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Moody Blu'
08-31-2005, 07:50 PM
2 weeks ago I dipped the boat in the water at the ramp. went out to meet up with some friends at tyces shoal. right when i got on plane the boat was real sluggish, definately down on power. I got off plane and checked my distributor connection because it sounded like it was running on 7 cylinders. everything was fine. It just went away. One of my spark plug wires on cyl #5 had a burn on it but it was like that for the whole season. the new headers were the culprit and i had to re-route the wires in the begining of the season. so the wire was burnt a bt all season but it ran like a champ, 4500 rpms all day and night and if you slammed the throttle from 1/2 to WOT the boat would just jump.

Last weekend I launched it and there was the problem, this time it didnt go away. I checked all my connections distributor, spark plug wires etc. I even changed the wire with a different wire and it did the same thing. I cleaned the distributor cap and rotor as well. I also took the carb apart to check for debris but it was clean. Now when i go to get on plane the boat is very sluggish and if i slam the throttle from 1/2 to WOT i get a pop and then it accelerates very slowly but it only gets up to about 4100-4200 rpms. I checked my plugs and they are all fine. when i took the carb aaprt i went up 2 stages rich on the secondaries since the plugs were a little to lean for my liking. the boat acted the same way with a little less pop from 1/2 to WOT.

could my fuel filter be starving my carb? did i stick a valve?
Bad coil? bad ignition? Maybe a bad dist cap? bad fuel pump?

Its funny, it ran fine 2 weeks before except for the hiccup in the begining of the day.

any help, advice would be appreciated. I am calling up summit racing to buy some new ford racing wires to start fresh.

im hoping its the spark plug wire. the one i tested with was the type of wire that plugs into the distributor cap. its the opposite of the type of cap i have, the type that has a spark plug type connection. would that make any difference?

Trueser
08-31-2005, 08:54 PM
Did you check to see if the water separator was full of water?

Moody Blu'
08-31-2005, 09:01 PM
Did you check to see if the water separator was full of water?


I will check that as well. I just ordered a new cap and new wires from summit, next day air. the cap and rotor are 4 years old and were carboned up a bit but i cleaned them, but i like to start fresh every once in a while. the wires are a year old and i usually buy new ones every year. so theyll be new for next year. aside form all the other projects i have in store for the boat.

onesubdrvr
08-31-2005, 09:02 PM
A couple of other things to check would be spark plugs and timing, have you seen any (even slight) differences in running temp?


Wayne

Moody Blu'
08-31-2005, 09:08 PM
A couple of other things to check would be spark plugs and timing, have you seen any (even slight) differences in running temp?


Wayne
i checked the plugs there fine, the timing has been dead on for 4 years. I doubt its the timing it starts up right away like usual its just not firing on all 8. theres no water in my oil or blue smoke out the back.

boatnut
08-31-2005, 09:58 PM
Could there be some debris in the leaf blower?? :biggrin.: Ed

boatnut
08-31-2005, 10:12 PM
Improper timing advance will also cause your symptom. Timing is ok for starting but doesn't advance properly at high rpm. You probably have mechancal advance (rather than vacuum) so check to be sure advance plate, weights, springs etc. are free and not corroded in the distributor. You can put a timing light on the engine and rev engine to see advance action.
I think changing the plug wires is a good first step.
Ed

Moody Blu'
08-31-2005, 10:18 PM
Improper timing advance will also cause your symptom. Timing is ok for starting but doesn't advance properly at high rpm. You probably have mechancal advance (rather than vacuum) so check to be sure advance plate, weights, springs etc. are free and not corroded in the distributor. You can put a timing light on the engine and rev engine to see advance action.
I think changing the plug wires is a good first step.
Ed

you know this sounds like a good one. yea it is mechanical advance and that coudl be the problem but it does it at idle as well you can tell the sound is just a bit off everywhere in the rpm range. it could be the mech advance though maybe the springs are disconnected or some sort of problem. I will def be checking that. i ordered a new cap and rotor so when i switch the rotor ill know for sure.

I have a twin leaf blower set up but I still have to figure out the throttle linkage for them :bonk:

boatnut
08-31-2005, 10:57 PM
you know this sounds like a good one. yea it is mechanical advance and that coudl be the problem but it does it at idle as well you can tell the sound is just a bit off everywhere in the rpm range. it could be the mech advance though maybe the springs are disconnected or some sort of problem. I will def be checking that. i ordered a new cap and rotor so when i switch the rotor ill know for sure.

If you haven't visually inspected the advance mechanism in awhile I would take the dist apart and check it out -- it likely is corroded. When the engine starts you get advance right away so if it isn't advancing at all it will effect the operation and throttle response throughout the entire rpm range. The best fix if that is the problem is to have someone put the distributor on a distributor machine and check out and calibrate the entire advance curve. Most performance oriented shops do this. However if it is corroded and you free up the weights and be sure the plate can rotate etc. you will notice an instant improvment. These things frequently are intermittent at first which is what you had happen in the past. Seems real logical so it probably is something else. Good luck

Moody Blu'
08-31-2005, 11:35 PM
I dont think theres a need to calibrate my advance, the motor runs great the way i have it set up, i played with the different bushings for the mechanical advance as well as the springs. I went with the smallest bushing and lightest spring so it advances the fastest and i tried all sorts of combinations when i set up the motor and this set up had the most torque and highest rpm. I am not sure if its the mech advance because it doesnt run good anywhere in the powerband, even at constant rpm I can hear a miss.
im hoping its the wires.

blackhawk
09-01-2005, 11:07 AM
Check your power and ground battery cables while you're at it. A friend of mine chased his tail checking all kinds of things for 3 weeks when his boat was only running 4500 rpm and ended up being a bad power cable! :banghead:

Carl C
09-01-2005, 11:19 AM
You should check the compression before throwing a bunch of new parts on it.

mrfixxall
09-06-2005, 04:48 PM
broken rocker?will make no noise,,,broken intake rocker will make your plugs look good......

DonziMon
12-29-2005, 07:53 PM
Hey Broque,

I was just getting ready to list my 22 for sale when it started doing exactly the same thing as yours. So far I've only ran it twice with this problem and it hasn't gotten any worse, yet. Basically, it starts the first time, has a slightly rough idle, bogs during holeshot but runs like the devil at WOT. I had someone tune up the boat for the upcoming sale but I ended up redoing it all myself for trouble-shooting (plugs look real good). I was getting ready to jump into the carb (possibly a sticking needle valve causing some low rpm flooding?) but then I found your post. A slightly erratic gauge problem popped up at about the same time so I'm going to look at the battery cables, as suggested.

So, what was your final fix?

hardcrab
12-29-2005, 07:58 PM
i read somewhere that spark plug wires should test good at 8000 ohms per foot resistance

Moody Blu'
12-29-2005, 08:05 PM
Hey Broque,
I was just getting ready to list my 22 for sale when it started doing exactly the same thing as yours. So far I've only ran it twice with this problem and it hasn't gotten any worse, yet. Basically, it starts the first time, has a slightly rough idle, bogs during holeshot but runs like the devil at WOT. I had someone tune up the boat for the upcoming sale but I ended up redoing it all myself for trouble-shooting (plugs look real good). I was getting ready to jump into the carb (possibly a sticking needle valve causing some low rpm flooding?) but then I found your post. A slightly erratic gauge problem popped up at about the same time so I'm going to look at the battery cables, as suggested.
So, what was your final fix?

well i never actually ran it after i put in the new cap/rotor and wires so im not sure if if fixed it yet lol.

it could possibly be my ground though ill have to check that out in spring. I need to change my tank though.

DonziMon
12-29-2005, 08:20 PM
Tank? I don't envy you for that at all. I guess the dang weather has gotten in the way for both of us, me 'cause I'm in Hurricane Alley, which I'm glad is over, and you for all the Northern stuff. But let's keep each other posted ;)

BTW, when I was a kid we used to vacation at the Sea Splash Motel on Long Beach Island, just a few blocks south of the lighthouse. But that was long ago and now I live at another crowded touristy beach "resort" :D

MOP
12-29-2005, 08:53 PM
DonziMon I see you are from Niceville, that place brings back a ton of fond memories I was stationed at Eglin and lived in Niceville/Valperiso. That was back in 59-61, I can just imagine how it has built up by now.

Phil