I took the cap off and the rotor is not wobbly at all, but I don't know much about all this. I am not a mechanic at all and have learned most of this from researching this forum!!

The one other thing i can think of, is i know my foam is wet under the floor. I plan on doing a rebuild this winter. But I can't hardly think weight is it, because I've been in too many boats were we loaded the fat sacs and had a boat full of people and still had the power. Also we had an ok hole shot this spring, but something has changed.
Sorry about the rambling, but any thoughts would be awesome. Thanks

[Torque]

Hi,

If the engine backfires thru the carb, you have a timing issue. Could be one of two things, or maybe both. 1) the distributor may have slipped or been bumped accidentally. 2) the timing chain may be stretched or worn out. I'm betting on #1. Put a timing light on it and check it. Is it an electronic ignition system? Or just a points and condenser setup?

[92SupraComp]

If its points and condenser, replace them. Set your timing a 10 degrees before and enjoy. I set my CC to 10 degrees before TDC in summer 2011. Early summer 2012 went up to NH with family and did some skiing. Had 7 people in the boat and 1 skier behind, 8 total. It was a dog getting up but would get the skier up every time. Had 4 people in the back and other 3 up front. Got back to Keuka, found the timing was 1 degree after TDC!!! Set to 10 and good as new! But that indicates Im due for new points and condenser in the CC.

[csl]

First, it is an electronic ignition. Second, I do think I am getting somewhere. Its slow, but progress. After changing fuel filter again and cleaning the screen before the carb, it has a greatly improved hole shot now. I wonder if I have some serious junk in the fuel. We took the boat out and played with timing last night. The sweet spot seems to be advanced 10-12 from top dead center. My rpms still haven't gotten above 3,400 though. How far should timing advance when given full throttle? Also the only time it backfires through the carb is when you give it full throttle quickly. If you ease into it, it doesn't backfire.

On another note, now that I have a hole shot and can board that new prop rocks!! It has really changed my wake from before. Its bigger with much more lip. I am very pleased with the purchase now. The boat feels different at speed also. I do have one question on the prop. At takeoff and occasionally at speed there is a small thump. You can feel it more than hear it. It didn't do that before the new prop, but its not a vibration. Just an occasional bump. Any thoughts?

[dirtydawg]

dont know about the bump noise but dont over rule weight as the performance problem. water logged foam can be very heavy, and if your motor is getting least bit tired it will most definitely be a factor with hole shot. I recently added 700# of ballast and with a new 351 HO, Its noticeable. If I tried that with my old motor or had to many plp. in the boat it would take the length of a football field to plane out. Good luck

[wotan2525]

I disagree about the wet foam. It might prevent you from planing out quickly, but it wouldn't prevent your engine from revving up higher.

[csl]

From researching old posts and what I have learned by playing around with the boat, I wonder if my advance mechanism is acting up. We timed it at an idle on the water to 10 degree. What is the best way to time it? Also, it did advance when given throttle, but not very much. From what im reading, it should advance a good bit. How much? Don't know much about all this, but you all are helping me learn.

[Hagman]

The base timing should be set at around 8 to 10 Degrees before TDC @ 600 rpm . book is 6. Total should be 30 to 34 degrees. . I’m thinking that total timing comes in by about 2000 rpm or less. You can check this easy with a timing light . You should be able to turn the rotor a little by hand and it will spring back. If it doesn’t there is something wrong. You might have some broken springs on the weights under the points plate. Easy Fix.

[csl]

Ok so here seems to be my issue finally (I hope). Took my distributor to a local shop that has a diagnostic machine. When set at 10 degrees BTDC it only advances to 19 degrees. It also takes until 5000 rpm's to get that far. So it is definitely faulty. It is the old Presolite and he recommended just buying a new one. This one is old and wore out and can't get parts for anymore. So my question is what do you all recommend to replace it with? I know skidim has the Mallory distributors, but is that the best one to get? Also best technique on convince my wife I need to spend more money on the boat. Ha Ha