New Project Saw. Dolmar PS-7900!

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Does anyone have experience with the Pro-Safety 4 point spikes?

Also, should I be using the decompression switch when cold starting? It just feels like takes too many pulls. It starts fine when warm. But pulling it over without using the switch seems to be too much (like it would wear out starter components)
 
Ask Clint @cgraham1 , his show-off Dolly appears to sport those fancy spikes! :cool:

There is no reason whatsoever why the starter components would wear out noticeably faster just because You don't use the DeCo valve.
If it where the case all PS-6400/7300/7900 not featuring the DeCo valve like mine should already be on their 3 or 4 starter assembly! ;)

Unless highly squish reduced, a Dolmar PS-7900 doesn't NEED a DeCo valve! :)
They just put one in so that the not so manly built guys can enjoy running this saw without having to ask someone to start it for them! :p

If You are up to it start Your Dolmar PS-7900 without the use of the DeCo valve, it will not hurt her and she'll pop third pull cold, another 1-2 pulls without choke and she'll come to life.
I love this saw family! :heart:
 
All my Dollys start cold in 3 pulls or less with no decomp and mine all have a coil chang, carb mod and ported. All have 180+ compression.
8f62427f0fc3959cf8ef63dac7b72adb.jpg


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All my Dollys start cold in 3 pulls or less with no decomp and mine all have a coil chang, carb mod and ported. All have 180+ compression.
8f62427f0fc3959cf8ef63dac7b72adb.jpg


Sent from my SAMSUNG-SM-G900A using Tapatalk
Husky bar aside (again), another fine specimen! :cool:

And NO, I have absolutely nothing against Husqvarna or any other brand - I just think that for a photo shoot OEM or third party looks nicer. ;)
 
She's a bit nose heavy with that bar, but she pulls it like a champ! :)

My Iggesund Forest R2 bar hasn't seen much action yet - 3 cuts buried in a walnut root ball.
Dolmar PS7900 36inch Iggesund Forest R2 -1.JPG Dolmar PS7900 36inch Iggesund Forest R2 -2.JPG

I anxiously await next winters firewood log pile - which will not be purchased before next spring though. :(
 
...Man you need to make a table out of that root ball!!!...
I cut that thing up for a co-worker of mine, his intention IS to make a table top out of it! :)

He said I could have a slice, but I told him he should make his table top first and if he doesn't mess up in doing so I'd accept any one of the leftover slices.
We ended up with 3 slices total, but one was the messy root growth slice - had a nice blackish color though! :cool:
 
Thanks! It just seems to pull hard, kinda like the Pioneer without decomp. Guess I'll just yank harder lol.

Those spikes look good but seem a little less intense than the new style and I found a new stilhl roller chain catch in a box of spare parts.

Might have something else going on though. I pulled the exhaust just for the heck of it to check things and there is a light streak on the new piston. This saw doesn't have much run time on it so that's worrisome. I didn't change the seals cause they looked good but maybe I should have. And I have been running it on the rich side too. I'll take a better look tomorrow but I may be taking it back apart to inspect and possibly change seals. I hope not but I want to be safe. This saw isn't a necessity so I have the time if need be...
 
Check to see if you can feel the streak on the piston. You might post a pic if you can get a good one.
If the saws running good othe wise I fought the crank seal but its always a possibility. Did you do anything inside?? New rings etc.? Have the top apart at all??
 
I replaced the piston and rings with new oem and the cylinder cleaned up nice. It almost looked like the original was straight gassed and it was packed with sawdust. I couldnt find anything to show that an air leak was the culprit. But i dont have a vaccuum tester either. I'll have to wait until I check it tomorrow and will try to get a pic. I just didn't expect to see anything like that. I would say the new rings are barely broken in. The saw has about 5 tanks through it with the new piston. Have only ran 40:1 ethanol free as well
 
Is there any marks on the ring indicating its something hard or possibly a spec of transfer that was missed??

Sounds like it's fixable by taking it apart if need be. You can track it down by comparing the piston and cylinder and matching the spot up.
 
Well its not a lean condition. It looks like i didn't get the cylinder cleaned good enough and there was still some aluminum transfer left. I thought it was good but apparently not. My new piston isn't pristine anymore but will be fine. I'm kinda ticked because it's my fault. Glad I checked though...
 
You have seen the scoring marks on my PS-6400's piston, still runs like a champ over a Year later!
I sourced a Cabber piston ring and OEM base gaskets, but I am not in the mood to tear my saw down.

I am not proud of myself not having looked into it, I am just not blessed with time and nerves to finally do it - my job is killing me, I feel my body giving in and my brain cells dying off! :(

I wasn't always like that, I used to love tinkering all the time - not the case anymore though! :oops:
 
Some times that's a good thing to get out and tinker to get you mind off your job and work. I find it woods with me and is my therapy.

Hang in there and chin up.....even if it's hard at times.

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I tried, tinkering doesn't help me, makes me restless!

I literally need a brute force destructive ocupation to take my mind off my ****** job.
Cutting and chopping firewood was my cure for this entire last Year, by now I have enough firewood for next Year's winter and barely anything left standing to cut down.

That been said, I guess I'll have to find some other destructive occupation soon!
 
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