89-50HP Carb doesn't fit on 91-50HP

[Eddie Rivera]

I'm swapping power heads.

-- My original 1989 50 HP model 507X89B carburetor Asbly. part number F628061-3 and carb adapter flange part number FA433167.

-- My replacement head is a 1991 50 HP model 508F91c carburetor Asbly. Part number F718061 and carb adapter flange part number FA691167.

---- Question----
Can I use my 89's carb adapter flange to install on my replacement 91 to be able to use my completely rebuilt carb???


:mad-new:

 

[pnwboat]

Re: 89-50HP Carb doesn't fit on 91-50HP

I see the difference. 1989 uses mechanical choke. 1991 uses a fuel enrichment solenoid. Your 1989 carb should bolt right on the 1991 flange. You just have to unscrew the two screws that hold the choke solenoid assy. on the 1989 motor and move it over to the 1991 motor. I can see the mounting bosses for the mechanical choke on the 1991 motor. Are the holes on the mounting boss on the 1991 motor threaded?

 

[Frank Acampora]

Re: 89-50HP Carb doesn't fit on 91-50HP

The 89 uses a WB carb while the 91 uses a much larger TC carb. While the bore and stroke on both engines is the same, The earlier engine will not be happy using the TC carb.( I don't know why, I tried it and it simply did not work well.)

HOWEVER: The later 1991 engine should run very well using your rebuilt WB carb. The mounting plate or carb adapter flange will bolt directly to the 1991 block and the choke solenoid should bolt directly to the mount below the carb..

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

There is a difference and my 89 carb does not fit on my 91,

 

[Frank Acampora]

Re: 89-50HP Carb doesn't fit on 91-50HP

Yes, BUT the assembly of carb and adapter plate will fit.

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

Got cha Frank, thank you so much. That was my crazy idea that for the first time I may have been right.
I got a close up picture of the 91 carb flange that shows 2 additional bolts right next to the carb holding bolts, what are those? My 89 does not have those 2 bolts, will it matter?

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

Ok frank I see what you mean now. The carb flange should fit right on. I also measured everything too.
- If I change the carb flange must change the gasket too, correct??
Could I make one flange gasket from the gasket rolls they sell at the auto parts store?
I was told I could make my own carb gasket too from those rolls they sell I make a gasket.

Frank, I called the place where I bought the power they're called Northern Lakes Marine, as the owner Mike, awesome generous super guy, said he would look for the carbie that comes with that power head and just sen it to me in a couple of days, and he mentioned that the reed valves may need adjusting or may possibly not work properly.
So what do I do now?
Should I change the flange to use my fully rebuilt carb? Change or make the flange gasket?
Should I just wait for the carbie? Make or buy the carb gasket?

 

[MickLovin]

Re: 89-50HP Carb doesn't fit on 91-50HP

Hi Eddie, Frank Guided me through putting on my TC carbs replacing my wb. You will more than likely need a new gasket for the flange plate, the reeds won't have anything to do with it and don't need to be removed. You can make the gasket, I did with no problems, I also use a smear of gasket goo, only a smear.
If you have carbies coming just wait for them and do a straight change over without the fuss. The TC carbie I used was from a 135hp chrysler, mine was a 100hp. So you know, because of the lack of availability of parts I decided to have a spare gasket kit on hand for my carbies. If you are going to buy 2 kits why not 4 save delivery.
IMO wait for the other carbies to come and save your money and time changing over flange plates, I changed mine but for an increase in hp and as an experiment, you don't need to experiment as you have the same carbie coming and the WB won't improve your performance.

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

I bow my head to you all out of respect and amazement. You are all my masters. I'm much obliged !!

 

[MickLovin]

Re: 89-50HP Carb doesn't fit on 91-50HP

Ah no problems mate the more ya play and work on em, the more ya learn ay, but you need to work/play correctly, you don't want to create problems . So always have a decent manual and good read before you play/work LOL.

 

[pnwboat]

Re: 89-50HP Carb doesn't fit on 91-50HP

One other thing to take into consideration....If the 1991 carburetor does not have a mechanical choke like your original, you will also need one of these. It's the fuel enrichment solenoid.

Solenoid Primer F694924 Force Chrysler 1989 1995 70 150 HP Outboard Motor 732 | eBay

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

Oh man, now i've got to see if it's mechanical or not and how to incorporate this solenoid into my system. Gosh!!! I dream if the day I will actually use my boat. Hahaha - I had to learn all about for a year and a half first I guess. But with you guys in my corner I shall enjoy it soon with my family.

 

[pnwboat]

Re: 89-50HP Carb doesn't fit on 91-50HP

It's pretty easy. I swapped out my original carbs with mechanical choke to the carbs that require the solenoid. You use the same green wire that is used to engage the mechanical choke as you do to engage the solenoid. Then you have to a small 1/4" fuel line from a fitting on the carburetor fuel bowl to the solenoid, then another one from the solenoid to a fitting at the base of the carb. Then you have to mount the solenoid on the motor anywhere close to the carb.

 

[Frank Acampora]

Re: 89-50HP Carb doesn't fit on 91-50HP

Eddie: If the gaskets are still good with no breaks or cuts you can re-use them. The adapter plate gaskets are the same, but, of course, the carb flange gaskets are different. Yes, you can make your own gaskets from 1/32 grey gasket paper sold at Pep Boys and other auto stores.

The carb flange on the TC carbs is so much bigger that the adapter plate bolts would not fit next to it. SO: the TC adapter plate uses longer Allen head screws recessed into the plate so the carb will fit on. When the smaller WB carb adapter plate is used, regular hex head bolts will fit.

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

Thank you Frank, I'll buy some gasket paper rolls to keep in stock for emergencies.
I want to share with everyone part of my learning. I've had major problems with wires getting pinched and the system grounding due to inexperience or lack of attention to small details. I have a picture to show the right and the wrong way to install the cdi/ignition coils pack and braket.
Top pack #1 is the right original way installing the 2 coils in front of the holding bracket giving the wires in the back more room as to avoid pinching.
Bottom pack #2 is my installation and the cause for continuous problems with pinching and shorting.

This small detail has given me many problems and I've read of others here with similar Simpsons so please share them and hope it helps others as I've been helped here as well.

 

[MickLovin]

Re: 89-50HP Carb doesn't fit on 91-50HP

Yea mate not good, that's why a manual is worth it's weight in gold.

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

MickLovin, I'm not sure that small detail is explained in the manual. But again that simple detail has been giving me hell even as I have protected the wires, there was not enough room due the the position of the coil on the bracket and also the spacer used on my motor was missing so a nut was used in its place but again not enough space in the back when installed.

 

[MickLovin]

Re: 89-50HP Carb doesn't fit on 91-50HP

As an electrician, I have seen more burnt, internally broken, pinched wires than you can imagine and I know from experience the stupid intermittent problems which they cause, but you mention a spacer missing, you can't help sometimes what others do.

 

[Eddie Rivera]

Re: 89-50HP Carb doesn't fit on 91-50HP

Exactly right. That's why I want to share this, you all share so much with me I thought I would "pay it forward" and share to help others how I learned about a small detail that gave me so many issues.
I've also ordered the service manual and now own the seloc manual.
So I'm starting to put everything back slowly and paying attention to everything I possibly can, hoping for all to go well on my first start up with my new power head and interchanged parts as I wait for my carbie to arrive I now must properly torque the power head to the spacer plate and that to the lower leg, I think I put too much anti seize cream last time though it was easy to loosen up it scares me how easy I loosened them up too and worry about vibration over time.
So do you guys recommend anti seize in the bolts holding plate to head and head to lower leg? Or some medium/Loctite ???

 

[Jiggz]

Re: 89-50HP Carb doesn't fit on 91-50HP

Good point Eddie in bringing to attention some small details. In addition, with digital camera's almost free in cost except maybe for batteries, I've made it a practice of taking pics of everything I do that I consider to be first time for me before disassembly. And I mean real good pics and many different orientations just to make sure I got it right the first time. Some people even go with video's and even share them over the Net.