Hard to start

I installed the stage 2 cam n msd recently. When it cold, it pops right off. Let it sit for an hour or so, it really hard to start n sometimes backfires. Any ideas????

Here's when it's cold....
https://youtu.be/AKOffMdXXXQ

This after it sat for 2 hrs.....
https://youtu.be/jYbsJS-u2ho


And sometimes it's worse than that. Sometimes it take a few times of spinning over to start. Thanks for the help.

Are you sure you got it back in time right or the valves adjust correctly.

From what I checked yes. I marked the timing chain and cam gear and rechecked the flywheel and valve cover after installed. Everything lines up just as stock.

Did you get the decompression pin reinstalled correctly.

banchee6 wrote:

I installed the stage 2 cam n msd recently. When it cold, it pops right off. Let it sit for an hour or so, it really hard to start n sometimes backfires. Any ideas????

Are you doing anything different with the choke, to account for the differing engine temperatures ? What happens when you immediately re-start after it warms up ?

Efi and all parts were installed correctly.

As a general guideline, backfire=timing retarded to far. exhaust valve still open. glowing exhaust= timing advanced, burning not complete. Or the controller allows to much fuel.

banchee6 wrote:

Efi and all parts were installed correctly.

The thing that I am sort of focusing on is that the difference might have to do with the temperature of the engine/engine compartment based on your description. That would suggest that someting is going on with the fuel. What about when you immediately restart from shutdown, after those times that it starts well from cold conditions? I.e.: Cold=good, Lukewarm=bad, Hot=??

I certainly am not well versed on the EFI setup on the newer Rhinos. I gather that this is the first time that you have had the MSD on it? You might consider taking that back off for the time being, to get the EFI system back the way it was. Kind of a divide and conquer approach.

I'm not an efi guy at all. I did look at the msd in action on the laptop but have not clue what it's doing. I know it's rich on low end cause it takes forever to warm up according to the msd. Just kinda stumped. I'm going to check the valves tomorrow just to make sure. Just don't understand how it pops off quick and then hours later it does that sorta thing.

banchee6 wrote:

I'm not an efi guy at all. I did look at the msd in action on the laptop but have not clue what it's doing. I know it's rich on low end cause it takes forever to warm up according to the msd. Just kinda stumped. I'm going to check the valves tomorrow just to make sure. Just don't understand how it pops off quick and then hours later it does that sorta thing.

Hmmm, I wonder if it uses a temp sensor somewhere to look at, in order to know when to richen for cold starts and all of that?

I've always been a bit leary of a few lines of code running the show. I do too many typos myself to have the faith, eh?

There is a temp sensor in the air box. I wonder if I have some oil on it from the over flow from the valve cover breather. Never got my siphon break yet.

Never really ran it hard but maybe twice. I don't drive it fast at all.

call me