Motor Question-75 Honda 4-stroke.

[cliffy]

I noticed that past couple of seasons that my Honda 75hp 4-stroke was having difficulty starting..and idled rough...and when I tried to give it throttle, it would choke out and die. However, once I got running...warmed up...it ran just fine. I have always taken pretty good care of it...change the fluids and proper winterization/storage. I am assuming the carb is either out of whack or gunked up and needs cleaning. I changed the plugs three seasons ago...and changed the fuel filter last season. These things didnt seem to help. I dont put many hours per season on the motor...so I dont think it could be the plugs. How often do people change plugs on a 4-stroke?

Any other thoughts of what the problem might be? I am by no means a mechanic, so I brought it to an authorized Honda dealer...for service....they looked a little busy so I don’t think I will get it back anytime soon...so I am just passing my time by asking these questions. Any thoughts?

[BoxMN]

FWIW, my Honda bike was having similar symptoms. I hadn't been riding it much, and basically the carbs just got gunked up. I brought it to mech who cleaned them up, and my 12 year bike is now just like new again!

I bet you need a simple carb cleaning (but by mechanic, not bottle of stuff). Good luck!

BTW - the mech said the worst thing you can do to a bike (or motor, actually) is to NOT use it enough. That is what gunks the carbs up. Turns the fuel into varnish, or laquer or whatever it woudl be called. Gives me an excuse to use the bike more

[perchking]

I have a Honda 90 and I change plugs each year, I know I know I dont have to but I do.

I know 4 of my buddies that have Hondas and we use them 3+ days per week and they are ALL COLD BLOODED...

[Mark Christianson]

Ditto on the cold blooded.

My Honda 75 had a carb job last year, and it came back running like a top.

Mine would start fine, idle fine, but kill when I put a load on the motor(throttle up to get on plain).

[cliffy]

Well, I am glad to hear that mine isnt the only cold blooded honda out there. I have been around many boat motors in my time...and this thing is by far the coldest starting motor I have ever used. I normaly have to let it run for several minutes before I feel comfortable giving it much of any load...or else it just dies.

I am thinking it probably is just a gunked up carb....I fish mostly for muskies...so the big motor is just for running from spot to spot...and last year I didnt fish much due to a cast on the ankle...so I dont think I have gone through more than a two tanks of gas in past two years. Thanks for all the feed back. Anyone else have any thoughts?

[RainyEye]

I have a Honda 90 with a similar history, I've also found that,aside from the suggested maintenance, running a can of Seafoam with every tank of gas will keep things cleaned out very well. When I need to give it a hole shot, if I wait until it hits 2,000 RPM's it will not hesitate or stall.

[Mark Christianson]

Hey

I have a question. Any of you using a stainless prop????

I am on the fence as to if I should get one.

If you have one, what size/pitch??

sorry to divert.

I think we all agree they are cold blooded pigs, but we love em like our wives. Well, more than our wives.

[cliffy]

Yeah, I put a can threw about every other tank full...and at the end of the season.

I dont have a stainless prop....sometimes I like to get very close to structure such as reefs....I have bounced a few times...I keep a spare prop in the boat just in case.....but like I said, I have a 75hp motor and I dont think I would notice much difference in speed/hole shot...based on the type of fishing I do, I just dont think its worth the extra cost. Just my 2 cents.

Cliffy.

[Xplorer]

I have a 2000 90 Hp and have not had the cold blooded starting issue. Yes, with a carb'd motor you need to let it warm up for a bit (tho thats in the instructions in the owners manual) but mine has never stalled/quit when throttling up to WOT. I use seafaom a minimum of 3 times each year. Just added a full can yesterday on the first trip out, usually add another around 4th of July and then use it in every full tank after Labor day. The motor has been run as late as Dec 13th up here in Duluth and goes out as early as possible on Superior in the spring.

If your engine is running rough I suggest running one tank of a mixture of 2 oz. Seafoam to 1 gallon of gas instead of the usual 1 oz/gallon. This mixture will do a good job cleaning, but if you have 2+ year old gas in the tank only a thorough carb cleaning may do the trick.

No stainless prop for me, always carry a spare aluminum tho. I fish too many rocky or shallow waters to make it practical. Plus a couple more mph really isnt a big deal to me, I've hit 39.1 gps at WOT max (1/2 tank 2 guys), and can run 38 most anytime.

PS: I have about 400 hours on the motor and am still running the original plugs and fuel filter (check/clean them about 1/2 way thru each season). I do quite a bit of trolling with the 90 for lakers/salmon and backtrolling bottombouncers and feel the seafoam really helps for extended low rpm use.

[pfluemis]

Quote:

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I noticed that past couple of seasons that my Honda 75hp 4-stroke was having difficulty starting..and idled rough...and when I tried to give it throttle, it would choke out and die. However, once I got running...warmed up...it ran just fine. I have always taken pretty good care of it...change the fluids and proper winterization/storage. I am assuming the carb is either out of whack or gunked up and needs cleaning. I changed the plugs three seasons ago...and changed the fuel filter last season. These things didnt seem to help. I dont put many hours per season on the motor...so I dont think it could be the plugs. How often do people change plugs on a 4-stroke?

Any other thoughts of what the problem might be? I am by no means a mechanic, so I brought it to an authorized Honda dealer...for service....they looked a little busy so I don’t think I will get it back anytime soon...so I am just passing my time by asking these questions. Any thoughts?

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On my Yamaha, I've had to replace plugs every year. It would act as if it was running out of gas, then take off, repeating, over and over, until I change the plugs. Just off idle, WOT, it didn't matter. Hesitation off idle, then smoothing out is generally a lean fuel mixture issue. It could be from either an intake leak, plugged idle circuit, bad fuel, or accelerator pump problems. Basically, the motor is starving, then dieing. Being cold blooded, is different. It generally means your not getting good atomization of the fuel being drawn into the motor. The old way of curing this was to run with the choke partially on until it warms up. Modern EFI, computer monitored motors, compensate for this issue until warmed up.

[cliffy]

Well, I got my boat back today from the marine repair shop. OUCH!!! Cost me nearly 800.00 dollars....to fix the card and gas gauge. 600.00 in labor. WOW!!!

When the clerk asked me my method of payment, the phrase, " thru my nose" came to mind . Oh well, it runs great now...better then when I bought it (it was used). I guess this shows how important it is to properly winterize you motors..etc. I always thought I did...but I suspect the previous owner may not have done so. Lesson learned.

Cliffy.