Husky 55 rancher – nothing

[chuckp]

I replaced the coil on a husky rancher 55. I wasn't getting any spark now I'm getting great spark, but I can't even get the engine to fire at all, not even a burp.
My compression is only 120, I know that's not great, but I should get something.
Won't even attempt a fire with starting fluid what could be wrong/

 

[Gord404]

remove your muffler and check out your piston and possably your flywheel to make sure the key is intact

 

[chuckp]

the piston and cylinder have just a little but of scoring. In rather good shape. I'll check out the flywheel.

 

[chuckp]

The flywheel key is intact.

 

[Bob Hedgecutter]

Take the plug out- tip around a teaspoon full of oil on top of the piston, slosh it around a bit- cycle the engine a couple of times- put the plug back in and try to start it as per normal.

 

[chuckp]

I did what you said it almost tore my arm off. I think it might have fired once, but I could be wrong. What's that mean I don't have enough compression/

 

[Bob Hedgecutter]

I did what you said it almost tore my arm off. I think it might have fired once, but I could be wrong. What's that mean I don't have enough compression/

It means you added too much oil initially, or it did not disperse around and down the sides of the piston and you "bubba" increased the compression too much and thats why it near tore the rope from your hands.
But yes, the added oil film increases your compression for a short time- enough for a low compression engine to fire up and run like a mosquito fogger for a wee bit.

Me, I would have kept trying until it either fired up or wouldn't.
If it keeps pulling up hard on the rope on TDC- odds are compression is okay, if it was hard and then became much easier to pull- odds are the compression is down a fair bit.
Its kind of a "Heath Robinson" way of proving low compression.

 

[chuckp]

Thanks for all your help!

 

[Chevboy0167]

Did you replace the coil with China made junk or an original Husqvarna coil?

 

[Chevboy0167]

I ask cuz I ran into this with a 55 Rancher before. Showed great spark with plug out of cylinder but never with the plug in and under compression.

Yeah... it's a thing.

I bought a used OEM Husqvarna coil on eBay for $15 and it runs perfect.

 

[chuckp]

The coil is a cheap Chinese knock off.

 

[Bob Hedgecutter]

The coil is a cheap Chinese knock off.

Ah well, there ya go- might be a big part of your issue.

 

[Old2stroke]

The coil is a cheap Chinese knock off.

The main problem I have had with these AM coils is the timing is so far retarded that they won't start the engine, some as far as 8 deg ATDC. They can often be made to work by repositioning the flywheel to get at least 5 deg BTDC, however the risk in doing this is there might now be too much advance at max rpm, should not be more than 29-30 deg BTDC. You need a timing light if you are going to make these things work or pay a LOT more for an OEM unit.

 

[dandan111]

If you got spark you should have fire

 

[Bob Hedgecutter]

If you got spark you should have fire

See the post above- you can have all the spark in the world- but if occurring at incorrect timing when the gasses are not under compression- no fire will occur.

 

[chuckp]

So my problem might not be the compression after all. Is there anyway to be certain the knock off coil is screwing up the timing?

 

[stihltech]

Yes. Get rid of it and find a new or good used original equipment coil. Read above on the timing. This is why a shop does not want to work on a saw with Chinese parts. Always order 2 or 3 and you MIGHT get a good one.

 

[Old2stroke]

So my problem might not be the compression after all. Is there anyway to be certain the knock off coil is screwing up the timing?

YES, buy a timing light (they’re cheap) and learn how to use it

 

[chuckp]

There's no chance that the husky 61 coil is interchangeable with the husky 55 rancher is there

 

[Bob Hedgecutter]

55 coils are not specific to saw- lots of Husqvarna saws use the same coil- but more than a few of those like R (resistor) spark plugs only- think like size like vintage saws and see if you can find a wreck to pinch the coil from.
50, 51, 55, 254, 257, 262 are good starting list saws.