1972 evinrude 9.5 Carb problems?

[Bransonspiers]

Hey guys, first time poster, I have seen some great advice dished out here, I don't know where else to turn.
I recently purchased a 1972 Evinrude 9.5 Sportwin outboard from a buddy, it was his grandfathers and had set up for the last 12 years without being ran. It cranked up immediately for me but had a tendency to bog when I gave it throttle and then just to quit and not want to crank for about 30 minutes. I replaced the plugs with NGKs, got a new gas tank, blew out the fuel filter screen, and purchased a carb rebuild kit. I installed the rebuild kit to the best of my ability.....blew out the ports, soaked it in carb cleaner, replaced all of the parts that were applicable in the kit. I took it out and here is what it is doing now...... It cranks right up no problem and even idles pretty well. When I try to get it on step though it bogs and then will rev slightly then bog then rev slightly and bog and so on and so on. It won't get on plane. I don't know if this is enough info for a diagnostic but I would certainly appreciate any help in the matter. I look forward to any advice. Also, not sure I know exactly what to turn the fuel mixture dial to? I have played with it a little but it doesn't seem to make that much of a difference.

 

[tashasdaddy]

Re: 1972 evinrude 9.5 Carb problems?

Welcome to iboats. you have a fixed high speed jet, behind the drain plug of the carb bowl. did you take it out and clean it. details here, http://forums.iboats.com/showthread.php?t=244013

carb adjustment:
(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

also is the vent open on the fuel tank? if this does not cure it. try pumping the primer bulb of the fuel line, it that cures it, you have a weak fuel pump, or leak in fuel line.

it would also be advisable to change all rubber lines to alcohol resistant lines, due to ethanol in the fuel.

 

[fireman57]

Re: 1972 evinrude 9.5 Carb problems?

First of all, welcome to iboats. Sounds like you have everything right so far. When it starts to bog, squeeze the primer bulb and see if it picks up rpms and speed. If it does then you need to replace the fuel pump. Easy procedure. Good luck and keep everyone posted on the progress.

 

[fireman57]

Re: 1972 evinrude 9.5 Carb problems?

Dang, tdaddy beat me again. I don't know whether to blame my dialup or my slow typing.

 

[Bransonspiers]

Re: 1972 evinrude 9.5 Carb problems?

Thanks for all of the quick response guys. I did in fact, pump the bulb while motoring and that did not help.

 

[fireman57]

Re: 1972 evinrude 9.5 Carb problems?

Looks like your tearing your carbs apart again like tdaddy says.

 

[Bransonspiers]

Re: 1972 evinrude 9.5 Carb problems?

Tashasdaddy, thanks for the informative reply. I dont recall removing that high speed jet. Could that lead to my problems? 1. What does it look like? The carb on my motor looks a little different than the one in the link. There are two small diameter aluminum "caps" that cover some sort of orifice on the carb and the rebuild kit did come with replacement caps. 2. Are the high speed and low speed behind those caps. 3. What are the procedures for finding the correct lean/ rich mixture?
Thanks for the help

 

[ezeke]

Re: 1972 evinrude 9.5 Carb problems?

The high speed jet lies horizontally, directly behind the drain screw in the float bowl (circled in the picture).

Because it is located where it is, it picks up any debris that sinks to the bottom of the carburetor as well as the gel that forms when the gasoline in pre-mixed fuel evaporates.

 

[Bransonspiers]

Re: 1972 evinrude 9.5 Carb problems?

Thanks, thats the exact carb that I have. I am going to give that a shot. Any thought on the lean/rich fuel mixture dial? I am not sure I know the procedure having never owned a motor with that on it. Thanks for all of the help!

 

[tx1961whaler]

Re: 1972 evinrude 9.5 Carb problems?

For the idle adjustment, see the earlier response by TD. Initial setting is 1.5 turns out.

 

[Bransonspiers]

Re: 1972 evinrude 9.5 Carb problems?

Alright, in regards to the thread above. First off, I removed the high speed jet and cleaned the orifice (it looked like it was in good shape) i also blw out the orifice with comprssed air and carb cleaner.
I took the boat out again and here is the problem I am having. It cranks right up, idles fine and ititally (first 30seconds or so) revs just like it should. Then it starts to bog and the rev bog and then rev, it runs a little more consistent at half throttle. I have tried pumping the bulb while motoring but that doesn't help. Any chance it is still the fuel pump/diaphram? Could it be electrical? Any suggestions??? Thanks in advance.

 

[ezeke]

Re: 1972 evinrude 9.5 Carb problems?

That's usually caused by a air leak somewhere in the system if you have the lean/rich set correctly.

Be sure that the hoses are clamped tight and that the gaskets are good.

There are three lead shot seals on the main carburetor body that need to be in place.

Also check that the gasket between the fuel pump and the engine is air tight.

When you pump the primer bulb it fills the float bowl, then the fuel pump refills the bowl as needed. The fuel is pulled into and through the carburetor by the vacuum created by the pistons. It does not hold that you could empty the float bowl in 30 seconds, so it is unlikely that the fuel pump is the problem unless it is the source of an air leak.

You can tell if you are running lean by pulling the choke out a little after the engine warms up; If the speed picks up with the choke, the lean /rich setting is probably too lean.

 

[Bransonspiers]

Re: 1972 evinrude 9.5 Carb problems?

Thanks Ezeke,
Ill chase that lead and go through my hoses and gaskets to make sure they are in porper shape. In regards to the lean/rich mixture comment you made. I don't see any noticeable difference in the engine whatsoever when I play the the lean/rich mixture dial. I also noticed when I took the needle out of the lean/rich orifice that it was pitted or slightly worn right at the tip. Could that contribute to the problem?

 

[ezeke]

Re: 1972 evinrude 9.5 Carb problems?

Yes, it's possible.

 

[Rick.]

Re: 1972 evinrude 9.5 Carb problems?

If you can adjust the lean/rich without any affect on the motor then I would guess you need to do some more carb. cleaning. You should notice a change when it's being turned. Rick.

 

[1972EVINRUDE9.5]

Re: 1972 evinrude 9.5 Carb problems?

I am having a problem with my 1972 evinrude 9.5 sportwinn it starts and stays running just fine. I can't get the motor to rev up or use all of it's potential unless I take the cover off the motor? Then the engine seem to take more air in and will rev up to full speed. I spoke with buds marine and they stated that the power head may need a new seal. haves anyone ever experienced this? and what should I do to fix the problem?

 

[tx1961whaler]

Re: 1972 evinrude 9.5 Carb problems?

Yes, that exhaust leak is quite common with the 9.5.
I believe that you must pull the powerhead and put a new base gasket in to correct the issue. It's not hard to do.
Also, next time post a new thread instead of tacking on to an old one and you'll get more responses

 

[ezeke]

Re: 1972 evinrude 9.5 Carb problems?

The 9.5 has several possible exhaust leaks, plus it can inhale exhaust if running in a bucket even with all seals good.

The areas to check are the exhaust relief hose at the back of the engine, the exhaust housing seal shown on the lower unit group diagram, the shift rod boot, and the drive shaft seal above the waterpump.

 

[1972EVINRUDE9.5]

Re: 1972 evinrude 9.5 Carb problems?

ok thanks for the images I don't understand what you mean by pulling the powerhead how do you pull the powerhead? I appreciate the advice guys thanks

 

[kbarfoot]

Re: 1972 evinrude 9.5 Carb problems?

I am a newbie to this site. I have a 1972 evinrude 9.5 and rebuilt the carbs. I took the fuel pump apart. There is a diaphragm inside the fuel pump assy.
(looks like it probably pulsates and pushes fuel). It looks pretty old and needs to be replaced. The place I bought the carb rebuild kit says you can't buy a rebuild kit or this diaphragm. They advise buying the fuel pump assembly for $100. Anyone have any ideas on where to buy this?