Husqvarna 346 cylinder bolts coarse thread?

[Backtroller]

So I'm trying to build a 346 out of a 346 and a 350, both basket cases. The 350 has fine thread m5 cylinder bolts as shown in the picture. The 346 case came with no bolts and while I believe they are m5 they are a coarse thread. The coarse threaded bolt in the photo fits well in the 346 case. However, I think these bolts are used to hold the spike in the plastic 350 case, but I'm not 100% since this saw has been a mess of mismatched parts. The 346 case is from 2000. I read a post from @sunfish saying one of his 346 had these coarse threads. All of the threads in the case seem solid and all take these coarse threads.

So, how do I get a set of 4 bolts that will work for this cylinder? I'd rather tap if possible.

 

[Tor R]

One of my 346 projects has coarse threads, I belive it's 346 xpg 00, can double check for you.
I'll see if I can find the correct bolt and size up the lenght for you.

 

[Backtroller]

Looking up 1999-2001 346xp two numbers come up 503217425 and 503215525
I'm not sure if these are different or the same but updated number.

Are these early saws all like this?

 

[Backtroller]

That would be great. Thanks

 

[Backtroller]

These are bolts I found in my Stihl pile but they are pretty short. Too short? I'm not sure what they are from but the pitch is the same.

 

[Tor R]

Looking up 1999-2001 346xp two numbers come up 503217425 and 503215525

yup, that is correct.
Your cylinder bolts is the same bolts as they use as bolts for the coil, I had 6 bolts in my cartoon.
The threads is 25mm long, ie close to 1"
Those spike bolts you was thinking about is shorter compared to coil/cylinder bolts.

View attachment 47123 These are bolts I found in my Stihl pile but they are pretty short. Too short? I'm not sure what they are from but the pitch is the same.

they are to short.

 

[Backtroller]

Thanks Tor I had 4 of those. I'm good to go.

 

[Backtroller]

Mocking up the cylinder to check squish and the bolts are a tad too long. I'm going to have to find a few small washers. These Husqvarnas are a real trip.

 

[Tor R]

Thanks Tor I had 4 of those. I'm good to go.

you find the same coil screws through 340/345/350/346/353/357/359

Mocking up the cylinder to check squish and the bolts are a tad too long. I'm going to have to find a few small washers. These Husqvarnas are a real trip.

maybe those old screws where close to bottom the case, and if you remove the gasket you get one issue.
You already has found one working solution

 

[Chainsaw Jim]

I just tore down two 350's. One pre epa and one epa model. They both have coarse threaded screws but they're not a match with thread count.

 

[dustinwilt68]

Watch @Mattyo videos on you tube, very helpful, 5 videos, full teardown and rebuold, and his had the coarse threaded bolts as well. My own 346xp and 353 have coarse as well.

 

[Mattyo]

I'm usually re tapping for finer thread these days.

 

[Backtroller]

Just for my own knowledge, Is there an actual size for these screws? I went to 2 local hardware stores and one has quite a bit of metric, but nothing was remotely close. I found lots of coarse thread in larger sizes but not in a M5. The IPL s that Husqvarna had are not that helpful.


Yes I will have to watch Mattyos 346 video again without my kids fighting and wanting my attention. My computer and TV are geared towards kiddie entertainment. Not lots of Daddy time.

 

[Mattyo]

I think the coarse thread is proprietary. The regular m5 bolts are far easier to get at the local hardware store. Be super careful the bolts aren't too long....if they bottom out before the jug seats you will have an air leak.

 

[Backtroller]

Yes they are too long. I found some washers that can make up the difference.

A few of the various Stihl screws have the same thread, but I don't know what the screw is off of so that doesn't help much.