Carb Rebuild - 99 Johnson 175 - Model#J175PLEES

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04-29-2011, 12:03 PM
99Ranger

Carb Rebuild - 99 Johnson 175 - Model#J175PLEES

All,

I'm about to rebuild all six carbs on my 99 Johnson 175. The guy I bought it from installed an electric fuel pump between the water seperator and the motor (which has been removed) and I believe that this has caused some of the seals or gaskets to rupture. After priming the bulb I can see fuel seep very slowly out of one of the carbs (between the float chamber and carb body) and two of the other carbs seem to be wet around the same general area. I felt it would be best to just buy 6 kits (marineengine.com, Carburetor Repair Kit #0438996) and rebuild them all.

My question is, what should I "look out for" or ensure that I do when installing the kits. It looks like a job that I can tackle myself after looking at the motor and viewing the diagram online, but I wanted to seek some advice from you guys.

Thanks,

Lee
05-01-2011, 05:03 AM
ChampioNman

Re: Carb Rebuild - 99 Johnson 175 - Model#J175PLEES (99Ranger)

I would also order 6 float bowls #433000 that way you know they are not warped and have a good seat.
05-02-2011, 03:07 PM
99Ranger

Re: Carb Rebuild - 99 Johnson 175 - Model#J175PLEES (ChampioNman)

Thanks for the advice ChampioNman, I'll order the float bowls as well. The engine runs great, except for a bit of "traileritis". I read your post regarding the throttle roller timing arm adjustment and have since moved it to the correct position but have not taken the boat out since.

Have you ever seen a case where someone installed a generic electric fuel pump between the water seperator and the motor one of these engines?
05-03-2011, 03:12 AM
SEAHORSE

Re: Carb Rebuild - 99 Johnson 175 - Model#J175PLEES (99Ranger)

double check the screws holding the carbs to the throttle bodies, the float bowls, and the side covers. Most of the carbs use Pozi-Drive screws which are NOT phillips. They have extra slots in the "cross" for a better grip. A Phillips screwdriver will wallow out the head.

Turn each screw backwards first to feel the thread "jump" into the plastic before tightening them up. You do not want to cut new threads. Do not overtighten either. Everything is plastic - actually a nylon reinforced engineering material.

You will need a factory manual to show you how and to do the adjustments and synchonization.
05-03-2011, 10:13 AM
99Ranger

Re: Carb Rebuild - 99 Johnson 175 - Model#J175PLEES (SEAHORSE)

Thanks Seahorse, they are Pozi-Drive Screws. I'm starting to think that I may have bitten off more than I can chew here.........Stupid question ahead........I didn't think that I was going to have to sync the carbs when replacing the gaskets/seals btw the float bowls, carb body, throttle body and side plates??
09-16-2018, 08:24 PM
jcfelder

I have this exact same motor, I just replaced the bowls, floats, needles and gaskets on all 6 carbs. I made sure to take eabowl off carefully and put it back in the same place it was. Motor will crank right up and idles fine, but I have noticed that it is smoking a lot and when you go to give it gas it bogs down and shuts off. Any ideas of what I need to do to correct this problem. Thanks!!
09-16-2018, 09:40 PM
316jughead

Quote:

Originally Posted by 99Ranger

Thanks for the advice ChampioNman, I'll order the float bowls as well. The engine runs great, except for a bit of "traileritis". I read your post regarding the throttle roller timing arm adjustment and have since moved it to the correct position but have not taken the boat out since.

Have you ever seen a case where someone installed a generic electric fuel pump between the water seperator and the motor one of these engines?

For the 1000th time, there is more to the timing roller adjustment than just moving the roller, please read that entire post. The important thing is that the timing starts to advance and the carbs start to open at exactly the same time. Having a gap between the timing roller and the timing arm is not always the problem and just removing the gap is not always the cure. You don't have to synk the carb butterflies when doing a carb job, but a real carb job includes making sure that the carbs are closed at idle and that they are all in synk and open at the same time. Take the top carb off first and put a shorter carb bolt in the throttle body, this will keep the throttle body from moving on the intake, there is already a bolt at the bottom to hold the body in place. Then take the other carbs off. I find that this makes it easier, just install the bottom carb first, much easier to see if the oring gasket is in place. You do need to get a real OMC service manual for your motor, they are packed with good info.
09-16-2018, 09:48 PM
316jughead

Quote:

Originally Posted by jcfelder

I have this exact same motor, I just replaced the bowls, floats, needles and gaskets on all 6 carbs. I made sure to take eabowl off carefully and put it back in the same place it was. Motor will crank right up and idles fine, but I have noticed that it is smoking a lot and when you go to give it gas it bogs down and shuts off. Any ideas of what I need to do to correct this problem. Thanks!!

Hi, We can help you fix that, you should start a new thread so we don't get confused about what motor we are talking about, and please answer all questions. Thanks :smile: