35hp cough/sneeze

[AlTn]

Re: 35hp cough/sneeze

what plugs are you using?..verified 7/16" air gap spark jump?.. tested for air leaks with carb cleaner around the carb to intake and intake to crankcase gaskets?...don't give up yet

 

[Cofe]

Re: 35hp cough/sneeze

Check that carb out. Download a exploded view of the carb parts and make sure every gasket and part is in place. I once had a new kit where the gasket under the float needle valve seat was too thick compared to the old one. This made the motor run poorly and in a flooded condition. Also check that the coils have a good ground on the block. The grounding strap is located on the back side of the coils on the lower bolt hole.

My vote is to not give up. Once you get this motor going with all those new parts, you should get years of good performance.

 

[kbait]

Re: 35hp cough/sneeze

I have replaced the following: Stator, coils, plugs & wires, power pack and rebuilt the carburetor. The fuel and lines are new and tight. Link & sync done.

Expensive way to 'diagnose' a problem! The 'not much happens w/low speed adj' tells me the low speed circuit is likely still gummed up. Put some premix in a spray bottle and lightly spritz some into the carb throat when it's coughing. If it helps, you need another go at the low speed circuit in the carb. You did replace the needle retainer? Good luck!

 

[Rayandrewss]

Re: 35hp cough/sneeze

Haffiman: The pics and documentation are in previous posts
AITn: Bought new plugs...dont remember the # offhand but am using the ones per manual...7/16 gap and good spark
Cofe: I have rebuilt and cleaned this car twice according to the sticky notes and secret files found here on Iboats, coils are grounded good as I cleaned the powerhead really good when I had it off
Kbait: I did replace the needle retainer....but, I will try your idea after work tomorrow just because its fast, simple and free...lol..but to tell the truth, I dont have much faith in trying anything

This is my first motor....thought I had the "smarts" to get this thing running as the maintenance work I do engages the same "smarts" Problem is, this has made me rethink my abilities and caused me to lose faith in myself.......
If I can hold on to any of the $ from my weekend sidework (pretty much used for bills now) and I dont get it I will look at having a mechanic look at it. ( though not the last one...as he had me replace the stator and I really think it was the powerpack)....Once again, thanks for the help and pep talk guys......I will keep you posted......Ray

 

[Johny25]

Re: 35hp cough/sneeze

Ray I have confidence in you and don't give up. This is just going to make it all the sweeter when you get it going. I have been following this post all along rooting you on and I am sure there are others doing the same. I have had similar battles with motors and just had one recently with my 88' 25hp. Ended up being a leaking primer assembly and the motor needed a the proper link n sync and then she ran great after that. Mine coughed and sneezed also, and that is why I was watching your post Don't give up brother you can do it

 

[Rayandrewss]

Re: 35hp cough/sneeze

Sorry guys...no new news on the motor as I have been sick since last weekend. Back to it today if I can get the honey-do list shortened before we get rain today. If not, tomorrow looks better.

 

[Rayandrewss]

Re: 35hp cough/sneeze

Okay, spraying pre-mix into the carb helps it run better.......next step ?

 

[AlTn]

Re: 35hp cough/sneeze

back to the carb...on the rebuild did you remove and clean the orfice plug <#30 on the marineengine.com diagram >?..remove and clean under the core plug #5 and replace it? Float set parallel to carb base when inverted? Suggest running a clear fuel line from the pump to the carb to assure you are getting proper fuel flow when running...no air bubbles in the line once it's running.

 

[Rayandrewss]

Re: 35hp cough/sneeze

AITn.......been there, done that except for the clear fuel line. Did a carb rebuild and cleaned it according to the secret files here on I-boats. 2nd time, soaked the carb over the weekend. replaced and cleaned all....including your suggestions above......
Worked on it for another 3 aggravating hours today.......I really do thank everyone for their help but, I am done. I will stay with I-Boats as maybe in the future I can buy something that I can actually see run.

Once again....thank you guys.........Ray

 

[jasper60103]

Re: 35hp cough/sneeze

Bummer, I feel your pain. I read through all your old threads and concur you had a rough time with this motor. Hopefully you'll get it figured out or better luck next time.

 

[AlTn]

Re: 35hp cough/sneeze

after you've slept on it a while and feel like having another go...if you used a sierra kit to rebuild the carb several have reported that the needle valve gasket was too thick which made adjusting the float level a real trial and error procedure..if you still have the old one I'd suggest reinstalling it and giving it a go...if you tossed it, try getting just the needle valve gasket from a BRP dealer...random thought, is the choke plate opening completely once the choke solenoid is deenergized?

 

[Rayandrewss]

Re: 35hp cough/sneeze

AITn....not sure what kit I used, but I do have all my old parts, and the receipts so I can check.....and yes, the choke is open completely...

 

[Haffiman]

Re: 35hp cough/sneeze

Before you start tearing down and hunt for 'ghosts', do some basic testing so you know what works and what not.
1: Run in a barrel.
2: Get a timing light and mark as mentioned earlier the flywheel for both 1 and 2 on TDC.
3: Loosen the carb cam follower so carb does not open, only timing advance regulate rpm.
4: Start the engine and verify by timing light that only one cyl fires at the time. (hooked to #1 - can not see mark on to etc)
5: Check that engine has proper temp.
6: At lowest possible rpm, try to adjust mix screw to max rpm is obtained, then back off 1/4 - 1/2 turn.
7: Test at different rpms (still only timing advance) if any sneezing?
Results of above testing???

 

[Rayandrewss]

Re: 35hp cough/sneeze



Okay, so I cant give up....lol...dont know if its just me or all the good advice and well wishes from all you guys. Took off the carb today, cleaned it again. Did the same to the fuel pump. Tried ( i'll explain "tried" next ) to do a link & sync. Not sure what worked, but the motor is running a lot better. In the attached pic - the red line pointing out the screw is what I beleive did the link & sync.....NOT moving the plate on the stator, as it does not move at all. The green line is a question.....is there supposed to be a link here?.....the parts manual does not show one that I can see. Circled in the yellow....?....if the engine coughs it shakes the motor enough to move this advancing the revs and then settles down.......I will try to post another pic tomorrow of the other side as to what I think is happening. The needle adjust still doesnt do much but it does quiet the coughing. If it runs good now, when I put it on the lake, will I need to adjust some more, and if so, will it effect the slow speed idle again ?.

EVERYONE !!!!! thank you so much for your encouragement and help. I think I am really close to getting this thing back on water and throwing a line. More important, I have been holding off my vacation ( none in 2 years ) waiting to use my boat....I'm hoping, try the boat this weekend then in 2 weeks, take a week off.

Thanks again !!!!!

 

[Johny25]

Re: 35hp cough/sneeze

Ok Ray I am glad we are back at it again. First we need to get that link n sync dialed in or else nothing you do is going to make it run correctly. Do you have a manual for your motor? I can't look back in the thread so I can't remember what year you have but if you don't have a manual we will get you step by step directions to get this sync done right. Now is that the electric choke on the bottom right of the pic? Your carb does not resemble mine so I can't tell right off the bat if you are missing something but it sure looks like you may be?

 

[Johny25]

Re: 35hp cough/sneeze

You are missing part #57 throttle lever to the choke bellcrank in this diagram
http://www.marineengine.com/parts/j...5E79A&manufacturer=Johnson&section=Carburetor

Lets get this part fixed and then do a link n sync and see where we are ok

 

[AlTn]

Re: 35hp cough/sneeze

Ray...for your sanity..get an OMC Factory manual for your motor....ebay, ken cook co., iboats may have them too...sometimes just a pic or parts breakdown is invaluable plus the link n sync procedure will be explained in great detail..step by step...

 

[Rayandrewss]

Re: 35hp cough/sneeze

Well, got the boat on the water this morning. Started right up.....ran like a bat outa heck.....got a cough every so often but not bad at all. Got to the spot I wanted to fish across the lake. A bit windy so I decided to move to the calm side. This is about an hour later....and the boat wouldnt start. Tried a few things...no luck. Used the trolling motor to get to the other side ( 45 minutes later ). Stayed and fished for a few hours trying every so often to start the motor.....no luck. Litlle while later, just not in the mood after breaking the tip on my favorite rod decided to turn on the trolling motor and head in. Of course I had to try the motor again.......started right up !!! ran good all the way back. What a mornin......I'm thinking fuel pump, so I will go ahead and order on and try it next week. I am hoping this helps cause I start vacation a week from Monday and want to spend the week on the water as much as possible. Keep ya'll posted......as always, thank you for all your help......Ray

 

[jasper60103]

Re: 35hp cough/sneeze

Ray,
that sounds encouraging. Hope you get the rest figured out. Thanks for the update.

 

[Haffiman]

Re: 35hp cough/sneeze

I'm not quite so sure. You have two options:
1: Keep on running - works/works not and fumble around.
2: Be systematic and follow the instructions given by the board members.
Option 2 might take a bit time and effort, but without knowing exactly what is happening except works - works not, it is a bit difficult to help.
As an example: Did you have spark when engine did not start?