Dolmar/makita/Solo won't start after hot. Please help

[lenbates]

Thanks for the feed back. But here is the kicker as of 2008 all 6400-7900's come with a one way vent I had 2 2007 Makita 7901's that where ported also and I didn't have as much trouble with them . So I just don't know what to do besides putting a second vent in the tank that works as a two way vent. But as much as gas costs I just hate the fact that I will be dumping my hard earned $ on the ground. I love the saws for felling but if they won't start I can't use them. I actually have been running a Brand new 365xt with a 20" bar & chain. But the carbs on them suck and the clutch side bearing and crank seal and unfortunately the 372xt's bearings go out even faster plus they won't idle consistantly. I just blew up a 365xt the other day that is why I have a new one. the cylinder plating flaked offright above the exhaust port and hit the piston and rings and Ka-Boom.


Come on you Dolmar guys what is going on with my saws? 4 saws same problem. You run them hard for a tankof fuel shut it off to refuel and then they will not start again until they are cooled down.

I've found that saws that would only start cold had incorrect spark gap - usually too small a gap. It appears that craftsman and equivalent Poulans get assembled without checking the gap.

 

[lenbates]

Fill it back up while its idling? You sure its not the ignition?

Only other thing I can think of is if its pressure and the carb needle is up and its flooding. Echo makes a couple of vents that may work for you. The first is plugged into a fuel line added to the tank, you just plug the check valve vent into the line and your done. The part number is A356000031

The other vent is used on the older 8000 and would need to have a 1/4 inch hole drilled, but once you add it, it sits just about flush and has a one way check valve built into it. Part number is 13131406320.

Hey, I'm going to try the 1/4" hole vent, after replacing my vent and still having the fuel gradually starve. It settles down and runs fine again if I set it down and open the tank a bit, so I don't think adjusting the carb is the answer. Can that second vent you mention be installed in the cap? A lot cheaper to replace if it goes wrong somehow.
Thanks,
Len Bates

 

[redhawk23]

I've found that saws that would only start cold had incorrect spark gap - usually too small a gap. It appears that craftsman and equivalent Poulans get assembled without checking the gap.

I've found that saws that would only start cold had incorrect spark gap - usually too small a gap. It appears that craftsman and equivalent Poulans get assembled without checking the gap.

Do you live in a cold climate? It Could be vapor lock due to winter formulated gas in hot temperatures. It happens every spring to me. Stihl now makes little cans of summer gas because of this problem. Solution: stock up on summer gas.

https://www.stihlusa.com/products/oils-lubricants-fuels/premixed-fuel/motomixsummerblend/

 

[lenbates]

Nope. The correct plug gap is all I needed for that craftsman 205. If you have any ideas for my Makita 7900 of be most grateful. It acts like its tank vent is plugged (gradually idle faster and faster and behind to lug with throttle, but when I open the tank a bit it returns to everything normal.) I've replaced that little valve and it's foam filter, but no changes in that behavior. It's clearly not something to adjust the Carb for because it changes by the minute. Plan B: I found a link for an echo vent that just needs a hole drilled. I'll try doing that in the easily replaced fuel cap. I'm sure that vent will be good. My two echoes have given me not trouble for years.
Any other things to check?
Thx

 

[lenbates]

Fill it back up while its idling? You sure its not the ignition?

Only other thing I can think of is if its pressure and the carb needle is up and its flooding. Echo makes a couple of vents that may work for you. The first is plugged into a fuel line added to the tank, you just plug the check valve vent into the line and your done. The part number is A356000031

The other vent is used on the older 8000 and would need to have a 1/4 inch hole drilled, but once you add it, it sits just about flush and has a one way check valve built into it. Part number is 13131406320.

Fill it back up while its idling? You sure its not the ignition?

Only other thing I can think of is if its pressure and the carb needle is up and its flooding. Echo makes a couple of vents that may work for you. The first is plugged into a fuel line added to the tank, you just plug the check valve vent into the line and your done. The part number is A356000031
.
The other vent is used on the older 8000 and would need to have a 1/4 inch hole drilled, but once you add it, it sits just about flush and has a one way check valve built into it. Part number is 13131406320.

I want to give you many thanks for providing those tank vent part numbers. I just solved the gradual leaning-out problem on my 7910 by installing that flush one. Installed a new dolkita one; made no difference. Same duckbill looking design. Maybe there's some problem down at the nipple-end of that tiny hole in the factory valve design. But now I've sidestepped it and don't need to know - in just minutes thanks to you!

 

[Old2stroke]

Not meaning to be insulting here but what is your hot-start starting procedure? Are you starting with no choke, fast idle? Some of these saws start better hot if you hold the throttle wide open when pulling them over.

 

[lenbates]

All of mine now restart hot with just a pull or two at regular idle. If one starts needing the fast idle that one gets a look at at its filter and then its plug. I use the wide throttle if I've managed to flood one - but that's more common in cold starts for me. Not often though.

 

[lenbates]

Not meaning to be insulting here but what is your hot-start starting procedure? Are you starting with no choke, fast idle? Some of these saws start better hot if you hold the throttle wide open when pulling them over.

The craftsman 205 that goes around around on my tractor could be difficult with the factory plug, which was shipped without having been gapped. Its instructions say to use the fast idle for restart, but it's really not necessary if things are right. I've also switched to non-resistor plugs in that and the Makita after having two plugs develop crazy resistance. Haven't looked back. My Echos use the non-R equivalents.

 

[pioneerguy600]

I have encountered the hard restart problem when milling with the 690 Solo and it is the ignition, it does not like heat so now I let it run for 3-4 mins at idle after a long cut, this helps greatly with reducing the temps and the saw will restart every time easily. The saw does not give any problems when its running hot but shut it off quickly and it won`t restart until it cools down, milling is definitely loading the saw and temps get on the high end doing so.

 

[lenbates]

A bandsaw mill guy I go to for cutting boards also has a big chainsaw mill rig for really big logs. He won't even mill with that unless the temps are below 60. He definitely lets the heat idle off every few minutes.