Evinrude carbs.

[Monkaroo]

Hey guys , I have bought an Evinrude 175 ( 1981 model ) with the choke primer system . After having some problems with the engine bogging and stalling when I try to take off , I have discovered that it has two different types of carbs on it . The choke primer system has a fuel line which runs from the primer sylenoid to a nipple on top of each carb . One of the carbs looks to be new and has been installed on the two middle cylinders . The new carb doesn't have the nipple for the primer line to connect to , and has 5/16 on the face of it just below the barrels . The other two carbs have 3/8 on them . I'm thinking this is the size of the jets . After comparing the routing of the fuel lines from the primer sylenoid to the engine I also found that someone had plugged the nipples on the top of the top and bottom carb and had ran the primer lines to the bypass covers on the cylinders . I corrected this and ran the lines to the top and bottom carbs like my SELOC manual shows to be correct . I haven't taken it out again yet but have cranked her on the hose pipe and she seems to be ok on starting . My question is will I have to change the middle carb to the 3/8 with the fuel nipple like the others to get full performance . Thanks , Monkaroo

 

[tashasdaddy]

Re: Evinrude carbs.

check your part numbers here, follow prompts. http://www.evinrude.com/en-US/Accessories/Literature/

 

[Monkaroo]

Re: Evinrude carbs.

Thanks for the link Tashasdaddy . I've looked and looked for good detailed diagrams , with no luck . This will be a great help on a lot of my tinkering . Have a good day , Monkaroo

 

[Dhadley]

Re: Evinrude carbs.

The numbers -- 1 3/8, 1 5/16, 1 1/4 etc indicate the throat (venturi) size in inches, not the jet size. The jets are stamped with their numbers.

 

[Monkaroo]

Re: Evinrude carbs.

Thanks Dhadley , I'll pull the high speed jets and see what's up with the jet sizes . I'm thinking I might possibly have some blockage somewhere in the recirculating hoses , or check valves . The motor runs smooth once I am up and going , and will idle smooth , but I have to hit the choke when I accelerate . It bogs and tries to die until I choke it and then it will get a bite and go . I appreciate your help . Have a good day , Monkaroo

 

[Cricket Too]

Re: Evinrude carbs.

Could just be one or more carbs running lean, might just need to rebuild.

 

[Monkaroo]

Re: Evinrude carbs.

Yeah I have been thinking I might have a problem with my top carb . It had a little bit of gas around the bottom of it and the silenser cover was a little wet after I ran it the other day . I was wondering if it might have been from choking it to get it to bite and take off . I think I will pull it and drop the bowl this weekend and see what it looks like . Thanks for the help Cricket ,have a good day .

 

[emdsapmgr]

Re: Evinrude carbs.

Can you post the model number of the engine? You have some unusual parts matched to your engine. There was at least one year production where the fuel primer hoses went to the bypass covers. I did not think the 1 3/8 carbs were used on the 175 till around 89, on the big block crossflows. I am thinking you have the small bore crossflow. Possible your 1 3/8 carbs are replacements. The larger carbs flow more air/fuel and that may be contributing to your bogging. Likely your engine came with 1 5/16 carbs. In any event, you need to match all three carbs throat sizes and jet sizes in the carbs. There are internal differences even with carbs that have the same throat sizes.

 

[Monkaroo]

Re: Evinrude carbs.

Yes sir , my model # is E175TRLCIM . I think you are right on your advice . I am thinking someone might have put the carbs on with the wrong jets for my engine . I am gonna try to find the right tool to remove the jets this weekend to see if they are right . I appreciate your help greatly and will look for another reply from you tomorrow . I hope you have time to give me some further advice . Thank you , Monkaroo

 

[Dhadley]

Re: Evinrude carbs.

The carbs are jetted according to flow thu that carb, not according to horsepower.

 

[Monkaroo]

Re: Evinrude carbs.

Thanks again Dhadley , The reason I was wanting to check the jets was after looking at the evinrude parts list it showed different part numbers for jets according to the different horsepower . I am really talking out of school on this issue . I bought this boat for a project and I am determined to get it right without going to a shop if I can . You guys that know your stuff are my mentors . I really do appreciate your help . Can I replace my 175 carbs with three carbs from a 200 horse evinrude without having to rejet them ? And if so will it give me any more muscle ? From what I have been able to sort out on this , the carbs on my engine and the carbs on the 200 engine are identical from 1977 through 1991 except for the jets . I have access to a set of 200 carbs . Thanks again !

 

[Dhadley]

Re: Evinrude carbs.

Each carb is jetted and calibrated for how much air flows thru it, not what horsepower it's on. Even carbs with the same throat size can have very different jets. There's a lot more to calibrating a carb than just jet sizes.

We're also talking stock, recreational motors. You can put 1 3/8" carbs on a 150 and 1 1/4" carbs on a 235. You don't need to rejet them. Big carbs are going to flow more fuel, small carbs are going to accelerate better.

Depending on set up and hull design you'll see very little, if any, performance difference. You still have the same bore, stroke, ignition, intake, exhaust and gear ratio. With the big carbs (1 3/8") you'll notice the fuel consumption. We have found, again we're talking stock, recreational motors, that generally speaking the 1 1/4" carbs offer the best overall performance with the most reasonable fuel consumption on 150's, 175's & 200's.

There are several versions of the 1 1/4" carb. The one we like the best is the one used on a Sea Drive. It was used on some outboards too.

If you have a set of 200 carbs, go ahead and try them. Simple enough to try.

 

[Monkaroo]

Re: Evinrude carbs.

Oh Ok , I'll try them and see what happens . I appreciate you taking time to help me out . I'm curious to see what the carbs that are on there look like inside the bowls . The motor was supposed to be good to go on the carbs , but I removed the plugs on both sides of the carbs a couple of weeks ago and sprayed carb cleaner from one side to the other . It took a good bit of spraying to get it to clear and spray all the way through the orifices . I've ran it since then and it didn't change my bogging problem much if any . I haven't had time yet to pull the carbs . I plan on doing that tomorrow ( Sunday ) . It's obvious to me now that the 1 3/8 carbs that are on the top and bottom cylinders are the replacements and the middle carb which is 1 5/16 is the original . You've been a big help ! I hope I'm not being a pest , but I might call on ya again if you don't mind . Thanks again Dhadley :redface:

 

[Monkaroo]

Re: Evinrude carbs.

It might sound crazy , but I'm having more fun trying to solve the problems with this thing than I am running the boat . lol ........... I don't think I told you the year model on my motor it's a 1981 Evinrude 175 . Model # E175TRLCIM . I bought this thing as a project boat . It's on a 1984 Procraft fish and ski . I've done some work on the floor , replaced both fenders on the trailer , recarpeted the inside , put new bearings in the wheels , painted the motor , added a 6 inch jackplate , racarpeted the guides on the trailer , put a new 4 blade stainless steel prop on it , replaced both front seat pedestals ( drivers and front passengers ) put on a new bow stop roller , put on a new fuel line and bulb , put on new wheel bearing caps , and done a lot of cleaning and buffing . She's shaping up pretty good . I'll probably get it finished and sell it so I can buy something else to work on .lol

 

[tashasdaddy]

Re: Evinrude carbs.

it's a very contagious disease. i personally have MBS ( multiple boat syndrone). buy them fix them use them and finally sell them.

 

[Monkaroo]

Re: Evinrude carbs.

No doubt it's addicting . I pulled the carbs off yesterday and cleaned all of them . They looked pretty good inside . I made sure all of the fuel and air passages were clear . It seemed to take a little bit more spraying on the top carb to get a good clear spray on several areas , but they were all in real good shape actually . I found very little chalk in the top carb in one corner of the bowl , not much bigger than a quarter . It was only a small surface coating . The needle and seats look good too . It's kinda hard to tell , but I think I might have done some good with them . I found some small tabs on the two carbs that have been replaced with the 1 3/8 venturi that has part numbers on them , but I can't find them anywhere online by the part number to see where the heck they came from . The numbers are 395465 , and below that 235 SP , and below that 5GJMX . The 235 SP makes me think they were for a 235 engine , but I can't find them by part number or by looking at the select few 235's on the web site from the link you sent me . I just don't know about them .

 

[Dhadley]

Re: Evinrude carbs.

Yes, the 1 3/8" carbs were mainly on the 2.6 XP / GT motors. They'll work on your motor but they'll sure use a lot of fuel.

 

[Monkaroo]

Re: Evinrude carbs.

Yeah , I've got some carbs coming that were taken off of a 200 . I plan on putting them on after going through them . I can't like having the 2 carbs that are 1 3/8 and the 1 carb being the 1 5/16 . I will never be happy until I have the matching set .