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switching carbs question1985 140

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starsh1p

Regular Contributor
Hello, I have what I believe is a 1985 mercruiser 140 engine seriel# B403574.
the carb on the engine has a tag# of 1389-9350
I have a newer carb from what i think was a 1985 Mercruiser 140, the carb does not have a tag on it but stamped on the side of the carb are these numbers 15396A-4 and directly under that number is 2701.
My questions are,
1. Can I use this newer carb in place of the older one?
2. is this sierra rebuild kit the correct kit for both carbs? Sierra# 18-7746
says on box: for 2 bbl rochester carburetors replaces mercruiser 823427A1

Thanks
 
Re: switching carbs question

sorry i meant the second carb is from a 1995 mercruiser 140, the age difference is why i am wondering if they are interchangable. they look exactly alike
 
Re: switching carbs question

one adjustment screw it's a mc'carb and will fit. A omc rochester will need a adapter plate. It has 2 adjustment screws.

1995 doesn't have a 140 it's a 3.0 just 10 hp difference.

I have the 85' merc motor 140 in my boat but i run a omc mani and rochester off my 2.5.

Yes same rebuild kit.
 
Re: switching carbs question

starsh1p said:
Hello, I have what I believe is a 1985 mercruiser 140 engine seriel# B403574.
the carb on the engine has a tag# of 1389-9350
I have a newer carb from what i think was a 1985 Mercruiser 140, the carb does not have a tag on it but stamped on the side of the carb are these numbers 15396A-4 and directly under that number is 2701.
My questions are,
1. Can I use this newer carb in place of the older one?
2. is this sierra rebuild kit the correct kit for both carbs? Sierra# 18-7746
says on box: for 2 bbl rochester carburetors replaces mercruiser 823427A1

Thanks
Click to expand...
Just so that you are aware, The part number 823427A1 you are about to buy is for the rochester carb only.

The part number for a mercarb gasket set is old part number 9061 that has now superseded to 810929004.

By the way your engine is considered a 1986 MERCRUISER 140, Model number 01402006, Here's a link to your engine parts for you.
http://www.mercruiserparts.com/selectSerailRange.asp?doc_nbr=140+++++GM+181+I%2FL4++1982%2D1986

Your mercruiser service manual part number for your 1986 engine is 90-14693, otherwise known as service manual #10.

If your other carb is really off a 1995 engine, then here would be the parts for it.
http://www.mercruiserparts.com/selectSerailRange.asp?doc_nbr=3.0LX+++GM+181+I/L4++1990-1995

Also the 1995 carb would have been a mercarb only according to the 1995 parts diagram above, So the gasket set for for the 1995 carb is going to be old part number 9061 that has now superseded to 810929004 from Mercruiser.

Do you by chance have the serial number off the "1995" engine just to be sure? I ask that Because the 2701 number is the date code of the carb. So going by the 2701 number, That means this carb was made on july 1 1992.;)

Also your carb number (15396A-4) is missing one number and it looks like it should have been an (8) making this the carb part number 815396A4. This number fit's a 3.0L mercarb 43MM according to Mercruiser service manual #13 GM 4 CYLINDER.

The 1389-9350 is the part number to a mercarb that goes a MCM 120/140 2.5 /3.0L engine according to Mercruiser service manual number #10.

Your best bet might be to find both service manuals #'s 10 & 13 free online;) to study the difference in specifications between the two carbs, That is if that would make you feel better about doing this swap over, I forgot to do that while looking all this up for you.:p

Good luck with it.:)
 
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Wow Boat-tech thank you for all this great information. I have 3 carbs for my engine and they all need to be rebuilt. I just thought that I would use the newer one. I do have the original one off my engine and I think that since I am a novice at rebuilding I should keep it simple and use the one that came with my engine.
Looking at the carb that is stamped 15396a-4 that you say should have an 8 at the front of it, there is no 8 and the stamp is clear and does not seem to be missing any numbers. The seriel number of the engine that it came off of is 0F069636 I also have this motor but it sat with salt water in it for awhile so I decided not to use it because I do not have a starter for it and so I cannot get it running to see what kind of condition it is in. The engine I am using, the one that is seriel #B403574 at least has not been sitting filled with water and I have had it running on a hose, and compression checked and the results were decent. (boat hasn't made it into the water yet, totaling rebuilding it and almost done).
I also have the original carb that was on the boat when I got it but the motor was junk so I am scrapping that motor but still have the carb. it's seriel number is 1389-8490 it's to dark outside rite now to get the engine seriel number but if you have any reason for wanting to know what it is I can get it for ya.
By the way I have all the manuals that were online, not just mine all of them just because it seemed like a good thing to do :)

So in closing :
The engine I am using is seriel#B403574, I will use it's original carb which is seriel# 1389-9350
I think it's best that I dont swap just to keep it simple.
The other two carbs I will hold onto just because I have them I guess, if anybody needs one let me know I will probly be able to part with them because I just dont have the room to store a bunch of stuff. The engines I am not using I thought I would probly disassemble and save some parts or sell them off because again no room for storage so anyone reading this keep in mind that I have them if you need them. This forum has been good to me and I am willing to help if I can.

So I already purchased the rebuild kit that replaces 823427A1 this is the kit for the carb I am using, correct? Did you say that I also need a gasket set?
One last question, I know I have to soak the carb for a cpl days, what is the best solution to soak it in?
Oh yeah and if anybody has a link to a step by step rebuild process or any important tips I should know it would be greatly appreciated. Thanks to all of you for your help, past and present and thank you Boat-Tech for your great information.
 
starsh1p said:
Looking at the carb that is stamped 15396a-4 that you say should have an 8 at the front of it, there is no 8 and the stamp is clear and does not seem to be missing any numbers.

The missing 8 was what was shown in the service manual to help me compleat the number so that the number would come up in the merc parts system as a valid working part number with a match to the carb.
Click to expand...
The seriel number of the engine that it came off of is 0F069636

This serial number shows this engine to be a 1993M MERCRUISER WPS-TWOPCEX-W/O REM-EST IGN 3.0L ALPHA, Model number 430B1003S. You'll use service manual #13 with this engine.
Click to expand...
Just in case you ever need it, Here's a link to the engine parts for engine serial number 0F069636 for you.
http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=816323+90


I also have the original carb that was on the boat when I got it but the motor was junk so I am scrapping that motor but still have the carb. it's seriel number is 1389-8490 it's to dark outside rite now to get the engine seriel number but if you have any reason for wanting to know what it is I can get it for ya.

Nope, I really don't need this engine serial number, That is unless you would like to know anything about this engine?
Click to expand...
With the carb part number 1389-8490, you should be able to find some info about it in the service manual that goes with the serial number of the engine it came off of if needed. But using that part number, i can say it's for a 120/140 model engine.


So in closing :
The engine I am using is seriel#B403574, I will use it's original carb which is seriel# 1389-9350
I think it's best that I dont swap just to keep it simple.

I agree.
Click to expand...
So I already purchased the rebuild kit that replaces 823427A1 this is the kit for the carb I am using, correct?

No, This part number only looks like it will work on a rochester carb only, That is why I mentioned earlier, (The part number 823427A1 you are about to buy is for the rochester carb only.)
Click to expand...
The carb part number 1389-9350 you have comes up as a mercarb, that goes to a MCM 120/140 2.5 /3.0L engine according to Mercruiser service manual number #10.
(The part number for a mercarb gasket set is old part number 9061 that has now superseded to 810929004.);)


Did you say that I also need a gasket set?

That is what they are calling the kit in the parts diagram, See number 29 in this link below.
Click to expand...
http://www.mercruiserparts.com/Show...RCARB)+0C856559+THRU+D447414++&+0D836076+&+UP

What is the best solution to soak the carb in?

Check with the guys at napa auto parts, They will know what works good.;)
Click to expand...
Oh yeah and if anybody has a link to a step by step rebuild process or any important tips I should know it would be greatly appreciated.
Click to expand...
You can find a step by step process in your service manual with photos.;)

Good luck with it.:)
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[FONT=Verdana, Helvetica, sans-serif]Get yourself down to a auto parts store, get a can of berrymans carb soak comes with a screen in the can, like a deep fryer.

Also get a can of compressed carb cleaner.And a carb rebuild kit. It will come with all the gaskets.

With a clean area on a table or bench i place a old cookie sheet with sides.

Break down the carb and remove all the rubber.

Remove the jets they should just screw out.

Everything goes into the berrymans, let soak for a few hours, or overnight.

Remove the parts from the berrymans, start with the lower carb housing and blow it dry with compressed air, it clean?

Piece by piece build it, make sure every passage is clean blow it dry and use compressed can carb clear blow it dry again.

Jets clean, Float, floating no gas in it ?

Push the float under water and if you see bubbles it's time to replace it.

Ok when you install the pin in the forks that hold the float are they pressing on the float tounge and not allowing the float to move freely ?

So if you did your job correctly the carb should operate freely, and when you install the adjustment screws be gentle.

Do not bend the tips. All the way in with them gently and out 2 turns to start.

Final adjustment on the water.

Have someone else drive about 2000 rpm maybe a little more and you do the final adjustmen

If you take your time and there are no distractions, you should be ok.

Good luck !

Above is copied and pasted here from another website i am the author.
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Thank you for all the help Boat_tech. I am confused on one point tho. I actualy called West Marine (where I bought the rebuild kit) and told them that the kit I bought was for a rochester carb. I gave the guy the tag number off my carb. He called the tech at Sierra and was told that my carb IS a Mercarb as you said it was, but it was made by rochester and the kit I have is the correct kit for my carb. Slightly different from what you told me. So on one hand I have your info which I consider very valuable and credable and on the other hand I have the info of the tech at Sierra that is responsible for supplying me with the correct kit. So since he insists that I have the correct kit I guess I go ahead with the rebuild with crossed fingers lol. I only paid about 25 bux for the kit so at worse I will get half way thru the rebuild only to find out that he was wrong and then I buy another kit I guess. Hopefully he knows what he is talking about. I guess if he is wrong I will have to prove it to him , geez nothing is easy with an old ass boat . Wish me luck and thanks again
 
starsh1p said:
Thank you for all the help Boat_tech. I am confused on one point tho. I actualy called West Marine (where I bought the rebuild kit) and told them that the kit I bought was for a rochester carb. I gave the guy the tag number off my carb. He called the tech at Sierra and was told that my carb IS a Mercarb as you said it was, but it was made by rochester and the kit I have is the correct kit for my carb. Slightly different from what you told me. So on one hand I have your info which I consider very valuable and credable and on the other hand I have the info of the tech at Sierra that is responsible for supplying me with the correct kit. So since he insists that I have the correct kit I guess I go ahead with the rebuild with crossed fingers lol. I only paid about 25 bux for the kit so at worse I will get half way thru the rebuild only to find out that he was wrong and then I buy another kit I guess. Hopefully he knows what he is talking about. I guess if he is wrong I will have to prove it to him , geez nothing is easy with an old ass boat . Wish me luck and thanks again
Click to expand...
Humm interesting;), lol, Well who am I to disagree with a sierra marine tech? Oh well:).

To me this is just another good reason to use "OEM" parts in my opinion.:p

Ok, So I decided to go to Sierras website to see if maybe they have a universal carb kit, And looking at all the gaskets in the kit you would think they do, judging by the photo they have of the carb kit.

So While looking up your engine serial number/ Carb number on "their" website, It appears to me that they once again quoted you the wrong part number of their carb kit.

Here is your engine / carb info, (1986 mercruiser 140 engine serial# B403574, Carb # 1389-9350).

Now Below is a copy and paste of what I found that looks like to me a much better match for your engine/Carb numbers off of the Sierra marine website.

Sterndrive 140 4 6229718 - C856558 1389-9350A2 -M2/Mercarb 18-7097 18-7202

Now Sierra said for you to use their part number 18-7746, If you look at their website below I believe you'll see that the number that they gave you will not match up to your serial numbers you have, Their numbers go to a R2/2GC style carb, Your carb is a M2/Mercarb and right next to that is Sierra part number 18-7097;):) P.S your engine specs are going to be in the eighth column down from the top in the link below.

http://www.teleflexsierra.com/Mercruiser-Stern-Drive-Carburetors-Kits-and-Related-Products/dm/cart_id.916878711--gd_get_grid.1--gd_grid_id.1616--gd_search_13395.Sterndrive%20--gd_search_13396.140--gd_search_13398.4--session_id.787522370--store_id.373--view_id.490267

But there's a good possibility that the sierra part numbers have superseded over time, and I'm not able to see it from their website, Or I could just be wrong all together.

Either way, I wish you good luck with your carb rebuild, Looks like your going to need it.;)

P.S chief, That was an excellent post on the carb rebuild you did, Good job.
 
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Thanks. Been rebuilding carbs for 40 years, small engines also.

Actually to add to my post:

When you are taking the carb apart under the accel. pump there should be a ball bearing. Remove it, there should be a new one in your kit.

Also make sure the new accel. pump fits snug in your carb.. Make sure it's the same type.

To elaborate on the 2cg carb vs the mccarb. It's actually the same carb. See there is only one adjustment screw.

If you look closely at the carb body next to the adjustment screw you should see a knockout for the other missing adjustment screw.I have been known to add another adjustment screw, from old carbs laying around.

When dismantling the carb make sure you remove the adjustment screw, treat it as you would the hope diamond, gently. When installing after cleaning the carb screw in gently DO NOT BEND THE TIP !

Ok like i said before with no distractions when putting the carb back together you should be ok.

Every gasket goes on dry. If you wish the carb to mani you may use a drop of aviation form a gasket. Just a very light coat. Do not over torque.

On the water in my post i mentioned the final adjustment.
 
lol thanks guys I will be boating someday hehehe I hope :) Thank you everybody for all the great help. I am sure that one way or another I will get this done rite. If not...... stay tuned for more dumb questions ;) Same bat time, same bat channel
 
O.K. so here we go again. After visiting the page like that Boat_Tech sent me I can clearly see that as far as that page goes, Boat_Tech is rite. Not that I want to question any of you guys be cause God knows you guys have more knowledge of these things in your little fingers than I have in my entire body. However with that said, if the two carbs are the same why do they use a much different looking float? Also if they are the same why do the two kits look so much different? So here I sit with this dilemma staring me in the face. My solution? Since I havent opened the kit I bought, I will buy the other kit also and then when I disassemble the carb I think I will then be able to match some of the parts to the kit pictures on the page. Then and it seems only then will I know for sure which kit I need. lol I will sell the other kit on E-bay since it will be unopened :) Old boat = not easy but I can take it lol. In another life I will be rich and just buy a new one ;) ya rite hahaha
 
Ha changed my mind again (I do that alot) I am going back down to West Marine (where I bought my kit) armed with print outs of the Sierra page and making them explain to me why I don't want the other kit. When they can't convince me why I want it I will return the first kit and purchase the other kit. ...Hopefully hehehe

Oh yes and now I have a new closing signature it is:


Old boat = not easy but I can take it hahaha
 
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