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"OK, I pulled the boat out and

"OK, I pulled the boat out and power washed the OD and bottom. Now it doesn't over heat which is a good thing. But, it will not rev properly. I had a 14.5X 21 prop and the engine would only turn 2000 RPMs and then seem to bog down. We put a less pitched prop on and now it turns 2700 RPMs and then bogs down. The mechanic (supposed to be the best in Baltimore) showed up this morning and checked timing and timing advance and everything is good. The bottom line is he did not know or have any idea why it will not rev up. The mechanic said it idles perfectly and gas is not a problem. If anyone has an idea please post it. Thank you, Bob PS- Prior to all these problems, it would get up and plane with the 21 pitch prop without any problem."
 
"I hooked up my tachometer

"I hooked up my tachometer and the voltmeter dropped from 14 volts to 13 volts."

Disconnect it and see if the engine will run better.
 
"Here is where I am. Replaced

"Here is where I am. Replaced the ignition wires today and coil but no help. I disconnected the tach. but no help. So far I replaced everything in the dist (pick up sensor, cap and rotor). I checked the timing and it is at 8* and 30* when advanced. I replaced the ignition module on the exhaust manifold. It idles very smooth but a little slow (600 in gear)but never stalls between shifts. I replaced the spark plugs and gapped them at .035. There isn't much more can be replaced. How about the fuel, could it have a reduced combustion point (stale)? Or since it idles smooth then will not rev above 2700 rpms could a filter be dirty? It could be partially clogged and allow enough gas through to idle but not enough gas when I dump the throttle? Also you can hear the secondary barrels opening up when I put the throttle down the entire way. All suggestions are welcome. Thank you, Bob"
 
"if you have a 4bbl Quadra Jet

"if you have a 4bbl Quadra Jet (big secondary butterflys) the secondary the idle circuit could be lean which would cause the issue you are seeing.

the idle circuit typically goes to about 1500-1800 rpms. I had an issue with a Webber Style (like the Edelbrock carbs) that the secondary metering jets rod springs were wrong from the factory Sierra (reman) I found this out by applying some choke by hand when it got to that range and found the engine IMPROVED power with choke.. a clear sign it's lean, if it' worsens, it's RICH enough..

About the gas question, yes, stale gas or gas that has some water in it will reduce your power. put a fuel sample direct from the fuel tank into a glass jar and have a look.. let it sit for a few minutes to about an hour. If you see a line or "bubbles" at the bottom, that's water.

But I would think it wouldn't idle to good either."
 
"Since you have fixed everythi

"Since you have fixed everything to-date; the only thing left is the carb. If it is the original carb that has been rebuilt time and again over the past 21 years, get a newer reman. Merc. carb via www.ebasicpower.com or send it out to an independent reman. business. I know of one that charges about $250 exchange."
 
"If you have a canister fuel f

"If you have a canister fuel filter, put on a new one full of SeaFoam and run the engine at idle for 5 mins. Let it sit o'night and dump the fuel out of the filter and fill it again w/SF and repeat. Then take it out and run the crap out of it. If it doesn't work; new carb time."
 
"Brian & Guy, Thanks for t

"Brian & Guy, Thanks for the quick responses. I know that a mechanic did pull a peice of the linkage off the carb that went to the choke. He said a boat runs better without the choke. The carb is 8 yrs old and a GM quadrojet carb. I had it rebuilt and cleaned the winter before last and hardly ran my boat because of this condition last year. The gas I put in is all normal gas (NO Ethanol). I haul it from Pa. to Balt. just to stay away from the ethanol. Last winter the boat was stored with 1/2 tank of gas and Stable or Startron put into the tank to stabalize the gas. I'll get some from the water/fuel seperator (it looks like an oil filter)and see how it looks. Also, is that what you mean Guy? Should I fill it with Seafoam? and also, what kind of Seafoam ? I never heard of it before this. I'll also check the fuel filter that is where the gas line goes into the side of the carb. Thank you again men, Bob"
 
"Hey another quick question, w

"Hey another quick question, when I'm getting the Seafoam should I get some type of gas treatment to dump into the tank to add combustibility and treat any water inside the tank? If so what kind ? Many thanks, Bob"
 
Bob:

Do you have that linka

Bob:

Do you have that linkage part the brain surgeon removed for you? I would put it back.

SeaFoam is available at most autoparts stores. There is only one type. Don't add fuel octane enhancers to the gas; they will foul the plugs quickly. If you find water in the fuel canister then add 1 can of SeaFoam to the fuel for each 10 gal. of gas; it will remove it.
 
We should start an award compe

We should start an award competition on this website... for the stupidest lame excuse used by a "mechanic" for what they did or want to do.

I'm open to suggestions as to the name of this award... it should pass censors... My suggestion is the "LAFEX Award" For... "LAmestF******EXcuse" award.

My nominee for this award..."He said a boat runs better without the choke".
 
That's a good one. I like

That's a good one. I like the SFB Award.

S..t For Brains Award

Stupid F...'n Bas...d Award
 
"Hey all, This was the shop ma

"Hey all, This was the shop manager of the major boat dealer, part sales and marina located in Balt., Md. I said to him "what are you doing" and he replied "disconnecting your choke, a boat runs better without a choke". "I'm the shop manager so listen to me". I didn't like it at the time and still don't like it. A carb is engineered by smart people and little fingers should not be messing with it. Anyway, it's been done so hopefully I can fix their mistakes. Thanks again, Bob"
 
"Bob

Send me his name and p

"Bob

Send me his name and phone number and I will call him

Also by doing what he did he made your boat unsafe to operate and therefor assumed ownership of it if anything went wrong!

If your boat was running at speed and you had to pull back on the throttle to avoind running over someone (god forbid) and because the choke was removed and the engine did not slow down as fast as normal or died and you lost steering control, it would have been his responibility!!"
 
Also you may want to contact w

Also you may want to contact what ever agency or even a local newspaper with this info!!
 
"the Choke closes when the eng

"the Choke closes when the engine choke stove or electic coil closes the choke, once it warms, the choke should not be closed until the engine cools again.

The choke wont interfere with the throttle plates closing, connected or not (unless some not so smart person connected in such way-improperly)

Bob, even if you live in Florida, the choke should be closed for initial startup then should open fully after about 1-2 mins, up here in the north it can stay longer closer, there is a post here somewhere that says to adjust the choke so that it leaves about an 1/8" gap, I like to set it to "very lightly" closes.

ps.. recommend you dont go back there for maintenance if you can help it."
 
I meant to say in my rant &#34

I meant to say in my rant "if the choke (linkage) was removed or disconnected"

The choke could close at will depending on how it was disconnected.

No matter what it was wrong and in my opinion illeagle
 
"Theoretically if you were in

"Theoretically if you were in lets say the Panama Canal zone, you could remove the choke. But to do this to get ANY benefit, you would have to completely remove the choke plate. However to be honest, I don't think you could see the difference in carb air flow in performance at any operating point other than Wide Open Throttle, and it would be so slight that you would have to have the engine on a dyno to see it.

BTW... I once had a marine engine that had a manual choke. And the boat manufacturer decided to save a few dollars and not connect it to anything, i.e., choke was always wide open.
Let me tell you , starting that engine when cold, even on a hot day was...a PAIN. I eventually installed a cable and a manual choke control.

Would I be too cynical to point out that a soon as the weather cooled off, you'd be bringing the boat back to the shop for "hard starting" problems when cold. Let me see... "A full tune up should fix that for you sir, let me get one of my men on it right now."

Then after that... "What do you mean it's still hard to start??? it started OK here in the shop!!! You probably need a rebuilt carb.""
 
"ok, here is what I found. I p

"ok, here is what I found. I put a new 10 micron fuel/water filter on and poured the contents of the old filter into a jar. I left it sit and NO water in the gas from the filter. I did as Guy suggested and ran the engine for 5 minutes Sat. night with Sea foam in the new filter and left it sit till Sun morning. When I turned the key it actually started a fraction of a second faster than before. I left it idle for 5 minutes and again left it sit for 2 or 3 hours. I started it again and what was very noticable was the throttle position. It was where I would normally push it for 1,000 rpms but now it was reving at 3300 rpms and sounded alot stronger. My thinking is stale fuel since adding the Seafoam to the filter where it mixes with the gas is giving me higher rpms. It improved the combustion point of the fuel. The tank is down to 25 gallons of the old fuel so I will add another 25 gallons or more of fresh gas and see if the rpm situation is cured. What do you men think? Does that make sense? Thank you again, Bob"
 
I would add Stabil w/25 gal. o

I would add Stabil w/25 gal. of 93 octane to pep up the old fuel. Always add Stabil to the fuel if you won't empty the tank w/in 60 days.
 
"Guy, I'll do as you say.

"Guy, I'll do as you say. I just hope this solves all the headaches. Thanks again for everyones help and advice, Bob"
 
"Bob:

If you have any SeaFo

"Bob:

If you have any SeaFoam left, fill the filter and run it 5 mins. again. My brother adds SeaFoam to his tank w/each fillup; 1 can per 10 gals. of gas. Never has a fuel problem. His boat stays in the water year round."
 
"No problem, I have a can of S

"No problem, I have a can of Seafoam left I can put in the filter. I bought a bottle of Stabile today to mix with my gas. I guess adding both won't hurt any. I just hope this solves my problems. I'll keep you all posted. Thank you, Bob"
 
"Well I was at the boat for 3

"Well I was at the boat for 3 days. I added Seafoam and Stabil and the engine does start alot easier and faster. It will not rev up over 2800 rpms therefore it does not get on plane. Another problem is it overheats again. When running at or above 2000 rpms it is ok but when I come into the dock and am ideling along in gear it does overheat. Should I just put a less pitched prop on to help attain higher rpms and possibly help keep the temp down? Everything is new except for the circulating pump. Should I try a new one? Also, my outdrive does not have a window screen on each side at the water intake so I was unable to power wash inside the outdrive "housing". I think this is where the buildup is thats making it overheat. Thank you, Bob"
 
Is the pump belt tight? Barna

Is the pump belt tight? Barnacles may have taken up residence again or the impeller may be damaged again. What pitch prop are you running?
 
"Bob, I don't have any rep

"Bob, I don't have any repair info to add but Boy, I am tired after reading all that you have gone through trying to fix these issues. Some really great help here from everyone. Makes a fella want to get an innertube and paddle with his arms. HA!"
 
"Guy, The belt is tight and th

"Guy, The belt is tight and the engine overheats when I'm at low rpms. The only thing not replaced is the circulating pump which was moving lots of water when I checked it. I have access to a pump from the parts boat. Should I put one on and see if there is a difference?

The prop is for top end at 14.5 X 21, a 3 blade aluminum. This was max because it would take a while to plane. I put a 4 blade aluminum power prop at 19 pitch on and picked up about 800 rpms at wot. This is what is on now and gives me 2800rpms at about 2/3rds of open throttle. Past that and it won't climb it just hangs there. I know the throttle cable is set up correctly because it will make more noise as I give it more throttle. (it getting more gas but just is hanging there.) The books call for a 15.5 X 15, 3 blade aluminum prop from the factory which I thought was too low at the time.(it would plane at 3600 rpms and about 18 mph at top end.)I have a 15 X 13 SS prop I could put on but that was too low as I could over rev the engine easily with that. I'll drop down to a 15 or 17 pitch but the main concern is the temp.
Robert S.- One thing about owning a boat is it will teach you patience.}
Thank you all again, Bob"
 
"Bob: Let's not give up h

"Bob: Let's not give up here. The circ. pump has an SS impeller; it either pumps water or the bearing fails or seal fails. Pull it off and look at the block circulation holes for crud blocking or reducing water flow. If the pump shaft rocks side-to-side or the weep hole on the bottom is plugged w/corrosion; replace it.

If you put in a 160 deg. F. T'stat, that's for FWC and yours is RWC which calls for the following: PN: 807252T1 T'stat 140 deg.F.
Put it in.

Go back to the original prop and see what the WOT is on the tach; no more than 4800 RPMs. If it gets close to 4000 RPMS then try the SS prop.

Check your OD oil level.

Have you done a compression test yet?"
 
"Guy, The therm. I put in is a

"Guy, The therm. I put in is a 140 degree but I'm unsure of the part number. I'll go to the boat Tues. and pull off the circ. pump and look for gum in the water holes and play in the shaft. Can I pull the incoming water hose off the OD where it comes through the transum and run a "snake" through there to clean out the inside of the OD where I could not pressure wash thru the water intakes? How about if I pull one end off some of the hoses and snake thru them looking for partial blockage. No, I didn't check the compression yet and yes, I think a move to the recommended prop is inorder here. Oh, can I get by reusing the water pump gasket? Thank you for your help and time, Bob"
 
"If the gasket comes off in on

"If the gasket comes off in one piece, flip it over since the cooling is not closed and pressurized. Push a garden hose in one hole and see what comes out the other.

Using a snake; if you break any barnacles loose they may get into the impeller. Use the snake like a finger to feel for blockages in the water hose coupler on the gimbal. If they are there then remove one end of the water inlet hose between the gimbal and the OD and snake it back and forth; flush the passage."
 
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