Maxim 750 won’t start

I have replaced the air filter, fuel filter, and spark plugs. The engine turns over and “idles” when the choke is on but dies as soon as the choke is off or I give it any gas.

 

full carb clean needed. You could have restrictions in fuel tubes, clogged jets etc.
You may have air leaks. You can test that with carb start/carb clean sprayed on the outside of the carbs to look for leaks.
IF idle rpm increases, you have air leak.

when did it last run well?

 

Thanks. It ran fine last fall. Foolishly, I did not do the routine for winter storage. Could that have caused this?

 

Is there an easy way to do a carb clean? I’ve never had to do it.

 

I have no experience doing anything "easy", I pulled mine totally apart.

A guy I know said to run seafoam into the bowls and let it soak then drain and try to run it. I never did that. Worse case is you have to do a full clean and have to replace parts you have to replace on any carb rebuild.
He said to do this:
Drain bowls
Pull fuel line off petcock, run fuel line to aux tank w/ seafoam
let sit an hour.
Drain bowls.
the problem with this is that there are soo many passages and other places that can cause issues that this won't fix those things like pulling carb and cleaning it.



Its not as hard as one thinks to pull carbs and pop off the bowls to look at what you are dealing with.
Pull tank off
Heat up the rubber with hair dryer to soften it up to make it pull out easier. Do the intake boots first. unclamp, heat up, pull off.
Take pics of how the choke/throttle cable unhooks.
Pull bottom carb bowls off (4 screws each carb) then post a pic of what you are looking at.


I've rebuilt countless small 26-85cc 2 stroke carbs and a Holly carb on my Firebird in High School and this was a little daunting at the beginning but if you watch multiple videos on Youtube, you get lots of info.

 

Phew! Okay. Thank you for the detailed steps. I have to psych myself up for this project.

 

BTW, what is “seafoam?”

 

https://seafoamworks.com/

 

Thanks. I have the carb out and waiting for the kit.

 

Hello again. Do you have any direction on the best carb repair kit for mine? Are they pretty much all the same? There are so many to choose from on Amazon.

 

You can get the carburettor kits from Len aka Chacal. Email him on info@xj4ever.com if you want.

 

Thank you. I tried to find it in the XJ parts catalog. I will email him.