Hi : I have a Stihl 034 AV Super that seems to eat sparkplugs. I've been using Bosch WSR6F and after a couple of tanks of gas the saw dies. I change the plug and it fires up like nothing happened. Testing the plug with a multimeter there's no continuity from the terminal to the centre electrode.
Any thoughts on what's causing it or how to fix it?
Thanks in advance
Take care
Steve
Steve, you may have gotten a bad batch of plugs, try something different. Frank C.
Others that should work: NGK BPMR7A, Champion RCJ7Y. Gap .020".
Had the exact same problem last summer, same brand, same plug. Saw would run perfect in a cut then die like you had hit the kill switch. Give it a yank it would fire up and run perfect a cut or two then die again. I made trips to my saw shop three weekends in a row. Finally it hit me the problem started after i put in a new plug. Put a new ngk in it, problem solved. Had to have been a bad batch, i've run bosch for years with no problems, and we put two new ones in it during that problem, both from the same box of 10 or however many comes in a box. I had forgot about this until i read your post.
I'm curious what country of origin is on the box of those Bosch plugs.
Good question. I have seen this with Champion, for a while at least one plug in every box was bad, but never with Bosch.
I remember the old West German made Boschs, they were simply flawless. I still have a bunch of near new ones kicking around.
The Bosch plugs I'm currently running are made in Brazil and I've had good luck with them.
I've heard of the India manufactured ones, but I have no experience with them.
Our Bosch plugs are made in China now.
Interesting - the dead plugs I kept were made in Brazil and I'll bet they were all from the same box. I'll try the NGK ones next. I think I'll get a new coil too because I wonder if it's cooking them off. Any experience with coil problems - other than no spark at all?
Thanks
It would be hard for me to trace where the ones i had were made as its been right at a year ago. It would be interesting to know how many other saw owners had the same problem as i did out of that box of sparkplugs. My saw has run fine since the plug change.
Quote from: saw_nut on August 11, 2015, 06:19:27 PM
Our Bosch plugs are made in China now.
Where is saw_nut located?
Maybe click your user name and it will take you to your profile, and can fill in location. Then we would know where in the world you are. ;)
Looks like a Nova Scotia Canada flag saw nut is flying there.
That brings back my snowmobiling days, i had the tool box on the sled and pockets full of NGK spark plugs. The only reason i'd buy one now would be to see how far i could throw it.
I would hardly think it could be the coil, bad plugs. Back in my Husky days when i had a saw that didn't want to start, i'd swamp the plug out of a saw that was running. They both would fire right up, i told the crew it was an old Finlander trick.
Quote from: HolmenTree on August 11, 2015, 11:01:04 PM
Looks like a Nova Scotia Canada flag saw nut is flying there.
Good knowledge of geography. East coast of Canada. 23 miles inland from the Atlantic Ocean.
I bought the last box of WRS6F 'made in germany' l saw for sale. Never had issues with them but notice how days they come out of Brazil and maybe china. Having said that, l got some champion plugs on clearance at a buck or two each and they have been great too......not sure if they were out of US or China.
In my experience I had better luck with Champion then NGK.
I went through some bad NGK plugs in my bulk batch couple years ago. It happens. I gave the the NGK's away and went with Bosch only now. Someday I might not get so lucky with them.
I know back in the 80's my bro got a bad batch of Champion plugs. So just luck of whos turn it is in the pot IMO.
Another good plug l cannot complain about are from Denzo made in Japan. It amazes me how long a good plug on a well tuned OPE can last.
Just to throw my one cent in here....I only recently bought a saw under 80cc. Historically, I was a logger in the 70's and 80's and so always had/have big saws. These days I contract out fallin' to private landowners when I can get it. Recently, my J'red 80 has been going through plugs;NGK. All the plugs were bought at NAPA, so probably the same lot. They'd just die about a day or a day and a half of hard use. I've always run Bosch WS7F plugs and I can't remember why I switched to the NGK plugs.
Anyway, I found a lot of NOS, German WS7F plugs on the bay and bought them. My theory being that plugs have an indefinite shelf life. So everything got the German plugs except the 80, which got a fresh NGK from NAPA. Hardly a scientific study, but I'm hoping the NOS Bosch will do the trick. I gotta believe that due to where these plugs are made now, there's going to be lot failures. Interesting comment on the Denzo....I use them in an old Mercedes and never thought about using that brand in small engines.
Kevin
Sure it didn't slip your mind but will ask anyways.........check the gaps? Never affected me much but may as well include it in your scientific study notes........
Quote from: Warped on August 21, 2015, 10:22:58 AM
Sure it didn't slip your mind but will ask anyways.........check the gaps? Never affected me much but may as well include it in your scientific study notes........
Every plug I ever put into an engine was gaped to spec. I don't even trust them in cars out of the box pre-gapped...I find some occasionally that are wrong...only takes a sec to check. I'm a stickler for checking gaps because I used to race cars in my youth. But I understand what you're saying...some guys just throw them in an engine figuring they're 'close'. And BTW, nothing is 'scientific' about any of this, other than the likely probability that Chinese/Turkey/India made plugs will have higher failure rates than German and Japanese made plugs.
Champion in the 60's were the best plugs in the world. But over the decades like a lot of big companies, they rode on their previous reputation until it was so sullied by high failure rates, they made them good again. Trouble with that is trying to figure out which cycle the company is in at the present. When you factor in bottom line over quality, that will always be the case.
I've got Bosch plugs still from the 70's that I took out of saws and saved for no other reason except that they were in service for a longtime. I could probably put them back in and go for a few yrs yet. It just seems crazy to me that this should even an issue, but it is now.
Kevin
Quote from: saw_nut on August 12, 2015, 08:43:10 PM
Quote from: HolmenTree on August 11, 2015, 11:01:04 PM
Looks like a Nova Scotia Canada flag saw nut is flying there.
Good knowledge of geography. East coast of Canada. 23 miles inland from the Atlantic Ocean.
About 20 miles inland from me.
Initials AC perhaps?