Stihl hl 100 cutting out when hot

[robmar0se]

As a newbie appreciate advice on my Stihl HL100.

As I say its cutting out, and initial thoughts it might be the ignition coil (air filter is clean).

the stampted on part nos are 4180 1305 A (2nd line MC 4180 B?), (3rd line JC 202 x) - numbers aren't clear. On the underside its says stihl ipi2000

cant find this part no but I see thtat for the HL100, 4180 400 1308 is often mentioned will this part be okay?

 

[Fish]

I doubt it, it looks like it is a unique coil to the hedge trimmers.

4249 400 1300​

​

 

[StarTech]

The HL100 used the 4180 400 1300 which has gone through several upgrades and this included the 4180 400 1305 coil. They all are superseded to the 4180 400 1308 coil which has a speed limit of 10,200 rpm.

When ran as hedge trimmer they were fitted with 4249 400 1301 from serial number 288214001 the same ignition module with a governor speed of 9,500 rpm is fitted on HL 90 K, HL 100 and HL 100 K as well.

But to answer the OP his coil is the 4180 400 1305 and yes the 4180 400 1308 is the correct replacement coil. But before replacing the coil check the RPM at full throttle as it may be hitting the speed limiter.

Reference Stihl TI 07.2014

 

[robmar0se]

The HL100 used the 4180 400 1300 which has gone through several upgrades and this included the 4180 400 1305 coil. They all are superseded to the 4180 400 1308 coil which has a speed limit of 10,200 rpm.

When ran as hedge trimmer they were fitted with 4249 400 1301 from serial number 288214001 the same ignition module with a governor speed of 9,500 rpm is fitted on HL 90 K, HL 100 and HL 100 K as well.

But to answer the OP his coil is the 4180 400 1305 and yes the 4180 400 1308 is the correct replacement coil. But before replacing the coil check the RPM at full throttle as it may be hitting the speed limiter.

Reference Stihl TI 07.2014

Thank you, best to have got a second opinion

 

[StarTech]

I just got the service info recently here myself as I just repair my first HL100. What a mess. Not only did the customer had carburetor problems the clutch was rusted up from it sitting outdoors.

Also don't forget to check the valve clearance. They are set at .004" Cold. Install new valve cover gasket after setting clearances.

 

[robmar0se]

Many thanks folks

installed new coil, but still have the same problem!!! It is cutting out when in use, starts okay.

It appears to work fine on bench both at idle, and at higher revs. I conclude that it is cutting out when twisting/rotating the trimmer in use (air filter has been cleaned).

So is it a fuel/air issue? The obvious thing to do is to replace the fuel filter which I will do, other than that would I be right to think the carb needs a clean. Ideas?

PS I haven't replaced the spark plug, but it looks fine, light grey colour as one would expect.

Thanks

 

[StarTech]

If it is cutting out because turning the trimmer on it sides then it is likely the crankshaft seals and bearing. But have you adjusted the valves?

Inlet valve = 0.10 +- 0.02 mm
Exhaust valve = 0.10 +- 0.02 mm

.10mm = .004"

 

[robmar0se]

Thanks for your reply.

My ability to start fiddling with valve clearances is beyond me. however I am trying to understand the logic of how your diagnosis results in cutting out when the item is not on an even keel/under stress; incidentally it doesn't cut out immediately, it stutters, recovers, then stutters again, may be happens a 2/3 times in short order before finally stuttering to a stop. I would have thought if it was valves/seals it would sound quite rough when running on the bench?

Having seen the price of engine parts, it might be stretch too far for a 13 year old trimmer, especially as moving later this year so wont need it beyond this year!

Appreciate your opinion, thank you for posting your input.

 

[StarTech]

My ability to start fiddling with valve clearances is beyond me. however I am trying to understand the logic of how your diagnosis results in cutting out when the item is not on an even keel/under stress; incidentally it doesn't cut out immediately, it stutters, recovers, then stutters again, may be happens a 2/3 times in short order before finally stuttering to a stop. I would have thought if it was valves/seals it would sound quite rough when running on the bench?

Not necessarily my old Husqvarna 36 would not act up until I was actually cutting up a fallen tree.

First on these 4 mix engine (hybrid 4 cycle engine) the crankcase is part of the intake system. With seals on the crankshaft they wear one sided in the most used position and harden so as the ball bearing develop play it allow the crankshaft move off center. As the engine is rotated around it allows the crankshaft to open up the seal, creating both a vacuum and pressure air leakage. The engine will lean out causing problems from a surging as the area opens and closes to an engine dying from fuel starvation. The crankshaft seals should be done by a confident 2 cycle tech as the engine must nearly fully disassembled.

This type seal wear happens even larger mower engines. I have inspected seals that I removed leaking oil that are worn one sided and harden. Just replacing the seals most times fixes the oil leaks.

Similar thing happen with the valves out adjustment as the engine can no longer properly breathe. And this adjustment requires a 1/8 wide .004" feeler gauge. The adjustment itself is quite simple though you should replace the cork rocker cover gasket at the time of the adjustment.

 

[Fish]

Likely a fuel line issue.