Nissan 9.8 4-stroke Carb Varnish Help

[johncahill]

I have a 2004 Nissan 9.8 4-stroke and had to have the carb broken down, cleaned 3 years ago due to carb varnish buildup. The problem has returned again (can't run engine at low speeds or idle) and I can't get it to a shop to clean the carb professionally. Any recommendations for quick fix carb cleaner products and advise on steps to get me running again? I've heard Seafoam has been used before in similar situations with some luck.

 

[pvanv]

Re: Nissan 9.8 4-stroke Carb Varnish Help

Sorry to tell you that there is no magic "mechanic in a can" that will work on this. You can try running a super-large dose of Chevron Techron. Some swear by that, but we have had mixed results at best. In any event, it probably won't hurt. The carb needs to be removed, completely disassembled (including jets and emulsion tube nozzle), and submerged for a 4-hour bath in real carb dip, followed by a blow-out using carb spray, in order to dissolve deposits in the low-speed passages.

In the future, always run the carb dry at the end of each and every day to help prevent that varnishing.

 

[johnlcahill]

Re: Nissan 9.8 4-stroke Carb Varnish Help

Thanks, not really looking for a "mechanic in a can", just something that will allow me to get my sick motor home from the remote location it's in now. I see 2 Techron products that say they clean carbs:
1. PRO-GARD Fuel Injector Cleaner
2. Techron Concentrate Plus

Which one do you recommend and how much would you add when you say "Super Large Dose"?
I'll definately run the fuel out of the carb from now on, I wish my mechanic had told me this before.

 

[Sea Rider]

Re: Nissan 9.8 4-stroke Carb Varnish Help

Don't think Fuel Inyector Cleaners works same as on carbed engines, there are different high pressure issues involved while working between both, could try double of the recommended standard dose. Let the audience know...

Happy Boating

 

[pvanv]

Re: Nissan 9.8 4-stroke Carb Varnish Help

Thanks, not really looking for a "mechanic in a can", just something that will allow me to get my sick motor home from the remote location it's in now. I see 2 Techron products that say they clean carbs:
1. PRO-GARD Fuel Injector Cleaner
2. Techron Concentrate Plus

Which one do you recommend and how much would you add when you say "Super Large Dose"?
I'll definately run the fuel out of the carb from now on, I wish my mechanic had told me this before.

Again, we don't "recommend" the additives for cleaning... But, the product would be Techron Concentrate. And a Super-dose would be about 10 times the recommended dosage.

 

[johnlcahill]

Re: Nissan 9.8 4-stroke Carb Varnish Help

Understood. Thanks!