Husqvarna 371 Starting Issue

[Drooplawns]

Newbie here...been lurking around this forum for quite awhile, learnt alot in that time. Now I have a problem, lol. Husqvarna 371 modded muffler, custom tank vent, 345 limitless coil. Fun, fast cutter. Problem: after setting a couple days will not start, crank all I want, will not fire till I remove air filter and "prime" engine with a shot of mixed fuel down intake, then it fires and runs. Thinking crank seals, but want some input before tearing into it. Thanks for any input!!!

 

[redoakman]

wait why did you put a 345 unlimted coil on . i thought the 371 had an unlimted coil to start with . check the fuel to see if there's water in it, any cracked hoses , new plug . thats where i would start

 

[lone wolf]

Newbie here...been lurking around this forum for quite awhile, learnt alot in that time. Now I have a problem, lol. Husqvarna 371 modded muffler, custom tank vent, 345 limitless coil. Fun, fast cutter. Problem: after setting a couple days will not start, crank all I want, will not fire till I remove air filter and "prime" engine with a shot of mixed fuel down intake, then it fires and runs. Thinking crank seals, but want some input before tearing into it. Thanks for any input!!!

Well check the fuel line with a vac tester to see if leaks for starters. Then you can vac test the engine.

 

[Drooplawns]

Has new fuel line, but I'll check it on your recommendation. Where exactly do I obtain a vac tester, would a vacuum brake tester work? 371 coil was blue, dealer said "they were rev limited", can't vouch for it personally, but I changed it only because it broke down internally. Amazingly the 345 coil fit.

 

[lone wolf]

Has new fuel line, but I'll check it on your recommendation. Where exactly do I obtain a vac tester, would a vacuum brake tester work? 371 coil was blue, dealer said "they were rev limited", can't vouch for it personally, but I changed it only because it broke down internally. Amazingly the 345 coil fit.

A brake tester will work .

 

[angelo c]

First ? How are you tuning it. ?
Next im looking for a vacuum leak.

I take that back...maybe the different coil is timed differently ?
Causing a rough start..

 

[old-cat]

I'm thinking fuel pump diaphram in the carb

 

[pantelis]

I must agree 100 % with the old- cat , because if the pump diaphragm in the carb have problem ..................................
the explaination is why when you put a litlle fuel in the cylinder the saw can start, but when you pull the cord dont.
also a seals leak dont stop the saw from starting.
but anyway good is to make a pressure-vacuum test

 

[decableguy2000]

What is a custom tank vent. The OEM ones are readably available. Pictures please.

Jeremy

 

[Drooplawns]

Its been over a year since I got the saw and fixed it up.to running shape, so mods shouldnt be a poblem. As for the tank vent, previous owner drilled stock vent out, along with alot of tank plastic. Will dissassemble saw later this week and get back with results and pics.

 

[Drooplawns]

Finally made it back to work on my saw. Ok, custom tank vent: a piece of brake line was pressed into a larger piece of brake line, and brazed together, then ground down to form a smooth transition between the two. A piece of plastic flex tube was slid into the oversize tank vent hole, then the metal tube was pressed into the plastic tube, firmly securing it. The metal stub protruding from the plastic line was then fitted with a piece of fuel line and run up next to the air filter and a stihl tank vent inset was put in it. When I disassembled the saw, I noticed that the vent line was crushed due to the steep 90 degree turn it did, when I re-installed it, I left it coiled below the air filter deck. Would this vent crush be the trouble of my starting? It is doing much better since I had it apart for an un-related service.

 

[Ronaldo]

That may have been the problem.