Stihl 038 start issue

[sherlock349]

I have recently completed an 038 full rebuild new bearings, cylinder and piston all OEM parts. After assembly compression was extremely high, making it hard to pull over. After consulting here my solution was 2 x extra base cylinder gaskets. On first start it would not start so I used easy start spray in the air filter, it started straight away. Once the saw was warmed up I tuned it and then cut up a large Ash tree. The saw is very strong, very powerful, runs and idles perfectly. The following day the saw would not start, as soon as I used easy start it started and performed excellently. I have run it for several hours (6hors) and it’s always the same. It will start immediately after use but if I leave it for a day it wont start without easy start and then it starts real easy. I have checked and changed the plug and fuel (using 50-1) Compression is 160psi no leaks on vacuum or pressure test. I did clean the carburettor as part of the build now thinking I may have missed something !
Any thoughts appreciated.

 

[qurotro]

Check your choke plate in the air filter. Looks like its not choking when cold.

 

[jacktheripper]

Stop using that starting fluid. Pull the air filter and put your thumb over the carb while pulling. I bet it will start. It's probably the choke flap in the air filter.

 

[kanscruzer]

the black choke rod is bad . lobe broken or worn

 

[sherlock349]

Thanks for the replies on this, I feel a bit dumb not thinking it through and realising it has to be the choke !!!!

 

[Al Smith]

Some 038 models used a Bing model 48 carb .This is a good carb but in some examples the fuel pump check valves if sat for a long time leak down a tiny bit .On a cold start it might take 12-15 pulls get it started again .After which more times than not will light off on one tug . I had the same problem on a modified 038 Magnum that required a D-handle to pull over ,180 PSI static .After procrastiating for several years I finally rekitted the carb which cured it .
At one time the Bing kits were only availible through a Stihl dealer to the tune of nearly 30 dollars a pop .Enter after market ,usually under $10 now .