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no power under load idols great

T

tnt2000

New member
I just got an 86 Wellcraft 192 american, with a V6 and a quadrajet 4 barrel carb, thru haul exaust.

Here is the problem. I had run the boat 3 times in the driveway on muffs and it seemed to rune decent idoled good, started a bit hard. The thru haul exaust was a bit load for the wife so I got inline mufflers from cp performance and installed them. ran the boat again on muffs sounded nice. Took the boat to the lake and idled out of the no wake zone
throttled up and had no power would not even plane offand seemed to be smoking, when I let off the throttle it died. Would not restart. opened the hood and there was a lot of gas visible in the carb. Had to get towed in. I assumed flote was not working. I rebuilt the carb this week again ran on muffs idled great started pretty decent took it to the river and same thing, no power. I did not push it and was able to keep it running to get back to the trailer. I am stummped and and not happy with the boat. any ideas.

ps also put new spark plugs.

also how can I tell what enigine is in this boat cant seem to find any markings. I would love to change the cap rotor wires etc but dont know what to get.
http://www.youtube.com/watch?v=pm9f1lJ8YiA
added video of exaust, does all look normal?
 
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List of possible causes of low WOT (Wide Open Throttle) rpm.

In no particular order

Engine Won't Reach Operating RPM. Check

1. Fuel condition. Type and Octane possibly old fuel
2. Propeller pitch or diameter, damaged blades
3. Restricted fuel pickup tube or anti siphon valve Fuel System Test
4. Crankcase oil volume, high oil level can cause aerated oil and lifter collapse
5. Marine growth on hull and outdrive
6. Wrong gear ratio in outdrive
7. Restricted carburetor air intake (clogged flame arrestor)
8. Restricted exhaust system (broken exhaust shutters/flappers) in engine transom shield or drive
9. Poor cylinder compression Compression Test
10. Carburetor defective, or wrong type.
11. Fuel pump pressure and vacuum
12. Boat overloaded, improperly loaded, or improperly trimmed.
13. Engine Overheating
14. Engine timing and ignition system operation
15. Remote control cables and linkage for proper travel to open throttle plates fully.

Above copied nd pasted from another website Don s is the author.

Did not see a motor in the video.
 
I am taking the boat up tonight or tommorrow night to a friends shop and checking as many things on the list as possable. A bit of history on the boat, The carb has been on it for years and It ran good last season I saw a video of it. The owner winterized it and when he went to run this year and change the oil he noticed water in the oil, he put a new gasket set on the motor, heads, intake, and had to send one head out because it had a stuck valve. after that we ran it and got good clean oil and seemed to run nice, just never put it in the water. Now this.. the only change I have made is the mufflers. I let you know how I make out after the checks...

Thanks all TnT2000
 
Awhile back my boat was doing the same thing. Turned out to be a blown head gasket. It had leaked water into the #1 cylinder for so long the piston was shot. The whole motor needed rebuilt. Hope that is not your problem but your symptoms sound the same as mine did.
 
well i am back and very confident we fixed the problem. Turns out the distributer was off 2 teeth, I assume when the other owner did the intake gasket he forgot to set the distributer. we started it it started with about a half crank, I had to turn the idol down it was idoling at 1200 rpm turned it down to 700. unfortunatly here in northeast pa i will have to wait to test it in the water untill the rivers receed. they are all flooding right now. just hope i got the timing right i do not have a manual the engine is a MerCruiser 205 GM 262 V-6 we set the timing to 8 deg. BTDC.
Thanks all for your help I will let you know how she runs when I can put it in the water.
TnT2000


one other question, i would like to put a trim guage on I am use to outbourds and can see it position but i can not see the outdrive. what do I need and where is best place to get it? its an alpha 1 drive

Thanks again
 
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well i am back and very confident we fixed the problem. Turns out the distributer was off 2 teeth, I assume when the other owner did the intake gasket he forgot to set the distributer. we started it it started with about a half crank, I had to turn the idol down it was idoling at 1200 rpm turned it down to 700. unfortunatly here in northeast pa i will have to wait to test it in the water untill the rivers receed. they are all flooding right now. just hope i got the timing right i do not have a manual the engine is a MerCruiser 205 GM 262 V-6 we set the timing to 8 deg. BTDC.
Thanks all for your help I will let you know how she runs when I can put it in the water.
TnT2000

ps does anyone know what i need for a trim guage and where to get it. i hate that i cant see the outdrive
 
well it worked sorta for a short amount of time, I put it in the water got the boat to plane off slowly so the rpms are still not great maybee 300 - 3500, ran up and down the river 2 times and started loosing power to a point that it would only go to about 1500 rpm again. it also started smoking a little at that point, I am lost we set the timing at 8 deg BTDC the person working on the motor with me thought it should be more like 10 deg. would that make a diff. and make it eventually run out of power?

thanks TnT
 
So i sorta guess your gonna have to look at the list one at a time.

My opinion is about the carb it added hp for you a 2 barrel will give you about 30-40 less hp. No it is not to much.

You have thunderbolt ?

If yes everyone who posts here alot will be chuckling to themselves saying here we go again.
 
ok i dont think it is a thunderbolt egnition, but not sure how can you tell? the dist. cap has electronics of some sort on top that the tac plugs into.

my first queston is do i have the timing right at 8 deg BTDC for my motor listed above, did i check it right because the mark that was on the dist. and the intake is off by 1/4 to 1/2 inch. would the timming being slightly off make it load up? i will check the fuel system next but i would like to be sure i have that right.

tnt
 
i dont think it is a thunderbolt egnition, but not sure how can you tell?
Click to expand...

Look on the inside of the port exhaust manifold for a 4"X6" black amplifier module. The wire harness will attach to the distributor. I believe 8 deg. BTDC is correct for that engine when the timing is viewed off of #1 cylinder. Under the distributor rotor is the spark control trigger. The old style trigger is prone to corrosion. You have to remove it to see the underside fine wires. If you find corrosion/rust on it, that can cause a spark problem.
 
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2 cents worth: I had the same problem with an '86 mercruiser 170. The fuel and delivery system checked OK. Points set correctly. Engine timing and dwell good at idle. I removed the distributor cap and found powdery metal filings. I removed the rotor, the plate that holds the points and condenser, and guard which held weights and springs in position. One of the weights was stuck in an outward position and had been scraping against its mounting. I cleaned the metal powder and lightly lubricated every contact point with a toothbrush and hi temperature disc brake grease. Reassembled, sea tested; full power under load at any throttle setting.
 
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